Endothelial cells at inflammatory sites as target for therapeutic intervention

In the course of an inflammation, vascular endothelial cells (VECs) are strongly involved in processes like leukocyte recruitment, cytokine production, and angiogenesis. Specific interference in these processes may yield great therapeutic benefit in the treatment of (chronic) inflammatory disorders. Drug targeting to VECs at inflamed sites may allow such intervention. VECs at inflamed sites represent a very well-accessible target cell population for circulating drug-targeting systems, which may also be selectively distinguished from normal VECs by the expression of several cell surface receptors involved in the inflammation. One group of specifically expressed molecules are the adhesion molecules (AMs), which have a major function in adhesion of cells to each other, to the extracellular matrix, or in the adhesion and subsequent recruitment of circulating immune cells. This review describes AMs with regard to their function in the inflammatory disease and their usefulness in functioning as a specific target receptor for drug-targeting approaches in general and with an emphasis on liposome-based drug delivery.