Fig. 4

Loss of immunoglobulin A (IgA) promotes pro-inflammatory intestinal T cell responses in high fat diet (HFD)-fed mice. Frequency (left) and absolute number (right) of a CD3⁺ T cells, b T cell subsets, c interferon-γ (IFNγ) and interleukin-17 (IL-17)-producing (T-helper type 1 (Th1) and Th17, respectively) CD4⁺ T cells, d IFNγ-producing CD8⁺ T cells in the distal small intestinal lamina propria (LP) of HFD-fed IgA^−/− compared to wild-type (WT) controls (n = 9 WT, 11 IgA^−/−, 4 experiments). e Frequency (left) and absolute number (right) of CD3⁺ T cells, f T cell subsets, g IFNγ- and IL-17-producing (Th1 and Th17, respectively) CD4⁺ T cells, h IFNγ-producing CD8⁺ T cells in colon LP of HFD-fed IgA^−/− compared to WT controls (n = 7–8 WT, 11–13 IgA^−/−, 4 experiments). Data are means ± SEM. * denotes p < 0.05, ** denotes p < 0.01, and *** denotes p < 0.001