Figure 1. IgA deficiency induces ileitis (IMAGE) Tokyo Medical and Dental University Caption The small intestine is composed of duodenum, jejunum and ileum (left). IgA deficiency causes distortion of the gut microbiota, especially in the ileum, and inflammatory cytokines are secreted from T cells, resulting in in inflammation of the ileum (right). Credit Department of Immunology, TMDU Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.