title: Increased serum levels of a proliferation-inducing ligand in patients with bullous pemphigoid.
abstract: BACKGROUND
  B cells have been demonstrated to have critical roles in developing autoimmune bullous diseases. Recently identified tumor necrosis factor-like molecules, B cell-activating factor of the TNF family (BAFF) and a proliferation-inducing ligand (APRIL) are essential molecules for B cell development, survival, and proliferation. Although the functions of APRIL have not been fully evaluated, recent studies suggest that circulating levels of APRIL are increased in various autoimmune diseases, including systemic lupus erythematosus and rheumatoid arthritis.
  
  
  OBJECTIVE
  To determine serum APRIL levels in patients with pemphigus vulgaris (PV) and bullous pemphigoid (BP), and compare those with clinical findings and laboratory findings.
  
  
  METHODS
  Sera from 15 PV patients, 43 BP patients, and 15 normal controls were subjected to ELISA assays to measure serum APRIL, BAFF, Dsg3, and BP180 levels.
  
  
  CONCLUSIONS
  Circulating APRIL levels were significantly elevated in BP patients but not in PV patients, and correlated with serum BAFF levels. Our study revealed that serum APRIL levels tended to be increased in the quite early stage of disease. In conclusion, circulating APRIL levels may be a useful marker for early activation of autoimmune diathesis, and furthermore, an effective therapeutic target molecule in patients with BP.
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8655, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Watanabe
authors.forename: M
authors.initials: M
authors.lastname: Fujimoto
authors.forename: N
authors.initials: N
authors.lastname: Yazawa
authors.forename: H
authors.initials: H
authors.lastname: Nakashima
authors.forename: N
authors.initials: N
authors.lastname: Asashima
authors.forename: Y
authors.initials: Y
authors.lastname: Kuwano
authors.forename: Y
authors.initials: Y
authors.lastname: Tada
authors.forename: N
authors.initials: N
authors.lastname: Maruyama
authors.forename: H
authors.initials: H
authors.lastname: Okochi
authors.forename: K
authors.initials: K
authors.lastname: Tamaki
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D053264:B-Cell Activating Factor / Q000097:blood*; D015415:Biomarkers / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010391:Pemphigoid, Bullous / Q000097:blood* / Q000276:immunology*; D010392:Pemphigus / Q000097:blood / Q000276:immunology; D053300:Tumor Necrosis Factor Ligand Superfamily Member 13 / Q000097:blood*
chemical_list: D053264:B-Cell Activating Factor; D015415:Biomarkers; C505719:TNFSF13B protein, human; D053300:Tumor Necrosis Factor Ligand Superfamily Member 13