As the recent COVID-19 pandemic has made clear, the rapid mass production of vaccinesfor emerging infectious diseases is of paramount importance. The use of the baculovirus/insectcell expression system for in vitro protein expression has been a game changer for vaccineproduction, but it also introduces challenges: transfection can be difficult, needs to be repeatedwith every batch, and the final product requires multiple purification steps to remove the residualbaculovirus. We propose an alternative approach that could side-step the drawbacks associatedwith baculovirus/insect cell expression system: in vivo vaccine production in a scalable insectnon-mammalian genetic model system. We aim to achieve this by using the CRISPR-Cas9system to insert viral antigen genes for human and avian influenza into insects that are alreadymass produced for feed and/or waste management. Both the yellow mealworm (Tenebrio molitor)and the blow fly (Phormia regina) are promising bioreactors for manipulating protein expressionin vivo due to their high metabolism and fecundity, ease of rearing, high resilience, and versatilityin mass production systems (large-scale production facilities already exist for both insects). Unlikeexisting transgenic insect hosts such as cabbage looper larvae, both mealworms and blowfliesare gregarious and can be cost effectively mass-reared at a scale of several tons per day. Byusing the CRISPR-Cas9 technique for recombinant protein expression to express influenzaantigens in these insects, we will engineer life-stage dependent activation of the antigenproduction. Using existing technologies to facilitate rapid antigen protein purification, we willconfirm the antigen production and characterize it. Finally, we will quantify what impact (if any)the modified genome has on phenotypes relevant to mass production and validate costconsiderations for production. This work will set the stage for a steady supply of low-cost andcustomizable antigens, using insect biomass as an affordable and scalable bioreactor.
Public Health Relevance Statement: Project Narrative
Fast and scalable production of vaccine components is urgently needed for protecting public
health against existing and emerging pathogens. In the proposed work we combine our
experience in mass rearing production of insects and genetic engineering with CRISPR-Cas9 to
produce influenza antigens in yellow mealworms and black blow flies. Our approach will
generate a novel non-mammalian genetic model for fast and high-throughput scale vaccine
development.
Project Terms:
