Epstein-Barr Virus Induced Gene-3 (EBI-3 or IL-27-beta) is a secreted glycoprotein belonging to the hematopoietin receptor family and related to the p40 subunit of IL-12. It was identified by its induced expression in B-lymphocytes in response to Epstein-Barr virus infection. EBI-3 forms heterodimers with p28 to form IL-27 and with p35 to form IL-35.  Both IL-27 and IL-35 have anti-inflammatory and regulatory activity.  Recombinant Human EBI is a non-glycosylated  polypeptide chain consisting of 209 amino acids with a molecular weight of 23.3 kDa.