The roles of integrins in function of human neutrophils after their migration through endothelium into interstitial matrix.

We investigated the changes in neutrophil phenotype and function after transendothelial migration, and the roles played by integrin receptors in their behaviour. Neutrophils were tracked microscopically as they migrated through endothelial cells into collagen gels, and were retrieved at desired times. When endothelial cells were treated with increasing doses of tumour necrosis factor-α, neutrophils not only migrated in greater number, but also to a greater depth in the gel.

Delay of migrating leukocytes by the basement membrane deposited by endothelial cells in long-term culture.

We investigated the migration of human leukocytes through endothelial cells (EC), and particularly their underlying basement membrane (BM). EC were cultured for 20days on 3μm-pore filters or collagen gels to form a distinct BM, and then treated with tumour necrosis factor-α, interleukin-1β or interferon-γ. Neutrophil migration through the cytokine-treated EC and BM was delayed for 20-day compared to 4-day cultures.

Responses of endothelial cells from different vessels to inflammatory cytokines and shear stress: evidence for the pliability of endothelial phenotype.

Background/aims: Local haemodynamic and stromal microenvironments may determine the phenotype of endothelial cells (EC) and regulate their inflammatory responses.

Methods: We compared neutrophil recruitment by EC from human umbilical veins (HUVEC) or arteries (HUAEC) or from human coronary arteries (HCAEC) after 'static' culture or exposure to shear stress (2 Pa for 24 h) and treatment with tumour necrosis factor-alpha (TNF-alpha) or interleukin-1beta (IL-1beta).

Results: Static cultures of each type of EC recruited flowing neutrophils efficiently after treatment with TNF-alpha or IL-1beta; differences in culture media caused minor variations.