The Role of Complete Freund's Adjuvant in the Immunoprotection of L 2 C Guinea Pig Leukemia

Summary

Leukemia L₂C is a syngeneic guinea pig leukemia which grows progressively in strain 2 guinea pigs. In previous studies, we have demonstrated that immunization of strain 2 guinea pigs with irradiated L₂C cells in aqueous medium or in complete Freund's adjuvant 12 days before lethal leukemic challenge successfully protected almost every animal against leukemia. In the present study, immunization with irradiated L₂C cells in aqueous medium and complete Freund's adjuvant was directly compared using immunization period of shorter duration and challenges with higher numbers of leukemic cells. Under these conditions a distinct advantage to the use of complete Freund's adjuvant was observed with the more rapid development of high levels of tumor immunity. These studies with guinea pig leukemia suggest that in immunotherapy trials of human leukemia, tumor cells or extracts should be administered directly in mycobacterial adjuvants.