Detection of Dnaj (Heat Shock Protein) and Other Mycobacterial related Antigens in Rheumatoid Arthritis using ELISA

There is strong evidence of an immune response to antigens found in mycobacteria in rheumatoid arthritis (RA) patients. We report here the presence of antigens strongly associated with mycobacteria in serum immune complexes of RA patients. A significant level of mycobacterial antigen was detected in RA patients' serum immune complexes and also in synovial fluids by both polyclonal anti-M. tuberculosis and monoclonal anti-DnaJ antibodies. We have found high levels of mycobacterial antigens using polyclonal antibodies in early stages of RA which however is reduced in late stages of the disease. While reverse situation was noted for DnaJ related antigen, using anti-DnaJ m-Ab, where low levels were detected in early RA they were comparatively high in late RA cases. Possibly in early infection, mycobacteria are involved and subsequently immune system restricts the multiplication of mycobacteria. However, during infection both host and pathogen undergo stress/heat shock resulting in heat shock protein production. The immune response to DnaJ or related antigens of pathogen and other bacteria may cross-react with homologous regions of host protein, and may induce an autoimmune disease.