Induction of Prophylactic, Theraputic, and Cytotoxic Activity using Solubized Tumor Antigens

Abstract

Immunoprophylaxis was developed in syngeneic C3H/Strong mice against ip implants of spontaneous (MTV) induced mouse mammary tumor by sensitization of the host with id injections of solubilized 3 M KCl antigens of transplantable mammary tumor. Ten days after the.2nd id injection of 3 M KCl antigens mice were challenged ip with 5 x 104 viable tumor cells. Optimal protection was found after pretreatment with 3 M KCl solubilized tumor anti-gens (1. 0 mg. protein) with BCG (2-8 x 104 Tice organisms) as evi­ denced by a 60% survival after 120 days. Control groups with 5 x 104 cells ip died in 38 +/- 2 days. A maximum immunizing dose of 5.0 mg. 3 M KCl antigens elicited virtually no effect upon animal survival with animals dying within 3-5 days of the control. A program solely of immunotherapy with 3 M KCl solubilized tumor antigens+ BCG (1. 0 mg. 3 M KCl antigens+ 2-8 x 104 Tice organisms id weekly) was administered to mice days 0, l, 3, and 7 after ip inoculation of 5 x 104 viable tumor cells. Treatment with 3 M KCl antigens+ BCG on day 0 and day 1 controlled tumor growth with 80-90% being free of neoplastic disease at 120 days. Therapy begun on day 7 led to 100% mortality by day 47. Treatment with BCG alone led to tumor enhancement with 100% death in 32+/- 2 days.