Improved vaccine production by engineering the agroinfiltration platform

This proposal aims to revolutionize vaccine production in plants. Vaccines can be quickly and efficiently produced in plants through agroinfiltration of Nicotiana benthamiana to produce virus-like particles (VLPs), a technique that has already been used industrially to produce a vaccine against Covid-19, called CoVLP. This platform, however, has three major limitations that restricts its usefulness leading to low yields. We offer solutions to each of these limitations.

First, we seek to prevent crosslinking in extracts, a major issue during VLP purification. We have preliminary evidence that polyphenol oxidases (PPOs) are responsible and we aim to confirm this, improve VLP purification for various viruses, and create PPO knockout plants for wider use.

Second, we aim to stop undesired, premature cleavage of the Spike protein of SARS-CoV-2. We plan to pinpoint where and how cleavage occurs and have identified 15 groups of proteases that might be responsible for cleavage. We will deplete these candidate proteases through gene silencing and genome editing to generate plants with reduced Spike protein cleavage.

Third, we intend to enhance Spike protein folding by exploring alternative chaperones, including lectin-based chaperones, protein prolyl isomerases (PPIs), and protein disulfide isomerases (PDIs). These will optimize Spike protein production, known for its folding complexity.

This project holds immense potential for low-income countries, offering cost-effective vaccine production not reliant on extensive industrial infrastructure. We commit to freely provide genetic materials and sharing research findings, benefiting small-scale vaccine programs in low-income countries and the broader plant research community. Ultimately, this proposal seeks to improve vaccine accessibility and production efficiency, potentially reshaping global healthcare.