RESUMEN
Severe acute respiratory syndrome coronavirus 2 had devastating consequences for human health. Despite the introduction of several vaccines, COVID-19 continues to pose a serious health risk due to emerging variants of concern. DNA vaccines gained importance during the pandemic due to their advantages such as induction of both arms of immune response, rapid development, stability, and safety profiles. Here, we report the immunogenicity and protective efficacy of a DNA vaccine encoding spike protein with D614G mutation (named pcoSpikeD614G) and define a large-scale production process. According to the in vitro studies, pcoSpikeD614G expressed abundant spike protein in HEK293T cells. After the administration of pcoSpikeD614G to BALB/c mice through intramuscular (IM) route and intradermal route using an electroporation device (ID + EP), it induced high level of anti-S1 IgG and neutralizing antibodies (P < 0.0001), strong Th1-biased immune response as shown by IgG2a polarization (P < 0.01), increase in IFN-γ levels (P < 0.01), and increment in the ratio of IFN-γ secreting CD4+ (3.78-10.19%) and CD8+ (5.24-12.51%) T cells. Challenging K18-hACE2 transgenic mice showed that pcoSpikeD614G administered through IM and ID + EP routes conferred 90-100% protection and there was no sign of pneumonia. Subsequently, pcoSpikeD614G was evaluated as a promising DNA vaccine candidate and scale-up studies were performed. Accordingly, a large-scale production process was described, including a 36 h fermentation process of E. coli DH5α cells containing pcoSpikeD614G resulting in a wet cell weight of 242 g/L and a three-step chromatography for purification of the pcoSpikeD614G DNA vaccine.
Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Ratones Endogámicos BALB C , Mutación , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Vacunas de ADN , Vacunas de ADN/inmunología , Vacunas de ADN/administración & dosificación , Vacunas de ADN/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Animales , Humanos , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Ratones , COVID-19/prevención & control , COVID-19/inmunología , Células HEK293 , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Femenino , Inmunogenicidad Vacunal , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunologíaRESUMEN
C-Vx is a bioprotective product designed to boost the immune system. This study aimed to determine the antiviral activity of the C-Vx substance against SARS-CoV-2 infection. The effect of C-Vx in K18-hACE2 transgenic mice against the SARS-CoV-2 virus was investigated. For this purpose, ten mice were separated into experimental and control groups. Animals were infected with SARS-CoV-2 prior to the administration of the product to determine whether the product has a therapeutic effect similar to that demonstrated in previous human studies, at a histopathological and molecular level. C-Vx-treated mice survived the challenge, whereas the control mice became ill and/or died. The cytokine-chemokine panel with blood samples taken during the critical days of the disease revealed detailed immune responses. Our findings showed that C-Vx presented 90% protection against the SARS-CoV-2 virus-infected mice. The challenge results and cytokine responses of K18-hACE2 transgenic mice matched previous scientific studies, demonstrating the C-Vx's antiviral efficiency.
Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Ratones , Animales , Ratones Transgénicos , Antivirales/farmacología , Antivirales/uso terapéutico , Citocinas , Modelos Animales de EnfermedadRESUMEN
SCOPE: The purpose of this study was to look into the antiviral activity of a plant extract derived from the roots of the Saussurea lappa as a food supplement against SARS-CoV-2 infection. METHODS AND RESULTS: Vero E6 cells are employed in the study to test the neutralizing effect of Saussurea lappa extract against the SARS-CoV-2 virus. For anti-viral activity detection, a sensitive real-time cell analyzer (xCELLigence RTCA) with a high repetition rate is used. A challenge experiment in mice is planned as a result of the in vitro analysis. A challenge test against SARS-CoV-2 is performed with 10 adult female K18-hACE2 transgenic mice in each group for this purpose. The mice in the S. lappa Group are gavaged 2 days before the virus is administered intranasally (i.n.). The control group received PBS instead of the extract. SARS-CoV-2 virus is administered i.n. under anesthesia for the first 3 days of the experiment, and S. lappa extract was administered by gavage in the afternoon. On the 10th day, mice in the S. lappa group survived the study, whereas animals in the control group grew ill and/or died. In this study, the extract protects the mice against the SARS-CoV-2 virus in 90% of the cases. CONCLUSIONS: This study demonstrates that the Saussurea plant has antiviral effects against SARS-CoV-2 in vitro and in animal models.