TLR-9 agonist immunostimulatory sequence adjuvants linked to cancer antigens

The primary goal of cancer vaccines is to elicit tumor-specific cytotoxic T lymphocytes (CTL) capable of eradicating established tumors and preventing/eradicating their metastatic spread. CpG oligonucleotides (CpG ODN) activate and support the maturation of immune cells, including plasmacytoid dendritic cells and B lymphocytes, that express Toll-like receptor 9 (TLR9) and are capable of presenting tumor antigens to T cells. Thus, CpG ODN are effective vaccine adjuvants. The adjuvant activity of CpG ODN is improved by maintaining them in close physical and temporal proximity to the co-administered vaccine antigen. This work describes a method of chemically conjugating CpG ODN to antigens and/or cancer cells that improve the resulting CTL response.