Microarray analysis of the synovial membrane of rheumatoid arthritis patients undergoing anti-TNF therapy

Synovial biopsies of Rheumatoid Arthritis patients were obtained at week 20 of anti-TNF therapy. The clinical response to therapy was determined comparing the DAS28 at this time point with the baseline DAS28, using the EULAR response criteria. Gene expression profiles of patients responding to anti-TNF therapy were compared to non-responders and different genes, pathways and deconvoluted cell types were found to be differential between both groups of rheumatoid arthritis patients. Synovial samples were obtained by guided arthroscopy using a 2.7 mm arthroscope from 11 Rheumatoid Arthritis patients starting anti-TNF therapy. Samples were immediately preserved in RNALater at -80ºC until extraction. After total RNA extraction, gene expression profiles for 21,000 genes were obtained using WG6 Illumina Sentrix whole genome Beadchips .