CONTENT AND PHENOTYPE OF BLOOD CCR6+ AND CCR9+ T-HELPER CELLS IN ADOLESCENTS WITH CROHN’S DISEASE
Crohn’s disease is a chronic recurrent inflammatory disease of the human intestine, which can be caused by the action of provoking factors against the background of different variants of genetic predisposition. The development of the disease is associated with a pathological response of effector T-cells to the antigens of the intestinal microflora. In this study, we examined the blood levels and phenotype of CD4+ lymphocytes with chemokine receptors involved in migration into intestine (CCR9 and CCR6) or lymphoid tissue (CCR7 and CXCR5) in adolescents with Crohn’s disease. A group of patients with Crohn’s disease and a comparison group were randomized by age and concomitant pathologies. It was shown that in Crohn’s disease the content of CD4+CD45RO+ T-helper cells in the blood increases 2 times, and the content of effector/memory T-cells with phenotype CD4+CD45RO+CСR7-CСR6+ increases 4.4-fold. CD4+CD45RO+CСR6+ cells, increasing their numbers in Crohn’s disease, did not express the molecule ICOS and the chemokine receptor CХСR5. We did not find an increase in the concentration of CD4+CСR9+ cells in the blood of patients with Crohn’s disease. Nonetheless, CСR9+CСR7+, CCR9+CXCR5+ and CCR9-CXCR5+ cells augmented their percentages in the structure of immature CD4+CD45RO- T-lymphocytes. CD4+CD45RO-CСR9+ cells showed an increased level of expression of the molecules ICOS, PD1 and CXCR5 in comparison with CD4+CD45RO-CСR9- cells.