Tobacco-based sustainable squalene for novel vaccine adjuvant emulsions

This Project Grant award from the National Institute of Allergy and Infectious Diseases supports the development of a novel plant-based source for squalene as a natural vaccine adjuvant. The $514,006 award to Synshark LLC supports research to engineer tobacco plants to stably produce and accumulate squalene on their leaves. This work directly relates to the commercialization plan to provide a non-animal, indoor grown natural adjuvant for vaccines. Currently, squalene used in vaccines is sourced from sharks, which presents sustainability and public acceptance challenges. The goal of this research is to demonstrate the feasibility of producing squalene directly in tobacco leaves for use as a vaccine adjuvant. If successful, this work could provide a renewable plant-based source of this important adjuvant. The award falls under the Allergy and Infectious Diseases Research program (CFDA 93.855), which aims to support biomedical research and training in infectious diseases.

Abstract

In this grant application, synshark (SBA certified small business), in collaboration with north carolina state university, will demonstrate a new plant source for pharmaceutical grade squalene as a natural adjuvant. The team will utilize novel plant-engineering routes to stabilize squalene yields in tobacco, and discover methods to manufacture and isolate the molecule for rapid pandemic response. This research matches the interests of the national institute of allergy and infectious diseases (niaid) with three of its divisions: division of aids (daids), division of allergy, immunology and transplantation (dait) and division of microbiology and infectious diseases (dmid). Specific branches and programs under these divisions with relevant statements of needs are: (i) the vaccine research program (daids), (II) basic immunology branch (dait), (III) sbir adjuvant research program - bacteriology and mycology branch (dmid). The ultimate goal of this activity is the successful commercialization and public benefit of a rapidly derived natural adjuvant based on plant squalene which is completely biocompatible. Adjuvants have a key role in promotion of vaccine efficacy through eliciting a stronger immune response and reducing the volumetric need of active ingredient. By all accounts, evidence was available that sars-COV-1 immunity relied on t-cell activation and that vaccines should account for that. Synthetic adjuvants being used by the current regulated sars-COV-1 vaccines are not simulating a strong t-cell response, while natural squalene known to enhance the magnitude of the t-cell response. But pharmaceutical squalene is sourced from shark 'livering', conveying: 1) the risk of associated pollutants and pathogens, and 2) public resistance. On the other hand, the other natural adjuvant quillaja saponaria oil, costs IT's manufacture fujifilm diosynth (in the novavax sars-COV-1 vaccine) more than $100,000 per kilogram. This has led to fujifilm diosynth's support of this application. Through terpenoid metabolic engineering, synshark has already managed to successfully shift the fundamental carbon allocation pathways within tobacco allowing for increased accumulation of the triterpene squalene. The phase i tasks being introduced are directly related to the commercialization plan to deliver to the market a non-animal sourced natural adjuvant which is grown indoors through proven tobacco pharmaceutical techniques. The phase i period is planned to take this innovative and disruptive terpene sourcing technology to fruition by enabling the application of synshark's research advancements in molecular genetics. During phase i, the tobacco plant will be engineered to study the feasibility of squalene production directly on the leaf surface by placing the constructs under trichome-specific promoters, thereby stabilizing yield in a manner best suited for controlled indoor growing. In the phase II period, synshark, through committed collaborators, will establish scalability of manufacturing and purification under US food and drug administration guidelines.