CpG motif–containing DNA, Toll-like receptor 9 agonist (in the context of adjuvant BC02) (CpG ODN (ODN = oligodeoxynucleotide))

CpG oligodeoxynucleotide motifs are short, synthetic single-stranded DNA sequences that contain unmethylated cytosine-guanosine dinucleotides and mimic bacterial DNA patterns. These motifs are recognized by Toll-like receptor 9 (TLR9), primarily expressed on plasmacytoid dendritic cells and B cells. Upon binding, CpG ODN triggers signaling pathways (e.g., MyD88, MAPK, NF-κB) leading to the production of proinflammatory cytokines and maturation of antigen-presenting cells, thereby stimulating both humoral and cellular arms of the immune response. BC02 is a compound adjuvant consisting of BCG-derived CpG DNA and aluminum hydroxide, designed to synergistically enhance immune responses to co-administered vaccines, facilitating robust Th1 and Th2 immunity and increased antigen-specific antibody production. CpG-containing adjuvants are used in licensed vaccines (e.g., HEPLISAV-B) and explored for infectious diseases, cancer immunotherapy, and allergy immunotherapy.

Other names

CpG DNACpG ODNunmethylated CpG oligodeoxynucleotidesTLR9 agonistBCG CpG DNABC02 adjuvantCpG-based adjuvant

Activation of Toll-like receptor 9 (TLR9) on plasmacytoid dendritic cells and B cells; Induction of innate and adaptive immune responses; Enhancement of Th1/Th2 cytokine production; Upregulation of co-stimulatory molecules; Activation of NF-κB and MAPK pathways in immune cells.