Protective Immunity against Gamma and Zeta Variants after Inactivated SARS-CoV-2 Virus Immunization.

Marcilio Jorge Fumagalli,Carlos Fabiano Capato,Vitor Gonçalves Floriano,Patrick Orestes De Azevedo,Vânia Luiza Deperon Bonato,Bruna Amanda Cruz Rattis,Benedito Antônio Lopes Da Fonseca,Simone Gusmão Ramos,Thais Fernanda De Campos Fraga-Silva,Luiz Tadeu Moraes Figueiredo,Ricardo Tostes Gazzinelli,Luiza Antunes Castro-Jorge,Natália Satchiko Hojo-Souza,Julia Teixeira De Castro

doi:10.3390/v13122440

Marcilio Jorge Fumagalli, Carlos Fabiano Capato + Show 12 more

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https://doi.org/10.3390/v13122440

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Journal: Viruses	Publication Date: Dec 4, 2021
Citations: 8	License type: CC BY 4.0

Affiliation: Universidade de São Paulo, Fundação Oswaldo Cruz

Abstract

The persistent circulation of SARS-CoV-2 represents an ongoing global threat due to the emergence of new viral variants that can sometimes evade the immune system of previously exposed or vaccinated individuals. We conducted a follow-up study of adult individuals that had received an inactivated SARS-CoV-2 vaccine, evaluating antibody production and neutralizing activity over a period of 6 months. In addition, we performed mice immunization with inactivated SARS-CoV-2, and evaluated the immune response and pathological outcomes against Gamma and Zeta variant infection. Vaccinated individuals produced high levels of antibodies with robust neutralizing activity, which was significantly reduced against Gamma and Zeta variants. Production of IgG anti-S antibodies and neutralizing activity robustly reduced after 6 months of vaccination. Immunized mice demonstrated cellular response against Gamma and Zeta variants, and after viral infection, reduced viral loads, IL-6 expression, and histopathological outcome in the lungs. TNF levels were unchanged in immunized or not immunized mice after infection with the Gamma variant. Furthermore, serum neutralization activity rapidly increases after infection with the Gamma and Zeta variants. Our data suggest that immunization with inactivated WT SARS-CoV-2 induces a promptly responsive cross-reactive immunity response against the Gamma and Zeta variants, reducing COVID-19 pathological outcomes.

Highlights

Introduction distributed under the terms andSevere acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged in late 2019 in Wuhan, China [1]
To evaluate the immunogenicity of immunization with inactivated SARS-CoV-2, blood samples were collected from individuals before vaccination, and 1, 3, and 6 months after the second vaccine dose with CoronaVac (Figure 1A)
We evaluated immune response after immunization with CoronaVac, an inactivated SARS-CoV-2-based vaccine

Summary

Introduction

Introduction distributed under the terms andSevere acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged in late 2019 in Wuhan, China [1]. SARS-CoV-2 is the causative agent of the coronavirus disease 2019. (COVID-19) pandemic, a human respiratory disease characterized by dry cough, headache, fever, severe pneumonia, and shortness of breath that can rapidly progress to respiratory conditions of the Creative Commons. SARS-CoV-2 has globally infected more than 200 million people, resulting in more than 4 million deaths, representing one of the most human life-threatening species of coronavirus [3]. SARS-CoV-2 belongs to the Betacoronavirus genus from the Coronaviridae family It harbors a positive-sense single-stranded genomic RNA that encodes four structural proteins (spike (S), envelope (E), membrane (M), and nucleocapsid (N)), 16 nonstructural proteins (nsp to nsp16), and several accessory proteins [4]. The S protein is the primary major antigen employed on vaccine development in many distinct platforms [5,6,7]

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