Bacteriophage T4 Vaccine Platform for Next-generation Influenza Vaccine Development

Abstract

Developing influenza vaccines that protect against a broad range of viruses is a public health priority, and several conserved viral proteins or domains have been identified as promising targets for such vaccine development. However, none of the targets is immunogenic, and vaccine platforms that can incorporate multiple antigens with enhanced immunogenicity are desperately needed. In this study, we provided proof-of-concept for the development of next-generation influenza vaccine using T4 phage virus-like particle (VLP) platform. With extracellular domain of influenza matrix protein 2 (M2e) as a readout, we showed that more than 1,280 M2e molecules can be assembled on a 120×90 nanometer phage capsid to form T4-M2e VLPs, which are highly immunogenic and induced complete protection against influenza virus challenge without any addition adjuvant. Potentially, additional conserved antigens or molecular adjuvants could be incorporated into the T4-M2e VLPs to customize influenza vaccines to address different issues. All the components of T4 VLP vaccines can be mass-produced in E. coli in a short time, therefore, providing a rapid approach to deal with the potential influenza pandemic.

A bacteriophage-based, highly efficacious, needle and adjuvant-free, mucosal COVID-19 vaccine

“…Microbiome analyses showed no significant changes in the microbiome diversity in mice vaccinated with the T4-CoV-2 vaccine. In human clinical trials and hundreds of T4 phage vaccine immunizations over the years involving mice, rats, rabbits, and macaque animal models and diverse antigens such as anthrax, plague, and HIV did not identify any significant side effects (Li et al, 2021; Rao et al, 2011b; Tao et al, 2013; Tao et al, 2018a; Zhu et al, 2019). Furthermore, the T4 phage is one of the most stable virus scaffolds known (Jończyk et al, 2011) and our stability studies showed that the T4-CoV-2 vaccine was completely stable at ambient temperature for at least 10-weeks.…”

Rapid Development of a Mucosal Nanoparticle Flu Vaccine by Genetic Engineering of Bacteriophage T4 using CRISPR-Cas

“…Previously, we used an in vitro assembly system to display antigen-Soc fusion proteins on T4 capsid by mixing the fusion proteins with Hoc -Soc -T4 phages. [15][16][17]24] The highly efficient phage genome editing technology recently developed using CRISPR-Cas allowed us to display foreign proteins on T4 capsid in vivo by inserting the coding sequence into T4 genome in-frame at the C terminus of Soc gene. [19,21,25] During the propagation of recombinant T4 phages in E. coli, expressed Soc-antigen proteins are expected to assemble on T4 capsids to form antigendecorated nanoparticles.…”

“…[15,16,18,19] The generated nanoparticles without any adjuvant induced robust systemic immune responses and provided complete protections against challenge in different animal models, indicating the potent intrinsic adjuvant activity of phage T4. [15,16] Recent studies indicated that phage T4 can be enriched in mucus layer on mucosal surfaces of human and all other tested animals through binding to mucin glycoproteins, which increases the chance to interact with their bacterial hosts. [20] The mucoadhesive feature of phages along with their intrinsic adjuvant activities could be a defense mechanism of metazoan against invasive bacteria.…”

“…[14] Recently, we developed a nanoparticle vaccine platform using T4 phage based on the highaffinity interactions between the small outer capsid protein (Soc) and capsid. [15][16][17] Soc-fused antigens from plague, anthrax, influenza, and SARS-CoV2 were assembled on the surface of T4 capsid by incubating the recombinant fusions with soc -T4 phage in vitro. [15,16,18,19] The generated nanoparticles without any adjuvant induced robust systemic immune responses and provided complete protections against challenge in different animal models, indicating the potent intrinsic adjuvant activity of phage T4.…”

“…[15][16][17] Soc-fused antigens from plague, anthrax, influenza, and SARS-CoV2 were assembled on the surface of T4 capsid by incubating the recombinant fusions with soc -T4 phage in vitro. [15,16,18,19] The generated nanoparticles without any adjuvant induced robust systemic immune responses and provided complete protections against challenge in different animal models, indicating the potent intrinsic adjuvant activity of phage T4. [15,16] Recent studies indicated that phage T4 can be enriched in mucus layer on mucosal surfaces of human and all other tested animals through binding to mucin glycoproteins, which increases the chance to interact with their bacterial hosts.…”