Immunogenicity of superoxide radical modified-DNA: studies on induced antibodies and SLE anti-DNA autoantibodies

Life Sci. 2004 Oct 15;75(22):2633-42. doi: 10.1016/j.lfs.2004.04.034.

Abstract

Superoxide anion radical (SAR) is formed in almost all aerobic cells and it is the most abundant species generated by several enzymatic and non-enzymatic pathways in mammalian tissues, leading to unfavorable alteration of biomolecules including DNA. The SAR-modified macromolecules have been implicated in several disease states including disorders of inflammation. The SAR-induced damage to DNA showed hyperchromicity, single strand breaks, decrease in melting temperature, and modification of bases. Superoxide modified-DNA in rabbits elicited high titer antibodies and showed diverse antigens binding characteristics. The induced antibodies recognized native DNA and other nucleic acid polymers. Anti-DNA IgG from SLE sera, purified on Protein-A-Sepharose matrix, exhibited increased recognition of superoxide anion radical modified-DNA than native DNA in competitive immunoassay. The visual formation of immune complex between induced antibodies and native DNA, and between SLE anti-DNA IgG and superoxide modified-DNA, is a clear indication of property sharing between SLE autoantibodies and experimentally induced antibodies against superoxide modified-DNA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Antinuclear / immunology*
  • DNA / immunology*
  • DNA / metabolism
  • DNA Damage
  • Immunoglobulin G / immunology
  • Lupus Erythematosus, Systemic
  • Rabbits
  • Superoxides / metabolism*

Substances

  • Antibodies, Antinuclear
  • Immunoglobulin G
  • Superoxides
  • DNA