IL-27, a heterodimer protein, belongs to the IL-12 cytokine family. IL-27 is composed of Epstein-Barr virus-induced gene 3 (EBI3) a 34 kD glycoprotein that is related to the p40 subunit of IL-12; and p28, a 28 kD glycoprotein that is related to the p35 subunit of IL-12 and p19 subunit of IL-23.IL-27 triggers expansion of antigen-specific naïve CD4+ T cells, promotes polarization of Th1 cells, and inhibits the development of Th2 and Th17 cells. It is known that IL-27 is an early product of activated antigen-presenting cells (APCs). IL-27 plays an important role in regulating the activity of B and T lymphocytes.BioLegend's LEGEND MAX(TM) Mouse IL-27 Heterodimer ELISA Kit is a sandwich Enzyme-Linked Immunosorbent Assay (ELISA) with 96 well microtiter strip plates that are pre-coated with a capture antibody.This kit is specifically designed for the accurate quantitation of mouse IL-27 p28/EBI3 heterodimeric form from cell culture supernatant, serum, plasma and other biological fluids. This kit is analytically validated, with ready-to-use reagents.