The invention relates to immunostimulatory oligonucleotides and methods of using immunostimulatory oligonucleotides to induce an antigen-specific immune response. The invention further relates to a vaccine that comprises an immunostimulatory oligonucleotide and an antigen, and comprises a pharmaceutically acceptable carrier. The immunostimulatory oligonucleotides of the invention, in some embodiments, include one or more modified linkage(s).
