THU0074 Effects of rituximab on the inflammatory and pro-thrombotic profiles of non-b cells of the immune and vascular systems of rheumatoid arthritis and systemic lupus erythematosus patients
Authors: I. Cecchi, C. Pérez-Sánchez, C. Pérez-Sánchez, L. Pérez-Sánchez, P. Ruiz-Limón, I. Arias de la Rosa, M.C. Ábalos-Aguilera, Y. Jiménez-Gómez, R. Ortega, E. Collantes, A. Escudero, M. Radin, N. Barbarroja, D. Roccatello, S. Sciascia, C. Lopez-Pedrera
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Treatment with B-cell depletion, including rituximab (RTX), has been proven successful in achieving remission from the active disease in Rheumatoid Arthritis (RA) and Systemic Lupus Erythematosus (SLE) patients. However, the effect of RTX on the Cardiovascular disease (CVD) associated to both autoimmune conditions has not been elucidated yet. The aim of this study was to investigate whether B-cell depletion therapy with RTX has an impact on activation of non-B cells of the immune and vascular systems in the context of CVD in RA and SLE patients <h3>Methods</h3> The analysis was carried out in plasma and purified leucocytes from 25 subjects, including 12 RA and 13 SLE patients. To evaluate the influence of B-cells depletion on the inflammatory profile of T-cells, purified lymphocytes from 6 RA and 7 SLE patients were treated with RTX (1 µg/ml) for 24 hours. B-cells depletion was assessed by flow cytometry and the changes occurred in the inflammatory profile of T cells were analysed by RT-PCR. The changes promoted in the activity of key intracellular regulators of pro-inflammatory cytokines were analysed by western blot in proteins purified from lymphocytes. In a second set of experiments, supernatants from cultured lymphocytes of 6 RA and 7 SLE patients was added –either, in the presence or in the absence of RTX- to cultured endothelial cells (HUVECs), monocytes, and neutrophils isolated from Healthy Donors (HDs) and incubated for 6 hour. The changes induced in the inflammatory/pro-thrombotic profile of these cells was analysed by RT-PCR. Finally, serum obtained from 6 RA and 6 SLE patients at baseline and after 3 months of therapy with RTX, was added to HUVECs, monocytes, and neutrophils isolated from HDs and the response was analysed by RT-PCR <h3>Results</h3> In parallel to the significant decline of B-cells, a downregulation of the pro-inflammatory profile of T-lymphocytes from RA and SLE patients was demonstrated, revealed by the significant drop of IL1, IL6, IL17, IFNγ, and TNFα gene expression levels. A decrease in the phosphorylation status and protein expression levels of STAT-3 and p38 was also found in T-cells treated with RTX. HUVECs, monocytes, and neutrophils incubated with the supernatant of RTX-treated lymphocytes from RA and SLE patients showed a decrease in the expression levels of various pro-thrombotic factors (i.e. TF, IL8, and VEGF) and cell-adhesion molecules (i.e. V-CAM, I-CAM and e-Selectin). Likewise, HUVECs, monocytes, and neutrophils treated with serum of RA and SLE patients after 3 months of therapy with RTX, showed a reduced expression of genes related to their pro-thrombotic and pro-inflammatory profiles <h3>Conclusions</h3> Depletion of B-cells induced by RTX might promote a beneficial effect in the CV risk-profile of RA and SLE patients through the modulation of the inflammatory and pro-thrombotic shapes of leukocytes and vascular endothelial cells <h3>Acknowledgements</h3> Funded by Junta de Andalucia (CTS-7940) and the Ministry of Health (ISCIII, PI15/01333 and RIER RD16/0012/0015) cofinanced with FEDER funds <h3>Disclosure of Interest</h3> None declared