Protection of mice against syngeneic C1300 neuroblastoma challenge by immunization with membranes of C1300 neuroblastoma cells.

Male A/J mice 2-3 months old were inoculated sc with membranes from syngeneic C1300 neuroblastoma cells (clone NB6R) in complete Freund's adjuvant. Significant immunoprophylaxis was noted in the sensitized mice upon sc challenge with viable NB6R cells. During the experiment (60 days from viable cell challenge), each control mouse developed a palpable tumor and died within 50 days. Complete protection was obtained with a program of 4 inoculations of NB6R cell membranes. Each mouse given only 1 inoculation of NB6R cell membranes developed a palpable tumor, but afer 60 days only 1 mouse in 7 had died, which indicated a significant degree of protection. With in vitro tests of lymphocyte proliferation, rosette formation, and complement fixation, it was shown that these mice had mounted both cellular and humoral immune response against the tumor cells.