A TLR7-agonist nanoparticle adjuvant modulates germinal center responses and promotes a broad antibody response against heterologous viral strains of influenza and SARS-CoV-2

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Presentation Time: 11:30 AM - 12:45 PM
Poster Board Number: B969
Abstract ID: 7831

Presenting Author:
Qian Yin , Assistant Professor

Abstract:

The ideal vaccine against viruses such as influenza and SARS-CoV-2 must provide robust, durable, and broad immune protection against multiple viral variants. However, antibody responses to current vaccines often lack robust cross-reactivity. To tackle this challenge, we develop a polymeric Toll-like receptor 7 agonist nanoparticle (TLR7-NP) adjuvant, which enhances lymph node targeting, promotes persistent immune cell activation, and leads to early germinal center responses. When mixed with alum-adsorbed antigens, this TLR7-NP adjuvant elicits cross-reactive antibodies for both dominant and subdominant epitopes in mice. This TLR7-NP-adjuvanted influenza subunit vaccine successfully protects mice against the viral challenge of a different strain. This strategy also enhances the antibody response to a SARS-CoV-2 subunit vaccine against multiple viral variants that have emerged. Moreover, this TLR7-NP augments antigen-specific immune responses in human tonsil organoids. Overall, we describe a nanoparticle adjuvant to improve immune responses to viral antigens, with promising implications for developing broadly protective vaccines.