CD210 is a 90-110 kD IL-10 receptor. It is a class II cytokine receptor expressed on thymocytes, T cells, B cells, NK cells, monocytes and macrophages. Ligand binding of CD210 induces Jak1 and Tyk, resulting in STAT1 and STAT3 activation. IL-10 receptor stimulation results in the inhibition of cytokine production and the costimulation of B cell proliferation and differentiation. The only known ligand for this receptor is IL-10.