A Booster Dose of CoronaVac Increases Neutralizing Antibodies and T Cells that Recognize Delta and Omicron Variants of Concern
Bárbara M. Schultz, Felipe Melo-González, Luisa F. Duarte, Nicolás M. S. Gálvez, Gaspar A. Pacheco, Jorge A. Soto, Roslye V. Berríos-Rojas, Liliana A González, Daniela Moreno‐Tapia, Daniela Rivera-Pérez, Mariana Ríos, Yaneisi Vázquez, Guillermo Hoppe-Elsholz, Catalina A. Andrade, Omar P. Vallejos, Alejandro Piña-Iturbe, Carolina Iturriaga, Marcela Urzúa, María S Navarrete, Álvaro Rojas, Rodrigo Fasce, Jorge Onrubia Fernández, Judith Mora, Eugenio Ramı́rez, Aracelly Gaete-Argel, Mónica L. Acevedo, Fernando Valiente‐Echeverría, Ricardo Soto‐Rifo, Daniela Weiskopf, Alba Grifoni, Alessandro Sette, Gang Zeng, Weining Meng, CoronaVac03CL Study Group, José Vicente González-Aramúndiz, Pablo A. González, Katia Abarca, Alexis M. Kalergis, Susan M. Bueno
Abstract
T cell responses were increased following the booster dose. In contrast, levels of gamma interferon secretion and T cell activation against the VOCs Delta and Omicron were not significantly different from those for the ancestral strain. Therefore, a third dose of CoronaVac in a homologous vaccination schedule improves its immunogenicity in healthy volunteers.