Adxanthromycin: a new inhibitor of ICAM-1/LFA-1 mediated cell adhesion from Streptomyces sp. NA-148

Intercellular adhesion molecule-1 (ICAM-1: CD54) and lymphocyte function-associated antigen-1 (LFA-1: CD11a/CD18) are cell surface adhesion molecules that interact with one another to promote a number of cellular interactions. A search for inhibitors of the ICAM-1/LFA-1 system from microbial metabolites was carried out using two methodologies: a homotypic cell aggregation assay and a cell adhesion assay. During the screening program, we found a new inhibitor, designated adxanthromycin, in the cultured broth of strain Streptomyces sp. NA-148. In this communication we describe the screening, isolation, structure, and biological properties of adxanthromycin.