The role of ICAM-1 in leukocyte adherence to endothelial cells induced by hypoxia/reoxygenation

Objective: To determine whether intercellular adhesion molecule-1 (ICAM-1) mediats the polymorphonuclear leukocyte (PMN) adherence to endothelial cells elicited by hypoxia/reoxygenation (H/R).

Methods: Human umbilical vein endothelial cells (HUVEC) monolayers was exposed to hypoxia for 30 min or 120 min then reoxygenated. Count the number of PMN in adhesion assays. Expression of ICAM-1 and ICAM-1 mRNA was detected by immunohistochemical analysis and in situ hybridization.

Results: PMN adhesion to HUVEC exposed to H/R was significantly increased (1 fold) as compared with that of control (P < 0.01). H/R induced hyperadherence was significantly diminished by monoclonal antibodies directed at ICAM-1 or CD11a/CD18. The results showed an increased expression of ICAM-1 and ICAM-1 mRNA on HUVEC exposed to H/R. Hypoxic HUVEC might be responsible for PMN adesion.

Conclusions: ICAM-1 mediated the adhesive interaction between PMN and VEC induced by hypoxia/reoxygenation.