Mouse Il10 is the prototypic member of the IL-10 cytokine family, including IL-10, IL-19, IL-20, IL-22 (IL-TIF), IL-24 and IL-26. Many viruses encode viral members of the IL-10 family, such as Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV).Its main function is inhibiting the synthesis of a number of cytokines, including IFN-gamma, IL-2, IL-3, TNF and GM-CSF produced by activated macrophages and by helper T-cells. Although human and mouse IL-10 are 81% identical at the nucleotide and amino acid level, mouse IL-10 is species-specific and does not act on human cells. Interestingly, Human IL-10 is active on mouse cells.