CHARACTERIZATION OF A SV40-TRANSFORMED RHEUMATOID SYNOVIAL FIBROBLASTCELL-LINE WHICH RETAINS GENOTYPIC EXPRESSION PATTERNS - A MODEL FOR EVALUATION OF ANTIARTHRITIC AGENTS

A chimeric Adenovirus-Simian Virus 40 (AdSV40) containing the large T antigen was used to transform rheumatoid synovial fibroblasts. A rheum atoid synovial fibroblast cell line was established by infection of pr imary rheumatoid arthritis (RA) synovial fibroblasts at Passage 10 wit h AdSV40 recombinants followed by selection in semisoft agarose cultur es. The transformed cells grew anchor independent, exhibited continuou s proliferation (>65 passages) in monolayer culture, and formed multip le visible foci. The transformed synovial fibroblasts showed expressio n of the simian virus 40 large T antigen in the nucleus as determined by immunofluorescence staining. In addition, indirect immunofluorescen ce staining demonstrated that the transformed cells stained specifical ly with a fibroblast-specific antibody 1B10. Studies involving express ion of metalloproteinases showed that collagenase and stromelysin were induced by phorbol 12-myristate 13-acetate (PMA), and such an inducti on was repressed by dexamethasone typical of primary KA fibroblasts. L evels of mRNAs for IL-1 beta, TNF-alpha, and c-jun were increased by P MA, and the mRNA transcripts of these genes were also repressed by add ition of dexamethasone to the culture media. Our results indicate that transformed RA synovial fibroblasts display a similar gene expression pattern in response to PMA and dexamethasone as observed for untransf ormed primary RA synovial fibroblasts. These transformed rheumatoid ar thritis synovial fibroblast cells provide an ideal cell culture model in which to test the efficacy of novel arthritis gene therapy reagents .