Antibodies are disclosed which bind specifically to P-selectin, block the binding of PSGL-1 to P-selectin, and cause dissociation of preformed P-selectin/PSGL-1 complexes. The disclosure identifies a heretofore unrecognized, near N-terminal, antibody binding domain (a conformational epitope) of P-selectin to which the antibodies (which may be chimeric, human or humanized antibodies for example) bind. Antibodies are disclosed which bind to the conformational epitope of P-selectin and which have a dual function in blocking binding of PSGL-1 to P-selectin, and in causing dissociation of preformed P-selectin/PSGL-1 complexes. Such dual function anti-P-selectin antibodies and binding fragments thereof may be used in the treatment of a variety of acute and chronic inflammatory and thrombotic disorders and conditions. Screening methods for identifying and characterizing such antibodies are also disclosed.
