title: Autoantibody production from a thymoma and a follicular dendritic cell sarcoma associated with paraneoplastic pemphigus.
abstract: BACKGROUND
  Paraneoplastic pemphigus (PNP) is an autoimmune mucocutaneous disease. We previously reported that B cells in a Castleman tumour associated with PNP produced autoantibodies. However, it is uncertain whether the production of autoantibodies from the associated tumour is a common mechanism in PNP.
  
  
  OBJECTIVE
  To investigate autoantibody production in a thymoma and a follicular dendritic cell sarcoma that were excised from two patients with PNP.
  
  
  METHODS
  Tumour cells were cultured, and their surface markers were identified. Indirect immunofluorescence, immunoblotting and enzyme-linked immunosorbent assay (ELISA) using culture media from the tumours were used to detect PNP autoantibodies.
  
  
  RESULTS
  B cells with markers (CD22+, surface membrane IgG+ and surface membrane IgM+) of mature B lymphocytes constituted a proportion of cultured tumour cells in both tumours. Western blot showed that the medium from both the thymoma and the follicular dendritic cell sarcoma cells recognized 190-kDa periplakin and 210-kDa envoplakin bands of human epithelial proteins as well as recombinant linker regions of periplakin, envoplakin, desmoplakin and bullous pemphigoid antigen 1. ELISA was positive for antidesmoglein 3 antibody.
  
  
  CONCLUSIONS
  The presence and localization in tumours of B-lymphocyte clones against proteins of the plakin family and desmoglein 3 in skin may not be confined to PNP with Castleman disease, but is possibly a common mechanism in PNP associated with various tumours.
authors.affiliation: Department of Dermatology, Peking University First Hospital, 8 Xishiku St, Beijing 100034, China.
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.forename: D F
authors.initials: DF
authors.lastname: Bu
authors.forename: T
authors.initials: T
authors.lastname: Li
authors.forename: R
authors.initials: R
authors.lastname: Zheng
authors.forename: B X
authors.initials: BX
authors.lastname: Zhang
authors.forename: X X
authors.initials: XX
authors.lastname: Chen
authors.forename: X J
authors.initials: XJ
authors.lastname: Zhu
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000032:analysis*; D001402:B-Lymphocytes / Q000276:immunology; D015415:Biomarkers / Q000032:analysis; D015153:Blotting, Western; D002352:Carrier Proteins / Q000276:immunology; D003598:Cytoskeletal Proteins / Q000276:immunology; D020566:Dendritic Cells, Follicular / Q000276:immunology; D051184:Desmoglein 3; D051182:Desmogleins; D051180:Desmoplakins; D000071821:Dystonin; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005455:Fluorescent Antibody Technique; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D016130:Immunophenotyping; D008565:Membrane Proteins / Q000276:immunology; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000276:immunology; D010257:Paraneoplastic Syndromes / Q000276:immunology* / Q000473:pathology; D010392:Pemphigus / Q000276:immunology; D051179:Plakins; D011498:Protein Precursors / Q000276:immunology; D012186:Retroperitoneal Neoplasms / Q000276:immunology* / Q000473:pathology; D012509:Sarcoma / Q000276:immunology* / Q000473:pathology; D013945:Thymoma / Q000276:immunology* / Q000473:pathology; D013953:Thymus Neoplasms / Q000276:immunology* / Q000473:pathology; D014407:Tumor Cells, Cultured
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; C495294:DSP protein, human; C486268:DST protein, human; D051184:Desmoglein 3; D051182:Desmogleins; D051180:Desmoplakins; D000071821:Dystonin; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D051179:Plakins; C110037:Ppl protein, mouse; D011498:Protein Precursors; C100754:envoplakin