Recognizes a protein of 16-27kDa, identified as human interferon-II) (IFN-(II). Its epitope maps between aa43-53 of the IFN-II) (total aa172). This MAb is specific for IFN-(II) and does not cross-react with IFN-(I). Epitopes of N27 and N39 MAb s are different and represent a good combination of antibodies to set up an ELISA assay for the quantitation of IFN-(II) after viral infections. The IFN- family consists of 24 or more genes or pseudo-genes. IFN-II) is one of the two distinct families (I and II) of human IFN-. The interferon are mainly produced by lymphocytes, monocytes, macrophages, and cell lines such as Namalwa and KG1 following induction by viruses, nucleic acids, and glucocorticoid hormones. They are involved in virus resistance on target cells, inhibition of cell proliferation, induction of cytokines and regulation of expression of MHC class I antigens.