IgA and the IgA Fc receptor

IgA has traditionally been regarded a non-inflammatory antibody. This might indeed be true for secretory IgA (SIgA), which exerts its function at muco sal surfaces where commensal microorganisms and dietary antigens prevail. S erum IgA, however, potently triggers (pro)-inflammatory activity upon bindi ng to the myeloid IgA receptor. Fc alpha RI. Here, new insights in the role s of IgA and Fc alpha RI are addressed and a model integrating the various functions of IgA in immunity is discussed.