GROWTH OF TRANSPLANTED RAT TUMORS FOLLOWING ADMINISTRATION OF CELL-FREE TUMOR ANTIGENS

  • 1 January 1978
    • journal article
    • research article
    • Vol. 38  (5) , 1208-1212
Abstract
The variable effect of immunizations with cell-free tumor extract (TE) in a weakly antigenic (Morris hepatoma 3924a) and a highly antigenic (glioma 9L) inbred rat model system was described. Tumor enhancement was noted with the weakly antigenic tumor following immunization with a low dose of TE admixed with Freund''s adjuvant or immunization with high doses of TE. Enhancement was observed at 4 tumor cell challenge levels. Tumor enhancement with the highly antigenic tumor was found at only 1 level and was seen following immunization with intermediate doses of TE and a high tumor cell challenge. Tumor protection was only detected with the weakly antigenic tumor following immunizations with an intermediate dose of TE and challenge with a tumor cell dose 5-fold over threshold. This protection was tumor specific, as judged by an amputation and rechallenge experiment.