IMMUNOMODULATORY ACTION OF HUMAN RECOMBINANT ERYTHROPOIETIN IN MAN

Recent findings suggest that recombinant human erythropoietin (rhEpo) may have an immunomodulating action. We have studied the in vitro and in vivo effects of rhEpo on immune functions in man. Low pharmacologic al concentrations of the hormone inhibit T-cell activation and prolife ration, while higher ones are without that effect. The same Epo concen trations inhibit mitogen- and alloantigen-driven B-cell differentiatio n and immunoglobulin synthesis and, to a lesser extent, B-cell prolife ration. In vivo treatment with rhEpo causes an initial inhibition of T - and B-cell proliferation, but with prolonged administration improved responsiveness is observed. Our data support the notion that rhEpo ca n regulate immune functions, a fact of potential clinical application.