title: A cross-sectional immunosurveillance study of anti-EPO antibody levels in CRF patients receiving epoetin alfa in 5 Ontario Renal Centers.
abstract: BACKGROUND
  Epoetin alfa (Eprex*; Johnson & Johnson, Manati, PR) has been used successfully to correct the anemia of chronic renal failure for more than 12 years. Anti-erythropoietin (anti-EPO) antibodies have been reported in a small number of patients, resulting in a blood disorder, pure red cell aplasia (PRCA). To evaluate the utility of a large-scale anti-EPO antibody screening program in patients with chronic kidney disease (CKD) administered epoetin alfa, a study involving 5 large renal centers in southern Ontario, Canada, was conducted.
  
  
  METHODS
  More than 1,500 hemodialysis, peritoneal dialysis, and predialysis patients were screened for the prevalence of anti-EPO antibodies by means of a radioimmunoprecipitation (RIP) assay. Serum samples were drawn and shipped to PPD Development (Richmond, VA) for the immunoprecipitation assay. Serum EPO levels also were measured. All samples that tested positive or borderline for antibodies were sent to MDS Pharma Services (Montreal, Canada) for the neutralization assay.
  
  
  RESULTS
  Of 1,531 samples tested, 1 patient tested low-positive and 3 borderline results were detected by means of RIP. PRCA previously was diagnosed in the patient with the low-positive antibody level; the patient was treated with cyclosporine and currently is being administered epoetin alfa with good response. The 3 patients with borderline antibody results manifested no clinical signs of PRCA. Neutralization assays performed on all 4 serum samples were negative for anti-EPO antibodies.
  
  
  CONCLUSIONS
  Results from this surveillance study show that the prevalence of antibody to EPO in patients with CKD administered epoetin alfa in 5 Canadian renal centers is low, and the value of a large-scale antibody screening program for PRCA cannot be justified.
authors.affiliation: Institute of Kidney Lifescience Technologies, Toronto, Ontario, Canada. diadochk@yahoo.ca
authors.forename: George
authors.initials: G
authors.lastname: Wu
authors.forename: Arturo
authors.initials: A
authors.lastname: Wadgymar
authors.forename: Gordon
authors.initials: G
authors.lastname: Wong
authors.forename: Robert
authors.initials: R
authors.lastname: Ting
authors.forename: Bharat
authors.initials: B
authors.lastname: Nathoo
authors.forename: David
authors.initials: D
authors.lastname: Mendelssohn
authors.forename: Sanjay
authors.initials: S
authors.lastname: Pandeya
authors.forename: Daniel
authors.initials: D
authors.lastname: Sapir
authors.forename: Paul
authors.initials: P
authors.lastname: Tam
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000188:drug therapy / Q000209:etiology; D001323:Autoantibodies / Q000276:immunology*; D001327:Autoimmune Diseases / Q000188:drug therapy / Q000209:etiology* / Q000276:immunology; D003430:Cross-Sectional Studies; D016572:Cyclosporine / Q000627:therapeutic use; D000068817:Epoetin Alfa; D004921:Erythropoietin / Q000276:immunology* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000276:immunology* / Q000628:therapy; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D010530:Peritoneal Dialysis; D011159:Population Surveillance; D015531:Radioimmunoprecipitation Assay; D011994:Recombinant Proteins; D012010:Red-Cell Aplasia, Pure / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology* / Q000276:immunology; D006435:Renal Dialysis
chemical_list: D001323:Autoantibodies; D007166:Immunosuppressive Agents; D011994:Recombinant Proteins; D004921:Erythropoietin; D000068817:Epoetin Alfa; D016572:Cyclosporine