IMMUNOSTIMULATORY OLIGODEOXYNUCLEOTIDES CONTAINING THE CPG MOTIF ARE EFFECTIVE AS IMMUNE ADJUVANTS IN TUMOR-ANTIGEN IMMUNIZATION

Recent advances in our understanding of the immune response are allowi ng for the logical design of new approaches to cancer immunization, On e area of interest is the development of new immune adjuvants, Immunos timulatory oligodeoxynucleotides containing the CpG motif (CpG ODN) ca n induce production of a wide variety of cytokines and activate B cell s, monocytes, dendritic cells, and NK cells, Using the 38C13 B cell ly mphoma model, we assessed whether CPG ODN can function as immune adjuv ants in tumor antigen immunization, The idiotype served as the tumor a ntigen. Select CpG ODN were as effective as complete Freund's adjuvant at inducing an antigen-specific antibody response but were associated with less toxicity, These CpG ODN induced a higher titer of antigen-s pecific IgG2a than did complete Freund's adjuvant, suggesting an enhan ced TH1 response. Mice immunized with CpG ODN as an adjuvant were prot ected from tumor challenge to a degree similar to that seen in mice im munized with complete Freund's adjuvant. We conclude that CpG ODN are effective as immune adjuvants and are attractive as part of a tumor im munization strategy.