Abstract 51: Peripheral Regulatory T cells and Th17 Cells Is Associated With Pathogenesis of Moyamoya Disease

Abstract

Background: Despite unclear pathogenesis, previous studies have suggested immune responses may play a pivotal role in the process of Moyamoya disease (MMD), a rare cerebrovascular occlusive disorder. The objective of this study is aimed to explore the change of peripheral Treg/Th17 in MMDpatients and whether the change is associated with pathogenesis of MMD. Methods: In the present study, we collected 26 MMD patients diagnosed by angiography according to the diagnostic criteria of definitive MMD and recruited 32 healthy volunteers. To explore the balance of peripheral Treg/Th17 in MMD patients, lymphocytes in peripheral blood were harvested and flow cytometry was used to measure the percentage of Treg and Th17in CD4+ Tcells, respectively. Meanwhile, relevant cytokines in serum were measured to evaluate the function of Treg and Th17 cells. Results: According to Suzuki’s angiographic staging of moyamoya disease, patients were divided into subgroups of the preliminary-term, medium-term and late-term. Cerebral hemorrhage is thefirstsymptom of onset occuringin half of patients, followed bycerebral ischemia.Our data revealed that both the percentage of Treg and Th17 cells in peripheral blood lymphocytes was increased in MMD patients compared with volunteer group. Meanwhile, the levels of IL-6, IL-10,IL-12, IL-17, TNF-α, VEGF and TGF-β in serum were significantly increased in MMD patients. In this study, the level of HMGB-1, a middle-late period inflammation biomarker, in serum of MMD patients is obviously elevated compared with volunteers. However, the ratio of Treg/Th17 had no significant difference in MMD patients compared to healthy volunteers. Intriguingly, our data revealed that ratio of Treg/Th17 was significantly increased in late-term MMD patients compared with medium-term patients as evidenced by elevated percentage of Treg cells.. In addition, TGF-β level in later-term MMD patients was significantly higher than this in medium-term MMD patients. No difference was observed in the way of onset and gender between two groups. Conclusion: Enhanced peripheral Treg and Th17 in MMD patients suggested that there may be an immunological component in the pathogenesis of MMD. Peripheral Treg may be associated with pathological process of MMD.