Double-negative T cells remarkably promote neuroinflammation after ischemic stroke.
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ABSTRACT:
SUBMITTER: Meng H
PROVIDER: S-EPMC6431175 | biostudies-literature | 2019 Mar
REPOSITORIES: biostudies-literature
Publications
Double-negative T cells remarkably promote neuroinflammation after ischemic stroke.
Meng Hailan H Zhao Haoran H Cao Xiang X Hao Junwei J Zhang He H Liu Yi Y Zhu Min-Sheng MS Fan Lizhen L Weng Leihua L Qian Lai L Wang Xiaoying X Xu Yun Y
Proceedings of the National Academy of Sciences of the United States of America 20190228 12
CD3<sup>+</sup>CD4<sup>-</sup>CD8<sup>-</sup> T cells (double-negative T cells; DNTs) have diverse functions in peripheral immune-related diseases by regulating immunological and inflammatory homeostasis. However, the functions of DNTs in the central nervous system remain unknown. Here, we found that the levels of DNTs were dramatically increased in both the brain and peripheral blood of stroke patients and in a mouse model in a time-dependent manner. The infiltrating DNTs enhanced cerebral immu ...[more]
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Project description:ObjectiveTo determine the prevalence of diffusion-weighted imaging (DWI)-negative acute ischemic stroke (AIS) and to identify clinical characteristics of patients with DWI-negative AIS.MethodsWe systematically searched PubMed and Ovid/MEDLINE for relevant studies between 1992, the year that the DWI sequence entered clinical practice, and 2016. Studies were included based upon enrollment of consecutive patients presenting with a clinical diagnosis of AIS prior to imaging. Meta-analysis was performed to synthesize study-level data, estimate DWI-negative stroke prevalence, and estimate the odds ratios (ORs) for clinical characteristics associated with DWI-negative stroke.ResultsTwelve articles including 3,236 AIS patients were included. The meta-analytic synthesis yielded a pooled prevalence of DWI-negative AIS of 6.8%, 95% confidence interval (CI) 4.9-9.3. In the 5 studies that reported proportion data for DWI-negative and DWI-positive AIS based on the ischemic vascular territory (n = 1,023 AIS patients), DWI-negative stroke was strongly associated with posterior circulation ischemia, as determined by clinical diagnosis at hospital discharge or repeat imaging (OR 5.1, 95% CI 2.3-11.6, p < 0.001).ConclusionsA small but significant percentage of patients with AIS have a negative DWI scan. Patients with neurologic deficits consistent with posterior circulation ischemia have 5 times the odds of having a negative DWI scan compared to patients with anterior circulation ischemia. AIS remains a clinical diagnosis and urgent reperfusion therapy should be considered even when an initial DWI scan is negative.
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