Light chain editors of anti-DNA receptors in human B cells

J Exp Med. 2014 Feb 10;211(2):357-64. doi: 10.1084/jem.20122340. Epub 2014 Jan 27.

Abstract

Receptor editing is a mechanism of self-tolerance used in newly generated B cells. The expressed heavy (H) or light (L) chain of an autoreactive receptor is replaced by upstream V genes which eliminate or modify autoreactivity. Editing of anti-DNA receptors has been characterized in anti-DNA transgenic mouse models including 3H9, 3H9/56R, and their revertant 3H9GL. Certain L chains, termed editors, rescue anti-DNA B cells by neutralizing or modifying DNA binding of the H chain. This editing mechanism acts on the natural H chain repertoire; endogenous H chains with anti-DNA features are expressed primarily in combination with editor L chains. We ask whether a similar set of L chains exists in the human repertoire, and if so, do they edit H chains with anti-DNA signatures? We compared the protein sequences of mouse editors to all human L chains and found several human L chains similar to mouse editors. These L chains diminish or veto anti-DNA binding when expressed with anti-DNA H chains. The human H chains expressed with these L chains also have relatively high arginine (Arg) content in the H chain complementarity determining region (H3), suggesting that receptor editing plays a role in establishing tolerance to DNA in humans.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Amino Acid Sequence
  • Animals
  • Antibodies, Antinuclear / metabolism*
  • Antibody Affinity
  • Antibody Specificity
  • B-Lymphocytes / immunology*
  • Complementarity Determining Regions / genetics
  • Conserved Sequence
  • DNA / immunology
  • DNA / metabolism
  • Humans
  • Immunoglobulin Heavy Chains / genetics
  • Immunoglobulin Heavy Chains / metabolism
  • Immunoglobulin Light Chains / genetics
  • Immunoglobulin Light Chains / metabolism*
  • Mice
  • Mice, Transgenic
  • Middle Aged
  • Molecular Sequence Data
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / immunology*
  • Self Tolerance
  • Sequence Homology, Amino Acid
  • Young Adult

Substances

  • Antibodies, Antinuclear
  • Complementarity Determining Regions
  • DNA receptor
  • Immunoglobulin Heavy Chains
  • Immunoglobulin Light Chains
  • Receptors, Cell Surface
  • DNA