Perflubron attenuates neutrophil adhesion to activated endothelial cells in vitro

Infiltration of activated neutrophils into the lung appears to be a key ele ment in the severe lung injury that develops in animal models of acute lung injury. Partial liquid ventilation with perflubron has been shown to ameli orate tissue damage compared with conventional mechanical ventilation in ac ute lung injury models. Pilot experiments indicated that indirect exposure to perflubron could modulate the degree to which subsequent neutrophil bind ing to endothelial cell monolayers was upregulated after lipopolysaccharide activation. Endothelial cell monolayers preexposed to perflubron showed >4 0% reductions in the surface steady-state levels of E-selectin and intercel lular adhesion molecule-1 achieved after proinflammatory activation (P < 0. 05), which correlated with a reduction in the real-time association constan ts measured by biosensor techniques. These results indicate that direct con tact with the perflubron liquid phase is not necessary to attenuate inflamm atory responses. Rather, diffusion of perflubron from the alveolar space in to the adjacent pulmonary vascular endothelial layer may modulate neutrophi l adhesion and thereby reduce the rate of infiltration of activated neutrop hils into the injured lung.