A B cell line from a patient with pure red cell aplasia produces an immunoglobulin that suppresses erythropoiesis.
A 4-year-old boy with pure red cell aplasia was investigated. Immunophenotypic analysis of peripheral blood lymphocytes revealed a marked increase of CD20+ cells, which fell from 25.9% in the active stage to 9.7% in remission. The plasma contained a suppressive activity against CFU-e and BFU-e formation by the patient's bone marrow cells, which disappeared when the disease went into remission. Prednisone (2 mg/kg/day) therapy was tried for 5 weeks, but produced no improvement. Subsequently, high-dose gamma-globulin therapy induced complete remission of anemia. A lymphoblastoid B cell line obtained from the patient before therapy produced a factor that suppressed erythropoiesis but not granulopoiesis. The suppressive activity resided in the immunoglobulin fraction and was adsorbed by an anti-immunoglobulin column. These results indicate that expansion of B cells producing an immunoglobulin which suppressed erythropoiesis was involved in the pathogenesis of the disease in this patient.
Nagasawa
M
M
Department of Pediatrics, Faculty of Medicine, Tokyo Medical and Dental University, Japan.
Okawa
H
H
Yata
J
J
D001402:B-Lymphocytes / Q000378:metabolism*; D002460:Cell Line; D002675:Child, Preschool; D004920:Erythropoiesis / Q000276:immunology*; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis* / Q000276:immunology; D016131:Lymphocyte Subsets / Q000276:immunology; D008297:Male; D010641:Phenotype; D012010:Red-Cell Aplasia, Pure / Q000276:immunology* / Q000628:therapy; D005719:gamma-Globulins / Q000627:therapeutic use
D007136:Immunoglobulins; D005719:gamma-Globulins