Vaccination with carbohydrate peptide mimotopes promotes anti-tumor responses

Tumor-associated carbohydrate (TAC) antigens are important targets in cance r vaccine efforts. Carbohydrates are, however, frequently poor immunogens, in that they are T-cell-independent antigens. Molecular mimicry of TAC by p eptides is an alternative approach to generating anti-carbohydrate immune r esponses. Here we demonstrate that peptide mimotopes can elicit antibody re sponses that cross-react with representative human TAC antigens. Primary im munization with such a multiple antigenic peptide, along with QS-21 as adju vant, elicits cytotoxic antibodies reactive with naturally occurring forms of TAC expressed on tumor cells, and vaccination of mice with peptide mimot opes reduced tumor growth and prolonged host survival in a murine tumor mod el.