IL-28A is distantly related to type I interferons and the IL-10 family. Expression of IL-28A is induced by viral infection which interacts with a heterodimeric class II cytokine receptor that consists of interleukin 10 receptor, beta (IL10RB) and interleukin 28 receptor, alpha. IL-28A exhibits common features with type I IFNs such as antiviral activity, antiproliferative activity and in vivo antitumor activity. They act similarly to IFNs, but are less effective generally and have activity in a more limited range of cell lines. IL-28A induces ELR (-) CXC chemokine mRNA in human peripheral blood mononuclear cells, in an IFN-gamma-independent manner. It is able to generate tolerogenic DCs, an activity that could thwart IFN-beta functions. IL-2