Vertical farming of duckweed: advancing edible vaccine production for global health

The development of vaccines has significantly advanced public health by preventing infectious diseases. However, traditional vaccines face challenges such as the need for injections, trained personnel, and cold storage. Plant-derived edible vaccines present a promising alternative, offering cost-effectiveness, scalability, and the ability to induce mucosal immunity. Duckweeds (Lemnaceae), with their high protein content and rapid growth, have received interest in producing these vaccines. Transgenic duckweed expressing pathogenic antigens has demonstrated efficacy in animal models, eliciting both mucosal and systemic immune responses. Despite their potential, large-scale production of duckweed-based vaccines faces challenges, including spatial requirements, water usage, and contamination risks. To address these issues, we propose a vertical farming and recirculation system. This system minimizes space and water usage, enhances light exposure through transparent, retractable trays, and integrates solar panels for energy efficiency. Additionally, utilizing livestock and poultry farm wastewater as a growth medium offers a sustainable solution. Our proposed value chain involves transforming duckweed with molecular bioengineering techniques, cultivating it vertically, and processing it into a powder for food or feed. This approach promises to enhance vaccine accessibility by lowering storage requirements, as the powdered biomass does not need to be refrigerated. This could reduce costs and contribute to global public health efforts. Still, purification steps before vaccine usage and potential regulatory concerns are yet to be addressed.