The migration of lymphocytes into inflammatory tissue requires the migrating cell to overcome mechanical forces produced by blood flow. A generally accepted hypothesis is that these forces are overcome by a multistep sequence of adhesive interactions between lymphocytes and endothelial cells. This hypothesis has been recently challenged by results demonstrating wall shear stress on the order of 20 dyn/cm2 in vivo and infrequent lymphocyteendothelial adhesion at wall shear stress >1-2 dyn/cm2 in vitro. Here, we show that lymphocyte slowing and transmigration in the skin is associated with microangiectasias, i.e., focal structural dilatations of microvessel segments. Microangiectasias are inducible within 4 days of the onset of inflammation and lead to a greater than 10-fold local reduction in wall shear stress. These findings support the hypothesis that a preparatory step to lymphocyte transmigration involves structural adaptations in the inflammatory microcirculation.
|Original language||English (US)|
|Number of pages||4|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|State||Published - Jun 10 2003|
- Cell movement
ASJC Scopus subject areas