CD4 and cancer: We report here for the first time that (a) human DCs treated with recombinant yeast-brachyury can activate previously established human brachyury-specific T-cell lines, (b) recombinant yeast-brachyury–treated DCs can expand human brachyury-specific CD8+ T cells from peripheral blood of healthy donors and cancer patients, and (c) recombinant yeast-brachyury–treated DCs can expand human brachyury-specific CD4+ T cells.