Longterm culture of telomerase-transduced rheumatoid arthritis, fibroblast-like synoviocytes display a distinct gene expression pattern

Objective. To extend the lifespan of rheumatoid arthritis fibroblast-like synoviocytes (RA FLS) using human telomerase catalytic subunit (hTERT) and to test the hypothesis that longterm culture of hTERTRA FLS may display a disease-specific gene expression pattern. Methods. RA 516 FLS were transduced by hTERT and the replicative properties of hTERT-RA 516 FLS were evaluated by repeated expansion. Gene expressions in hTERT-RA 516 FLS (passage 8) were compared with the gene expressions in hTERT-osteoarthritis (OA) 13A FLS (passage 8) by microarrays and RT-PCR. After continuous expansion in culture for an additional 4 months, gene expression was examined again using real-time RT-PCR and microarray. Results. While primary RA 516 FLS stopped dividing after repeated culture for about 120 days, hTERTRA 516 FLS continued to grow at a steady rate. The hTERT-RA 156 FLS displayed a distinct gene expression pattern. different from hTERT-OA 13A FLS. Several putative. autoantigens and cytokine A2/monocyte chemoattractant protein-1 were expressed at significantly higher levels in longterm culture of hTERT-RA 516 FLS. Conclusion. Telomerase-transduced RA FLS offer an alternative cell model for the study of RA and for examination of cellular/genetic alterations in RA FLS. Our findings provide further support for the notion that RA FLS are altered cells.