Abstract
Recombinant human erythropoietin (rhEPO) treatment of hemodialyzed (HD) patients normalizes the altered phenotype of CD4(+) lymphocytes and restores the balance of Th1/Th2 cytokines. We decided to test how the presence of rhEPO in cell culture modulates cytokine production of CD4(+) lymphocytes in HD patients with stable hemoglobin level and expression of activation antigens of stimulated CD4(+) lymphocytes similar to those observed in healthy individuals. We also tested whether the presence of rhEPO in cell culture protects stimulated CD4(+) lymphocytes of HD patients from apoptosis. Peripheral blood mononuclear cells (PBMC) of HD patients were stimulated with an immobilized anti-CD3 antibody with or without addition of rhEPO. The percentage of apoptotic CD4(+) lymphocytes and the level of Th1/Th2 cytokines in culture supernatants were measured with flow cytometry. HD patients showed a decrease in the percentage of apoptotic CD4(+) cells after stimulation with the anti-CD3 antibody combined with rhEPO. The level of IFN-γ and IL-10 was increased while the level of TNF-α was decreased in the presence of rhEPO in cell culture from HD patients. These results confirm the role of rhEPO signaling in T lymphocytes of HD patients.