title: Development of ELISA for the specific determination of autoantibodies against envoplakin and periplakin in paraneoplastic pemphigus.
abstract: BACKGROUND
  In paraneoplastic pemphigus (PNP), indirect immunofluorescence microscopy using rat bladder sections is widely used to search for circulating autoantibodies which are predominantly directed against envoplakin and periplakin. A sensitive and specific detection system for envoplakin/periplakin-specific autoantibodies is not yet available.
  
  
  METHODS
  Overlapping fragments spanning envoplakin and periplakin, respectively, were analyzed for their ability to bind PNP-specific autoantibodies by immunoblotting and ELISA in sera from patients with PNP (n=31), pemphigus vulgaris (n=30), and bullous pemphigoid (n=50) as well as healthy volunteers (n=140). The results were compared with those obtained by immunoblotting of extract of cultured human keratinocytes.
  
  
  RESULTS
  Immunoblot analysis revealed that most sera contained antibodies against the N-termini of both plakins as well as against the C-terminus of envoplakin. By ELISA, reactivities against envoplakin(1-481), envoplakin(1626-2033), and periplakin(1-324) were found in 25 (80.6%), 25 (80.6%), and 23 (74.2%) PNP sera, and in 1 (1.2%), 3 (3.7%), and 2 (2.5%) control sera, respectively.
  
  
  CONCLUSIONS
  The new ELISA based on an N-terminal fragment of envoplakin shows a high diagnostic accuracy to detect circulating autoantibodies in PNP. It is easy to be setup and standardized and can help to differentiate PNP patients from those with pemphigus vulgaris.
authors.affiliation: Department of Immunobiochemical Research, Institute for Experimental Immunology affiliated to EUROIMMUN AG, Lübeck, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Probst
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schlumberger
authors.forename: Winfried
authors.initials: W
authors.lastname: Stöcker
authors.forename: Andreas
authors.initials: A
authors.lastname: Recke
authors.forename: Enno
authors.initials: E
authors.lastname: Schmidt
authors.forename: Takashi
authors.initials: T
authors.lastname: Hashimoto
authors.forename: Xue Jun
authors.initials: XJ
authors.lastname: Zhu
authors.forename: Detlef
authors.initials: D
authors.lastname: Zillikens
authors.forename: Lars
authors.initials: L
authors.lastname: Komorowski
mesh_terms: D001323:Autoantibodies / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods* / Q000592:standards; D006801:Humans; D008565:Membrane Proteins / Q000276:immunology*; D010257:Paraneoplastic Syndromes / Q000175:diagnosis*; D010391:Pemphigoid, Bullous / Q000175:diagnosis; D010392:Pemphigus / Q000175:diagnosis*; D051179:Plakins / Q000276:immunology*; D011498:Protein Precursors / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D008565:Membrane Proteins; C491674:PPL protein, human; D051179:Plakins; D011498:Protein Precursors; C100754:envoplakin