A novel P-selectin ligand glycoprotein is disclosed, comprising the amino acid sequence set forth in SEQ ID NO:2 or by the amino acid sequence set forth in SEQ ID NO:4. DNA sequences encoding the P-selectin ligand protein are also disclosed, along with vectors, host cells, and methods of making the P-selectin ligand protein. Pharmaceutical compositions containing the P-selectin ligand protein and methods of treating inflammatory disease states characterized by P-selectin- and E-selectin-mediated intercellular adhesion are also disclosed.