Antibody to signal recognition particle in polymyositis

Arthritis Rheum. 1990 Sep;33(9):1361-70. doi: 10.1002/art.1780330908.


Using immunoprecipitation, we identified 13 patients with antibodies to the signal recognition particle (SRP) from a collection of sera representing 265 polymyositis/dermatomyositis (PM/DM) patients. Antibody reactivity with SRP was confirmed by enzyme-linked immunosorbent assay and immunoprecipitation with isolated dog pancreas SRP. The antibody was present in the serum of 4% of PM/DM patients, and 18% of PM/DM patients with anticytoplasmic antibodies other than anti-Jo-1, but not in patients with other conditions who had anticytoplasmic antibodies. Anti-SRP was associated with classic adult PM, and some of these cases were unusually severe and/or of rapid onset; it was not found in patients with overlap syndromes or with DM involvement. Unlike patients with antibodies to aminoacyl-transfer RNA synthetases, patients with anti-SRP had a low frequency of pulmonary fibrosis, as well as of arthritis and Raynaud's phenomenon. Anti-SRP antibodies may serve as a marker for a second, distinct subgroup of adult PM.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Antibodies / analysis*
  • Dermatomyositis / blood
  • Dermatomyositis / immunology
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Humans
  • Male
  • Middle Aged
  • Myositis / blood
  • Myositis / immunology*
  • Protein Sorting Signals / immunology*


  • Antibodies
  • Protein Sorting Signals