CpG ODN 2006 is a synthetic oligodeoxynucleotide designed to mimic bacterial DNA, specifically utilizing unmethylated cytosine-guanine (CpG) motifs to stimulate the immune system. As a Class B CpG ODN, it primarily targets Toll-like receptor 9 (TLR9), a key component of the innate immune response, particularly in B cells. This interaction triggers a cascade of signaling pathways, leading to the activation and proliferation of B cells and the production of pro-inflammatory cytokines.