P099 Patients with ulcerative colitis show increased Treg number in peripheral blood after 1 year of anti-TNF therapy
D. Kyurkchiev*1, E. Ivanova-Todorova1, Z. Spasova2, T. Velikova1, M. Petkova2, E. Krasimirova1, K. Tumangelova - Yuzeir1, L. Mateva - Vladimirova2
1Laboratory of Clinical immunology, University hospital St. Ivan Rilski, Medical university of Sofia, Sofia, Bulgaria, 2Clinic of gastroenterology, University hospital ‘St. Ivan Rilski’, Department of Internal medicine, Medical University of Sofia, Bulgaria, Sofia, Bulgaria
Tregs are cells with well-known immunosuppressive functions realised by contact-dependent mechanisms (expression of CTLA-4 and PD-L1) and cytokine secretion (TGFβ and IL-10). These cells are often found on the bowel mucosa, where they suppress excessive T-cell mediated immune reactions. The aim of our study was to investigate the dynamics of changes in peripheral blood of Treg population in patients with ulcerative colitis (UC) before and after anti-TNF therapy.
Eight patients on anti-TNF therapy and 15 healthy controls are enrolled in the study. Using flow cytometry the percentage of Tregs was detected before and after 1 year on anti-TNF therapy.
Our results demonstrate that before anti-TNF therapy the mean percentage of Tregs in UC patients is lower than in healthy persons. In six patients after 1 year of anti-TNF treatment the number of Tregs increased reaching that of the healthy persons. In the same patients the activity of the disease (Mayo score) strongly decrease. Two of the patients are non-responders. They did not show up-regulation of Tregs as well as clinical improvement.
Our results demonstrate that anti-TNFα therapy may lead to a significant rise in the number of peripheral blood Tregs in UC patients responding to this therapy.