Detection of anti-erythropoietin antibodies in haemodialysis patients treated with recombinant human-erythropoietin

An enzyme-immunoassay was developed to evaluate the presence of anti-erythropoietin antibodies in:plasma samples obtained from renal failure patients treated with recombinant human erythropoietin (rh-EPO). The assay was specific and reproducible. Normal donors had no antibodies to EPO, while 67% of treated patients were positive to the assay. While the specificity of anti-EPO IgG antibodies was high, their affinity for the antigen was low. This finding can be explained by the very small differences in the structure of rh-EPO compared to that of natural EPO. The assay described could be useful in evaluating the long-term effects of rh-EPO treatment on the control of anaemia in renal failure patients. (C) 2000 Academic Press.