Intestinal IgA levels discriminate patients with and without CVID enteropathy. (a) Levels of total IgA in serum of CVID patients. (b) Expression of genes coding for IgA1, IgA2, IgM, IgG1, IgG2, IgG3, IgG4 in duodenal biopsies of CVID patients with enteropathy (n=6), noE-CVID (n=8) and Control subjects (n=7); *p<0.05; # p<0.1, one-sided t-test, comparing E-CVID to other groups, mean/SD shown. (c) Representative images of IgA immunohistochemistry in duodenal biopsies and quantitative analysis, *p<0.05; # p<0.1 Mann-Whitney one-sided test comparing E-CVID to other groups; cpm stands for counts per million.