Cellular uptake of liposomes targeted to intercellular adhesion molecule-1(ICAM-1) on bronchial epithelial cells

Previously, it was demonstrated that immunoliposomes, bearing anti-intercel lular adhesion molecule-1 (ICAM-1) antibodies (mAb F10.2), can specifically bind to different cell types expressing ICAM-1. In this study, we have qua ntified the amount of immunoliposomes binding to IFN-gamma activated human bronchial epithelial cells (BEAS-2B) in vitro and studied the subsequent fa te of cell-bound anti-ICAM-1 immunoliposomes. We demonstrate that binding o f the immunoliposomes to the epithelial cells depends on the liposome conce ntration used. After binding to the cell surface, the anti-ICAM-1 immunolip osomes are rapidly internalised by the epithelial cells. Sixty percent of c ell-bound immunoliposomes were internalised by the epithelial cells within 1 h of incubation at 37 degrees C. The results indicate that ICAM-1 targete d immunoliposomes may be used as carriers for the intracellular delivery of anti-inflammatory drugs to sites of inflammation characterised by an incre ased expression of ICAM-1. (C) 1999 Elsevier Science B.V. All rights reserv ed.