IL-28B is a cytokine remotely related to type I interferons and the IL-10 family. Interleukin-28B, interleukin 28A (IL28A), and interleukin 29 (IL29) are 3 closely related cytokine genes which form a cytokine gene cluster on a chromosomal region mapped to 19q13. Expression of the cytokines encoded by these 3 genes can be induced by viral infection. All 3 cytokines interact with a heterodimeric class II cytokine receptor which consists of interleukin 10 receptor, beta (IL10RB) and interleukin 28 receptor, alpha (IL28RA). MW: 24 kDa, monomer, non-glycosylated. Purity > 95%