Role of intercellular adhesion molecule 1 in acute lung injury induced by candidemia.

Candidemia, a complication often affecting immunocompromised patients, is a common cause of acute lung injury. Yeast-phase Candida albicans has been shown to express a protein that is antigenically and structurally related to Mac-1. C. albicans is reported to stimulate intercellular adhesion molecule 1 (ICAM-1) expression on endothelial cells. In this study, the authors examined the role of ICAM-1 in acute lung injury induced by candidemia. The authors cultured rat pulmonary artery endothelial cells (RPAEC) and investigated the effect of anti-ICAM-1 antibodies on adhesion of C. albicans to RPAEC. In addition, the authors administered anti-ICAM-1 antibodies to rats to examine the effect of the antibodies on experimentally induced candidemia. Survival rates, lung wet-to-dry (W/D) weight ratios, bronchoalveolar lavage (BAL) fluid, histopathological findings, and colony-forming units (CFUs) of lung C. albicans were examined. The adherence of C. albicans to RPAEC was significantly decreased by anti-ICAM-1 antibodies. Anti-ICAM-1 antibodies significantly increased survival, decreased lung W/D weight ratios, decreased neutrophil counts in the BAL fluid, reduced microscopic lung injury, and decreased the quantity of lung C. albicans. These results indicate that ICAM-1 plays a role in adherence of C. albicans to pulmonary vascular endothelial cells, which likely leads to invasion of lung tissue by the organism.