Regulation of Autoimmune Germinal Center Reactions in Lupus-Prone BXD2 Mice by Follicular Helper T Cells
Fig 5
IL-21-producing CXCR5+CD4+ T cells of BXD2 mice, not IL-17-producing CCR6+CD4+ T cells, provide B cell help for IgG production.
(A) CXCR5+ CD4+ T cells and CCR6+ CD4+ T cells were sorted and subjected to intracellular cytokine staining. (B) Quantitative RT-PCR analysis of Tfh or Th17 cell related gene expression in the CXCR5+ and CCR6+ CD4+ T cells from BXD2 mice (C) Naïve B cells (B220+IgD+GL7-) from BXD2 mice were co-cultured with CXCR5+ or CCR6+ CD4+ T cells from BXD2 mice for 7days. The total IgG levels were measured by ELISA (D) Different cytokine blocking reagents, isotype control antibody (Iso Hu-Fc), Rat anti mouse IL-17A antibody (α-IL-17A), or recombinant mouse IL-21 receptor Fc chimera (IL-21R-Fc) were added (10 μg/ml, every other day) into the cell culture described in (C) and the levels of total IgG were measured by ELISA. Data are represented as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, ###p < 0.001 comparing 10:10–10:5 ratio of B:T co-culture condition.