Abnormal expression of b10 cell frequencies: possible relation to pathogenesis and disease severity of aplastic anemia

OBJECTIVE: Aplastic anemia (AA) is an immune-mediated disease that destroys hematopoietic cells through activated T lymphocytes. B lymphocyte-mediated humoral immunity also plays an important role in the pathogenesis of AA. Regulatory B cell (Breg) subpopulation, which is defined as "B10", secretes interleukin 10 (IL-10). The objective of our experiment was to investigate whether the scale-down proportion of B10 cells in AA patients may play a key role in the pathogenesis. METHODS: A total of 38 AA patients (14 SAA patients and 24 NSAA patients) and 20 healthy control subjects were included. All subjects did not suffer from autoimmune diseases or any other diseases affecting the immune system, such as infectious diseases. Bone marrow mononuclear cells (PBMCs) were isolated and analyzed by Flow cytometry (FCM) and Immunofluorescence double-labeling assay. The relationship between the relative proportions of B10 and ProB10 and their associations to AA, as well as disease severity, were assessed by common clinical indicators and then examined. RESULTS: Our analyses revealed AA patients had significantly lower proportions of peripheral B10 and B10pro compared to healthy controls. SAA patients had a substantially lower percentage of B10 cells and B10pro cells compared to NSAA patients. In addition, B10 cells and B10pro cells were negatively correlated with absolute neutrophil counts, hemoglobin levels and platelet, and absolute reticulocyte counts in AA patients. CONCLUSIONS: The present study attempted to elucidate the potential role of the scale-down proportion of B10 cells in the pathogenesis of AA.