Yellow Fever Virus 17D antigens (YF17D)

The Yellow Fever Virus 17D (YF17D) strain is a highly successful live-attenuated vaccine that serves as a potent stimulus for the host immune system. When expressed in situ, YF17D viral antigens function as a multi-TLR agonist, activating Toll-like receptors 2, 7, 8, and 9 on dendritic cells (Querec et al., 2006, J Exp Med). This activation triggers a robust innate immune response characterized by the production of type I interferons and pro-inflammatory cytokines, which subsequently primes a broad and durable adaptive immune response involving CD4+ and CD8+ T cells as well as B cells (Pulendran, 2009, Nat Rev Immunol). In oncology, this mechanism is leveraged to overcome the immunosuppressive tumor microenvironment, effectively turning cold tumors hot by promoting the infiltration of tumor-specific lymphocytes (Bae et al., 2020, Mol Ther Oncolytics). The YF17D platform is utilized both as a standalone vaccine for yellow fever and as a viral vector for delivering heterologous antigens in cancer immunotherapy and other infectious disease vaccines. While generally safe, the use of YF17D-based therapies requires careful monitoring for rare but serious adverse events such as viscerotropic and neurotropic disease, particularly in immunocompromised populations (CDC, 2023).

Other names

Host immune system via in situ–expressed YF17D viral antigensYF17D vaccine strain antigensYellow Fever 17D-based immunotherapyYF17D viral vector antigens

Activation of multiple Toll-like receptors (TLR2, 7, 8, 9) on dendritic cells to induce broad innate and adaptive immune responses.