Journal of
Clinical Immunology and Immunopathology Research

  • Abbreviation: J. Clin. Immunol. Immunopathol. Res.
  • Language: English
  • ISSN: 2141-2219
  • DOI: 10.5897/JCIIR
  • Start Year: 2009
  • Published Articles: 22

Full Length Research Paper

Autoantibodies against reactive oxygen species modified immunoglobulin G in patients with type 1 diabetes mellitus

Naila Rasheed
  • Naila Rasheed
  • Division of Pharmacology, Central Drug Research Institute, Lucknow, India.Department of Medical Biochemistry, College of Medicine, Qassim University, P.O. Box 6655, Buraidah-51452, KSA.
  • Google Scholar
Nadeem A. Ansari
  • Nadeem A. Ansari
  • Department of Biochemistry, Faculty of Medicine, J. N. Medical College, A.M.U., Aligarh, India.
  • Google Scholar
Lokendra Kumar
  • Lokendra Kumar
  • Department of Biochemistry, SBSPGI, Balawala, Dehradun, India.
  • Google Scholar
Trivendra Tripathi
  • Trivendra Tripathi
  • Department of Biochemistry, Faculty of Medicine, J. N. Medical College, A.M.U., Aligarh, India.
  • Google Scholar
Rizwan Ahmad
  • Rizwan Ahmad
  • Department of Biochemistry, SBSPGI, Balawala, Dehradun, India.
  • Google Scholar
afar Rasheed
  • afar Rasheed
  • Department of Biochemistry, SBSPGI, Balawala, Dehradun, India.Department of Medical Biochemistry, College of Medicine, Qassim University, P.O. Box 6655, Buraidah-51452, KSA.
  • Google Scholar


  • Article Number - B891A785441
  • Vol.3(1), pp. 10-19, January 2011
  •  Accepted: 16 July 2010
  •  Published: 31 January 2011

Abstract

The role of hydroxyl radicals (.OH) damaged immunoglobulin G (IgG) in insulin dependent diabetes mellitus has been investigated. IgG was isolated from normal human serum and modified by hydroxyl radicals, generated by UV irradiation of hydrogen peroxide. .OH-induced modification on IgG has been studied by ultra-violet (UV) absorption spectroscopy, tryptophan/tyrosine fluorescence, circular dichrosim, SDS-PAGE and carbonyl groups estimations. .OH caused extensive damage to IgG. The binding characteristics of circulating antibodies in type 1 diabetes patients against native and modified IgG were assessed. Type 1 diabetes patients (n = 36) were examined by direct binding ELISA and the results were compared with healthy age-matched controls (n = 22). High degree of specific binding of diabetes sera towards .OH modified IgG, in comparison to its native analogue (p < 0.05). Sera from normal human subjects showed negligible binding with either antigen. Our results conclude that .OH-modification of IgG causes structural perturbations, resulting in the generation of neo-epitopes and making it a potential immunogen. IgG modified with .OH may be one of the factors for the induction of circulating type 1 diabetes autoantibodies.

 

Key words: Autoantibodies, hydroxyl radicals, immunoglobulin G, .OH-IgG, type 1 diabetes mellitus.