Browsing by Author "Lee, Audrey"

Now showing 1 - 3 of 3
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    Adjuvanting a subunit SARS-CoV-2 vaccine with clinically relevant adjuvants induces durable protection in mice
    (Springer Nature, 2022-05-23) Grigoryan, Lilit; Lee, Audrey; Walls, Alexandra C.; Lai, Lilin; Franco, Benjamin; Arunachalam, Prabhu S.; Feng, Yupeng; Luo, Wei; Vanderheiden, Abigail; Floyd, Katharine; Wrenn, Samuel; Pettie, Deleah; Miranda, Marcos C.; Kepl, Elizabeth; Ravichandran, Rashmi; Sydeman, Claire; Brunette, Natalie; Murphy, Michael; Fiala, Brooke; Carter, Lauren; Coffman, Robert L.; Novack, David; Kleanthous, Harry; O'Hagan, Derek T.; van der Most, Robbert; McLellan, Jason S.; Suthar, Mehul; Veesler, David; King, Neil P.; Pulendran, Bali; Microbiology and Immunology, School of Medicine
    Adjuvants enhance the magnitude and the durability of the immune response to vaccines. However, there is a paucity of comparative studies on the nature of the immune responses stimulated by leading adjuvant candidates. In this study, we compared five clinically relevant adjuvants in mice-alum, AS03 (a squalene-based adjuvant supplemented with α-tocopherol), AS37 (a TLR7 ligand emulsified in alum), CpG1018 (a TLR9 ligand emulsified in alum), O/W 1849101 (a squalene-based adjuvant)-for their capacity to stimulate immune responses when combined with a subunit vaccine under clinical development. We found that all four of the adjuvant candidates surpassed alum with respect to their capacity to induce enhanced and durable antigen-specific antibody responses. The TLR-agonist-based adjuvants CpG1018 (TLR9) and AS37 (TLR7) induced Th1-skewed CD4+ T cell responses, while alum, O/W, and AS03 induced a balanced Th1/Th2 response. Consistent with this, adjuvants induced distinct patterns of early innate responses. Finally, vaccines adjuvanted with AS03, AS37, and CpG1018/alum-induced durable neutralizing-antibody responses and significant protection against the B.1.351 variant 7 months following immunization. These results, together with our recent results from an identical study in non-human primates (NHPs), provide a comparative benchmarking of five clinically relevant vaccine adjuvants for their capacity to stimulate immunity to a subunit vaccine, demonstrating the capacity of adjuvanted SARS-CoV-2 subunit vaccines to provide durable protection against the B.1.351 variant. Furthermore, these results reveal differences between the widely-used C57BL/6 mouse strain and NHP animal models, highlighting the importance of species selection for future vaccine and adjuvant studies.
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    Mechanisms of innate and adaptive immunity to the Pfizer-BioNTech BNT162b2 vaccine
    (Springer Nature, 2022) Li, Chunfeng; Lee, Audrey; Grigoryan, Lilit; Arunachalam, Prabhu S.; Scott, Madeleine K.D.; Trisal, Meera; Wimmers, Florian; Sanyal, Mrinmoy; Weidenbacher, Payton A.; Feng, Yupeng; Adamska, Julia Z.; Valore, Erika; Wang, Yanli; Verma, Rohit; Reis, Noah; Dunham, Diane; O’Hara, Ruth; Park, Helen; Luo, Wei; Gitlin, Alexander D.; Kim, Peter; Khatri, Purvesh; Nadeau, Kari C.; Pulendran, Bali; Microbiology and Immunology, School of Medicine
    Despite the success of the BNT162b2 mRNA vaccine, the immunological mechanisms that underlie its efficacy are poorly understood. Here we analyzed the innate and adaptive responses to BNT162b2 in mice, and show that immunization stimulated potent antibody and antigen-specific T cell responses, as well as strikingly enhanced innate responses after secondary immunization, which was concurrent with enhanced serum interferon (IFN)-γ levels 1 d following secondary immunization. Notably, we found that natural killer cells and CD8+ T cells in the draining lymph nodes are the major producers of this circulating IFN-γ. Analysis of knockout mice revealed that induction of antibody and T cell responses to BNT162b2 was not dependent on signaling via Toll-like receptors 2, 3, 4, 5 and 7 nor inflammasome activation, nor the necroptosis or pyroptosis cell death pathways. Rather, the CD8+ T cell response induced by BNT162b2 was dependent on type I interferon-dependent MDA5 signaling. These results provide insights into the molecular mechanisms by which the BNT162b2 vaccine stimulates immune responses.
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    A molecular atlas of innate immunity to adjuvanted and live attenuated vaccines, in mice
    (Springer Nature, 2022-01-27) Lee, Audrey; Scott, Madeleine K.D.; Wimmers, Florian; Arunachalam, Prabhu S.; Luo, Wei; Fox, Christopher B.; Tomai, Mark; Khatri, Purvesh; Pulendran, Bali; Microbiology and Immunology, School of Medicine
    Adjuvants hold great potential in enhancing vaccine efficacy, making the understanding and improving of adjuvants critical goals in vaccinology. The TLR7/8 agonist, 3M-052, induces long-lived humoral immunity in non-human primates and is currently being evaluated in human clinical trials. However, the innate mechanisms of 3M-052 have not been fully characterized. Here, we perform flow cytometry, single cell RNA-seq and ATAC-seq to profile the kinetics, transcriptomics and epigenomics of innate immune cells in murine draining lymph nodes following 3M-052-Alum/Ovalbumin immunization. We find that 3M-052-Alum/OVA induces a robust antiviral and interferon gene program, similar to the yellow fever vaccine, which is known to confer long-lasting protection. Activation of myeloid cells in dLNs persists through day 28 and single cell analysis reveals putative TF-gene regulatory programs in distinct myeloid cells and heterogeneity of monocytes. This study provides a comprehensive characterization of the transcriptomics and epigenomics of innate populations in the dLNs after vaccination.