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Targets Associated with Immuno Processes - Cytokine production & signalling

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Cytokine production & signalling Download as CSV
GPCRs
GtoPdb receptor name (family) Process Association Comments GO Associations Immunopharmacology Comments
5-HT2B receptor
(5-Hydroxytryptamine receptors)
The expression of 5-HT2B receptors on immune cells indicates that it plays some part in immune/inflammatory responses [653] ...
ACKR1
(Chemokine receptors)
ACKR1 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. Studies in ACKR1 null mice, and analysis of ACKR1 SNPs in asthmatic patients with poorly controlled symptoms, suggest a role for this cytokine receptor in the temporal regulation of asthma pathophysiology and symptoms [112] ...
ACKR2
(Chemokine receptors)
ACKR2 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation.
ACKR3
(Chemokine receptors)
ACKR3 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. ACKR3 binds the chemokine CXCL12 (stromal cell-derived factor 1, SDF-1 which is also a ligand for CXCR4). ACKR3 is an atypical receptor in that it does not activate G-protein-mediated signaling but induces β-arrestin recruitment [295] ...
ACKR4
(Chemokine receptors)
ACKR4 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation.
ADGRG1
(Adhesion Class GPCRs)
An association between ADGRG1 and the tetraspanin CD81, negatively regulates the immediate effector functions (inflammatory cytokine and cytolytic protein production, degranulation, target cell killing) of mature NK cells [108] ...
A2B receptor
(Adenosine receptors)
A2B receptor is discussed in this immuno-oncology review [3] ...
AT1 receptor
(Angiotensin receptors)
Accumulating evidence suggests that regulation of the mutually antagonistic angiotensin receptors AT1 and AT2 is essential for maintaining control of inflammation and that an imbalance between these two receptors has pathophysiological potential [578] ...
AT2 receptor
(Angiotensin receptors)
AT2 receptors have been have been identified on human immunocompetent cells, and selective AT2 receptor activation stimulates an anti-inflammatory effect (reduces production of pro-inflammatory cytokines TNFα, IL-6, and IL-10 after LPS challenge) in human monocytes [412] ...
C3a receptor
(Complement peptide receptors)
Complement C3a receptor 1 is the receptor for complement factor C3a, a component of the alternative complement cascade. It can have pro-inflammatory actions, but can also counteract the proinflammatory effects of C5a.
The complement system plays a critical role intestinal immune homeostasis. In particular, C3 and the C3aR have been identified as being involved in regulating the intestinal immune response during chronic colitis [604,667] ...
C5a1 receptor
(Complement peptide receptors)
C5aR is typically associated with the compement cascade and innate immunity.
MorphoSys have an anti-C5aR monoclonal antibody (MOR210; TJ210) in preclinical development as an immuno-oncology agent. The goal of anti-C5aR therapy is to reduce the effects that activation of the C5a/C5aR axis has on promoting cancer cell migration and invasiveness [261,389,446-447] ...
C5a2 receptor
(Complement peptide receptors)
C5aR is typically associated with the compement cascade and innate immunity. However, the complement C5a receptor 2 may act as a decoy receptor for C5a, as it has no reported G protein signalling capacity.
CCR1
(Chemokine receptors)
CCR1 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation.
CCR10
(Chemokine receptors)
CCR10 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation.
CCR2
(Chemokine receptors)
CCR2 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. CCR2 is discussed in relation to immuno-oncology in [3] ...
CCR3
(Chemokine receptors)
CCR3 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation.
CCR4
(Chemokine receptors)
CCR4 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation.
In disease states CCR4 is involved in recruiting T helper type 2 cell (Th2) subsets in autoimmune disorders such as asthma, allergic rhinitis, and atopic dermatitis [580] ...
CCR5
(Chemokine receptors)
CCR5 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. CCR5 is discussed in relation to immuno-oncology in [3] ...
CCR6
(Chemokine receptors)
CCR6 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. CCR6 is expressed on a variety of immune cells including memory and regulatory T-cells [316,367] ...
CCR7
(Chemokine receptors)
CCR7 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation.
CCR8
(Chemokine receptors)
CCR8 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation.
CCR9
(Chemokine receptors)
CCR9 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. Activation of CCR9 by CCL25 plays a key role in leukocyte recruitment to the gut and CCR9 antagonists are being pursued as therapeutic agents for inflammatory bowel disease [668] ...
CCRL2
(Chemokine receptors)
CCRL2 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. However, the nomenclature of CCLR2 for this receptor and its classification as a member of the chemokine receptor family is prov ...
chemerin receptor 1
(Chemerin receptors)
Studies in CMKLR1 (chemerin receptor 1) knockout mice highlight the role of this receptor in inflammation and obesity. Chemerin receptor 1 is activated by the lipid-derived, anti-inflammatory autacoid ligand resolvin E1. As its name suggests, reslovin E1 is involved in resolving physiological inflammatory responses. The metabolically stable resolvin E1 analogue, RX-10045 (navamepent) has completed Phase 2 clinical trials in several occular inflammation indications. In relation to multiple sclerosis (MS), clinical EAE is significantly reduced in CMKLR1 KO mice. Taking this in to consideration with data that confirm CMKLR1 expression by the main effector cells in MS, this protein is judged to be a novel and tractable target for therapeutic intervention in MS. CMKLR1 antagonists are being pursued as anti-inflammatory agents. The selective CMKLR1 antagonist CCX832 was developed by ChemoCentryx and GlaxoSmithKline as a potential anti-psoriatic medication, but development appears to have halted at Phase 1. is a CMKLR1 antagonist that has shown efficacious effects applicable to MS in vitro and in vivo [222] ...
CXCR1
(Chemokine receptors)
CXCR1 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. CXCR1 is discussed in relation to immuno-oncology in [3] ...
CXCR2
(Chemokine receptors)
CXCR2 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. CXCR2 is discussed in relation to immuno-oncology in [3] ...
CXCR3
(Chemokine receptors)
CXCR3 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. CXCR3 is the receptor for CXCL9, -10 and -11, three CXC chemokines that are preferentially expressed on Th1 lymphocytes.

In the cancer setting cytokines are known to establish an immunosuppressive milieu that is condusive to tumour progression. CXCR3 and its ligands have specifically been identified as being associated with this mechanism in pancreatic ductal adenocarcinoma [93] ...
CXCR4
(Chemokine receptors)
CXCR4 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. Due to its role in cancer cell homing and metastasis the CXCR4-CXCL12 axis is a potential target for cancer therapy [518,549,647,659] ...
CXCR5
(Chemokine receptors)
CXCR5 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation.
CXCR6
(Chemokine receptors)
CXCR6 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. CXCR6 is upregulated by IL-2 and IL-15 [631] ...
CX3CR1
(Chemokine receptors)
CX3CR1 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation.
D2 receptor
(Dopamine receptors)
D2 receptor-mediated anti-inflammatory effects in the kidney have a protective effect. In contrast, impaired D2 receptor function results in renal inflammation and organ damage [720] ...
EP3 receptor
(Prostanoid receptors)
Foudi et al. (2012) [194] ...
EP4 receptor
(Prostanoid receptors)
The EP4 prostanoid receptor is one of four receptor subtypes for prostaglandin PGE2. The anti- and pro-inflammatory (and non-inflammatory) activities of this receptor are reviewed in [702] ...
FFA2 receptor
(Free fatty acid receptors)
FFAR2 is a GPCR activated by short-chain fatty acids, and evidence suggests that FFAR2 (and FFAR3) mediate beneficial effects associated with a fiber-rich diet. These GPCRs are of interest as targets for the treatment of inflammatory and metabolic diseases. FFAR2 is included in GtoImmuPdb as it is highly expressed on immune cells, in particular neutrophils, and evidence points to a role in diseases with dysfunctional neutrophil responses, such as inflammatory bowel disease (IBD). A Phase 2 trial of the clinical candidate GLPG0974 in ulcerative colitis has been completed (see NCT0182932).
In vitro and in vivo studies suggest that the short-chain fatty acid/FFAR2 axis is modulated by metabolites of cholera toxin, that are produced by gut microbiota, which leads to enhanced mucosal antibody responses against enteric pathogen infection [694] ...
FFA3 receptor
(Free fatty acid receptors)
FFA3 has been included in GtoImmuPdb as its expression has been detected in immune cells [76] ...
FFA4 receptor
(Free fatty acid receptors)
FFA4 has been identified as a drug target in asthma and COPD [508] ...
FPR1
(Formylpeptide receptors)
The primary function of FPR1 is recognition of formylpeptides. Detection of bacterial N-formylpeptides via FPR1 activates immune-cell chemotaxis and cytokine release, making this GPCR an important component of the host defense mechanism.

Osei-Owusu et al. (2019) demonstrated that FPR1 on immune cells is the target of the needle cap protein (LcrV; Uniprot accession P0C7U7) of Yersinia pestis (the plague bacterium), via which the bacteria destroy host immune cells [469] ...
GPR35
(Class A Orphans)
GPR35 is expressed by dendritic cells, macrophages, and granulocytes, all of which show chemotactic response to CXCL17 [492] ...
PAF receptor
(Platelet-activating factor receptor)
PAF deficiency results in defective inflammatory response to infection in mice.
PAR1
(Proteinase-activated receptors)
PAR1 has been found to mediate the effects of neutrophil elastase (NE) on γδ T cell activation, as the PAR1 inhibitor abrogates NE (from neutrophils)-induced activation of these T cells [624] ...
PAR2
(Proteinase-activated receptors)
PAR2 receptors have been reported to elicit pain and inflammation through a neurogenic mechanism of action, causing release of substance P, activation of NK1 receptors, and sensitization of TRPV1 voltage-gated ion channels. This action can be negated using a selective NK1 receptor antagonist (L732,138) or a TRPV1 receptor antagonist (capsazepine) [205] ...
S1P1 receptor
(Lysophospholipid (S1P) receptors)
S1P1R activation by agonists downregulates allergic inflammation (i.e. it has an inhibitory effect) [269,272,548] ...
S1P3 receptor
(Lysophospholipid (S1P) receptors)
succinate receptor
(Succinate receptor)
Succinate acts an an alarmin that triggers the initiation and propagation of danger signals resulting from tissue injury or inflammatory stimuli. It acts through the succinate receptor, SUCNR1. SUCNR1-expressing macrophages release succinate that acts in an autocrine and paracrine feed-forward loop that elevates SUCNR1 expression and leads to enhanced IL-1β production [371] ...
XCR1
(Chemokine receptors)
XCR1 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. XCR1 is expressed by a subset of dendritic cells [352] ...
Ion Channels
GtoPdb receptor name (family) Process Association Comments GO Associations Immunopharmacology Comments
nicotinic acetylcholine receptor α7 subunit
(Nicotinic acetylcholine receptors (nACh))
Included in Guide to Immunopharmacology as CHRNA7 knockout aggravates rheumatoid arthritis in mice [638] ...
P2X7
(P2X receptors)
The P2X7 receptor is involved in NLRP3-type inflammasome formation, and subsequent maturation of IL-1β [370,521] ...
TRPM4
(Transient Receptor Potential channels (TRP))
TRPM4 is expressed on human T cells, mouse dendritic cells, human and mouse monocytes/macrophages, and mouse mast cells [478] ...
TRPV1
(Transient Receptor Potential channels (TRP))
Several lines of evidence suggest that TRPV1 is implicated in some inflammatory processes [27,52,383,391,546] ...
TRPV4
(Transient Receptor Potential channels (TRP))
Expressed on mouse neutrophils [478] ...
Nuclear Hormone Receptors
GtoPdb receptor name (family) Process Association Comments GO Associations Immunopharmacology Comments
Farnesoid X receptor
(1H. Liver X receptor-like receptors)
FXR is predominantly expressed in liver, intestine, kidney and adipose tissue, but has also been detected in immune cells (CD4+, CD8+, CD19+ and CD14+ cells) [556] ...
Liver X receptor-α
(1H. Liver X receptor-like receptors)
Liver X receptors (LXR) are involved in the regulation of lipid metabolism and inflammatory responses. As such they are novel drug targets for cholesterol homeostasis (hypercholesterolaemia), inflammation, and with potential therapeutic effects in neurodegenerative diseases [683] ...
Liver X receptor-β
(1H. Liver X receptor-like receptors)
Liver X receptors are involved in the regulation of lipid metabolism and inflammatory responses. LXRs are drug targets for cholesterol homeostasis (hypercholesterolaemia), inflammation, and with therapeutic potential in neurodegenerative diseases [683] ...
Peroxisome proliferator-activated receptor-γ
(1C. Peroxisome proliferator-activated receptors)
PPARγ agonists have anti-inflammatory effects. Full PPARγ agonists can cause undesireable weight gain, but partial agonists are devoid of this adverse effect and retain the anti-inflammatory effects of PPARγ modulation.
The PPARγ agonist boosts the inflammatory phenotype of microglia and enhances their phagocytic capacity [338] ...
RAR-related orphan receptor-γ
(1F. Retinoic acid-related orphans)
RORγ is a nuclear receptor transcription factor that acts as an immune cell master control switch (most likely associated with expression of the RORγt isoform). This receptor is an essential regulator of type 17 effector T cell differentiation and function. RORγt inhibitors (antagonists and inverse agonists) [148,209,449,584] ...
Retinoic acid receptor-γ
(1B. Retinoic acid receptors)
Retinoid drugs reduce the proinflammatory factors and disrupt the immunoinflammatory cascade associated with acne vulgaris. RARγ is one of the molecular targets of anti-acne retinoid family drugs. RARγ-selective retinoid derivatives are being investigated as topical agents, which are exp ...
Enzymes
GtoPdb receptor name (family) Process Association Comments GO Associations Immunopharmacology Comments
5-LOX
(Lipoxygenases)
5-LOX is included in GtoImmuPdb because of its involvement in eicosanoid turnover and because it is being actively pursued as a molecular target for the development of novel anti-inflammatory therapeutics [575] ...
ABL proto-oncogene 1, non-receptor tyrosine kinase
(Abl family)
Included in GtoImmuPdb based on its association with leukemia.
aconitate decarboxylase 1
(Itaconate biosynthesis)
Itaconate (itaconic acid) is generated from the citric acid (TCA) cycle intermediate cis-aconitic acid which is produced by mitochondria. Itaconate is synthesised by the enzyme aconitate decarboxylase 1 (referred to as immunoresponsive gene 1 or IRG1). Its synthesis links metabolism to immunity and it plays an important role in the macrophage-based immune response [132,165] ...
ADAM10
(M12: Astacin/Adamalysin)
ADAM10 has been identified as the primary physiologically relevant sheddase responsible for cleavage of , and regulation of ICOS/ICOSL-dependent immune responses [384] ...
ADAM17
(M12: Astacin/Adamalysin)
The proteolytic activity of ADAM17 (a type I transmembrane metalloproteinase; a.k.a.TNF-alpha converting enzyme or TACE) is involved in the shedding of the extracellular domains of several transmembrane proteins e.g. cytokines (TNFα), growth factors, receptors (IL-6R and TNF-R for example) and adhesion molecules. Cleavage of substrates, including TNFα, IL-6R and L-selectin, produce pro-inflammatory effects stimulating both innate and acquired immune responses. ADAM17 activity is crucial during development (ADAM17 knockout is embryonic lethal), and it has been shown that the soluble IL-6R/IL-6 complex generates agonist-like signals in a process termed IL-6 trans-signaling. The generation and maintenance of several inflammatory and autoimmune diseases is driven by IL-6 trans-signaling [105] ...
ADAM33
(M12: Astacin/Adamalysin)
ADAM33 is implicated in the pathology of asthma [636] ...
ADAM8
(M12: Astacin/Adamalysin)
ADAM8 is reported to drive acute allergen-induced airway inflammation in a mouse model, and effect negated by ADAM8-deficiency (antibody-induced or gene knockout) [485] ...
Arginase I
(Arginase)
The role of ARG1 in immuno-oncology is reviewed in [3] ...
Arginase II
(Arginase)
The role of ARG2 in immuno-oncology is reviewed in [3] ...
beta adrenergic receptor kinase 1
(Beta-adrenergic receptor kinases (βARKs))
GRK2 (βARK1) expression and activity are downregulated in lymphocytes from RA patients [379] ...
Bruton tyrosine kinase
(Tec family)
The TEC family protein tyrosine kinases have been identified as key components of T-cell-receptor activation and signalling. TEC family kinases are expressed predominantly by haematopoietic cells. T cells express ITK, TXK and TEC [50] ...
casein kinase 2, beta polypeptide subunit
(Casein kinase 2 (CK2) family)
CSNK2B is included in Guide to IMMUNOPHARMACOLOGY as it is a subunit of the casein kinase 2 complex.
Caspase 1
(C14: Caspase)
Caspase 1 is also known as interleukin-1beta (IL-1α) converting enzyme (ICE). Amongst its substrates are the precursors of the inflammatory cytokines IL-1β and IL-18, which it proteolytically cleaves into active mature peptides.
Caspase 3
(C14: Caspase)
Defective caspase 3 expression in immune effector cells may influence susceptibility to Kawasaki disease, an acute vasculitis syndrome affecting small- and medium-sized arteries of infants and children [466] ...
Caspase 4
(C14: Caspase)
Recognition of cytoplasmic lipopolysaccharide (LPS) by Inflammatory caspases including caspases-4 and -5 leads to pyroptosis and secretion of inflammatory mediators [569-570] ...
Caspase 8
(C14: Caspase)
Roles of apoptotic caspases extending beyond cell death, for example, mediating cellular immune processes such as inflammasome modulation, necroptosis and pro-inflammatory cytokine processing have been reported [393] ...
cathepsin B
(C1: Papain)
Cathepsins B, H and L have become important therapeutic targets as their proteolytic activity has been implicated in several pathological inflammatory conditions, such as arthritis and periodontitis. Therefore, pharmacological inhibitors of these enzymes are in development as novel therapeutics.
chitinase acidic
(Chitinases)
AMCase has been shown to be produced during type 2 inflammatory responses [726] ...
chymase 1
(S1: Chymotrypsin)
Chymase is a chymotrypsin-like serine protease that is expressed by mast cells. Amongst its activities, chymase is involved in the conversion of angiotensin (AT) I to ATII, its protease activity cleaves latent TGFβ1 and IL-1β in the cellular environment to generate the active cytokines, and it can further stimulate mast cell degranulation in a self-amplification loop. The potential of chymase as a drug target for inflammatory and gastrointestinal disorders is reviewed by Heuston and Hyland (2012) [250] ...
component of inhibitor of nuclear factor kappa B kinase complex
(IKK family)
Ikkα is one of the catalytic subunits of the IκB kinase (IKK) complex, an upstream component of the NF-κB signal transduction cascade; NF-κB signaling being involved in propagating the cellular response to inflammation. IKK frees NF-κB from its inhibitory interaction with IκBα (inhibitor of kappa B), allowing NF-κB translocation to the nucleus where it modulates transcriptional activity. Additional functions of Ikkα beyond NF-κB activation are reviewed in [263] ...
COX-2
(Cyclooxygenase)
The cyclooxygenase enzymes are included in GtoImmuPdb as they are involved in the production of inflammatory mediators, and are long-standing anti-inflammatory drug targets. The role of COX-2 in immuno-oncology is reviewed in [3] ...
C-terminal Src kinase
(Csk family)
CSK is an inhibitory regulator of Src family kinases, a family of protein tyrosine kinases indispensable to the initiation of signal transduction via ITAM-bearing immunoreceptors, and cytokine, growth factor, and pattern recognition receptor signalling. CSK phosphorylates an inhibitory tyrosine residue at the C terminus of Src kinases, leading to autoinhibition. CSK-induced Src kinase inhibition can also be mediated by binding to PEST family receptor tyrosine phosphatases [641] ...
dual oxidase 1
(NADPH oxidases)
DUOX1 participates in innate immune responses to epithelial injury and allergens, and in the development of allergic diseases [635] ...
ectonucleoside triphosphate diphosphohydrolase 1
(Hydrolases & Lipases)
Via the conversion of ADP/ATP to AMP (CD39; ENTPD1) and AMP to adenosine (CD73; NT5E) these ectonucleotidase enzymes are crucial to the regulation of purinergic signals delivered to immune cells [24] ...
elastase, neutrophil expressed
(S1: Chymotrypsin)
Neutrophil elastase (NE) is a serine proteinase with broad substrate specificity. It is stored in azurophil granules within neutrophils and is involved primarily in host defence. However, in addition to attacking proteins on invading microorganisms, secreted NE also hydrolyzes proteins of the host extracellular matrix, such as collagen-IV and elastin, hence its role in degenerative and inflammatory diseases. NE functions as a promoter of γδ T cell activation via a protease-activated receptor (PAR1)-dependent mechanism [624] ...
eukaryotic translation initiation factor 2 alpha kinase 2
(Other PEK family kinases)
Protein kinase-R (EIF2AK2) is activated by virally-introduced double-stranded RNA (dsRNA), and is therefore involved in protection against viral infection. Protein activator of the interferon-induced protein kinase EIF2AK2 (PACT; PRKRA) also activates protein kinase-R. Activated protein kinase-R phosphorylates the eukaryotic translation initiation factor eIF2α inhibiting viral protein synthesis [204] ...
FER tyrosine kinase
(Fer family)
FER acts downstream of the activated high affinity immunoglobulin epsilon receptor (FCεR1) and plays a role in FCεR1-mediated signaling in mast cells, regulation of mast cell degranulation, leukocyte recruitment, and leukocyte extravasation following bacterial lipopolysaccharide (LPS ...
FGR proto-oncogene, Src family tyrosine kinase
(Src family)
Fgr may be involved in neutrophil migration, potentially via binding to intergrins [42] ...
FKBP prolyl isomerase 1A
(Peptidyl-prolyl cis/trans isomerases)
FYN proto-oncogene, Src family tyrosine kinase
(Src family)
Animal models and cell line studies indicate a critical role for Fyn in proximal T-cell antigen receptor (TCR) signal transduction [475] ...
glycogen synthase kinase 3 beta
(GSK subfamily)
GSK3β plays an essential function in T cell differentiation and proliferation, and its activity is inhibited following antigen-driven T cell activation [57-58,381,460] ...
Haem oxygenase 1
(Haem oxygenase)
Heme oxygenase (HO) is a rate-limiting enzyme in the catabolism of heme, catalyzing the oxidative cleavage of heme (Fe-protoporphyrin-IX) to render equimolar amounts of biliverdin, ferrous iron (Fe2+), and carbon monoxide (CO).

Heme oxygenase 1 (HO1) is a Nrf2-regulated gene, whose expression is upregulated as a cytoprotective mechanism in response to cellular stresses including inflammation, ischemia, hypoxia, hyperoxia, hyperthermia, or radiation.

HO1 has antioxidant, antiinflammatory, antiapoptotic, antiproliferative, and immunomodulatory effects in vascular cells, playing an important role in the prevention of vascular inflammation and atherogenesis (reviewed in [26] ...
HCK proto-oncogene, Src family tyrosine kinase
(Src family)
Hck is thought to be involved in neutrophil migration, potentially via binding to intergrins [42] ...
heparanase
(3.2.1.- Glycosidases)
Heparanase has been studied as a novel drug target associated with the immune response and inflammation [110-111] ...
histone deacetylase 3
(3.5.1.- Histone deacetylases (HDACs))
A 2017 study reports that HDAC3 (more so than HDACs -6, -1/2, or -8) regulates inflammatory gene expression in rheumatoid arthritis fibroblast-like synoviocytes, and is required for type I IFN production [22] ...
IL2 inducible T cell kinase
(Tec family)
The TEC family protein tyrosine kinases have been identified as key components of T-cell-receptor activation and signalling. TEC family kinases are expressed predominantly by haematopoietic cells. T cells express ITK, TXK and TEC [50] ...
indoleamine 2,3-dioxygenase 1
(1.13.11.- Dioxygenases)
The indoleamine 2,3 dioxygenase (IDO) branch of the kynurenine (KYN) pathway of tryptophan metabolism has been intensely studied in relation to immune tolerance and allergy. IDO is generally considered to be a tolerogenic, immunosuppressive enzyme, that is induced by IFN-γ. It provides a negative feedback pathway that limits uncontrolled immune responses. Its immunosuppressive actions arise from its promotion of tryptophan depletion, and elevation of KYN metabolite levels. The aryl hydrocarbon receptor serves as a receptor for KYN and should be considered when evaluating the IDO-KYN pathway in immune homeostasis and its potential to modulate innate and adaptive immune responses [317] ...
Inducible NOS
(Nitric oxide synthases)
The role of iNOS in immuno-oncology is reviewed in [3] ...
inhibitor of nuclear factor kappa B kinase subunit beta
(IKK family)
Iκβ kinase β (IKK-2) is the pivotal enzyme component of the Iκβ kinase (IKK) complex, a complex crucial in regulating expression and activation of inflammatory mediators in airway epithelium. IKK-2 is an attractive target for development of pharmaceutical inhibitors with antiinflammatory action as treatments for asthma and chronic obstructive pulmonary disease (COPD) [46,65,582] ...
inhibitor of nuclear factor kappa B kinase subunit epsilon
(IKK family)
IKKε is the only inducible IKK family member. Expression is induced in response to LPS, viral infection and several cytokines. IKKε expression is restricted to pancreas, thymus, spleen and peripheral blood leukocytes. This is in contrast to all other IKK family kinases which are cons ...
INPP5D
(Inositol polyphosphate phosphatases)
SHIP1 activators are proposed as novel anti-inflammatory agents e.g. rosiptor (AQX-1125) which is in Phase 2 and 3 clinical trials [445,595] ...
interleukin 1 receptor associated kinase 1
(Interleukin-1 receptor-associated kinase (IRAK) family)
One of the two proximal mediators of IL-1 signaling via the IL-1 receptor, plays a part in IL-1-induced upregulation of the transcription factor NF-κB, the other being IRAK2. Interacts with other proteins including TRAF6, Myd88, CHUK, IKK2 and TLR4.
interleukin 1 receptor associated kinase 2
(Interleukin-1 receptor-associated kinase (IRAK) family)
IRAK2 is one of the proximal mediators of IL-1 signalling via the IL-1 receptor, the other being IRAK1. It plays a part in IL-1-induced upregulation of the transcription factor NF-κB. IRAK2 interacts with TRAF6 and Myd88.
interleukin 1 receptor associated kinase 3
(Interleukin-1 receptor-associated kinase (IRAK) family)
IRAK3 expression is restricted to monocytes and macrophages.
interleukin 1 receptor associated kinase 4
(Interleukin-1 receptor-associated kinase (IRAK) family)
IRAK4 is involved in Myddosome formation which regulates transcription factor activation and drives cytokine production to effect anti-pathogen responses and inflammation [172,436].
IRAK4 is essential for most innate immune responses to bacteria and viruses, and IRAK4 deficiency (caused by mutations) has been shown to result in recurrent invasive pneumococcal disease [410] ...
Janus kinase 1
(Janus kinase (JakA) family)
JAK1 is crucial for mediating the intracellular signals for a range of type I and type II cytokines, and for type I and type II interferons (IFN-α/β and IFN-γ respectively) following ligand-receptor interaction.
The JAK1 tyrosine kinase is crucial for signaling of certain type I and type II cytokines, via receptors belonging to the IL-2, IL-4 and IL-6 receptor families as well as neurotrophin-1 and leptin receptors (all type I cytokine receptors). JAK1 is also involved in signalling via type I ...
Janus kinase 2
(Janus kinase (JakA) family)
JAK2 signal transduction is a critical mediator of the immune response and is implicated in autoimmune conditions and in graft-versus-host disease (GvHD). The pro-inflammatory effects of IL-6, IL-12, and IL-23 on T cells are mediated via JAK2 [54,56,589] ...
Janus kinase 3
(Janus kinase (JakA) family)
Psoriatic skin samples show elevated JAK3 (and JAK1) expression, with signalling predominantly through STAT3 [18] ...
kynurenine 3-monooxygenase
(1.14.13.9 Kynurenine 3-monooxygenase)
GSK180-induced inhibition of KMO prevents multiple organ failure in rodent models of acute pancreatitis which is caused by excessive alcohol consumption [418] ...
LYN proto-oncogene, Src family tyrosine kinase
(Src family)
LYN is a Src family tyrosine kinase, expressed predominantly in hematopoietic cells, but also in neural, liver, and adipose tissues. LYN appears to function as a rheostat to modulate B cell signaling, and can be activating or inhibitory in action, depending on the B cell receptor and interacting protein complement present in particular cells [195,203,623] ...
mitogen-activated protein kinase 1
(ERK subfamily)
In endothelial cells of the vasculature, and in activated human mast cells, ERK serves as an anti-inflammatory signal that suppresses production of pro-inflammatory mediators [310,390] ...
mitogen-activated protein kinase 11
(p38 subfamily)
p38 MAP kinases are ubiquitous, highly conserved enzymes which regulate the production of proinflammatory mediators (such as TNFα and IL-1) in response to inflammatory cytokines or environmental stress [232-233,342,486,515,656] ...
mitogen-activated protein kinase 13
(p38 subfamily)
p38 MAP kinases are ubiquitous, highly conserved enzymes which regulate the production of proinflammatory mediators (such as TNFα and IL-1) in response to inflammatory cytokines or environmental stress [232-233,342,486,515,656] ...
mitogen-activated protein kinase 14
(p38 subfamily)
p38 MAP kinases are ubiquitous, highly conserved enzymes which regulate the production of proinflammatory mediators (such as TNFα and IL-1) in response to inflammatory cytokines or environmental stress [232-233,342,486,515,656] ...
mitogen-activated protein kinase 8
(JNK subfamily)
By regulating AP-1 transcriptional activity in response to cytokine activation, JNK1 contributes to the production of immunomodulators such as RANTES, IL-8 and GM-CSF .
mitogen-activated protein kinase 9
(JNK subfamily)
Experimental evidence suggests that JNK2 is important in T-cell differentiation [283,541,598,691] ...
mitogen-activated protein kinase kinase kinase 14
(STE-unique family)
NIK is a kinase that operates downstream of several TNF family receptors, including BAFF (TNFRSF13C), TWEAK (TNFRSF12A), CD40 (TNFRSF5), and OX40 (TNFRSF4), and which mediates non-canonical NF-κB signaling. BAFF, TWEAK, CD40, and OX40 are implicated in the pathogenesis of inflammatory diseases including systemic lupus erythematosus (SLE) [71] ...
mitogen-activated protein kinase kinase kinase 5
(STE11 family)
ASK1 is included in the GToImmuPdb as it is a molecular target for anti-fibrotic drug development. This kinase acts upstream of p38 MAPK and JNK kinases [271] ...
mitogen-activated protein kinase kinase kinase 7
(TAK1 subfamily)
TAK1 (MAP3K7) mediates signaling downstream of multiple cytokine receptors and is functionally important in mitogen, immune, and inflammatory signaling pathways [149,544] ...
mitogen-activated protein kinase kinase kinase 8
(STE-unique family)
MAP3K8 (a.k.a. TPL2) is the primary regulator of ERK-mediated gene transcription downstream of multiple proinflammatory stimuli [202,681] ...
mitogen-activated protein kinase kinase kinase kinase 3
(KHS subfamily)
GLK (KHS2; MAP4K3) is ubiquitously expressed. It is involved in cellular responses to stress and inflammation [162] ...
MMP1
(M10: Matrix metallopeptidase)
Overexpression of MMP-1 degrades extracellular matrix causing damage to the colon mucosa in patients with ulcerative colitis. The MMP-1 promotes secretion of TNFα causing futher damage. Levels of MMP-1 and TNFα correlate with disease severity [658] ...
MMP12
(M10: Matrix metallopeptidase)
MMP12 is included in GtoImmuPdb based on its reported involvement in asthma and potential as a asthma therapeutic target.
MMP2
(M10: Matrix metallopeptidase)
MMP2 is included in GtoImmuPdb based on its potential involvement in asthma.
MMP3
(M10: Matrix metallopeptidase)
MMP3 is included in GtoImmuPdb based on its reported involvement in inflammatory diseases.
MMP8
(M10: Matrix metallopeptidase)
MMP8 is included in GtoImmuPdb based on its potential protective role in asthma.
MMP9
(M10: Matrix metallopeptidase)
Mucosal up-regulation of MMP-9 correlates with the severity of inflammation in ulcerative colitis, and may be responsible for the mucosal damage in active ulcerative colitis [332] ...
mPGES1
(Prostaglandin synthases)
Inhibition of mPGES-1 is proposed as a potentially safer alternative to COX-2 inhibition for the treatment of pain and inflammation, with a reduced risk of cardiovascular side effects [471] ...
otulin
(C101: OTULIN peptidase)
Otulin is reported as a negative regulator of inflammation and autoimmunity [152] ...
p21 (RAC1) activated kinase 2
(PAKA subfamily)
Pharmacological inhibition of PAK2 has immunosuppressive effects [457] ...
peptidylprolyl isomerase A
(Peptidyl-prolyl cis/trans isomerases)
Cyclophilin A (CypA) is well known as a specific binding protein for cyclosporin A (CsA) [236] ...
phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha
(Phosphatidylinositol-4,5-bisphosphate 3-kinase family, Phosphatidylinositol kinases)
PI3Kα is primarily recognised for its oncogenic function. We have included it in GtoImmuPdb based on its numerous GO immune process associations.
phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit delta
(Phosphatidylinositol-4,5-bisphosphate 3-kinase family, Phosphatidylinositol kinases)
PI3Kδ is preferentially expressed in cells of hemopoietic lineage and is involved in neutrophil chemotaxis. It is the only PI3K isoform with expression restricted to leukocytes. Genetic and pharmacological inactivation of PI3Kδ indicates its importantance for the function of T cells, B cell, mast cells and neutrophils. PI3kδ is a promising target for drugs for preventing or treating inflammation, autoimmunity and transplant rejection [241] ...
phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit gamma
(Phosphatidylinositol-4,5-bisphosphate 3-kinase family, Phosphatidylinositol kinases)
The role of PI3Kγ in immuno-oncology is reviewed in [3] ...
phosphodiesterase 4B
(Phosphodiesterases, 3',5'-cyclic nucleotide (PDEs))
PDE4 is a drug target, whose inhibition has anti-inflammatory action. PDE4 inhibitors have already entered clinical use, being employed in the treatment of inflammatory skin conditions such as psoriatic arthritis () and atopic dermatitis (). PDE4B is the predominant phosphodiesterase subtype in monocytes and neutrophils and this is thought to be the sub-type central to inflammatory action of phosphodiesterases [652] ...
phosphodiesterase 4D
(Phosphodiesterases, 3',5'-cyclic nucleotide (PDEs))
The selective PDE4 inhibitor (OPA-15406) has been shown to inhibit PDE4D3 [461] ...
phosphoinositide-3-kinase regulatory subunit 1
(Phosphatidylinositol kinases)
p85α is included in GtoImmuPdb as it is the regulatory subunit of several PI3Ks (e.g. PI3Kδ and PI3Kγ) with roles in leukocyte biology and therefore important for immunity [385] ...
PLCγ2
(Phosphoinositide-specific phospholipase C)
Two structurally similar isoforms of PLCγ are expressed by mast cells (PLCγ1 and PLCγ2). Both are important enzymes in the integrated signalling pathways leading to mast cell activation [213,543] ...
proteasome 20S subunit beta 8
(T1: Proteasome)
PSMB8 is a component of the immunoproteasome [187] ...
proteinase 3
(S1: Chymotrypsin)
Proteinase 3 (PR3), called myeloblastin when it was first identified, is an abundant serine protease found principally in neutrophil granules (but is also found on the surface of quiescent human neutrophils from peripheral blood). It is stored in the primary granules of circulating neutrophils alongside other cathepsin C-activated neutrophil serine proteases (NSPs), such as human neutrophil elastase (HNE), CatG, and NSP4. In pathological conditions it is thought that PR3 behaves to accelerate inflammation, by enhancing cytokine bioactivity, inactivating anti-inflammatory mediators and by promoting tissue injury (potentially by degrading extra-cellular matrix components like elastin, collagen, fibronectin, and laminins). In addition, imbalances between NSPs and their endogenous inhibitors can contribute towards pathological tissue damage, such as the damage associated with inflammatory lung diseases like chronic obstructive pulmonary disease (COPD), emphysema, and cystic fibrosis. PR3 inhibitors are considered to be useful clinical candidates for anti-inflammatory drug development [321] ...
protein kinase C alpha
(Delta subfamily)
PKCα is included in GtoImmuPdb based on its GO immune process associations.
protein kinase C delta
(Delta subfamily)
PKCδ is included in GtoImmuPdb based on its GO immune process associations.
protein kinase C iota
(Iota subfamily)
PKCι is included in GtoImmuPdb based on the involvement of other PKC isozymes in immune processes.
protein kinase C theta
(Delta subfamily)
PKC-θ is a novel subfamily PKC found predominantly in hematopoietic cells [31] ...
protein kinase C zeta
(Iota subfamily)
PKCζ is included in GtoImmuPdb based on its GO process associations.
protein kinase, DNA-activated, catalytic subunit
(Other PIKK family kinases)
Protein kinase, DNA-activated, catalytic polypeptide (DNA-PKcs) principally acts to repair DNA in a process called non-homologous end joining (NHEJ). NHEJ is required for V(D)J recombination (somatic recombination) in developing lymphocytes during the early stages of T and B cell maturation. DNA-PKc ...
protein tyrosine kinase 2 beta
(Fak family)
FAK and Pyk2 are phosphorylated downstream of the T cell antigen receptor (TCR) to bring about receptor-specific (e.g. chemokine and integrin receptors) T cell development and activation [113] ...
protein tyrosine phosphatase non-receptor type 1
(Protein tyrosine phosphatases non-receptor type (PTPN))
Inhibition of PTPN1/2 promotes T cell-mediated anti-tumour immunity [45,365,731] ...
protein tyrosine phosphatase non-receptor type 22
(Protein tyrosine phosphatases non-receptor type (PTPN))
PTPN22 is a lymphoid-specific, inducible protein tyrosine phosphatase [130] ...
receptor interacting serine/threonine kinase 1
(Receptor interacting protein kinase (RIPK) family)
RIPK1 and RIPK3 are involved in necroptosis and as such are critical regulators of inflammation and cell death [442,525,573,646] ...
receptor interacting serine/threonine kinase 2
(Receptor interacting protein kinase (RIPK) family)
RIPK2 is involved in innate immune responses, mediating pro-inflammatory signaling from the bacterial peptidoglycan-sensing NOD1/NOD2 subfamily of innate immune pattern recognition receptors (PRRs) and signalling downstream from the Toll-like receptor (TLR) family of PRRs. Further evidence suggesting an inflammatory role is the targeting of RIPK2 (along with RIPK1/3) by the IAP family E3 ubiquitin ligases (enzymes playing a critical role in innate immunity) [455] ...
receptor interacting serine/threonine kinase 3
(Receptor interacting protein kinase (RIPK) family)
RIPK1 and RIPK3 are involved in necroptosis and as such are critical regulators of inflammation and cell death [442,525,573,646] ...
Rho associated coiled-coil containing protein kinase 2
(Rho kinase)
ROCK2 plays a role in controlling T-cell plasticity and macrophage polarization, skewing polarization towards M1-type macrophages [713] ...
sirtuin 1
(3.5.1.- Histone deacetylases (HDACs))
Sirtuin 1 has been suggested as a molecular target for host-directed therapy against Mycobacterium tuberculosis infection by research that shows that activation of sirtuin 1 decreases lung pathology, reduces inflammation, and enhances drug efficacy against Mycobacterium tuberculosis [121] ...
sphingosine kinase 1
(Sphingosine kinase)
The sphingosine kinases (SPHK1 and SPHK2; SK1, SK2) are key enzymes within the sphingolipid metabolism pathway that promote tumour growth and pathologic inflammation. SK1-selective inhibitors include PF-543 [553-554] ...
sphingosine kinase 2
(Sphingosine kinase)
The sphingosine kinases (SPHK1 and SPHK2; SK1, SK2) are key enzymes within the sphingolipid metabolism pathway that promote tumour growth and pathologic inflammation. SK2 is involved in regulating interleukin (IL)-12/interferon gamma (IFN-γ) and histone deacetylase-1/2 (HDAC-1/2) signalling, and is considered to be an anti-inflammatory enzyme with potential druggability for the treatment of autoimmune and inflammatory diseases [513] ...
sPLA2-1B
(Phospholipase A2)
sPLA2 enzymes catalyze the first step of the arachidonic acid pathway, so are inextricably involved in the production of arachadonic acid for inflammatory mediator synthesis. Excess sPLA2 activity is suggested to contribute to several inflammatory diseases. The sPLA2-1B isozyme has been reported to induce leukotriene B4 (LTB4) production in human neutrophils, using a mechanism independent of arachadonic acid generation [340] ...
spleen associated tyrosine kinase
(Syk family)
SYK plays a key role in coupling activated immunoreceptors to downstream cellular responses such as proliferation, differentiation, and phagocytosis. Mast cell, macrophage and B-cell activation (and release of inflammatory modulators) is disrupted by inhibition of SYK-mediated immunoreceptor signalling. Selective SYK inhibitors are being sought for a number of inflammatory conditions including rheumatoid arthritis, B-cell lymphoma and asthma/rhinitis [211,523] ...
SRC proto-oncogene, non-receptor tyrosine kinase
(Src family)
Src family tyrosine kinases act as general modulators of immune cell signaling, playing diverse signaling functions, both inhibitory and stimulatory, in immunoreceptor and integrin signaling pathways [382] ...
TANK binding kinase 1
(IKK family)
TBK1 belongs to the IKK-kinase family of enzymes. It is a ubiquitously expressed serine/threonine protein kinase, and constitutes a key regulatory node for several signaling pathways involved in the innate immune response that lead to induction of type I interferons. Several classes of innate sensors including the TLRs and retinoic acid-inducible gene 1 (RIG-I)-like helicases engage TBK1-IRF3 signaling pathways to regulate transcription of type I IFNs. In neuroinflammation TBK1 is involved in TLR-dependent [300] ...
tec protein tyrosine kinase
(Tec family)
The TEC family protein tyrosine kinases have been identified as key components of T-cell-receptor activation and signalling. TEC family kinases are expressed predominantly by haematopoietic cells. T cells express ITK, TXK and TEC [50] ...
tripartite motif containing 21
(2.3.2.27 RING-type E3 ubiquitin transferase)
Tripartite motif-containing (TRIM) superfamily proteins are critical in a variety of biological processes in innate immunity and are important for eradication of invading pathogens [470,516,642] ...
tripartite motif containing 38
(2.3.2.27 RING-type E3 ubiquitin transferase)
TRIM38 catalyses the ubiquitination of Lys48 of the Toll-like receptor (TLR) adaptor protein TICAM1 (commonly referred to as TRIF) which mediates its proteosomal degradation. This action has been shown to inhibit TLR3-driven type I interferon signaling of the innate immune response [685] ...
TXK tyrosine kinase
(Tec family)
The TEC family protein tyrosine kinases have been identified as key components of T-cell-receptor activation and signalling. TEC family kinases are expressed predominantly by haematopoietic cells. T cells express ITK, TXK and TEC [50] ...
tyrosine kinase 2
(Janus kinase (JakA) family)
TYK2 was the first member of the Janus kinase family to be identified. It associates with the cytoplasmic domain of type I and type II cytokine receptors, where it phosphorylates receptor subunits and facilitates signalling downstream of the receptors for the p40-containing cytokines IL-12 and IL-23 via activation of STAT-dependent transcription factors. It also mediates Type I IFN-driven responses [593] ...
Catalytic Receptors
GtoPdb receptor name (family) Process Association Comments GO Associations Immunopharmacology Comments
4-1BB
(Tumour necrosis factor (TNF) receptor family)
4-1BB is a costimulatory receptor that is highly expressed on both T cells and NK cells in the tumour environment. Since activation of 4-1BB produces an immunostimulatory effect that supports the immune cells involved in tumour control it is a target for immuno-oncology drug development [392] ...
AXL receptor tyrosine kinase
(Type XI RTKs: TAM (TYRO3-, AXL- and MER-TK) receptor family)
All three TAM family receptor tyrosine kinases are involved in regulating inflammatory responses through a negative feedback loop. Specifically, AXL-Gas6 signalling is reported to induce autophagy in murine macrophages via inhibition of the NLRP3 inflammasome, an effect which reduces hepatic inflammation in a mouse model [231] ...
BAFF receptor
(Tumour necrosis factor (TNF) receptor family)
This is a type III membrane bound receptor for B cell activating factor (BAFF). BAFF enhances B cell survival and hence regulates the peripheral B cell population. It is suggested that overproduction of BAFF may enhance the survival of autoreactive B cells, an effect which may contribute in the path ...
B cell maturation antigen
(Tumour necrosis factor (TNF) receptor family)
B-cell maturation antigen (BCMA) is a cell surface receptor for B-cell activating factor (BAFF). It interacts with various TRAF family adaptor proteins to modulate cell survival and proliferation, via NF-κB and MAPK8/JNK signal transduction pathways. BCMA is highly plasma cell-selective for malignant plasma cells from multiple myeloma (MM) patients, and is being investigated as a target for therapies to tackle relapsed/refractory MM [247,348] ...
CD27
(Tumour necrosis factor (TNF) receptor family)
CD27 (TNFRSF7) is a co-stimulatory immune checkpoint molecule that is expressed on various immune cells, including T cells and NK (natural killer) cells. The endogenous ligand for CD27 is CD70. CD27 interacts with various TRAF adaptor proteins and apoptosis regulatory protein SIVA (SIVA1). It has been recognized as playing an important role in priming, enhancing and sustaining a productive anti-cancer (CD8 T cell) adaptive immune response. CD27 is an immuno-oncology target [79,633] ...
CD30
(Tumour necrosis factor (TNF) receptor family)
Expressed by activated T and B cells. Interacts with TRAF2 and TRAF5 to elicit downstream signalling events (NF-κB activation). CD30 may protect against autoimmunity by limiting the proliferative potential of autoreactive CD8 effector T cells. CD30 is the target of the approved anti-lymphoma monoclonal antibody drug brentuximab vedotin ...
CD40
(Immune checkpoint catalytic receptors, Tumour necrosis factor (TNF) receptor family)
CD40 is a stimulatory receptor and a member of the tumor necrosis factor receptor superfamily (TNFRSF). It is expressed on a variety of immune cells, including macrophages, B cells, and dendritic cells (DCs). CD40 plays a key role in the activation of the immune system. Endogenous ligand is CD154 (C ...
CIITA
(NOD-like receptor family)
CIITA is a transcriptional coactivator for the transcription factor RFX5 [555] ...
colony stimulating factor 1 receptor
(Type III RTKs: PDGFR, CSFR, Kit, FLT3 receptor family)
Activation of the CSF1R induces myeloid proliferation, and in the tumour microenvironment this promotes M1 to M2 polarization and accumulation of tumour-associated macrophages (TAMs). The CSF1R is therefore being investigated as an immuno-oncology drug target [3] ...
Cytokine receptor common β subunit
(IL-3 receptor family)
This a signal transducing protein subunit shared by the functional receptor heterodimers for the cytokines IL-3, IL-5 and GM-CSF, with each receptor having a unique ligand binding alpha subunit.
Cytokine receptor-like factor 2
(IL-2 receptor family)
Cytokine receptor-like factor 2 is the signal transducing subunit of the functional heterodimeric receptor for thymic stromal lymphopoietin (TSLP). Ligand binding is attributed to the interleukin-7 receptor subunit α.
death receptor 3
(Tumour necrosis factor (TNF) receptor family)
In the absence of any other exogenous signals, activation of DR3 causes proliferation of FoxP3+ regulatory T cells [557] ...
death receptor 6
(Tumour necrosis factor (TNF) receptor family)
Expressed predominantly in the thymus, spleen and white blood cells. May play a role in T helper cell activation, inflammation and immune regulation. Signals via the TRADD adaptor protein to the NF-κB and MAPK8/JNK pathways.
decoy receptor 3
(Tumour necrosis factor (TNF) receptor family)
The protein product of the TNFRSF6B gene, known as decoy receptor 3 (DcR3), is a soluble endogenous receptor for three TNF family peptide ligands, LIGHT, TL1A and Fas ligand. DcR3 competes for ligand binding with death receptors. DcR3 suppresses LIGHT and FAS ligand induced apoptosis and T cell activation, and increases monocyte adhesion to endothelial cells via NF-κB activation [689] ...
DExD/H-box helicase 58
(RIG-I-like receptor family)
RIG-I is an intracellular sensor that responds to viral nucleic acids and activates downstream signaling, resulting in the induction of the type I interferon response [403] ...
DExH-box helicase 58
(RIG-I-like receptor family)
LGP2 binds RNA but does not participate in the signaling pathway that RIG-1 and MDA5 are part of, and is assumed to provide a negative feedback for IFNβ induction by sequestering pathogen-derived RNA.
Eythropoietin receptor
(Prolactin receptor family)
A non-hematopoietic EPOR-containing receptor, called the innate repair receptor (IRR) or tissue-protective receptor, down-modulates the damaging effects of the immune response to tissue injury [72] ...
Fas
(Tumour necrosis factor (TNF) receptor family)
Fas receptor (CD95) is a cell surface protein that belongs to the tumor necrosis factor receptor family, that along with its ligand CD95L (or FasL), generates a death receptor/death ligand system that mediates apoptosis induction to maintain immune homeostasis. This system is also important in the immune elimination of virus-infected cells, cancer cells and autoreactive T cells. Mouse strains with mutations in Fas or FasL develop lymphoproliferative conditions, indicating the importance of these proteins to immune cell homeostasis [606] ...
Fc fragment of IgE receptor Ia
(Fc epsilon receptors)
The product of the FCεR1A gene is a single-pass type I membrane protein that is a high-affinity receptor for immunoglobulin E (IgE). It is the ligand binding subunit of the tetrameric FCεRI, exhibiting a Kd of ~0.1nM.
Fc fragment of IgE receptor Ig
(Fc epsilon receptors)
The FCER1G protein is a gamma subunit that is utilised as part of the high affinity IgE receptor (a key complex involved in mediating allergic reactions) and other Fc receptors.
Fc fragment of IgE receptor II
(Fc epsilon receptors)
FcεRII (CD23) is the low-affinity receptor for immunoglobulin E (IgE) with a Kd > 100nM. This protein is a C-type lectin found on mature B cells, activated macrophages, eosinophils, follicular dendritic cells, and platelets. It has no structural similarities with other Fc receptors. FcεRII has functions as both a membrane-bound and as a soluble receptor [308,701] ...
fibroblast growth factor receptor 1
(Type V RTKs: FGF (fibroblast growth factor) receptor family)
A FGFR1 isoform (FGFR1(IIIc)) in complex with the Klotho protein (KL; Q9UEF7) forms a high affinity receptor for .
In the choroid plexus (the interface between the brain and immune system) Klotho enhances FGF23 signalling and activation of the NLRP3 inflammasome in resident macrophages, in a system that regulates the level of immune system activation at the blood-brain barrier. Experimental evidence from mice suggests that age-related decline of Klotho in the choroid plexus may be part of the mechanism responisble for "inflammaging", the progressive systemic increase in brain inflammation that is believed to contribute to neurodegeneration in old age [725] ...
fms related receptor tyrosine kinase 3
(Type III RTKs: PDGFR, CSFR, Kit, FLT3 receptor family)
FLT3 is the receptor for the cytokine Flt3 ligand (FLT3LG). Flt3 ligand is a growth factor akin to stem cell factor and colony stimulating factor 1, and is essential for hematopoietic progenitor cell development and expansion of both myeloid and lymphoid lineages. It is one of the growth factor receptors targeted by the chemotherapeutic tyrosine kinase inhibitor sorafenib.
Results from mouse experiments suggest that Flt3 ligand is effective in treating sepsis, by potentiating innate immune functions of dendritic cells and neutrophils and improving T cell function [483] ...
glucocorticoid-induced TNF receptor
(Tumour necrosis factor (TNF) receptor family)
GITR appears to act as a co-stimulatory immune checkpoint molecule. T cell activation induces GITR expression. GITR inhibits the suppressive activity of Treg cells and promotes survival of Teff cells.
GM-CSF receptor, α subunit
(IL-3 receptor family)
This is the ligand binding subunit of the functional GM-CSF receptor complex.
Granulocyte colony-stimulating factor receptor
(Prolactin receptor family)
This nuclear receptor mediates the effects of the cytokine, colony stimulating factor 3 (CSF3). CSF3 regulates the production, differentiation, and function of granulocytes.
herpes virus entry mediator
(Immune checkpoint catalytic receptors, Tumour necrosis factor (TNF) receptor family)
HSV viral envelope glycoprotein D (gD) binds to this protein and thereby gains entry to the cell. HVEM binds to several TRAFadaptor proteins to mediate intracellular signalling and activation of the immune response.
integrin, alpha 4 subunit (antigen CD49D, alpha 4 subunit of VLA-4 receptor)
(Integrins)
Integrin subunit alpha 4 is the alpha subunit of the α4β1 lymphocyte homing receptor. The cytoplasmic domain of α4 binds tightly to paxillin, a signaling adaptor protein, and this interaction promotes increased cell migration and inhibits cell spreading [234] ...
integrin, beta 2 subunit (complement component 3 receptor 3 and 4 subunit)
(Integrins)
ITGB2 is the beta component of the β2 integrins. It forms αβ heterodimers with the CD11 alpha subunits ITGAL (αL aka CD11a forming integrin LFA-1), ITGAM (αM aka CD11b, forming integrin Mac-1) and ITGAX (αX aka CD11c, forming integrin p150/95). Beta2-integrins are essential for leukocyte extravasation to sites of infection (i.e. leukocyte trafficking), and other immunological processes including neutrophil phagocytosis and ROS production, and T cell activation. Their absence causes a leukocyte adhesion deficiency, which manifests clinically as recurrent severe infections, defective wound healing and neutrophilia [314] ...
interferon α/β receptor 1
(Interferon receptor family)
IFNAR1 is a subunit of the functional receptor for type I interferons (NOT interferon γ). Type I interferons (IFN) exhibit an established anti-viral action. However, type I IFN signalling also appears to play a role in impaired resistance to a range of other pathogens (e.g. bacterial infection) [98,443] ...
Interferon α/β receptor 2
(Interferon receptor family)
A subunit of the functional receptor for various interferons (NOT interferon γ).
Interferon γ receptor 1
(Interferon receptor family)
A subunit of the functional receptor for interferon γ.
Interferon γ receptor 2
(Interferon receptor family)
A subunit of the functional receptor for interferon γ.
interferon induced with helicase C domain 1
(RIG-I-like receptor family)
MDA5 is an intracellualar RNA sensor. It recognizes longer double-stranded RNA sequences than RIG-1. In autoimmunity, MDA5 has been specifically linked with type I diabetes and anti-MDA5 autoantibodies can be detected in patients with certain connective tissue autoimmune conditions [6,258,415] ...
Interferon-λ receptor subunit 1
(IL-10 receptor family)
Interferon-λ receptor subunit 1 is the ligand binding component of the functional heterodimeric receptor for interferons λ1, λ2 and λ3
Interleukin 10 receptor, α subunit
(IL-10 receptor family)
Interleukin 10 receptor, α subunit is a component of the functional IL-10 receptor heterodimer.
Interleukin 10 receptor, β subunit
(IL-10 receptor family)
Interleukin 10 receptor, β subunit is a component of the functional receptor heterodimers for interleukins 10 and 22 and for interferons λ1, λ2 and λ3.
Interleukin-11 receptor, α subunit
(IL-6 receptor family)
This is the ligand-binding component of the functional receptor for interleukin 11.
Interleukin-12 receptor, β1 subunit
(IL-12 receptor family)
This protein is a subunit of both the IL-12 and IL-23 cytokine receptors.
Interleukin-12 receptor, β2 subunit
(IL-12 receptor family)
This protein is a subunit of the functional receptor heterodimer for the IL-12 cytokine.
Interleukin 13 receptor, α2
(IL-2 receptor family)
Interleukin 13 receptor, α2 acts as a high affinity decoy receptor for interleukin 13 that sequesters the ligand away from IL13Rα1 and is involved in down-regulating IL-13 responses in vivo. IL13ra2 null mice exhibit enhanced IL-13 responses [677] ...
Interleukin-13 receptor subunit α1
(IL-2 receptor family)
Interleukin-13 receptor subunit α1 is a component of the functional receptors that mediate the pro-inflammatory actions of the cytokines IL-4 and IL-13.
Interleukin-15 receptor subunit α
(IL-2 receptor family)
This is the ligand binding subunit of the functional IL-15 receptor complex.
Interleukin 17 receptor A
(IL-17 receptor family)
This protein is a common subunit shared by the heterodimeric receptors for interleukins 17 (A, B , C and F) and 25.
Interleukin 17 receptor B
(IL-17 receptor family)
IL17RB is a subunit of the heterodimeric interleukin-25 receptor.
interleukin 17 receptor C
(IL-17 receptor family)
This is a subunit of the heterodimeric interleukin-17 receptor.
Interleukin-17 receptor D
(IL-17 receptor family)
IL17RD acts as an inhibitor of proinflammatory cytokine signaling (by limiting NF-κB translocation to the nucleus) [197] ...
Interleukin 17 receptor E
(IL-17 receptor family)
This is a component of the heterodimeric interleukin-17C receptor.
Interleukin-18 receptor 1
(Immunoglobulin-like family of IL-1 receptors)
Interleukin-18 1 protein (IL18R1) is the ligand binding subunit of the functional IL-18 receptor heterodimer.
Interleukin-1 receptor-like 1
(Immunoglobulin-like family of IL-1 receptors)
IL1RL1 (ST2) is the ligand binding subunit of the functional receptor for IL-33. It is mainly expressed on mast cells, eosinophils and other immune cells [201] ...
Interleukin-1 receptor-like 2
(Immunoglobulin-like family of IL-1 receptors)
Interleukin-1 receptor-like 2 is one of the subunits of the functional receptor for IL-36.

An antibody that mimics IL-36RA's antagonist activity at the IL-36 receptor (MAB92) has been described [200] ...
Interleukin 1 receptor, type I
(Immunoglobulin-like family of IL-1 receptors)
This is one of the subunits of the functional IL-1 receptor type I heterodimer.
Interleukin 1 receptor, type II
(Immunoglobulin-like family of IL-1 receptors)
IL-1R2 acts as a decoy receptor for IL-1β, thus reducing IL-1β binding/activation of IL-1R1. IL-1R2 thereby acts to down-regulate IL-1 responses [214,440] ...
Interleukin 20 receptor, α subunit
(IL-10 receptor family)
Interleukin 20 receptor, α subunit is a component of the functional receptor heterodimer for interleukin 20.
Interleukin 20 receptor, β subunit
(IL-10 receptor family)
Interleukin 20 receptor, β subunit is a component of the functional receptor heterodimers for interleukins 19, 20 and 24.
Interleukin 21 receptor
(IL-2 receptor family)
This is the ligand binding subunit of the functional heterodimeric receptor for interleukin 21.
Interleukin 22 receptor, α1 subunit
(IL-10 receptor family)
IL22RA1 is a subunit in the heterodimeric receptors for interleukins 20 and 24 (which bind to the interleukin-22α1/20β heteromer) and IL-22 (which binds to the interleukin-22α1/10β heteromer).
Interleukin-22 receptor α2
(IL-10 receptor family)
IL22RA2 (a.k.a. IL-22 binding protein) appears to act as a high affinity, soluble monomeric decoy receptor for IL-22 capable of neutralizeing the potent antimicrobial activity of IL-22 [153,185] ...
Interleukin 23 receptor
(IL-12 receptor family)
This is one of the subunits of the functional IL-23 receptor heterodimer.
Interleukin 27 receptor, alpha
(IL-6 receptor family)
This is the ligand binding subunit of the IL-27 receptor heterodimer, a complex with IL6ST (signal transducing subunit).
Interleukin-2 receptor subunit α
(IL-2 receptor family)
IL2RA is a ligand binding component of the IL-2R complex. This subunit is the molecular target of the approved biologics daclizumab (including daclizumab beta) and basiliximab. Another anti-CD25 mAb, inolimomab, has received orphan drug designation from the EMA, for the treatment of graft-versus-host disease. Phase 3 findings for this drug and indication are reported in [579] ...
Interleukin-2 receptor subunit β
(IL-2 receptor family)
IL2RB is a ligand binding component of the IL-2R and is required to elevate ligand affinity. It also a component of the IL-15R.
Interleukin-2 receptor subunit γ
(IL-2 receptor family)
IL2RG is a common signal transducing subunit shared by the receptors for several different cytokines, namely the IL-2 receptor heterotrimer, the IL-4 receptor type I, the IL-7 receptor, the IL-9 receptor, the IL-15 receptor and the IL-21 receptor.
Interleukin-31 receptor, α subunit
(IL-6 receptor family)
Interleukin 3 receptor, α subunit
(IL-3 receptor family)
This is the ligand binding subunit of the functional IL-3 receptor complex.
Anti-IL-3RA monoclonal antibodies (mAbs) are being investigated for the treatment of IL-3RA (CD123) positive hematological malignancies [21,323] ...
Interleukin-4 receptor subunit α
(IL-2 receptor family)
IL4R is the common ligand binding subunit shared by the IL-4 receptors type I (receptor for IL-4) and type II (receptor for IL-4 and IL-13). A gain-of-function mutation in IL4R has been associated with atopy, enhanced B cell isotype switching from mu to epsilon and therefore elevated IgE levels [249] ...
Interleukin 5 receptor, α subunit
(IL-3 receptor family)
This is the ligand binding subunit of the functional IL-5 receptor complex.
Interleukin-6 receptor, α subunit
(IL-6 receptor family)
IL6R polymorphisms are associated with asthma risk [186] ...
Interleukin-6 receptor, β subunit
(IL-6 receptor family)
This is the common signal transducing subunit shared by members of the IL-6 family of cytokine receptors [534] ...
Interleukin-7 receptor subunit α
(IL-2 receptor family)
This is the ligand binding subunit of the functional IL-7 receptor complex.
Effimmune are developing anti-IL7Rα monoclonal antibodies (e.g. OSE-127 [500] ...
Interleukin 9 receptor
(IL-2 receptor family)
The functional IL-9 receptor is a heterodimer of the ligand binding IL-9 receptor subunit and the interleukin 2 receptor γ (IL2RG) subunit. IL2RG is a common signal transducing subunit shared by the receptors for several different cytokines, including those for interleukin-2, -4, -7, and -15. ...
KIT proto-oncogene, receptor tyrosine kinase
(Type III RTKs: PDGFR, CSFR, Kit, FLT3 receptor family)
Stem cell factor (SCF) and its receptor KIT (c-KIT) play an essential part in mast cell biology. In addition to CSF/KIT-mediated regulation of mast cell development, proliferation and survival, KIT is also reported to be involved in the adhesion of mast cells to human airway epithelial cells (a homing and adhesion role), suggesting a mechanism that could be targeted for anti-asthmatic potential [221] ...
lymphotoxin β receptor
(Tumour necrosis factor (TNF) receptor family)
Interaction of the lymphotoxin β receptor (LTBR) with its ligand is required for the development and organization of the secondary lymphoid organs and is involved in chemokine release (reported to induce interleukin 8 gene expression [109] ...
macrophage stimulating 1 receptor
(Type X RTKs: HGF (hepatocyte growth factor) receptor family)
The role of RON in immuno-oncology is reviewed in [3] ...
membrane spanning 4-domains A2
(Fc epsilon receptors)
The protein product of the MS4A2 gene is the β subunit of the FCεRI. It has commonly known as FCER1B. The IgE-receptor (FCεRI), is a tetramer composed of an α, β, and 2 disulfide-linked γ chains expressed on the surface of mast cells and basophils that is crucial for mediating the allergic response. It has been suggested that cytoplasmic FCER1B that is not associated with FCεRI complexes may act as a negative regulator of the signalling pathway to degranulation by sequestering important signalling partners such as the Lyn tyrosine kinase [462] ...
MER proto-oncogene, tyrosine kinase
(Type XI RTKs: TAM (TYRO3-, AXL- and MER-TK) receptor family)
Mer plays a critical role in regulating self-tolerance mediated between apoptotic cells, dendritic cells, and T cells [47,649] ...
MET proto-oncogene, receptor tyrosine kinase
(Type X RTKs: HGF (hepatocyte growth factor) receptor family)
The leucine-rich repeat (LRR)-containing protein InlB of Listeria monocytogenes is reported to mediate bacterial entry in to non-phagocytic host cells by binding to the MET proto-oncogene, receptor tyrosine kinase (MET, or hepatocyte growth factor receptor, HGFR) [64] ...
NLRC3
(NOD-like receptor family)
NLRC3 is an intracellular pattern recognition receptor of the innate immune system. It has been shown to directly interact with and inhibit the type I interferon response of the intracellular DNA sensor STING to cytosolic DNA, cyclic di-GMP (c-di-GMP), and DNA viruses [395,718] ...
NLRC4
(NOD-like receptor family)
As part of the innate inflammatory response to invading mobile bacteria, NLRC4 (Ipaf) in macrophages induces a pro-inflammatory response upon detection of cytosolic bacterial flagellin. In contrast, extracellular bacterial flagellin is detected by TLR5 [414] ...
NLRC5
(NOD-like receptor family)
NLRC5 is an intracellular pattern recognition receptor mediating an innate immune response to viral infection [439] ...
NLRP1
(NOD-like receptor family)
NLRP1 is a cytosolic sensor of bacterial infection and regulator of the resulting innate immune response [106] ...
NLRP10
(NOD-like receptor family)
NLRP10 is an intracellular pattern recognition receptor (PRR) that has apoptotic and anti-inflammatory functions [273] ...
NLRP3
(NOD-like receptor family)
NLRP3 is a component of the NLRP3 inflammasome, a protein complex which activates caspase-1, and plays an important role in the regulation of inflammation and apoptosis (pyroptosis). Drug-like NLRP3 inhibitors are under investigation as novel therapeutics for the treatment of autoinflammatory diseases and neuroinflammation, as an alternative to anti-IL-1 therapies such as , and [32,396] ...
NLRP7
(NOD-like receptor family)
NLRP7 is an intracellular pattern recognition receptor (PRR). It is a member of the NACHT, LRR and PYD domains-containing protein (NALP) subfamily of PRRs. The presence of NALPs in inflammasomes underlies their involvement in regulating proinflammatory caspases (esp. caspase 1) ...
NLRX1
(NOD-like receptor family)
NLRX1 is an intracellular pattern recognition receptor that plays a role in host immunity to certain bacterial infections.
nucleotide binding oligomerization domain containing 1
(NOD-like receptor family)
NOD1 is an intracellular pattern recognition receptor that initiates an immune response to bacterial molecules containing a D-glutamyl-meso-diaminopimelic acid (iE-DAP) moiety.

Mutations in NOD proteins are implicated in various inflammatory diseases associated with aberrant NF-κB activ ...
nucleotide binding oligomerization domain containing 2
(NOD-like receptor family)
NOD2 is an intracellular pattern recognition receptor that initiates an immune response to bacterial molecules containing muramyl dipeptide (MDP).

Mutations in NOD proteins are implicated in various inflammatory diseases associated with aberrant NF-κB activity; NF-κB being a major ...
Oncostatin M-specific receptor, β subunit
(IL-6 receptor family)
Oncostatin M-specific receptor, β subunit (OSMR) is a component of two functional heterodimeric receptor complexes:
1. OSMR+ interleukin-6 receptor, β subunit (IL6ST) forms the receptor for oncostatin M
2. OSMR+ interleukin-31 receptor, α subunit forms the recept ...
osteoprotegerin
(Tumour necrosis factor (TNF) receptor family)
The protein product of the TNFRSF11B gene, osteoprotegerin, acts as a soluble decoy receptor for RANK ligand (RANKL) and for TRAIL. Experimental evidence links the RANK/RANKL signalling pathway with the inflammatory activation of microglial cells relevant in the development of infection-induced perinatal brain injury [307] ...
OX40
(Tumour necrosis factor (TNF) receptor family)
The OX40/OX40L pair is involved in late T-cell costimulatory signalling and both are transiently expressed following antigen recognition. Blocking OX40/OX40L is reported to prevent the development of disease in in vivo autoimmune and inflammatory disease models [665] ...
receptor activator of NF-kappa B
(Tumour necrosis factor (TNF) receptor family)
RANK is the receptor for RANK-ligand (RANKL). It is associated with immune cell function and lymph node development, in addition to bone remodeling and repair, thermal regulation, and mammary gland development. Signals to NF-κB and JNK via TRAF adaptor proteins.
RTP Type C
(Receptor tyrosine phosphatase (RTP) family)
CD45 is a high molecular weight cell surface glycoprotein expressed by cells of hematopoietic origin. Alternate transcripts lead to expression of isoforms that differ in their extracellular (ligand binding) domain (potentially facilitating differential and/or cell type specific biological functions [151] ...
single Ig and TIR domain containing
(Immunoglobulin-like family of IL-1 receptors)
IL-1R8 has been identified as a natural killer (NK) cell checkpoint that is involved in regulating NK cells' anti-viral and anti-tumour effector functions [419] ...
TACI
(Tumour necrosis factor (TNF) receptor family)
TACI is a lymphocyte-specific TNF superfamily receptor expressed on B cells. Endogenous ligands include APRIL, BAFF and CAML. Defects in the function of TACI can underlie immunodeficiencies and autoimmune diseases. TACI ligands are molecular targets of approved and investigational biologics that are ...
TEK receptor tyrosine kinase
(Type XII RTKs: TIE family of angiopoietin receptors)
In inflammation, angiopoietin-2 (ANG2) antagonism of TIE2 initiates a positive feedback loop via forkhead box O1 (FOXO1) activation, which drives further ANG2 expression and enhances vascular remodeling and leakage [311] ...
TLR1
(Toll-like receptor family)
TLR1/2 heterodimers detect and respond to bacterial triacyl lipopeptides [630] ...
TLR10
(Toll-like receptor family)
To date, ligands and biological functions of human TLR10 remain unclear. However, evidence suggests it plays a modulatory role with predominantly inhibitory (anti-inflammatory) effects [467] ...
TLR2
(Toll-like receptor family)
TLR1/2 and 2/6 heterodimers detect and initiate an immune response to triacylated and diacylated [434] ...
TLR3
(Toll-like receptor family)
TLR3 is an endosomal anti-viral receptor [630] ...
TLR4
(Toll-like receptor family)
TLR4 selectively responds to bacterial endotoxin, Gram-negative bacterial lipopolysaccharides (LPS), and lipooligosaccharides (LOS) [59,502] ...
TLR5
(Toll-like receptor family)
TLR5 induces a pro-inflammatory response upon detection of extracellular bacterial flagellin from invading mobile bacteria [414] ...
TLR6
(Toll-like receptor family)
TLR6 forms heterodimers with TLR2 to detect a wide range of bacterial lipopeptides (LP) from bacterial cell membranes, and effect an immune response [181] ...
TLR7
(Toll-like receptor family)
TLR7 is an endosomal receptor detecting ssRNA [630] ...
TLR8
(Toll-like receptor family)
TLR8 is an endosomal receptor detecting ssRNA [630] ...
TLR9
(Toll-like receptor family)
TLR9 is an endosomal receptor detecting viral and bacterial CpG DNA and genomic DNA from some protozoan species [630] ...
tumor necrosis factor receptor 1
(Tumour necrosis factor (TNF) receptor family)
We have included TNFR1 in GtoImmuPdb based on it being a receptor for lymphotoxin-α, a cytotoxic protein performing a variety of important roles in immune system development and regulation [225,444] ...
tumor necrosis factor receptor 2
(Tumour necrosis factor (TNF) receptor family)
TNFR2 is a receptor for lymphotoxin-α, and the membrane form of tumour necrosis factor (TNF). It plays a variety of important roles in immune system development and regulation [225,444] ...
TWEAK receptor
(Tumour necrosis factor (TNF) receptor family)
The protein product of the TNFRSF12A gene (fibroblast growth factor-inducible 14, or TWEAK receptor) is a receptor for the endogenous ligand TNF-like weak inducer of apoptosis (TWEAK). TWEAK receptor expression is upregulated in response to tissue injury. TWEAK receptor activation results in modulation of expression of NF-κB-regulated genes associated with the resolution of tissue damage. Because of its proinflammatory signalling profile the TWEAK receptor/TWEAK system has been implicated in a number of pathologies, and is therefore considered a potential drug target for conditions including muscle atrophy, cerebral ischaemia [229] ...
Transporters
GtoPdb receptor name (family) Process Association Comments GO Associations Immunopharmacology Comments
NRAMP1
(SLC11 family of proton-coupled metal ion transporters)
NRAMP1 / SLC11A1 appears to be involved in macrophage antimicrobial action against intracellular pathogens, and although its precise mechanism is not fully resolved, evidence indicates its involvement in the activation of phagocytes and synthesis of proinflammatory cytokines. Polymorphisms in the human SLC11A1 gene have been associated with susceptibility to several infections [73,583,586] ...
Other Protein Targets
GtoPdb receptor name (family) Process Association Comments GO Associations Immunopharmacology Comments
absent in melanoma 2
(Absent in melanoma (AIM)-like receptors (ALRs))
AIM2 primarily senses cytosolic DNA and initiates formation of an inflammasome to drive IL-1β cleavage and secretion.
advanced glycosylation end-product specific receptor
(Immunoglobulin like domain containing proteins)
RAGE is a single chain, membrane bound immunoglobulin type protein [438,551,688] ...
B7-H3 (CD276)
(Other immune checkpoint proteins, CD molecules)
B7-H3 is an immunoregulatory receptor involved in T cell activation and IFN-γ production [114,166] ...
baculoviral IAP repeat containing 2
(Inhibitors of apoptosis (IAP) protein family)
Cellular inhibitors of apoptosis proteins BIRC2 and BIRC3 are required for efficient caspase-1 activation by the inflammasome [331] ...
baculoviral IAP repeat containing 3
(Inhibitors of apoptosis (IAP) protein family)
Cellular inhibitor of apoptosis proteins (cIAPs) suppress apoptosis thereby promoting cell survival, and participate in the immune response (e.g. negative regulation of the necrosome, inflammasome and ripoptosome. In asthma, cIAPs extend the survival of neutrophils, macrophages and eosinophils, prolonging the inflammation. The minor alleles of single nucleotide polymorphisms in BIRC3 are shown to correlate with reduced numbers of circulating eosinophils and neutrophils, suggesting a protective effect against the development of asthma[533] ...
BCL2 apoptosis regulator
(B-cell lymphoma 2 (Bcl-2) protein family)
The role of Bcl-2 family members in immunity and disease is reviewed in [167] ...
Bcl-2-like 1
(B-cell lymphoma 2 (Bcl-2) protein family)
The role of Bcl-2 family members in immunity and disease is reviewed in [5] ...
BCL6 transcription repressor
(BTB (POZ) domain containing TFs)
BCL6/corepressor complexes are important for the formation of germinal centers and differentiation and proliferation of lymphocytes. Oncogenic mutations in BCL6 lead to the development of diffuse large B-cell lymphoma cells from germinal center B cells. Disruption of BCL6/corepressor complex formation by pharmacological inhibitors has therefore been identified as a novel drug mechanism with potential for the treatment of autoimmune diseases and cancer [95,103] ...
butyrophilin subfamily 3 member A1
(Butyrophilin and butyrophilin-like proteins)
Vγ2Vδ2 (a.k.a. Vγ9Vδ2) T cells bridge the gap between innate and adaptive immunity and play roles in microbial immunity and tumour immunity [423] ...
CD1d molecule
(CD molecules)
CD1d is a lipid-binding MHC class I-like protein that is expressed by dendritic cells. CD1d presents self and microbial lipid/glycolipid antigens to unconventional T cells known as invariant natural killer T (iNKT) cells [118,674] ...
CD2
(CD molecules)
CD2 is a cell surface glycoprotein expressed on most human T cells and natural killer (NK) cells [692] ...
CD28
(Other immune checkpoint proteins, CD molecules)
CD28 is expressed on the surface of T cells and is required for the co-stimulatory signal essential for the activation, proliferation and survival of T cells, and Th2 cell development. CD28 acts in concert with the T cell receptor to stimulate cytokine release (promotes IL-2 production). CD28 binds the the B7 proteins CD80 and CD86 on the surface of antigen presenting cells to effect a co-stimulatory signal to T cells. In contrast, CTLA-4 delivers a co-inhibitory signal via CD80/CD86 [11] ...
CD33
(Other immune checkpoint proteins, Sialic acid binding Ig like lectins, CD molecules)
CD33 (SIGLEC3) is a myeloid cell I-type (Ig-type) lectin that binds glycans containing sialic acids [206] ...
CD38
(Abscisic acid receptor complex, CD molecules)
CD38 is a type II transmembrane glycoprotein, that is widely expressed on immune cells and is involved in cell adhesion and signal transduction. Its extracellular domain acts as an ectoenzyme, catalyzing the conversion of nicotinamide adenine dinucleotide (NAD+) into nicotinamide, adenosine diphosphate-ribose (ADPR), and cyclic ADPR. Expression of CD38 is tightly regulated during B-cell development and maturation [230] ...
CD3e
(CD molecules)
CD3e is a subunit of the T cell receptor (TCR)-CD3 complex that mediates T cell receptor signal transduction in response to antigen detection. The TCR complex contains a CD3γ chain (CD3G), a CD3δ chain (CD3D), and two CD3ε chains (CD3E), plus the TCR (that can be α/β, or γ/δ type in the subsets of T cells named after the TCR they express) and the ζ-chain (zeta-chain).

CD3e plays a crucial role in T cell development, highlighted by the discovery that defects in CD3e cause severe immunodeficiency [154,587] ...
CD4
(CD molecules)
CD4 is being targeted for clinical utility in inflammatory diseases like rheumatoid arthritis (RA), neoplasms derived from T helper cells (T cell lymphomas and related malignancies), and for anti-HIV potential. Depending on the design of CD4 targeting antibodies, they can produce immunosuppressive effects via activation of Tregs and induction of tolerance, block HIV binding to CD4 to prevent HIV infection, or induce depletion of CD4+ T cells by apoptosis, ADCC, or CDC [319,643] ...
CD47
(CD molecules)
CD47 belongs to the immunoglobulin superfamily and is reported to bind membrane integrins and the ligands thrombospondin-1 (TSP-1) and signal-regulatory protein alpha (SIRPα). It is a ubiquitously expressed membrane protein that is a 'marker of self', and which is involved in self tolerance. Binding to SIRPα produces an anti-phagocytic signal. CD47 expression is hijacked by cancer cells to evade immune surveillance and macrophage-mediated removal. Anti-CD47 monoclonal antibodies are being investigated as novel immuno-oncology agents [373] ...
CD6
(CD molecules)
CD6 is a co-stimulatory molecule, predominantly expressed on lymphocytes and associated with autoimmune responses. CD6 interacts with activated leucocyte-cell adhesion molecule (ALCAM/CD166), found on antigen presenting cells. This interaction induces the production of proinflammatory cytokines [430] ...
CD74
(CD molecules)
CD74 is a type II transmembrane glycoprotein which associates with the MHC class II α and β chains and directs the transport of class II molecules to lysosomal and endosomal compartments [134] ...
CD80
(Other immune checkpoint proteins, CD molecules)
CD80 (B7-1) is expressed on dendritic cells and activated B cells and monocytes. It is required to provide a costimulatory signal necessary for T cell activation and survival. CD80 works in concert with CD86 to prime T cells. CD80 binds CD28 and CTLA-4 on T cells. It is the interaction with CTLA-4 t ...
CD86
(Other immune checkpoint proteins, CD molecules)
CD86 (B7-2) is a type I membrane immunoglobulin. It is expressed on antigen-presenting cells and in association with CD80 provides the costimulatory signal necessary for T cell activation and survival. CD86 interacts with CD28 or CTLA-4 on T cells. It is the interaction with CTLA-4 that is targeted ...
chitinase 3 like 1
(Chitinase-like proteins)
CHI3L1 is recognised as a proinflammatory mediator in the development and progression of Th2 inflammation, such as in allergic reactions [89] ...
claudin 18
(Claudins)
Claudin-18.1 is expressed exclusively in the tight junctions of lung epithelia. Claudin-18 deficiency has been identified as a contributor to airway epithelial barrier dysfunction and asthmatic reactions to air-borne antigens [602] ...
CREB binding protein
(Non-enzymatic BRD containing proteins)
CBP30, a selective CBP/p300 bromodomain inhibitor, suppresses human Th17 responses. PMID: 26261308 ...
C-type lectin domain family 4 member A
(C-type lectin-like receptors (CLRs))
CLEC4A is an pattern recognition receptor and immunoreceptor that functions in cell adhesion, cell-cell signalling, glycoprotein turnover, and plays roles in inflammation and the immune response. It contains a immunoreceptor tyrosine-based inhibitory motif (ITIM) in its cytoplasmic domain.
C-type lectin domain family 4 member E
(C-type lectin-like receptors (CLRs))
Mincle is an FcRγ-associated membrane receptor involved in initiating the innate immune response upon recognition of endogenous and exogenous ligands including Sin3A-associated protein (SAP130), α-mannan on fungal cell walls and mycobacterial cord factor (trehalose-6,6′-dimycolate (TDM)) [78] ...
C-type lectin domain family 6 member A
(C-type lectin-like receptors (CLRs))
Dectin-2 is involved in initiating the innate immune response upon recognition of high mannose structures on fungal cell walls. It associates with the ITAM-containing FcRβ adaptor and signals through the Syk, PKCδ, and CARD9-Bcl10-MALT1 pathways to promote cytokine production in response ...
C-type lectin domain family 7 member A
(C-type lectin-like receptors (CLRs))
Dectin-1 is a pattern recognition receptor involved in initiating the innate immune response upon recognition of various β(1,3)-linked and β(1,6)-linked glucans from fungi and plants. It mediates phagocytosis and the production of inflammatory mediators [77] ...
E1A binding protein p300
(Non-enzymatic BRD containing proteins)
CBP30, a selective CBP/p300 bromodomain inhibitor, suppresses human Th17 responses. PMID: 26261308 ...
Fc fragment of IgA receptor
(Immunoglobulin like domain containing proteins, CD molecules)
FcαRI is the cognate receptor for immunoglobulin A (IgA). In humans, IgA is predominantly expressed in the intestine, where it is important for maintaining mucosal homeostasis. IgA serves as a first-line defence to protect the gut epithelium from pathogens and enteric toxins [398,474] ...
heat shock protein 90 alpha family class B member 1
(Heat shock proteins)
HSP90AB1 chaperones both JAK2 and PRKCE, and by ensuring proper folding of these kinase proteins it is involved in the phosphorylation/activation of STAT1 [122] ...
heat shock protein 90 beta family member 1
(Heat shock proteins)
HSP90B1 is an endoplasmic reticulum chaperone required for proper folding and cell surface export of newly synthesized Toll-like receptor and integrin (CD11a, CD18 and CD49d) proteins. In its absence TLR responses are ablated, and there is no innate response to microbial stimuli [519] ...
immunoglobulin heavy constant epsilon
(Immunoglobulins)
IgE is being investigated as a molecular target in allergic inflammatory conditions such as asthma, allergic rhinitis and chronic spontaneous urticaria. One anti-IgE monoclonal, omalizumab, has already been approved for use in patients with asthma or chronic spontaneous urticaria. Omalizumab binds t ...
interferon gamma inducible protein 16
(Absent in melanoma (AIM)-like receptors (ALRs))
IFI16 is a sensor for cytosolic DNA which induces type I interferon production via activation of the IRF3/NFκB pathway.
kelch like ECH-associated protein 1
(Kelch-like proteins)
Transcription of many important detoxification enzymes is regulated by the Nrf2 transcription factor, which is (negatively) regulated by interaction with KEAP1, and when activated by disengagement from KEAP1, enters the nucleus and binds genes with an antioxidant responsive element (ARE) in their promoter sequences. Nrf2-responsive genes play important roles in the cellular defense system, in the regulation of the response to oxidative stress, and facilitate detoxification, antioxidant, cytoprotective and anti-inflammatory functions. Small molecule drug-like compounds that inhibit the KEAP1-Nrf2 protein-protein interaction (a.k.a. Nrf2 activators) are being developed for their potential anti-inflammatory action. The approved MS prodrug was reported to exploit this molecular mechanism, although more recent evidence suggests that its effects may be Nrf2 independent [558] ...
LAG3 (CD223)
(Other immune checkpoint proteins, CD molecules)
Membrane-bound LAG3 (CD223) is a T cell inhibitory co-receptor and immune checkpoint being investigated as a cancer immunotherapeutic target [20,219] ...
leucine rich repeat containing 32
(Leucine-rich repeat proteins)
GARP is expressed on the surface of T regulatory (Treg) cells and binds latent (inactive) TGF-β1. GARP is also involved in the activation of TGF-β1 [138] ...
leukocyte immunoglobulin like receptor A4 (CD85g)
(CD molecules)
LILRA4 (CD85g) is a member of the activating leukocyte immunoglobulin like receptor (LILRA) family (HGNC family 1181). It is involved in activation of eosinophils and homeostatic regulation of the innate immunity of plasmacytoid dendritic cells (pDCs) [94] ...
leukocyte immunoglobulin like receptor B1 (CD85j)
(CD molecules, Other immune checkpoint proteins)
LILRB1 (CD85j) is a member of the inhibitory leukocyte immunoglobulin like receptor (LILRB) family (HGNC family 1182). It acts as an inhibitory immune checkpoint for B cell function. Ligands identified for LILRB include native MHC class I proteins, some HLA molecules, pathogen-derived ligands (e.g. from CMV, Dengue virus and some bacteria) and host immunomodulatory proteins such as S100 calcium binding protein A9 (S100A9; P06702; which also binds TLR4 and RAGE) [82] ...
lymphocyte antigen 96
(Lymphocyte antigens)
LY96 (MD2) is a binding partner of Toll-like receptor 4 (TLR4), required to initiate an innate immune response to bacterial lipopolysaccharide (LPS). The signaling complex also contains CD14 co-receptor [315] ...
MALT1 paracaspase
(Immunoglobulin like domain containing proteins)
MALT1 inhibition is considered a tractable mechanism for the treatment of severe autoimmune diseases. The MALT1 inhibitory action of (a.k.a. mepazine) is reported to be effecacious in the mouse experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis [409] ...
myeloid cell nuclear differentiation antigen
(Absent in melanoma (AIM)-like receptors (ALRs))
MNDA can be detected exclusively in nuclei of hematopoietic cells of the monocyte lineage. Expression is induced by interferon α [70] ...
neural cell adhesion molecule 1 (CD56)
(CD molecules)
CD56 is expressed by neurons, glia, skeletal muscle and natural killer (NK) cells. The CD56bright NK cell subset, predominantly present in secondary lymphoid tissues, are capable of high levels of cytokine production, are enriched at inflammatory sites [150] ...
notch receptor 1
(Notch receptors)
NOTCH1 and its ligand Delta-like 4 (DLL4) play a dominant role in mediating the effects of Notch signaling in T cells during Graft-versus-host disease (GvHD). Anti-NOTCH1 or anti-DLL4 antibodies controlled GvHD [625] ...
nuclear factor, erythroid 2 like 2
(Basic leucine zipper domain TFs)
NRF2 is included in GToImmuPdb as mutations in this gene have been reported in patients with IMDDHH, an inherited disease in which some of the symptoms arise from defective immune system function [266] ...
pyrin and HIN domain family member 1
(Absent in melanoma (AIM)-like receptors (ALRs))
PYHIN1 participates in the innate immune response to microbial DNA [163] ...
RAS guanyl releasing protein 1
(EF-hand domain containing proteins)
RAS guanyl releasing protein 1 (RASGRP1) functions as a diacylglycerol (DAG)-regulated nucleotide exchange factor. It activates Ras and the downstream Erk/MAP kinase cascade. RASGRP1 regulates the development, homeostasis and differentiation of T aand B cells [220,506,566] ...
signal transducer and activator of transcription 3
(STAT transcription factors)
STAT3 regulates the expression of a variety of genes in response to cytokines and growth factors (e.g. IFNs, EGF, IL-5, IL-6, HGF, LIF and BMP2) and plays important roles in several cellular processes, including cell growth and apoptosis. STAT3 is a crucial component of the JAK/STAT signalling pathway that is implicated in cancer and inflammation. STAT3 is frequently activated in cancers, where it downmodulates intrinsic immune surveillance of tumour cells. Phosphorylated (activated) STAT3 (pSTAT3) is a marker of poor cancer prognosis [704,710] ...
signal transducer and activator of transcription 6
(STAT transcription factors)
STAT6 plays a central role in exerting IL-4 mediated biological responses. The prosurvival activity of the Th2 cytokine IL-4 is mediated by STAT6-dependent transcription of the anti-apoptotic protein B-cell lymphoma-extra large (Bcl-XL). This mechanism explains the resistance to apoptosis that is observed epithelial tumours which produce IL-4 [618] ...
SIRPA (CD172a)
(CD molecules, Signal regulatory proteins)
SIRPα is an important inhibitory immune response regulator. In interaction with CD47, SIRPα controls an inhibitory innate immune checkpoint that provides an anti-phagocytic (do not eat) signal. SIRPα is predominantly expressed by macrophages. Laboratory work has established that SIRPα is expressed by a subset of intestinal dendritic cells (integrin CD103+ DCs) that are critical for maintaining intestinal (mucosal) immune system homeostasis. This subset of CD103+SIRPα+ DCs selectively activates Th17 cells and type 3 innate lymphoid cells (ILC3) [290,662] ...
stimulator of interferon response cGAMP interactor 1
(Other pattern recognition receptors)
STING functions as a major regulator of the innate immune response to viral and bacterial infections [378] ...
TIGIT
(Other immune checkpoint proteins, Immunoglobulin like domain containing proteins)
TIGIT is now considered as an alternate inhibitory immune checkpoint protein which may have potential immunotherapeutic potential, particularly in conditions refractory to more established PD-1 checkpoint inhibition. Given its presence on T cells and NK cells, TIGIT offers an intervention point for targeting both the adaptive and innate arms of the immune system. Clinical development of anti-TIGIT monoclonal antibodies is in preliminary stages. Combination therapies with existing immune checkpoint inhibitors are considered particularly promising. MTIG7192A (NCT02794571 ...
TIM3 (CD366)
(Other immune checkpoint proteins, CD molecules)
TIM3 is an immunoglobulin type protein expressed exclusively on the surface of differentiated Th1 cells [422] ...
V-set immunoregulatory receptor
(Other immune checkpoint proteins)
V-set immunoregulatory receptor (VSIR) is commonly referred to as VISTA in the literature corpus. This is an Ig superfamily (B7 family) protein that acts as an inhibitory immune-checkpoint molecule. In common with other T cell co-inhibitory receptors (e.g. CTLA-4, PD-1, TIM3, and LAG3) it is involved in maintaining peripheral tolerance [362] ...