Immune mechanisms have been invoked to explain coeliac disease and associations between this and other immunologically mediated diseases have been described. A direct relationship proposed is that coeliac disease may be associated with a range of autoimmune disease through the formation of immune complexes in the small intestine. It's more probable a common origin in an inherited predisposition to hypersensitive immuno responses to extrinsic antigens or auto-antigens. The association between coeliac disease and particular histocompatibility antigens was recognised.