CD79A and Henoch-Schoenlein purpura: Furthermore, the abnormal glycosylation of IgA is often the main characterization of severe autoimmune diseases (Singh et al., 2014), especially IgA nephropathy (IgAN) and IgA vasculitis (IgAV) (Suzuki et al., 2018; Suzuki and Novak, 2021).