Mice lacking E-selectin show normal numbers of rolling leukocytes but reduced leukocyte stable arrest on cytokine-activated microvascular endothelium.

Autor: Milstone DS; Department of Pathology, Brigham and Women's Hospital, Boston, MA, USA., Fukumura D, Padgett RC, O'Donnell PE, Davis VM, Benavidez OJ, Monsky WL, Melder RJ, Jain RK, Gimbrone MA Jr
Jazyk: angličtina
Zdroj: Microcirculation (New York, N.Y. : 1994) [Microcirculation] 1998; Vol. 5 (2-3), pp. 153-71.
Abstrakt: Objective: Previous work indicated that E-selectin mediates transient interactions between leukocytes and cytokine-activated endothelium in vitro. Here we examine the role of E-selectin in blood leukocyte interactions with microvascular endothelium in vivo.
Methods: E-selectin-deficient (E-/-) mice were produced by gene targeting. The effect of this null mutation on leukocyte-endothelial interactions was determined by intravital microscopy before and 4 to 5 hours after local administration of the proinflammatory cytokine tumor necrosis factor alpha (TNF alpha) in dermal microvessels with low blood flow (dorsal skin-fold chambers, intact ear skin), and after endotoxin activation in exteriorized mesenteric microvessels with higher blood flow.
Results: E-/- mice were viable, fertile with normal circulating leukocyte and platelet profiles. Approximately 60% of circulating leukocytes rolled in dermal microvessels of both normal (E+/+) and E-/- mice without inflammatory stimulation. After local administration of TNF alpha, rolling increased modestly and equivalently in both genotypes. The main effect of TNF alpha was a dramatic increase in leukocyte stable adhesion and, unlike rolling, this manifestation of endothelial activation was significantly reduced in E-/- animals. This reflected fewer dermal microvessels supporting higher adhesion densities in E-/- mice, and a similar trend was observed in mesenteric microvessels.
Conclusions: E-selectin plays a previously unappreciated role in facilitating and/or mediating stable adhesion of leukocytes to inflamed microvascular endothelium.
Databáze: MEDLINE
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