TLR7 agonist 21

TLR7 agonist21 (Compound 27B) is a selective activator of Toll-like receptor 7 (TLR7), with an EC50 of 17.53 nM for human TLR7 and 41.7 nM for mouse TLR7. It induces the secretion of pro-inflammatory cytokines, including IL-6, TNF-α, IFN-α1, and IL-4. Acting as a vaccine adjuvant, TLR7 agonist21 enhances IgG and IgA levels, offering protection for mice against influenza virus infection.