Premium
Autoantibodies to erythropoietin receptor in patients with immune‐mediated diseases: relationship to anaemia with erythroid hypoplasia
Author(s) -
Hara Akinori,
Furuichi Kengo,
Higuchi Masato,
Iwata Yasunori,
Sakai Norihiko,
Kaneko Shuichi,
Wada Takashi
Publication year - 2013
Publication title -
british journal of haematology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.907
H-Index - 186
eISSN - 1365-2141
pISSN - 0007-1048
DOI - 10.1111/bjh.12105
Subject(s) - erythropoietin receptor , autoantibody , antibody , erythropoietin , immunology , medicine , receptor , erythropoiesis , bone marrow , immune system , biology , anemia
Summary The prevalence, clinical associations and pathogenic role of newly identified autoantibodies to the erythropoietin receptor ( EPOR ) in patients with anaemia were investigated. Sera from 203 patients with immune‐related or chronic kidney diseases were screened for anti‐ EPOR antibodies by enzyme‐linked immunosorbent assay, and antibody specificity was evaluated by immunoprecipitating EPOR from AS ‐ E 2 cells using purified immunoglobulin ( I g) fractions. In addition, the pathogenic role of anti‐ EPOR antibodies was determined by examining their inhibitory effects on AS ‐ E 2 cell proliferation. Clinical findings were compared between patients with and without anti‐ EPOR antibodies, in all patients and those with systemic lupus erythematosus ( SLE ). Serum anti‐ EPOR antibodies were detected in 52 patients. Purified I g G or I g M fractions from anti‐ EPOR antibody‐positive sera immunoprecipitated EPOR and inhibited the EPO ‐dependent proliferation of AS ‐ E 2 cells in a dose‐dependent manner. Anti‐ EPOR antibodies were associated with low haemoglobin concentrations and reticulocytopenia in all patients enrolled and those with SLE . Further, there was a negative correlation between the levels of anti‐ EPOR antibodies and the number of bone marrow erythroblasts in patients who underwent bone marrow examinations. These findings suggest that EPOR autoantibodies are present in a subset of patients with anaemia and that impaired erythropoiesis can be mediated by anti‐ EPOR antibodies, which functionally neutralize EPO activity.