Induction of resistance to L1210 leukemia in BALB/c X DBA/2Cr F1 mice, with L1210 cells treated with glutaraldehyde and concanavalin A.

Immunization with L1210 mouse leukemia cells treated with glutaraldehyde and concanavalin A resulted in the induction of leukemia-specific immune resistance in BALB/c X DBA/2Cr F1 mice. This was measured by survival of the mice after challenge either with the intact cells or with modified leukemia cells of less malignancy. Factors involved in the induction of immunoprophylaxis were analyzed. To produce an immune response against L1210 cells, preincubation with both glutaraldehyde and concanavalin A was required. Repeated sensitization with this combination produced higher incidences of survivors upon subsequent challenge with L1210 cells than did a single sensitization by equivalent or larger doses. However, the sensitization was rendered less effective by repetition of the immunization process five times.