Abstract
This study investigated the localization of proto-oncogenes and cytokine mRNAs in the synovium of rheumatoid arthritis.
Synovial tissues were obtined from patients with rheumatoid arthritis (RA), osteoarthritis (OA), and traumatic arthritis (TA) at the time of Surgery. The sections were processed for in hybridization histochemistry using oligoncleotide probes for IL-1, IL-6, TNF-α, c-fos and c-jun.
In the synovium of RA, IL-6mRNAs were expressed strolgly in the lining layer, sublining area and stromal area, while IL-1 mRNAs were detected in the stromal area where cells aggregated. TNF-α mRNAs were expressed in the stromal area, although weakly, Proto-oncogene, c-fos and c-jun mRNAs were expressed in the lining layer, and endoetheliocytes. Other synovial tissues from non-RA patients, the mRNAs were found weakly or were undtectaltable.
These results suggest that activated cells in the synovium synthesized cytokines which then stimulate the expression of proto-oncogene. These phenomena may play an important role in the joint destruction seen in RA.