Effects of recombinant human interferon-gamma (Met-Gln form) on expression of Fc receptor and Ia-like antigen on human peripheral monocytes and lymphocytes: a comparative study with natural human interferon-alpha and -beta.

Abstract

The effects of recombinant human interferon (IFN) -gamma (Met-Gln form), having the same amino acid sequence as that of natural human IFN-gamma except for the N-terminal Met residue, on the expression of Fc receptor (FcR) and Ia-like antigen in human monocytes and lymphocytes were comparatively investigated with those of natural human IFN-alpha and -beta. IFN-gamma (Met-Gln form) increased dose-dependently the number of FcRs binding to anti-chicken red blood cell (CRBC) immunoglobulin G on monocytes and the number of monocytes bearing the FcR, whereas the two natural IFNs did not. IFN-gamma (Met-Gln form) also enhanced the expression of Ia-like antigen on monocytes but the natural IFNs did not. On the other hand, IFN-gamma (Met-Gln form) had no effect on the expression of the FcR and Ia-like antigen on lymphocytes or on antibody-dependent cell-mediated cytotoxic activity against CRBCs, as was also the case with the natural IFNs. These results indicate that IFN-gamma (Met-Gln form) has a potent ability to induce or enhance the expression of FcR and Ia-like antigen on human monocytes though IFN-alpha and -beta do not, whereas IFN-gamma (Met-Gln form) has no effect on the expression on human lymphocytes, like the natural IFNs.