Characteristics of the peripheral T cell immune response of patients at different stages of vascular cognitive impairment

Aim: To investigate the characteristics of the peripheral T cell immune response of patients at different stages of vascular cognitive impairment (VCI). Methods: 61 Arterial atherosclerotic cerebral infarct induced VCI patients, including 28 vascular dementia (VaD) cases, 33 no dementia (VCI-ND) cases, and 25 atherosclerotic cerebral infarct patients with normal cognitive function (CI-NC) as controls were enrolled. Peripheral CD8(+)T, CD4(+)CD25(+) Treg, CD4(+)L-17(+) Th17 cells proportion, and IL-1 beta, IL-2, IL-6, IFN-gamma levels, and neuropsychological function were assessed. Results: There was no difference in average age, gender ratio, years of education, and risk factors of infarct among the three groups. Peripheral CD4(+)CD25(+)Treg in VCI-ND and VaD groups were significantly lower than that in controls, and CD8(+) T cells were markedly elevated in VaD group. The IL-17(+) Th17 cell proportion did not differ significantly among three groups. IL-6 and IFN-gamma expression levels in VaD group were higher than those in other two groups. The VDAS-Cog executive function subscale score was negatively correlated with CD4(+)CD25(+) Treg proportion in VCI patients, and positively correlated with IL-6 levels. Conclusion: VCI patients demonstrated a decrease in peripheral CD4(+) Treg proportion and increased IL-6 expression, and both parameters were correlated with the decline of executive functions. (C) 2015 Elsevier B.V. All rights reserved.