Dataset Information

CD200-CD200R1 signaling pathway regulates neuroinflammation after stroke.

ABSTRACT:

Objective

To study how the CD200-CD200R1 signaling pathway modulates poststroke inflammation and advances our knowledge of immune responses to ischemia insults in stroke.

Methods

Focal middle cerebral artery occlusion (MCAO) was induced in mice for 90 min, and mice were sacrificed at 1, 3, and 7 days of reperfusion. CD200, CD200R1, iNOS, and Arg-1 expression in ischemic brains was assessed by Western blotting (WB), and immunohistochemical (IHC) staining was performed to examine the expression of CD200 on neurons and CD200R1 on infiltrating lymphocytes. The severity of neurobehavioral deficits was evaluated by neurological deficit scores (NDS) and infarction volume estimated by TTC staining. To study the relationship between CD200/CD200R1 expression and the diversity of the neuroinflammatory response in stroke, CD200Fc (CD200R1 agonist) was subcutaneously injected at onset, at 1 day and 2 days after MCAO operation, and the brains were collected for detection at 3 days after MCAO/R (reperfusion).

Results

CD200 expression on neurons increased at 1 day and then decreased at 3 days after MCAO/R, and the expression of CD200R1 on lymphocytes showed an opposite temporal pattern as tested by IHC. The WB results showed that CD200/CD200R1 variance exhibited a similar pattern of IHC results, and the level of iNOS peaked at 1 day and then decreased gradually, but Arg-1 increased with time after MCAO/R in ischemic brains. After CD200Fc injection, CD200R1 expression significantly increased, and CD200Fc promoted Arg-1 but inhibited iNOS expression. The infarct volume and NDS of the group treated with CD200Fc were significantly smaller than those of the IgG2a-treated group.

Conclusions

The CD200-CD200R1 signaling pathway regulates neuroinflammation after stroke. Stimulation of CD200R1 by CD200Fc promotes the anti-inflammatory response and alleviates ischemic injury.

SUBMITTER: Zhao SC

PROVIDER: S-EPMC7749562 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Publications

CD200-CD200R1 signaling pathway regulates neuroinflammation after stroke.

Zhao Shou-Cai SC Heng Xu X Ya-Ping Wang W Di Luan L Wen-Qian Wu W Ling-Song Ma M Chu Zhao-Hu ZH Xu Yang Y

Brain and behavior 20201017 12

<h4>Objective</h4>To study how the CD200-CD200R1 signaling pathway modulates poststroke inflammation and advances our knowledge of immune responses to ischemia insults in stroke.<h4>Methods</h4>Focal middle cerebral artery occlusion (MCAO) was induced in mice for 90 min, and mice were sacrificed at 1, 3, and 7 days of reperfusion. CD200, CD200R1, iNOS, and Arg-1 expression in ischemic brains was assessed by Western blotting (WB), and immunohistochemical (IHC) staining was performed to examine th ...[more]

PMID: 33067924

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Dataset Information

CD200-CD200R1 signaling pathway regulates neuroinflammation after stroke.

Objective

Methods

Results

Conclusions

Publications

CD200-CD200R1 signaling pathway regulates neuroinflammation after stroke.

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