Yeast-produced RBD-based recombinant protein vaccines elicit broadly neutralizing antibodies and durable protective immunity against SARS-CoV-2 infection

Massive production of efficacious SARS-CoV-2 vaccines is essential for controlling the ongoing COVID-19 pandemic. We report here the preclinical development of yeast-produced receptor-binding domain (RBD)-based recombinant protein SARS-CoV-2 vaccines. We found that monomeric RBD of SARS-CoV-2 could be efficiently produced as a secreted protein from transformed Pichia pastoris ( P. pastoris ) yeast. Yeast-derived RBD-monomer possessed functional...