Tumor location and drug targeting using a monoclonal antibody (anti-SSEA-1) and antigen-binding fragments.

Both murine and heterotransplanted human nonseminomatous germ-cell tumors have been successfully located by external scintigraphy using radioiodinated anti-SSEA-1, a monoclonal IgM, and its pepsin-derived antigen-binding fragment, F(ab')2 mu. Antibody localization in the tumor is mainly due to antigenic specificity, rather than to nonspecific trapping, and depends strongly on the amount of time after injection. The antibody has been used for drug targeting in vitro and in vivo.