The distribution of IgA pemphigus antigen in human skin and the role of IgA anti-cell surface antibodies in the induction of intraepidermal acantholysis

Molecular Diagnosis in Autoimmune Skin Blistering Conditions

“…While desmogleins 1 and 3 may represent minor antigens [66-68], immunoelectron microscopy studies suggest that IgA autoantibodies in these patients recognize a not yet identified non-desmosomal transmembranous protein [69]. The pathogenic potential of the IgA autoantibodies have not yet been clearly demonstrated and, in the absence of animal models of the disease, the pathomechanisms of blister formation in IgA pemphigus are not fully understood [3, 70]. …”

A Unique Case of Intra-Epidermal Neutrophilic Dermatosis-Type IgA Pemphigus Presenting with Subcorneal Pustules

“…In skin explant cultures using whole-serum specimens, intra-epidermal acantholysis was induced in cases of IgA pemphigus [19]. In these cases, antibody became fixed to cell surface antigen 3 h prior to the onset of acantholysis, suggesting a potential role for the circulating antibody in the induction of acantholysis [19]. In pemphigus vulgaris, several mechanisms for acantholysis have been suggested, including activation of complement, protease and transmembrane signalling, that downregulate cell-cell adhesion [20].…”

“…In pemphigus vulgaris, several mechanisms for acantholysis have been suggested, including activation of complement, protease and transmembrane signalling, that downregulate cell-cell adhesion [20]. Neither the in vivo bound IgA cell surface antibody nor the circulating IgA cell surface antibody is complement fixing [19]. Further studies are needed that examine whether IgA purified from patients is required to demonstrate the pathological potential, as well as the relevance of their possible interaction with granulocytes [21].…”