Autoantibodies detected to expressed K+ channels are implicated in neuromyotonia

Ann Neurol. 1997 Feb;41(2):238-46. doi: 10.1002/ana.410410215.

Abstract

Antibody-mediated autoimmunity underlies a diverse range of disorders, particularly in the nervous system where the extracellular domains of ion channels and receptors are especially vulnerable targets. We present here a novel means of detecting autoantibodies where the genes of the suspected target proteins are known, and use it to detect specific autoantibodies in acquired neuromyotonia (Isaacs' syndrome), a disorder characterized by hyperexcitable motor nerves and sometimes by central abnormalities. We expressed different human brain voltage-gated potassium channels in Xenopus oocytes by injecting the relevant alpha-subunit complementary RNA, and detected antibody binding by immunohistochemistry on frozen sections. Antibodies were detected to one or more human brain voltage-gated potassium channel in 12 of 12 neuromyotonia patients and none of 18 control subjects. The results establish neuromyotonia as a new antibody-mediated channelopathy and indicate the investigative potential of this molecular immunohistochemical assay.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Autoantibodies / analysis*
  • Fasciculation / metabolism*
  • Humans
  • Potassium Channels / metabolism*

Substances

  • Autoantibodies
  • Potassium Channels