The Herlyn laboratory is developing cancer vaccines that are being evaluated in animal models for their protective activity against tumors before they are administered to cancer patients. The vaccines are composed of antibodies mimicking tumor antigens (anti-idiotypic antibodies) or the antigens expressed in viruses (recombinant adeno- or vaccinia-viruses) and are selected based on their high probability of inducing both humoral and cellular immune responses in patients. The animal models we have developed for preclinical evaluation of the vaccines closely mimic the condition in cancer patients. In other studies which have reached clinical trials, we are evaluating the vaccinated patients' immune responses to their tumors.