title: Diamond-Blackfan syndrome: evidence against cell-mediated erythropoietic suppression.
abstract: The profound anemia of Diamond-Blackfan syndrome (DBS) is due to marrow red cell failure, but the pathogenesis is not understood. Studies by others indicated cell-mediated erythropoietic suppression in this condition. To explore this mechanism further, Ficoll-Hypaque--separated peripheral blood lymphocytes (PBL) from four anemic untreated patients with DBS, or from normals were cocultured with control marrow in vitro and the growth of erythropoietin-responsive stem cell colonies (CFU-E) was dermined. CFU-E numbers obtained from cultures with added normal PBL were not significantly different from the number without PBL. Similarly, CFU-E from cultures with added DBS PBL were not significantly different from the number without PBL (215 versus 220, 229 versus 220 and 84 versus 60, 74 versus 94/10(5) cells, respectively). Mixing marrows from a control and one DBS patient in ratios of 2:1, 1:1, or 1:2 prior to culture failed to disclose a decrease of colony growth. We could not show cellular inhibition of erythropoiesis in these patients with DBS. The mechanism of anemia in this disorder remains an open question.
mesh_terms: D001854:Bone Marrow Cells; D002478:Cells, Cultured; D002675:Child, Preschool; D004913:Erythrocytes, Abnormal; D004921:Erythropoietin / Q000276:immunology*; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D007165:Immunosuppression Therapy; D007223:Infant; D008297:Male; D013577:Syndrome
chemical_list: D004921:Erythropoietin