Diazepam-binding inhibitor-related protein 1: a candidate autoantigen in acquired aplastic anemia patients harboring a minor population of paroxysmal nocturnal hemoglobinuria-type cells

Immune Pathophysiology of Aplastic Anemia

Acquired aplastic anemia (AA) is considered an immune-mediated disease because approximately 70% of AA patients improve with immunosuppressive therapy. However, little is known about the inciting antigens or the mechanisms responsible for the destruction of hematopoietic stem cells by immune system attack. Recent advances in immunologic techniques have promoted our understanding of the pathogenesis of AA and have provided evidence that AA is an organ-specific T-cell-mediated disease localized in the bone marrow. Moreover, antibody screening of patients' serum with a complementary DNA library derived from hematopoietic cells has identified several proteins as candidate autoantigens in AA.

Presence of anti-kinectin and anti-PMS1 antibodies in Japanese aplastic anaemia patients

While anti-kinectin antibodies are frequently found in aplastic anaemia (AA) patients from the US (39%), we detected antibodies in only three of 30 (10%) of Japanese AA cases. Additionally, population differences in anti-postmeiotic segregation increased 1 (PMS1) responses were seen, with detectable antibody in 10% Japanese and 0% US AA patients. In one of the Japanese AA patients with detectible anti-kinectin antibodies, the autoantibody disappeared coincidentally with the partial resolution of pancytopenia. These results support the hypothesis that the epidemiology of AA is heterogeneous and suggest that anti-kinectin autoantibody titre may serve as a surrogate maker for the disease activity of AA.