Complement-mediated muscle cell lysis: a possible mechanism of myonecrosis in anti-SRP associated necrotizing myopathy (ASANM)

J Neuroimmunol. 2013 Nov 15;264(1-2):65-70. doi: 10.1016/j.jneuroim.2013.08.008. Epub 2013 Aug 30.

Abstract

The mechanism of necrotizing myopathy associated with antibodies to signal recognition particle (SRP) remains unclear. We investigated the effect of anti-SRP+serum and complement on cell viability in myoblast cultures. Cell viability was only slightly reduced by incubation with anti-SRP+serum compared with control serum. However, the addition of fresh complement resulted in a marked reduction in cell survival. Surface immunostaining for SRP, C3c and C5b-9 was demonstrated in cultures pre-incubated with anti-SRP+serum and complement, and in muscle biopsies from patients with myopathy. These findings provide further support for a complement-dependent antibody-mediated mechanism in anti-SRP associated myopathy.

Keywords: Anti-SRP antibody; Complement mediated cell lysis; Necrotizing myopathy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Antibodies / blood*
  • Cell Survival
  • Cells, Cultured
  • Complement C3c / metabolism*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Muscle Cells / metabolism
  • Muscle Cells / pathology
  • Muscle, Skeletal / pathology
  • Muscular Diseases* / immunology
  • Muscular Diseases* / metabolism
  • Muscular Diseases* / pathology
  • Myoblasts / metabolism
  • Myoblasts / pathology
  • Signal Recognition Particle / immunology*

Substances

  • Antibodies
  • Signal Recognition Particle
  • Complement C3c