Tumor localization of radiolabeled antibodies raised by a mouse plasma cell tumor

Antibodies raised in rabbits against a mouse plasma cell tumor were labeled with 131 I and injected along with normal rabbit globulin labeled with 125 I into plasmacytoma bearing mice and the degree of localization of the antibodies in the tumors determined. There was localization of the anti-tumor antibody above the background localization of the normal globulins. The localization apparently took place largely on the tumor cell surfaces since following cell fractionation experiments the fixation was found to be largely in the microsome fraction. The antibodies raised against the tumor also showed localization in liver, spleen and brain.