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Distinct myeloid cell subsets promote meningeal remodeling and vascular repair after mild traumatic brain injury.

ABSTRACT: Mild traumatic brain injury (mTBI) can cause meningeal vascular injury and cell death that spreads into the brain parenchyma and triggers local inflammation and recruitment of peripheral immune cells. The factors that dictate meningeal recovery after mTBI are unknown at present. Here we demonstrated that most patients who had experienced mTBI resolved meningeal vascular damage within 2-3 weeks, although injury persisted for months in a subset of patients. To understand the recovery process, we studied a mouse model of mTBI and found extensive meningeal remodeling that was temporally reliant on infiltrating myeloid cells with divergent functions. Inflammatory myelomonocytic cells scavenged dead cells in the lesion core, whereas wound-healing macrophages proliferated along the lesion perimeter and promoted angiogenesis through the clearance of fibrin and production of the matrix metalloproteinase MMP-2. Notably, a secondary injury experienced during the acute inflammatory phase aborted this repair program and enhanced inflammation, but a secondary injury experienced during the wound-healing phase did not. Our findings demonstrate that meningeal vasculature can undergo regeneration after mTBI that is dependent on distinct myeloid cell subsets.

SUBMITTER: Russo MV

PROVIDER: S-EPMC6426637 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Distinct myeloid cell subsets promote meningeal remodeling and vascular repair after mild traumatic brain injury.

Russo Matthew V MV Latour Lawrence L LL McGavern Dorian B DB

Nature immunology 20180416 5

Mild traumatic brain injury (mTBI) can cause meningeal vascular injury and cell death that spreads into the brain parenchyma and triggers local inflammation and recruitment of peripheral immune cells. The factors that dictate meningeal recovery after mTBI are unknown at present. Here we demonstrated that most patients who had experienced mTBI resolved meningeal vascular damage within 2-3 weeks, although injury persisted for months in a subset of patients. To understand the recovery process, we s ...[more]

PMID: 29662169

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Distinct myeloid cell subsets promote meningeal remodeling and vascular repair after mild traumatic brain injury.

Publications

Distinct myeloid cell subsets promote meningeal remodeling and vascular repair after mild traumatic brain injury.

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