Table 1.
Biological activity of fish type II cytokines.
| Cytokine | Human homologue | Receptors | Known immune functions | references |
|---|---|---|---|---|
| IL-10, viral IL-10 | IL-10 | IL-10R1/CRFB12, IL-10R2/CRFB4 | Suppress immune responses, inhibit inflammation, promote T cell proliferation, memory B cells, and IgM production | [265,273,276] |
| IL-20L | IL19, IL-20, IL-24 | Not characterised | Not characterised | [200,258] |
| IL-22 | IL-22 | Not characterised | Activate antimicrobial peptide genes and antibacterial immunity | [277,278] |
| IL-26 | IL-26 | Not characterised | Not characterised | [242,250] |
| Group I IFN (IFN-a, d, e) | Type I IFN | IFNAR1/CRFB5, IFNAR2/CRFB1 | Induce expression of the antiviral effectors, promote apoptosis, regulate inflammation | [201,207,210,221,234] |
| Group II IFN (IFN-b, c, f) | Type I IFN | IFNAR1/CRFB5, IFNAR2/CRFB2 | Induce expression of the antiviral effectors, promote apoptosis | [207,210,221,223] |
| IFN-γ | Type II IFN | IFN-γR1/CRFB13, IFN-γR2/CRFB6 | Activate phagocytes, enhance antigen presentation, promote Th1 cytokine expression | [254,255,256,257] |
| IFN-γrel | Type II IFN | CRFB17, IFN-γR2/CRFB6 | Regulate anti-bacterial and antiviral immunity | [255,261] |