Figure 1.

Pathogenesis of IgG4-related disease.

To our current understanding, the pathogenesis of IgG4-related disease is a multifactorial process which is initiated by an immune response to pathogen proteins that mimic self-antigens or classical self-antigens that lead to an autoimmune response which is initially predominantly driven by a Th1-type response. This leads to inflammatory tissue infiltration which results in organ swelling. A sustained inflammatory process can induce a switch towards a Th2-type dominated response and activation of peripheral T-regs, followed by eosinophilia, IgE production, differentiation of IgG4 producing plasma cells, organ dysfunction, and tissue fibrosis.