Figure 2. Mechanism by which CpG oligodeoxynucleotides facilitate innate and adaptive immune responses.
CpG ODNs directly activate pDCs and B cells. The resultant immune response is characterized by the production of proinflammatory and Th1 cytokines and polyreactive immunoglobulin. This innate immune response forms a foundation on which antigen-specific adaptive immunity is based. By improving the function of professional APCs, CpG ODNs facilitate the generation of humoral and cellular adaptive immune responses against coadministered vaccine antigens.
APC: Antigen-presenting cell; CTL: Cytotoxic T lymphocyte; ODN: Oligodeoxynucleotide; pDC: Plasmacytoid dendritic cell; TNF: Tumor necrosis factor.