CD79A and inflammatory bowel disease: Okai et al. (2016) reported that high-affinity IgA was involved in gut microbiota regulation and murine colitis prevention (Okai et al., 2016). IgG galactosylation, which is associated with IgG functions, presents a lower level in IBD patients than in healthy individuals (Simurina et al., 2018). Besides, increased antibody-secreting plasma cells and a change in the proportion of immunoglobulin can be observed in IBD patients (Uzzan et al., 2016; Pararasa et al., 2019). However, patients with IgA deficiency only present with asymptomatic or slightly symptomatic (Fadlallah et al., 2018).