title: Linear IgA dermatosis with IgA and IgG autoantibodies to the 180 kDa bullous pemphigoid antigen (BP180): evidence for a distinct subtype.
abstract: BACKGROUND
  Autoantibodies in linear immunoglobulin A (IgA) disease (LAD) are reported to be of IgA class and directed against a 97-120 kDa epidermal antigen.
  
  
  METHODS
  We report a 39-year-old woman with clinical features of LAD and with circulating IgA and IgG autoantibodies to the 180 kDa bullous pemphigoid antigen (BP180).
  
  
  RESULTS
  Histopathology of lesional skin revealed a subepidermal blister with mixed inflammatory cell infiltrate. Direct immunofluorescence of perilesional skin showed linear deposits of IgA along the dermal-epidermal junction. The antigen specificity of the patient's circulating antibodies was determined by Western blotting and enzyme-linked immunoabsorbent assay (ELISA) using various antigen sources, including cultured human keratinocytes, dermal protein lysates, and purified laminin-5, as well as proteins corresponding to BP180, the 230 kDa bullous pemphigoid antigen (BP230), laminin-5 subunits, and collagen IV alpha1-alpha6 chains. IgA and IgG antibodies in the patient's serum were directed against BP180, and no IgA or IgG reactivity was found against the other skin antigens.
  
  
  CONCLUSIONS
  These data provide evidence for the presence of a subtype of LAD with dual IgA and IgG autoimmune response to BP180.
authors.affiliation: Department of Dermatology, Baylor College of Medicine, One Baylor Plaza FB800, Houston, TX 77030, USA.
authors.forename: Brandie J
authors.initials: BJ
authors.lastname: Metz
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Ruggeri
authors.forename: Sylvia
authors.initials: S
authors.lastname: Hsu
authors.forename: Jon A
authors.initials: JA
authors.lastname: Reed
authors.forename: Ali S
authors.initials: AS
authors.lastname: Ghohestani
authors.forename: Jouni
authors.initials: J
authors.lastname: Uitto
authors.forename: Reza F
authors.initials: RF
authors.lastname: Ghohestani
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000097:blood*; D001324:Autoantigens / Q000276:immunology*; D001327:Autoimmune Diseases / Q000175:diagnosis* / Q000276:immunology; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D003937:Diagnosis, Differential; D000071821:Dystonin; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D009419:Nerve Tissue Proteins; D024041:Non-Fibrillar Collagens; D010391:Pemphigoid, Bullous / Q000276:immunology*; D000097805:Collagen Type XVII
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D000071821:Dystonin; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D009419:Nerve Tissue Proteins; D024041:Non-Fibrillar Collagens; D000097805:Collagen Type XVII; C486268:DST protein, human