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Updated: Apr 19, 2026
Recognition of Epidermal Transglutaminase by IgA and Tissue Transglutaminase 2 Antibodies in a Rare Case of Rhesus Dermatitis
Published on: December 15, 2011
Epidermal polymeric immunoglobulin receptors: leads from intraepidermal neutrophilic IgA dermatosis-type IgA
Atsunari Tsuchisaka1, Norito Ishii, Takahiro Hamada
1Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Fukuoka, Japan.
Abstract:
In this study, we attempted to identify unknown autoantigen for intraepidermal neutrophilic IgA dermatosis-type IgA pemphigus by novel IgA-specific immunoprecipitation. Mass-spectrometry study identified polymeric immunoglobulin receptor (PIGR) as the candidate protein, and we confirmed that PIGR expressed in both epidermis and cultured keratinocytes. Eukaryotic recombinant protein of PIGR expressed in COS7 cells was reacted with both patient and normal sera, indicating that PIGR binds physiologically to IgA. To detect antigen-specific binding by IgA autoantibodies, we performed several experiments using deglycosylated PIGR and F(ab)2 fragments from patient sera. However, these analyses suggested that patient IgA bound physiologically, but not immunologically, to PIGR. Nevertheless, our study provided two important insights. Newly developed IgA-immunoprecipitation system should be a useful tool in the future study of identification of antigens for IgA autoantibodies. Detection of epidermal PIGR in this study confirmed previous results and indicated possible immunological role of PIGR in epidermis.
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