Table 1.

Cytokine receptors (CR) and endogenous agonists and antagonists.

Receptor family	Agonists	Antagonists	CR type
IL-1 family
IL-1R1	IL-1α, IL-1β	IL-1Ra	Type 2
IL-1R2
IL-18	IL-18, IL-37
IL-33R	IL-33
IL-36R	IL-36α, IL-36β, IL-36γ	IL-36Ra
IL-2 family
IL-2R	IL-2	IL-1Ra	Type 1
IL-4R1	IL-4
IL-4R2	IL-13, IL-4
IL-7R	IL-7
IL-9R	IL-2	IL-1Ra
IL-13Rα2
IL-15R	IL-15
IL-21R	IL-21
IL-3 family
IL-3R	IL-3		Type 1
IL-5R	IL-5
GM-CSFR	G-CSF, GM-CSF
IL-3α	IL-3
IL-5Rα	GM-CSF
GM-CSFRα	GM-CSF
IL-6 family
IL-6R	IL-6	Type 1
IL-11R	IL-11
IL-27R	IL-27
IL-31R	IL-31
IL-6Rα	IL-6
IL-10 family
IL-10R	IL-10		Type 2
IL-20R	IL-19
IL-22Rα/20β	IL-20
IL-22Rα/10β	IL-22
IFN-λ	IFN-λ1, IFN-λ2, IFNλ3
IL-12 family
IL-12R	IL-12	A/IL-12B	Type 1
IL-23R	IL-12B/IL-23
IL-13 family
IL-3R	IL-3		Type 1
IL-5R	IL-5
GM-CSFR	c-CSF, GM-CSF
IL-3α	IL-3
IL-5α	IL-5
GM-CSFRα
IL-17 family
IL-17RA	IL-17A/IL-17F		Type 2
IL-17RB	IL-17B
IL-17RC	IL-17C
IL-17RD
IL-17RE	IL-17E
IL-25	IL-17B
TNF family
TNFR1	TNF
TNFR2	TNF
IFN family
IFN-R, type 1	IFN-α, IFN-β, IFN-κ, IFN-ω
IFN-R, type 2	IFN-γ

IL-1R type 2 is decoy receptor and binds IL-1α, IL-1β, and IL-receptor antagonist.

IL-1R family: possess immunoglobulin-like extracellular domains and an intracellular toll/IL-1R domain.

IL-2R: both α and β subunits bind ligand.

IL-6R: Ras/Raf/MAPK, PI 3 kinase/PKB.

IL-10: family of heterodimers.

IL-13R and IL-22Rα: there are also decoy receptors that bind IL-13 and IL-22.

IL-17 family: 6 ligands and 5 receptors.

Symbols α and β.

Heterodimers: IL-12A/IL-12B; IL-12B/IL-23.

Ra, receptor antagonist; TNF, tumor necrosis factor.