IVIg inhibits classical pathway activity and anti-GM1 IgM-mediated complement deposition in MMN

J Neuroimmunol. 2010 Dec 15;229(1-2):256-62. doi: 10.1016/j.jneuroim.2010.08.023.


The effects of intravenous immunoglobulins (IVIg) on anti-GM1 IgM titer and function, classical complement pathway activity, and antibody-complement interaction were investigated in 62 patients with multifocal motor neuropathy (MMN). In vitro, IVIg decreased complement deposition by anti-GM1 IgM antibodies. First IVIg treatment (2 g/kg) decreased C1q and C4 concentrations and classical pathway activity in serum. In sera from patients receiving IVIg maintenance therapy (0.4 g/kg) C4 concentrations and classical pathway activity were generally lower at higher IgG concentrations. The beneficial effects of IVIg in MMN may be explained by reduced antibody-mediated complement deposition in nerves amplified by a systemically attenuated classical pathway.

MeSH terms

  • Adult
  • Analysis of Variance
  • Case-Control Studies
  • Complement Pathway, Classical / drug effects*
  • Complement System Proteins / classification
  • Complement System Proteins / metabolism*
  • Enzyme-Linked Immunosorbent Assay / methods
  • Female
  • G(M1) Ganglioside / immunology*
  • Humans
  • Immunoglobulin M / blood*
  • Immunoglobulins, Intravenous / administration & dosage*
  • Immunoglobulins, Intravenous / pharmacology
  • Male
  • Middle Aged
  • Motor Neuron Disease / blood*
  • Motor Neuron Disease / drug therapy


  • Immunoglobulin M
  • Immunoglobulins, Intravenous
  • G(M1) Ganglioside
  • Complement System Proteins