Generation of IgG autoantibodies can be seen targeting these IgA1 immunoglobulins, which leads to the immune complex formation and an inflammatory process; however, the role of the same immune complexes for extrarenal components of HSP is not well established.46, 47, 48, 49 For vasculitic/extrarenal components of HSP, a multi-hit model involving IgA1-AECA (anti-endothelial cell antibody) is accepted.50 Here, IGHA1 is linked to hereditary spastic paraplegia.