Endothelial cell-T lymphocyte interactions:: iP-10 stimulates rapid transendothelial migration of human effector but not central memory CD4+ T cells.: Requirements for shear stress and adhesion molecules

The chemokine interferon (IFN)-gamma-inducible protein of 10 kDa (IP-10; CXCL10) has been implicated in recruitment of T cells into rejecting allografts yet appears ineffective at stimulating human peripheral blood CD4(+) T cells to transmigrate across tumor necrosis factor (TNF)-treated human endothelial cell (EC) monolayers in vitro. The same cells rapidly (within 15 min) transmigrate across TNF-treated EC monolayers overlaid with stromal cell-derived factor-1 alpha (SDF-1 alpha) and subjected to shear stress. The effector memory subset within the CD4(+) T cell population, defined as CD45RO(+), CD62L(10) and CCR7(10), which constitutes less than 10% of total CD4(+) T cells, does respond to IP-10 but requires enrichment to be observed in this model. Central memory T cells do not respond to IP-10. Transendothelial migration of effector memory CD4+ T cells requires TNF-pretreatment of the EC monolayer and application of venular shear force during the assay. TNF treatment of ECs may be effectively replaced by transduction of vascular cell adhesion molecule-1 or intercellular adhesion molecule-1 but not E-selectin.