Pathways Responsible for Human Autoantibody and Therapeutic Intravenous IgG Activity in Humanized Mice

Cell Rep. 2015 Oct 20;13(3):610-620. doi: 10.1016/j.celrep.2015.09.013. Epub 2015 Oct 8.


Immunoglobulin G (IgG) antibodies are major drivers of autoimmune pathology, but they are also used in the form of intravenous IgG (IVIg) therapy to suppress autoantibody activity. To identify the pathways underlying human autoantibody and IVIg activity, we established a humanized mouse model of an autoantibody-dependent autoimmune disease responding to treatment with IVIg preparations. We show that the human IgG subclass strongly impacts autoantibody activity and that the Fc-receptor genotype of the human donor immune system further modulates autoantibody activity. Human mononuclear phagocytes were responsible for autoantibody activity, and IVIg therapy was able to suppress disease pathology in an Fc-fragment-dependent manner. While highly sialylated IgG glycovariants were essential for IVIg activity, it was independent of the Fc-receptor genotype and did not result in a general block of activating or the neonatal Fc-receptor. These findings may help in the development of strategies to block autoantibody and enhance therapeutic IVIg activity in humans.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Intravenous
  • Animals
  • Antibodies, Monoclonal, Humanized / administration & dosage
  • Antibodies, Monoclonal, Humanized / immunology*
  • Autoantibodies / administration & dosage
  • Autoantibodies / immunology*
  • Humans
  • Immunoglobulin Fc Fragments / administration & dosage
  • Immunoglobulin Fc Fragments / immunology
  • Immunoglobulin G / administration & dosage
  • Immunoglobulin G / immunology*
  • Mice
  • Mice, Inbred NOD
  • Mice, SCID


  • Antibodies, Monoclonal, Humanized
  • Autoantibodies
  • Immunoglobulin Fc Fragments
  • Immunoglobulin G