Antibodies as carriers for oncostatic materials.

Daunomycin conjugates to antitumor antibodies prepared either by direct binding or by binding via dextran retain both the antibody and the drug activity. Thus, the exert specific cytotoxicity in vitro toward tumor cells that the antibodies recognize. The macromolecular conjugates are able to penetrate the cells and concentrate in or on the nuclei. In vivo, the antitumor antibodies accumulate preferentially at the tumor metastases. Daunomycin-antibody conjugates are more active than the free drug in prolongation of survival of mice transplanted with the YAC lymphoma cells.