Mechanisms Of Iducible Costimulator-mediated Costimulation In The Immunopathology Of Behcet's Disease

Objective To investigate the express of inducible co-stimulator(ICOS)on peripheral blood T lymphocyte subsets in patients of Behcet's disease( BD ) and to find out the relationship with disease-activity, disease-stage so as to pave the way for future studying the possibly immunologically pathological role of ICOS in BD. The levels of INF-γand IL-4 secreted were tested on peripheral blood in patients of BD, and to find out the ratio of Th1/Th2 and Tc1/Tc2 on peripheral blood in patients of BD as so to study immune condition in patients of BD.Methods Peripheral blood samples were collected from 22 patients with BD, and 6 patients of disease-stage. Three-color flow cytometry was used to detect the levels of ICOS expression on peripheral blood T lymphocyte subsets, and INF-γand IL-4 secrete on peripheral blood in patients of BD. The results and relationship of disease were analyzed. Twenty-two healthy subjects were used as controls.Results The first, compared with the healthy subjects the percentage of CD4+ T cells was no significant on peripheral blood of BD(p>0.05), but CD8+ T cells was significantly decreased(p<0.05),the ratio of CD4+/CD8+ was significantly decreased(p<0.05), the percentages of CD4+CD28+ and CD8+CD28+ T cells were significantly decreased(all p<0.05). The second, compared with the healthy subjects the levels of ICOS expression CD4+ and CD8+T cells on peripheral blood T lymphocyte subsets in patients of BD during disease-activity were significantly increased(all p<0.05), but in patients of BD during disease-stage were no significant(all p>0.05); The levels of ICOS expression on peripheral blood CD4+CD28+ and CD4+CD28- and CD8+CD28- in patients of BD during disease-activity were significantly increased (all P<0.05 ) , but ICOS expression on peripheral blood CD4+CD28+ and CD4+CD28- and CD8+CD28+ and CD8+CD28- in patients of BD during disease-stage were significant(all P>0.05). The thirty, compared with healthy subjects the levels of INF-γsecreted were significantly increased on peripheral blood Th and Tc cells in patients of BD during disease-activity(P<0.05), but the levels of INF-γsecreted were no significant on peripheral blood Th and Tc cells in patients of BD during disease-stage (P>0.05), the levels of IL-4 secreted were significantly increased on peripheral blood Th and Tc cells in patients of BD during disease-activity(P<0.05), but the levels of IL-4 secreted were no significant on peripheral blood Th and Tc cells in patients of BD during disease-stage( P>0.05 ).Conclusion ICOS is aberrantly highly expressed on certain peripheral blood T lymphocyte subsets in patients with BD, there are significantly increased between the levels of INF-γand IL-4 secreted , which is related to disease-activity, thus ICOS may play a role in BD pathogenesis.