ENHANCED INDUCTION OF IMMUNE RESISTANCE BY CONCANAVALIN A-BOUND L1210 VACCINE AND AN IMMUNOPOTENTIATOR PREPARED FROM CORIOLUS-VERSICOLOR

Abstract

Combined administration of a vaccine consisting of a small number (2 .times. 106) of L1210 murine leukemic cells treated with glutaraldehyde and concanavalin A and a protein-bound polysaccharide preparation of C. versicolor induced synergistic resistance to L1210 leukemia in BALB/c .times. DBA/2Cr F1 mice. This effect was dependent on the dose and timing of the administration of the protein-bound polysaccharide preparation, being most effective at the time of or 1 day after the 2nd vaccination. Induced resistance was not cross-reactive with P388 murine leukemia, indicating specificity of resistance. This immunopotentiation by the protein-bound polysaccharide did not occur when L1210 cells treated with glutaraldehyde, but not with concanavalin A, were used as a vaccine.