Comparison of 16 human colon carcinoma celllines for their expression of sialyl Le X antigens and their E-selectin-dependent adhesion

Two anti-sialyl Lewis X (sLe X ) monoclonal antibodies, mAb FH6 and mAb KM93, were analyzed by flowcytometry for their ability to bind to 16 human colon carcinoma cells. The binding profiles of these twoanti-sLe X monoclonal antibodies did not correspond to each other. Three of the cell lines were reactive withmAb FH6 but not with mAb KM93. These three cell lines did not adhere to Chinese hamster ovary cellsthat were stably transfected with human E-selectin cDNA in an E-selectin-dependent manner. In contrast,almost all human colon carcinoma cell lines that bound to mAb KM93 adhered to cells that expressedE-selectin. These results suggest that a subtype of sLe X carbohydrate epitopes recognized by mAb FH6 donot always function as ligands for E-selectin.© Kluwer Academic Publishers