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Extravasating Neutrophil-derived Microparticles Preserve Vascular Barrier Function in Inflamed Tissue.

ABSTRACT: Emerging evidence suggests that gap formation and opening of the endothelial junctions during leukocyte extravasation is actively controlled to maintain the integrity of the vascular barrier. While the role for endothelial cells to this process has been well defined, it is not clear whether leukocytes are also actively contributing to endothelial barrier function. We have recently showed that extravasating leukocytes deposit microparticles on the subendothelium during the late stages of extravasation, which is LFA-1 dependent. Using multiphotonintravital microscopy (MP-IVM) of mouse cremaster muscle vessels in the current work, we show that microparticle formation and deposition maintains the integrity of the microvascular barrier during leukocyte extravasation. Inhibition of neutrophil-derived microparticle formation resulted in dramatically increased vascular leakage. These findings suggest that deposition of microparticles during neutrophil extravasation is essential for maintaining endothelial barrier function and may result in temporal difference between neutrophil extravasation and an increase in vascular leakage.

SUBMITTER: Lim K

PROVIDER: S-EPMC3718920 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Extravasating Neutrophil-derived Microparticles Preserve Vascular Barrier Function in Inflamed Tissue.

Lim Kihong K Sumagin Ronen R Hyun Young-Min YM

Immune network 20130630 3

Emerging evidence suggests that gap formation and opening of the endothelial junctions during leukocyte extravasation is actively controlled to maintain the integrity of the vascular barrier. While the role for endothelial cells to this process has been well defined, it is not clear whether leukocytes are also actively contributing to endothelial barrier function. We have recently showed that extravasating leukocytes deposit microparticles on the subendothelium during the late stages of extravas ...[more]

PMID: 23885224

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Dataset Information

Extravasating Neutrophil-derived Microparticles Preserve Vascular Barrier Function in Inflamed Tissue.

Publications

Extravasating Neutrophil-derived Microparticles Preserve Vascular Barrier Function in Inflamed Tissue.

Similar Datasets

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