The Activity of JAK/STAT and NF-κB in Patients with Rheumatoid Arthritis

BACKGROUND: Research is still being conducted in order to determine the mechanisms responsible for the initiation of rheumatoid arthritis (RA) as well as for its persistence and progression. OBJECTIVES: The aim of this work was to establish the expression of the signal transducer and activator of transcription (STAT) transcription factors and the nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) transcription factor in peripheral blood leukocytes and synovial fluid cells. The correlations between the activation level of the transcription factors and the activity of the disease were also analyzed. MATERIAL AND METHODS: In total, the study included 34 RA patients and 19 healthy individuals as controls. The expression of NFκB, STAT1, STAT3, STAT4, STAT5 and STAT6 in peripheral blood leukocytes and synovial fluid cells was established. The immunocytochemistry method was used to determine the degree of activation of STAT and NF-κB transcription factors. For the location of the factors, primary polyclonal anti-STATs and monoclonal anti-NF-κB antibodies were used. RESULTS: The expression of STAT1, STAT3, STAT4, STAT5, STAT6 and NFκB was significantly higher in the group of RA patients than in the controls. No statistically significant differences were found between the expression of STATs in peripheral blood leukocytes and synovial fluid cells. CONCLUSIONS: In comparison with the control group, the expression of the STAT and NFκB transcription factors in RA patients was higher, which may be helpful in better understanding the etiopathogenesis of the disease in the future, and may potentially have important therapeutic implications.