Hydroxyl radical damaged Immunoglobulin G in patients with rheumatoid arthritis: Biochemical and immunological studies

Abstract: Objectives: The role of hydroxyl radical (ed Immunoglobulin G (IgG) in rheumatoid arthritis (RA) has been investigated. Design and methods: The study was hypothesized that oxidative by-products, like IgG, help to initiate autoimmunity in RA. To test this hypothesis, IgG was modified by ogenicity of native and modified IgG was probed by inducing polyclonal antibodies in rabbits. Autoantibodies from 77 RA sera were screened by direct binding and competition ELISA. Results: The extensive damage to IgG. The s found to be highly immunogenic in rabbits as compare to native IgG. High degree of specific binding by 72.7% RA sera autoantibodies towards s observed, in comparison to its native analogue (p <0.05). Conclusion: The cation of IgG causes perturbations, resulting in the generation of neo-epitopes, and making it a potential immunogen. The IgG modified with the ·OH may be one of the factors for the induction of circulating RA autoantibodies. [Copyright &y& Elsevier]