Phenotypically defined subpopulations of circulating follicular helper T cells in common variable immunodeficiency

Background Common variable immunodeficiency (CVID) is characterized by low immunoglobulin G and IgA/IgM, decreased switched memory B cells, impaired response to vaccine, and an increased susceptibility to infections and autoimmunity. TFH cells play an important role in germinal center reaction where it supports isotype switching, somatic hypermutation, generation of memory B cells, and differentiation of B cells to plasma cells. The objective was to study the distribution of three subsets of TFH cells and their relationship with autoimmune diseases associated with CVID. Methods TFH cells have been divided into TFH1 (interleukin 21 [IL‐21] and interferon γ), TFH2 (IL‐21 and IL‐4), and TFH17 (IL‐21 and IL‐17) cells. Mononuclear cells from 25 patients with CVID and age and gender‐matched controls were stained with various monoclonal antibodies (anti‐CD4 APC, anti‐CXCR5 FITC, anti‐CCR6 PerCP, and anti‐CXCR3 PE) and isotype controls and analyzed for TFH1 (CD4+CXCR5+CXCR3+CCR6−), TFH2 (CD4+CXCR5+CXCR3−CCR6−), and TFH17 (CD4+CXCR5+CXCR3−CCR6+) cells by multicolor flow cytometry. Twenty thousand cells were acquired and analyzed by FlowJo software. Statistical analysis of comparison of patients and healthy controls was performed by paired t test using PRISM 7 software. Results TFH2 and TFH17 cells subpopulations of TFH cells were significantly decreased (P