Getting to the site of inflammation: the leukocyte adhesion cascade updated

Klaus Ley1, Carlo Laudanna, Myron I Cybulsky

  • 1Robert M. Berne Cardiovascular Research Center and Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA. klaus@liai.org

Neutrophil recruitment, lymphocyte recirculation and monocyte trafficking all require adhesion and transmigration through blood-vessel walls. The traditional three steps of rolling, activation and firm adhesion have recently been augmented and refined. Slow rolling, adhesion strengthening, intraluminal crawling and paracellular and transcellular migration are now recognized as separate, additional steps. In neutrophils, a second activation pathway has been discovered that does not require signalling through G-protein-coupled receptors and the signalling steps leading to integrin activation are beginning to emerge. This Review focuses on new aspects of one of the central paradigms of inflammation and immunity--the leukocyte adhesion cascade.

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