ABSTRACT
In the original publication [...].
ABSTRACT
Due to a large number of mutations in the spike protein and immune escape, the Omicron variant (B.1.1.529) has become a predominant variant of concern (VOC) strain. To prevent the disease, we developed a candidate inactivated vaccine (Omicron COVID-19 Vaccine (Vero Cell), Inactivated). To evaluate the safety of the vaccine, we tested the repeat-dose toxicity in Sprague-Dawley (SD) rats. The doses were administered randomly to three groups: physiological saline solution (control), aluminum adjuvant in PBS solution adjuvant (adjuvant group), and low-dose and high-dose omicron vaccines (vaccine group) for 6 weeks. The SD rats were allowed to recover for 4 weeks after withdrawal. We evaluated the physiological condition of the rats, including their ophthalmological condition, body weight, food intake, body temperature, blood biochemistry, urine, neutralizing antibody, inflammation at the injection site, and organs weight. In summary, no dose-dependent adverse toxicological changes were observed, and a recovery trend was obvious, which proved the preclinical safety of the candidate omicron vaccine and provided evidence for clinical trials in humans. [ FROM AUTHOR] Copyright of COVID is the property of MDPI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)
ABSTRACT
Due to a large number of mutations in the spike protein and immune escape, the Omicron variant (B.1.1.529) has become a predominant variant of concern (VOC) strain. To prevent the disease, we developed a candidate inactivated vaccine (Omicron COVID-19 Vaccine (Vero Cell), Inactivated). To evaluate the safety of the vaccine, we tested the repeat-dose toxicity in Sprague-Dawley (SD) rats. The doses were administered randomly to three groups: physiological saline solution (control), aluminum adjuvant in PBS solution adjuvant (adjuvant group), and low-dose and high-dose omicron vaccines (vaccine group) for 6 weeks. The SD rats were allowed to recover for 4 weeks after withdrawal. We evaluated the physiological condition of the rats, including their ophthalmological condition, body weight, food intake, body temperature, blood biochemistry, urine, neutralizing antibody, inflammation at the injection site, and organs weight. In summary, no dose-dependent adverse toxicological changes were observed, and a recovery trend was obvious, which proved the preclinical safety of the candidate omicron vaccine and provided evidence for clinical trials in humans.
ABSTRACT
Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in late 2019, the virus has been mutating continuously, resulting in the continuous emergence of variants and creating challenges for epidemic prevention and control. Here, we immunized mice with different vaccine candidates, revealing the immune, protein, and metabolomic changes that take place in vaccines composed of different variants. We found that the prototype strain and Delta- and Omicron-variant inactivated vaccine candidates could all induce a high level of neutralizing antibodies and cellular immunity responses in mice. Next, we found that the metabolic and protein profiles were changed, showing a positive association with immune responses, and the level of the change was distinct in different inactivated vaccines, indicating that amino acid variations could affect metabolomics and proteomics. Our findings reveal differences between vaccines at the metabolomic and proteomic levels. These insights provide a novel direction for the immune evaluation of vaccines and could be used to guide novel strategies for vaccine design.
Subject(s)
COVID-19 , Viral Vaccines , Amino Acids , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Immunity , Mice , Proteomics , SARS-CoV-2 , Vaccines, InactivatedABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused huge social and economic distress. Given its rapid spread and the lack of specific treatment options, SARS-CoV-2 needs to be inactivated according to strict biosafety measures during laboratory diagnostics and vaccine development. The inactivation method for SARS-CoV-2 affects research related to the natural virus and its immune activity as an antigen in vaccines. In this study, we used size exclusion chromatography, western blotting, ELISA, an electron microscope, dynamic light scattering, circular dichroism, and surface plasmon resonance to evaluate the effects of four different chemical inactivation methods on the physical and biochemical characterization of SARS-CoV-2. Formaldehyde and ß-propiolactone (BPL) treatment can completely inactivate the virus and have no significant effects on the morphology of the virus. None of the four tested inactivation methods affected the secondary structure of the virus, including the α-helix, antiparallel ß-sheet, parallel ß-sheet, ß-turn, and random coil. However, formaldehyde and long-term BPL treatment (48 h) resulted in decreased viral S protein content and increased viral particle aggregation, respectively. The BPL treatment for 24 h can completely inactivate SARS-CoV-2 with the maximum retention of the morphology, physical properties, and the biochemical properties of the potential antigens of the virus. In summary, we have established a characterization system for the comprehensive evaluation of virus inactivation technology, which has important guiding significance for the development of vaccines against SARS-CoV-2 variants and research on natural SARS-CoV-2.