Determination of normal expression patterns of CD86, CD210a, CD261, CD262, CD264, CD358, and CD361 in peripheral blood and bone marrow cells by flow cytometry.

In 2010, new monoclonal antibodies were submitted to the 9th International Workshop on Human Leukocyte Differentiation Antigens, and there are few studies demonstrating normal expression patterns of these markers. Thus, the objective of this study was to determine the normal patterns of cell expression of CD86, CD210a, CD261, CD262, CD264, CD358, and CD361 in peripheral blood (PB) and bone marrow (BM) samples by flow cytometry. In the present study, CD86 was expressed only in monocytes and B lymphocytes in PB and in monocytes and plasma cells in BM. Regarding CD210a expression, in PB samples, monocytes and NK cells showed weak expression, while neutrophils, B and T lymphocytes, and basophils showed weak and partial expression. In BM samples, expression of CD210a was observed in eosinophils, monocytes, and B and T/NK lymphocytes. Weak expression of CD210a was also observed in neutrophilic cells and plasma cells. All B cell maturation stages had weak expression of CD210a except for immature B cells, which did not express this marker. In the present study, no cell type in PB samples showed positivity for CD261 and, in BM samples, there was very weak expression in neutrophilic series, monocytes, and B lymphocytes. Conversely, plasma cells showed positivity for CD261 with a homogeneous expression. For CD262, there was weak expression in monocytes, neutrophils, and B lymphocytes in PB samples and weak expression in monocytes, B lymphocytes, and plasma cells in BM samples. The evaluation of CD264 showed very weak expression in B cells in PB samples and no expression in BM cells. Very weak expression of CD358 was observed in neutrophils, monocytes, and B lymphocytes in PB and BM samples. In addition, in BM samples, plasma cells and T lymphocytes showed weak expression of CD358. In relation to the maturation stages of B cells, there was weak expression in pro-B cel, pre-B cell, and mature B cell. In the present study, it was possible to observe expression of CD361 in all cell types analyzed in PB and BM samples. The analyzed markers presented varied profiles of expression and, in some cases, these profiles were different from those observed in other studies. Further studies are needed to evaluate these molecules, mainly in relation to a possible application in the diagnosis of hematological malignancies or as new therapeutic targets for the treatment of hematological neoplasms or autoimmune diseases.