SBIR Phase I: Stabilization of the desired epitopes of hRSV-F protein for efficient absorption through the gut

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase I project will be to provide global populations with a safe, affordable and viable edible vaccine against the human respiratory syncytial virus (hRSV). hRSV is a critical global health problem, annually affecting 64 million people and causing over 160,000 death, motivating a vaccine. Natural food-derived vaccines offer advantages over traditional injections by providing a safe, affordable, non-invasive, non-egg-based (reduced allergenic risk), vegan-friendly, effective and efficient antigen-delivery system. The project addresses this need by developing a cherry-tomato-based oral vaccine that can be administered painlessly in a chewable gummy-like pill formulation or in oral drops. The proposed fruit-vaccines will minimize the global incidence of hRSV through scalable production and distribution, increasing global accessibility and vaccination rates. Furthermore, with fewer disposables it is more environmentally friendly. This method could apply broadly to other oral-delivery platforms. This Phase I project will advance peptide-based oral-delivery platforms. The project will improve the yield and consistent expression of the immunogenic antigen (hRSV-F protein) in the plant, both pre- and post-harvest, as well as before and after delivery into the body. The approach involves bioengineering the plant-optimized gene for the hRSV-F protein to improve its stability by blocking undesirable cleavage sites while retaining the desirable protective epitopes of the hRSV-F immunogen. Transgenic plants expressing the stabilized hRSV-F in the tomato fruits will be grown in a greenhouse. The hRSV-F-containing cherry-tomatoes will be harvested, homogenized (pureed), and then lyophilized (freeze-dried) to formulate innovative vaccine purees or pills, respectively. Tasks include conducting qualitative and quantitative analyses, such as color, consistency, pH, concentration of intact hRSV-F protein, its potential degradation products and desired epitope/s, analyzed using enzyme-linked immunosorbent assay (ELISA), western-blot and high-performance liquid chromatography. These tests will help characterize the persistence and effectiveness of the proposed changes on hRSV-F protein expression, yield, and stability in fresh-fruits, tomato-puree and in the freeze-dried fruit-pills. Similar assessments will be performed also post-ingestion, in the gut contents and in blood of mice. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.