Journal: Scientific Reports

Article Title: Immunogenicity and protection efficacy of a COVID-19 DNA vaccine encoding spike protein with D614G mutation and optimization of large-scale DNA vaccine production

doi: 10.1038/s41598-024-64690-5

Figure Lengend Snippet: In silico analyses of vaccine antigen. ( A ) Variations detected in Spike gene of 20 SARS-CoV-2 isolates collected from various provinces of Türkiye. The map in figure was generated by Microsoft 365 Excel. ( B ) A1841G mutation causes D614G amino acid alteration ( C ) 3D image of human ACE2 receptor docked with Wuhan Spike protein and coSpikeD614G vaccine antigen. Purple color: Spike protein; blue color: receptor binding domain (RBD) of Spike protein; green color: human ACE2 receptor; red color: receptor binding motif of human ACE2 protein.

Article Snippet: Neutralizing antibody responses in vaccinated mice sera were analyzed using an ELISA-based SARS-CoV-2 surrogate Virus Neutralization Test (sVNT) which is a S1 protein/ACE2 ligand binding assay) (AffinityImmuno, Canada) according to the manufacturer’s protocol.

Techniques: In Silico, Generated, Mutagenesis, Binding Assay

Journal: Scientific Reports

Article Title: Immunogenicity and protection efficacy of a COVID-19 DNA vaccine encoding spike protein with D614G mutation and optimization of large-scale DNA vaccine production

doi: 10.1038/s41598-024-64690-5

Figure Lengend Snippet: Animal studies and humoral immune response elicited by pcoSpikeD614G DNA vaccine. ( A ) Brief timeline of animal studies. BALB/c mice were immunized to assess the immunogenicity and K18-hACE2 transgenic mice were immunized to determine protective efficacy conferred by pcoSpikeD614G DNA vaccine ( B ) Western blot image shows the presence of anti-S1 and anti S1 + S2 antibody responses in sera of vaccinated BALB/c mice. Lane 1: Protein ladder; Lanes 2 and 3: recombinant S1 protein probed with pooled pcoSpikeD614G vaccinated mice sera immunized thrice through ID + EP and IM routes. Red arrowheads show the recombinant S1 proteins with a size of over \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sim$$\end{document} ∼ 76.41 kDa due to glycosylation; Lanes 4 and 5: recombinant S1 + S2 protein pooled with pcoSpikeD614G vaccinated mice sera immunized thrice through ID + EP and IM routes. Blue arrowheads show the recombinant S1 + S2 proteins with a size of over \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sim$$\end{document} ∼ 138.5 kDa due to glycosylation; Lane 6–7 and 8–9: recombinant S1 and S1 + S2 proteins probed with pooled vaccinated mice sera administered with empty pVAX1. Original Western blot images have been shown in Supplementary file named S5 Figure ( C ) The anti-S1 IgG kinetics derived from mice immunized with pcoSpikeD614G administered through ID + EP and IM routes show significant increase at day 70 compared to controls ( D ) IgG2a/IgG1 polarization was assessed at days 0 and 70 for empty pVAX1 and pcoSpikeD614G and IgG2a responses were significantly higher ( E ) The ratio of IgG2a/IgG1 is slightly higher in pcoSpikeD614G administered through IM route ( F ) SARS-CoV-2 Surrogate Virus Neutralization Test showed that inhibition potential of 1:10 diluted sera obtained from vaccinated mice at day 70 was significantly higher than controls ( G ) SARS-CoV-2 50% neutralization titers (VNT50) in sera of in pcoSpikeD614G immunized mice collated on day 70. Data are presented as GMT ± SD.

Article Snippet: Neutralizing antibody responses in vaccinated mice sera were analyzed using an ELISA-based SARS-CoV-2 surrogate Virus Neutralization Test (sVNT) which is a S1 protein/ACE2 ligand binding assay) (AffinityImmuno, Canada) according to the manufacturer’s protocol.

Techniques: Transgenic Assay, Western Blot, Recombinant, Derivative Assay, Virus, Neutralization, Inhibition

Journal: Scientific Reports

Article Title: Immunogenicity and protection efficacy of a COVID-19 DNA vaccine encoding spike protein with D614G mutation and optimization of large-scale DNA vaccine production

doi: 10.1038/s41598-024-64690-5

Figure Lengend Snippet: Protection conferred by pcoSpikeD614G DNA vaccine in K18-hACE2 transgenic mice challenged by SARS-CoV-2. ( A ) Gross pathological scoring of lungs to evaluate the level of pneumonia. Healthy lungs were scored as 0, edema-hyperemia between 0.5 and 1, pneumonia lesions were between 1.5 and 5 and dead mice were scored as 5. ( B ) Mean Ct values of RT-qPCR targeting NC gene of SARS‐CoV‐2 derived from the lungs of mice. The virus load is represented by Crossing point threshold (Ct) values. The Ct value of a negative PCR sample is accepted as 40 ( C ) Histopathology scoring of lungs to evaluate the level of inflammation status. Absence of inflammation is represented by 0 and various level of inflammation were scored between 1 and 3. Three lungs from the control group and one lung from the mice group immunized with pcoSpikeD614G administered through IM route were not scored ( D, E ) In the group of mice immunized with pcoSpikeD614G administered through IM route, images show normal lungs at magnifications of 4 × and 10 × . Arrow shows alveoli with normal morphology ( F, G ) In the group of mice immunized with pcoSpikeD614G administered through ID + EP route, images show normal lungs at magnifications of 4 × and 10 × . Arrow shows alveoli with normal morphology. ( H, I ) In the control group of mice, images show lungs with interstitial inflammatory cell infiltration at magnifications of 4 × and 10 × . Asterisks indicate areas of lymphocyte infiltration in the interalveolar spaces. ( J ) Kaplan–Meier Survival analysis after intranasal instillation of 10 5 TCID 50 virus for 3 consecutive days.

Article Snippet: Neutralizing antibody responses in vaccinated mice sera were analyzed using an ELISA-based SARS-CoV-2 surrogate Virus Neutralization Test (sVNT) which is a S1 protein/ACE2 ligand binding assay) (AffinityImmuno, Canada) according to the manufacturer’s protocol.

Techniques: Transgenic Assay, Quantitative RT-PCR, Derivative Assay, Virus, Histopathology

Journal: Vaccine

Article Title: Immunogenicity of heterologous inactivated and adenoviral-vectored COVID-19 vaccine: Real-world data

doi: 10.1016/j.vaccine.2022.04.043

Figure Lengend Snippet: Anti-RBD IgG and neutralizing capacity measured by a surrogate virus neutralization test (sVNT) against SARS-CoV-2 original Wuhan strain following heterologous CoronaVac/AZD1222 and homologous CoronaVac or AZD1222 vaccination. (A) anti-RBD IgG obtained at 28 days after homologous CoronaVac/CoronaVac (red), 14–75 days after CoronaVac/AZD1222 (green), and 28 days after homologous AZD1222/AZD1222 (blue). (B) Percentage of inhibition against Wuhan strain was tested using a commercially available test kit (Euroimmun, Lubeck, Germany). Lines indicate geometric mean titers and 95% confidence intervals for anti-RBD IgG and median with interquartile range for sVNT. Dotted lines indicate the manufacturer’s pre-specified threshold for seropositivity. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

Article Snippet: Anti-RBD IgG and neutralizing capacity measured by a surrogate virus neutralization test (sVNT) against SARS-CoV-2 original Wuhan strain following heterologous CoronaVac/AZD1222 and homologous CoronaVac or AZD1222 vaccination. (A) anti-RBD IgG obtained at 28 days after homologous CoronaVac/CoronaVac (red), 14–75 days after CoronaVac/AZD1222 (green), and 28 days after homologous AZD1222/AZD1222 (blue). (B) Percentage of inhibition against Wuhan strain was tested using a commercially available test kit (Euroimmun, Lubeck, Germany).

Techniques: Neutralization, Inhibition

Journal: Vaccine

Article Title: Immunogenicity of heterologous inactivated and adenoviral-vectored COVID-19 vaccine: Real-world data

doi: 10.1016/j.vaccine.2022.04.043

Figure Lengend Snippet: Neutralizing capacity measured by a surrogate virus neutralization test (sVNT) against SARS-CoV-2 wild-type and variants following heterologous CoronaVac/AZD1222 and homologous CoronaVac or AZD1222 vaccination. Percentage of inhibition against SARS-CoV-2 (A) Wild type (rhombus), (B) B.1.1.7 (circle), (C) B.1.351 (square) and (D) B.1.617.2 (triangle) was measured using cPass TM (GenScript, Jiangsu, China). Bars indicate median. Lines indicate the interquartile range. Dotted lines indicate the manufacturer’s pre-specified threshold for seropositivity.

Article Snippet: Anti-RBD IgG and neutralizing capacity measured by a surrogate virus neutralization test (sVNT) against SARS-CoV-2 original Wuhan strain following heterologous CoronaVac/AZD1222 and homologous CoronaVac or AZD1222 vaccination. (A) anti-RBD IgG obtained at 28 days after homologous CoronaVac/CoronaVac (red), 14–75 days after CoronaVac/AZD1222 (green), and 28 days after homologous AZD1222/AZD1222 (blue). (B) Percentage of inhibition against Wuhan strain was tested using a commercially available test kit (Euroimmun, Lubeck, Germany).

Techniques: Neutralization, Inhibition

Journal: Vaccine

Article Title: Immunogenicity of heterologous inactivated and adenoviral-vectored COVID-19 vaccine: Real-world data

doi: 10.1016/j.vaccine.2022.04.043

Figure Lengend Snippet: Comparison between neutralizing capacity measured by a surrogate virus neutralization test (sVNT) against variants relative to the wild type in sera samples obtained from (A) homologous CoronaVac/CoronaVac, (B) heterologous CoronaVac/AZD1222, and (C) homologous AZD1222/AZD1222 vaccinees. Lines indicate the median of percent inhibition. Dotted lines indicate the manufacturer’s pre-specified threshold for seropositivity.

Article Snippet: Anti-RBD IgG and neutralizing capacity measured by a surrogate virus neutralization test (sVNT) against SARS-CoV-2 original Wuhan strain following heterologous CoronaVac/AZD1222 and homologous CoronaVac or AZD1222 vaccination. (A) anti-RBD IgG obtained at 28 days after homologous CoronaVac/CoronaVac (red), 14–75 days after CoronaVac/AZD1222 (green), and 28 days after homologous AZD1222/AZD1222 (blue). (B) Percentage of inhibition against Wuhan strain was tested using a commercially available test kit (Euroimmun, Lubeck, Germany).

Techniques: Neutralization, Inhibition