Interleukin IL-27 (IL-27) is a heterodimeric cytokine belonging to the IL-12 family that is composed of two subunits,Epstein- Barr virus-induced gene 3 (EBI3), a 33-kDa glycosylated protein, and IL-27p28, a 28-kDa peptide. IL-27 is an early product of activated antigen-presenting cells and drives rapid clonal expansion of naïve but not memory CD4+ T cells. The effects of IL-27 are eliciting by its interaction with a specific cell surface receptor complex composed of two proteins known as WSX-1 (TCCR) and gp130. IL-27 has both pro- and anti-inflammatory properties.