Effect of recombinant human erythropoietin on human IgE production in vitro

Abstract

Recombinant human erythropoietin enhanced spontaneous IgE production 200–300% enhance ment) in cultures of peripheral blood mononuclear cells (MNC) from atopic patients. In contrast, IgG and IgA production were only slightly enhanced (30–50% enhancement), and IgM production was not affected by erythropoietin. The enhancement of IgE production by erythropoietin was indirect since it required T cells and monocytes. However, erythropoietin effect was specific since enhancement was blocked by anti‐erythropoietin antibody but not by control antibody. Interleukin‐4 (IL‐4) also enhanced spontaneous IgE production from atopic MNC. However, the enhancing effect by erythropoietin is different from that by IL‐4, since the erythropoietin effect was not blocked by anti‐IL‐4 antibody, and conversely IL‐4 effect was not blocked by anti‐erythropoietin antibody. In contrast to the enhancing effect on atopic MNC, erythropoietin failed to induce IgE production in cultures of MNC from normal donors while IL‐4 induced IgE production from normal MNC. However, when normal MNC were pre‐incubated with IL‐4. erythropoietin enhanced IgE production from IL‐4‐pre‐incubated MNC. Moreover. B cells separated from IL‐4‐pre‐incubated MNC produced IgE which was enhanced by erythropoietin. However, this effect required T cells and monocytes. These results indicate that erythropoietin could regulate ongoing IgE production in vitro by T cell‐ and monocyte‐dependent mechanisms. Copyright © 1991, Wiley Blackwell. All rights reserved