SARS-CoV-2 RBD-Tetanus Toxoid Conjugate Vaccine Induces a Strong Neutralizing Immunity in Preclinical Studies

Yury Valdes-Balbin (1) , Darielys Santana-Mederos (1) , Lauren Quintero (1) , Sonsire Fernández (1) , Laura Rodriguez (1) , Belinda Sanchez Ramirez (2) , Rocmira Perez-Nicado (1) , Claudia Acosta (1) , Yanira Méndez (3) , Manuel Ricardo (3) , Tays Hernandez (2) , Gretchen Bergado (2) , Franciscary Pi (2) , Annet Valdes (2) , Tania Carmenate (2) , Ubel Ramirez (1) , Reinaldo Oliva (1) , Jean-Pierre Soubal (1) , Raine Garrido (1) , Felix Cardoso (1) , Mario Landys (1) , Humberto Gonzalez (1) , Mildrey Farinas (1) , Juliet Enriquez , Enrique Noa , Anamary Suarez , Cheng Fang , Luis Espinosa (4) , Yassel Ramos (4) , Luis Javier González (4) , Yanet Climent (1) , Gertrudis Rojas (2) , Ernesto Relova-Hernández (2) , Yanelys Cabrera Infante (2) , Sum Lai Losada (2) , Tammy Boggiano (2) , Eduardo Ojito (2) , Kalet León (2) , Fabrizio Chiodo (5, 6, 1) , Françoise Paquet (7) , Guang-Wu Chen (8, 1) , Daniel Rivera (1) , Dagmar Garcia-Rivera (1) , Vicente Verez Bencomo (1)

1 Finlay Institute of Vaccines
2 Center of Molecular Immunology, Havana
3 UH - University of Havana (Universidad de la Habana)
4 CIGB - Center for Genetic Engineering and Biotechnology [Cuba]
5 VU - Vrije Universiteit Amsterdam [Amsterdam]
6 CSIC - Consejo Superior de Investigaciones Cientificas [España] = Spanish National Research Council [Spain]
7 CBM - Centre de biophysique moléculaire
8 SCU - Sichuan University [Chengdu]

Controlling the global COVID-19 pandemic depends, among other measures, on developing preventive vaccines at an unprecedented pace. Vaccines approved for use and those in development intend to elicit neutralizing antibodies to block viral sites binding to the host's cellular receptors. Virus infection is mediated by the spike glycoprotein trimer on the virion surface via its receptor binding domain (RBD). Antibody response to this domain is an important outcome of immunization and correlates well with viral neutralization. Here, we show that macromolecular constructs with recombinant RBD conjugated to tetanus toxoid (TT) induce a potent immune response in laboratory animals. Some advantages of immunization with RBD-TT conjugates include a predominant IgG immune response due to affinity maturation and long-term specific B-memory cells. These result demonstrate the potential of the conjugate COVID-19 vaccine candidates and enable their advance to clinical evaluation under the name SOBERANA02, paving the way for other antiviral conjugate vaccines.

Domaines: Sciences du Vivant [q-bio]

Yury Valdes-Balbin, Darielys Santana-Mederos, Lauren Quintero, Sonsire Fernández, Laura Rodriguez, et al.. SARS-CoV-2 RBD-Tetanus Toxoid Conjugate Vaccine Induces a Strong Neutralizing Immunity in Preclinical Studies. ACS Chemical Biology, 2021, 16 (7), pp.1223-1233. ⟨10.1021/acschembio.1c00272⟩. ⟨hal-03443835⟩