Assessment of the expression level of B-cell lymphoma 6 (BCL6) in peripheral blood CD38+ B lymphocytes in patients with common variable immunodeficiency (CVID)

Abstract

Background: Common variable immunodeficiency (CVID), the most common symptomatic primary immunodeficiency, is a heterogeneous set of immunological abnormalities including decreased serum levels of antibodies, and impaired antibody response to infections or vaccination. The syndrome includes impaired B-cell maturation, impaired somatic hypermutation, reduced numbers of circulating memory B cells, and absent or reduced plasma cells. B cell lymphoma 6 (BCL6) is a transcription factor which is important for the evolution and proliferation of B cells. This study aimed to investigate the expression of BCL6 in peripheral blood CD38+ B lymphocytes in patients with CVID. Methods: Blood samples were collected from 14 patients with CVID under substitutive immunoglobulin (Ig) therapy before immunoglobulin infusion and 14 normal controls. Then, peripheral blood mononuclear cells (PBMCs) were isolated using Ficoll-Hypaque density centrifugation. CD19+ B lymphocytes were purified from PBMCs by positive selection using B-cell isolation kit. Flow cytometery method was employed to determine the expression of the BCL6 in CD38+ B cells. Findings: The expression of BCL6 in CD38 +B lymphocytes was 1.51 and 0.58 in patients and healthy subjects, respectively; the difference was not statistically significant (P > 0.05). Conclusion: The results showed that there is no significant difference in the mean expression of BCL6 of the CD38+ B cells in patients with CVID, compared with control group. However, the average BCL6 expression of CD38+ B lymphocytes in patients was more than control group. © 2017, Isfahan University of Medical Sciences(IUMS). All rights reserved.