The project aims at identifying surface proteins that are modified by the tetrasaccharide sialyl Lewisa/x and therefore serve as selectin ligands in Multiple Myeloma. To that end, we have performed an immunoprecipitation using the Heca452 antibody (which recognizes sialyl Lewisa/x-related structures) and a matched isotype control on membrane-enriched fractions that have been generated from the sialyl Lewisa/x-enriched and parental Multiple Myeloma cell line MM1S and RPMI8226. Using this approach, we have been able to identify candidate proteins that may function as selectin ligands in myeloma.