Molecular Aspects Concerning the Use of the SARS-CoV-2 Receptor Binding Domain as a Target for Preventive Vaccines

Valdes-Balbin, Yury; Santana-Mederos, Darielys; Paquet, Françoise; Fernandez, Sonsire; Climent, Yanet; Chiodo, Fabrizio; Rodríguez, Laura; Sanchez Ramirez, Belinda; Leon, Kalet; Hernandez, Tays; Castellanos-Serra, Lila; Garrido, Raine; Chen, Guang-Wu; Garcia-Rivera, Dagmar; Rivera, Daniel G.; Verez-Bencomo, Vicente

[Image: see text] The development of recombinant COVID-19 vaccines has resulted from scientific progress made at an unprecedented speed during 2020. The recombinant spike glycoprotein monomer, its trimer, and its recombinant receptor-binding domain (RBD) induce a potent anti-RBD neutralizing antibody response in animals. In COVID-19 convalescent sera, there is a good correlation between the antibody response and potent neutralization. In this review, we summarize with a critical view the molecular aspects associated with the interaction of SARS-CoV-2 RBD with its receptor in human cells, the angiotensin-converting enzyme 2 (ACE2), the epitopes involved in the neutralizing activity, and the impact of virus mutations thereof. Recent trends in RBD-based vaccines are analyzed, providing detailed insights into the role of antigen display and multivalence in the immune response of vaccines under development.