title: Novel autoantibodies against 7SL RNA in patients with polymyositis/dermatomyositis.
abstract: OBJECTIVE
  Autoantibodies against signal recognition particle (SRP) are detected in patients with polymyositis/dermatomyositis (PM/DM). The SRP consists of 7SL RNA and 6 protein components. We examined autoantibodies against deproteinized 7SL RNA in PM/DM patients with anti-SRP antibodies and evaluated the association of anti-7SL RNA antibodies with PM/DM clinically and serologically.
  
  
  METHODS
  Sera from 10 Japanese and 22 North American PM/DM patients with anti-SRP antibodies were tested for the presence of anti-7SL RNA antibodies, using the sera to immunoprecipitate deproteinized RNA extracts derived from HeLa cells.
  
  
  RESULTS
  The immunoprecipitation analysis indicated that 5 Japanese (50%) and one North American (5%) patient with anti-SRP antibodies had novel autoantibodies against deproteinized 7SL RNA. The frequency of anti-7SL RNA antibodies was significantly higher in Japanese than North American patients (p = 0.006). The presence of anti-7SL RNA antibodies appeared to be associated with DM (2 patients) and finger swelling (2 PM patients). The seasonal onset of the disease was different (p = 0.008) for Japanese PM/DM patients with anti-7SL RNA antibodies, who developed the disease between October and January (mean month November; p = 0.01) from that of patients without these antibodies, who developed it between June and August (mean month July; p = 0.01).
  
  
  CONCLUSIONS
  Novel autoantibodies against 7SL RNA were identified in patients with PM/DM, and the presence of these antibodies was correlated to ethnic background, clinical features, and season of disease onset. These findings indicated that autoantibodies against 7SL RNA are a novel serological marker for a subset of PM/DM cases.
authors.affiliation: Department of Laboratory Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Satoh
authors.forename: Tetsuroh
authors.initials: T
authors.lastname: Okano
authors.forename: Toshimichi
authors.initials: T
authors.lastname: Matsui
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Watabe
authors.forename: Takashi
authors.initials: T
authors.lastname: Ogasawara
authors.forename: Kouya
authors.initials: K
authors.lastname: Kubo
authors.forename: Masataka
authors.initials: M
authors.lastname: Kuwana
authors.forename: Noreen
authors.initials: N
authors.lastname: Fertig
authors.forename: Chester V
authors.initials: CV
authors.lastname: Oddis
authors.forename: Hirobumi
authors.initials: H
authors.lastname: Kondo
authors.forename: Tohru
authors.initials: T
authors.lastname: Akahoshi
mesh_terms: D000328:Adult; D044466:Asian People; D001323:Autoantibodies / Q000032:analysis / Q000276:immunology*; D015415:Biomarkers; D015331:Cohort Studies; D003882:Dermatomyositis / Q000097:blood / Q000208:ethnology / Q000276:immunology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D047468:Immunoprecipitation; D008297:Male; D008875:Middle Aged; D017285:Polymyositis / Q000097:blood / Q000208:ethnology* / Q000276:immunology*; D011336:Probability; D020733:RNA, Small Cytoplasmic / Q000032:analysis / Q000276:immunology*; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018271:Signal Recognition Particle / Q000032:analysis / Q000276:immunology*; D044465:White People
chemical_list: C115990:7SL RNA; D001323:Autoantibodies; D015415:Biomarkers; D020733:RNA, Small Cytoplasmic; D018271:Signal Recognition Particle