Expression of interferon-stimulated genes in patients with rheumatoid arthritis on anti-B-cell therapy (preliminary results)

Objective : to evaluate the expression of interferon-stimulated genes (ISG) – interferon (IFN) signature – in patients with rheumatoid arthritis (RA) and its dynamics during anti-B-cell therapy. Patients and methods .We examined 20 patients with RA who received two infusions of the biosimilar rituximab (RTM) Acellbia® in a total dose of 1200 mg. Five genes were selected to evaluate IFN signature: IFI44L, MX1, IFIT1, RSAD2, EPSTI1. The expression of IFI44L and IFIT1 could not be determined for technical reasons, and further analysis included three genes – MX1, EPSTI1, RSAD2. IFN signature was calculated as the average value of the expression of three selected genes (IFN-score). Results and discussion . The initial expression level of MX1 was 11.48 (5.45–19.38), EPSTI1 – 12.83 (5.62–19.64), RSAD2 – 5.16 (2.73–10.4) and IFN-score –10.3 (5.18–17.12), in patients with RA it was statistically significantly higher than in healthy donors: 1.26 (0.73–1.6); 1.06 (0.81–1.48); 0.93 (0.72–1.19) and 1.09 (0.92–1.42), respectively (p<0.05). The IFN-score was high in 15 (75%) patients, low in 5 (15%). The use of RTM was accompanied by a statistically significant decrease in disease activity and the level of acute phase parameters (ESR, CRP) after 12 and 24 weeks of therapy (p<0.05). In the group as a whole, as well as in patients with a moderate effect of therapy or its absence, by the 24th week of treatment, an increase in the expression of RSAD2 (p<0.05) and a tendency to an increase in the IFN-score level (p=0.06) were observed. Conclusion . In patients with RA, an increased expression of ISH was found compared to healthy donors. An increase in the expression of RSAD2 and IFN-score is observed both in patients with a satisfactory effect of RTM and with no effect. The obtained results can be important for predicting the course of the disease and personalizing therapy.