Ambient Temperature Stable, Scalable COVID-19 Polymer Particle Vaccines Induce Protective Immunity.

There is an unmet need for safe and effective severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines that are stable and can be cost-effectively produced at large scale. Here, a biopolymer particle (BP) vaccine technology that can be quickly adapted to new and emerging variants of SARS-CoV-2 is used. Coronavirus antigen-coated BPs are described as vaccines against SARS-CoV-2. The spike protein subunit S1 or epitopes from S and M proteins (SM) plus/minus the nucleocapsid protein (N) are selected as antigens to either coat BPs during assembly inside engineered Escherichia coli or BPs are engineered to specifically ligate glycosylated spike protein (S1-ICC) produced by using baculovirus expression in insect cell culture (ICC). BP vaccines are safe and immunogenic in mice. BP vaccines, SM-BP-N and S1-ICC-BP induced protective immunity in the hamster SARS-CoV-2 infection model as shown by reduction of virus titers up to viral clearance in lungs post infection. The BP platform offers the possibility for rapid design and cost-effective large-scale manufacture of ambient temperature stable and globally available vaccines to combat the coronavirus disease 2019 (COVID-19) pandemic.

Protein Expression in the Baculovirus-Insect Cell Expression System.

The baculovirus-insect cell expression system is a popular choice for recombinant protein production. Post-translational modifications, production of protein complexes, and reported high protein yields are some of the favorable features of this eukaryotic expression system. The intricacies of the baculovirus-insect cell expression system may deter beginners from implementing it for routine protein production. This chapter documents a detailed protocol for using the baculovirus-insect cell expression system, which has been verified in a protein production research facility.