title: Immunogenicity of recombinant human erythropoietin in Korea: a two-year cross-sectional study.
abstract: Immunogenicity of erythropoietin (EPO) is related with pure red cell aplasia (PRCA). We sought to determine the prevalence of antibody (Ab)-mediated PRCA in Korea and threshold diagnostic criteria by dual parameters: Ab titer and neutralizing activity. This study was a multi-center, cross-sectional study for two years. In the first year study (1 YS), 209 samples suspected to be EPO resistance were collected. In the second year study (2 YS), all the patients who consented to participate (N = 946) were enrolled. In 1 YS, we found three and six serum samples that were positive and borderline for anti-EPO Abs, respectively. The first three patients had neutralizing activity (NT) and were diagnosed as PRCA. In 2 YS, seven patients were anti-EPO positives and six had borderline levels. Among them, one patient with NT was diagnosed as PRCA and one with NT as aplastic anemia. The prevalence of PRCA was 0.106%. The correlation analysis of the 22 patients who had anti-EPO Ab showed that dual crossed cut-off lines (anti-EPO Ab titer ≥ 40 ng/ml, % NT ≥ 25%) were able to clearly isolate red cell aplasia. We suggest novel diagnostic criteria for diagnosis and prediction of Ab-mediated PRCA with data from both Ab titer assays and NT bioassays.
authors.affiliation: Ilsan Hospital, National Health Insurance Cooperation, Goyang, Republic of Korea.
authors.forename: Sug-Kyun
authors.initials: SK
authors.lastname: Shin
authors.forename: Sung Jin
authors.initials: SJ
authors.lastname: Moon
authors.forename: Sung Kyu
authors.initials: SK
authors.lastname: Ha
authors.forename: Young-Il
authors.initials: YI
authors.lastname: Jo
authors.forename: Tae-Won
authors.initials: TW
authors.lastname: Lee
authors.forename: Young Sook
authors.initials: YS
authors.lastname: Lee
authors.forename: Yang-Wook
authors.initials: YW
authors.lastname: Kim
authors.forename: Dae Joong
authors.initials: DJ
authors.lastname: Kim
authors.forename: Jin Kuk
authors.initials: JK
authors.lastname: Kim
authors.forename: Tae-Hyun
authors.initials: TH
authors.lastname: Yoo
authors.forename: Kyu-Beck
authors.initials: KB
authors.lastname: Lee
authors.forename: Seung Ok
authors.initials: SO
authors.lastname: Choi
authors.forename: Ea Wha
authors.initials: EW
authors.lastname: Kang
authors.forename: Kang Wook
authors.initials: KW
authors.lastname: Lee
authors.forename: Sung-Jo
authors.initials: SJ
authors.lastname: Kim
authors.forename: Sang Kyum
authors.initials: SK
authors.lastname: Kim
authors.forename: Tae-Hwe
authors.initials: TH
authors.lastname: Heo
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D004921:Erythropoietin / Q000276:immunology*; D005260:Female; D006801:Humans; D007723:Korea; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins / Q000276:immunology
chemical_list: D011994:Recombinant Proteins; D004921:Erythropoietin