Safety and Immunogenicity Evaluation of Inactivated whole-virus-SARS-COV-2 As Emerging Vaccine Development In Egypt

AbstractThe current worldwide pandemic COVID-19 is causing severe human health problems, with high numbers of mortality rates and huge economic burdens that require an urgent demand for safe, and effective and vaccine development. Our study was the first trail to development and evaluation of safety and immune response to inactivated whole SARS-COV-2 virus vaccine adjuvanted with aluminium hydroxide. We used characterized SARS-COV-2 strain, severe acute respiratory syndrome coronavirus 2 isolates (SARS-CoV-2/human/EGY/Egy-SERVAC/2020) with accession numbers; MT981440; MT981439; MT981441; MT974071; MT974069 and MW250352 at GenBank that isolated from Egyptian patients SARS-CoV-2-positive. Development of the vaccine was carried out in a BSL - 3 facilities and the immunogenicity was determined in mice at two doses (55µg and 100µg per dose). All vaccinated mice were received a booster dose 14 days post first immunization. Our results demonstrated distinct cytopathic effect on the vero cell monolayers induced through SARS-COV-2 propagation and the viral particles were identified as Coronaviridae by transmission electron microscopy. SARS-CoV-2 was identified by RT-PCR performed on the cell culture. Immunogenicity of the developed vaccine indicated the high antigen-binding and neutralizing antibody titers, regardless the dose concentration, with excellent safety profiles.However, no deaths or clinical symptoms in mice groups. The efficacy of the inactivated vaccine formulation was tested by wild virus challenge the vaccinated mice and detection of viral replication in lung tissues. Vaccinated mice recorded complete protection from challenge infection three weeks post second dose. SARS-COV-2 replication was not observed in the lungs of mice following SARS-CoV-2 challenge, regardless of the level of serum neutralizing antibodies. This finding will support the future trials for evaluation an applicable SARS-CoV-2 vaccine candidate.

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Safety and immunogenicity evaluation of inactivated whole-virus-SARS-COV-2 as emerging vaccine development in Egypt

Antibody Therapeutics ◽

10.1093/abt/tbab012 ◽

2021 ◽

Author(s):

Amani A Saleh ◽

Mohamed A Saad ◽

Islam Ryan ◽

Magdy Amin ◽

Mohamed I Shindy ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Vaccine Development ◽

Clinical Symptoms ◽

Neutralizing Antibody ◽

Positive Development ◽

Effective Vaccine ◽

Inactivated Vaccine ◽

Virus Challenge ◽

Transmission Electron ◽

Dose Concentration

Abstract Background Current worldwide pandemic COVID-19 with high numbers of mortality rates and huge economic problems require an urgent demand for safe and effective vaccine development. Inactivated SARS-CoV2 vaccine with alum. Hydroxide can play an important role in reducing the impacts of the COVID-19 pandemic. In this study, vaccine efficacy was evaluated through the detection of the neutralizing antibodies that protect mice from challenge with SARS-CoV 2 three weeks after the 2nd dose. We conclude that the vaccine described here has safety and desirable properties, and our data support further development and plans for clinical trials. Methods Characterized SARS-COV-2 strain, severe acute respiratory syndrome coronavirus 2 isolates (SARS-CoV-2/human/EGY/Egy-SERVAC/2020) with accession numbers; MT981440; MT981439; MT981441; MT974071; MT974069, and MW250352 at GenBank were isolated from Egyptian patients SARS-CoV-2-positive. Development of inactivated vaccine was carried out in a BSL—3 facilities and the immunogenicity was determined in mice at two doses (55 μg and 100 μg per dose). Results The distinct cytopathic effect (CPE) induced by SARS-COV-2 propagation on Vero cell monolayers and the viral particles were identified as Coronaviridae by transmission electron microscopy and RT-PCR on infected cells cultures. Immunogenicity of the developed vaccine indicated the high antigen-binding and neutralizing antibody titers, regardless of the dose concentration, with excellent safety profiles and no deaths or clinical symptoms in mice groups. The efficacy of the inactivated vaccine formulation was tested by the wild virus challenge of the vaccinated mice and viral replication detection in lung tissues. Conclusions Vaccinated mice recorded complete protection from challenge infection via inhibition of SARS-COV-2 replication in the lung tissues of mice following virus challenge, regardless of the level of serum neutralizing antibodies. This finding will support future trials for the evaluation of an applicable SARS-CoV-2 vaccine candidate.

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Antibody titers measured by commercial assays are correlated with neutralizing antibody titers calibrated by international standards

10.1101/2021.07.16.21260618 ◽

2021 ◽

Author(s):

Yu-An Kung ◽

Chung-Guei Huang ◽

Sheng-Yu Huang ◽

Kuan-Ting Liu ◽

Peng-Nien Huang ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Vaccine Development ◽

Geometric Mean ◽

Neutralizing Antibody ◽

Diagnostic Techniques ◽

International Standards ◽

World Health ◽

Serum Samples ◽

Antibody Titers ◽

Health Organization

The World Health Organization (WHO) has highlighted the importance of an international standard (IS) for SARS-CoV-2 neutralizing antibody titer detection, with the aim of calibrating different diagnostic techniques. In this study, IS was applied to calibrate neutralizing antibody titers (IU/mL) and binding antibody titers (BAU/mL) in response to SARS-CoV-2 vaccines. Serum samples were collected from participants receiving the Moderna (n = 20) and Pfizer (n = 20) vaccines at three time points: pre-vaccination, after one dose, and after two doses. We obtained geometric mean titers of 1404.16 and 928.75 IU/mL for neutralizing antibodies after two doses of the Moderna and Pfizer vaccines, respectively. These values provide an important baseline for vaccine development and the implementation of non-inferiority trials. We also compared three commercially available kits from Roche, Abbott, and MeDiPro for the detection of COVID-19 antibodies based on binding affinity to S1 and/or RBD. Our results demonstrated that antibody titers measured by commercial assays are highly correlated with neutralizing antibody titers calibrated by IS.

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Prevalence and Persistence of Maternal Dengue Neutralizing Antibodies in Infants From Central and Southern Thailand: A Retrospective Cohort Study

Asia Pacific Journal of Public Health ◽

10.1177/1010539519853396 ◽

2019 ◽

Vol 31 (4) ◽

pp. 288-295 ◽

Cited By ~ 1

Author(s):

Adrienne Guignard ◽

François Haguinet ◽

Stéphanie Wéry ◽

Phirangkul Kerdpanich

Keyword(s):

Neutralizing Antibodies ◽

Vaccine Development ◽

Geometric Mean ◽

Neutralizing Antibody ◽

Maternal Antibodies ◽

Childhood Immunization ◽

Serum Samples ◽

Denv Serotypes ◽

Antibody Titers ◽

Antibody Kinetics

Understanding maternal dengue virus (DENV) neutralizing antibody kinetics in infants remains timely to develop a safe and effective childhood immunization. This retrospective study evaluated the prevalence and persistence of maternal antibody titers against DENV serotypes 1 to 4 in 139 Thai infants at 2, 6, and 7 months of age, using serum samples collected in a vaccination trial ( http://clinicaltrials.gov ; NCT00197275). Neutralizing antibodies against all 4 DENV serotypes were detected in 87.8% and 22.9% of infants at 2 and 7 months, respectively. At 2 months, DENV-4 neutralizing antibody geometric mean titers were notably lower (80) compared with DENV-1 to DENV-3 (277-471). Our results corroborate previous findings that DENV-1 to DENV-4 maternal antibodies persist at 7 months despite titers decrease from 2 months onwards. As persisting maternal antibodies may inhibit immune responses in DENV-vaccinated infants, a comprehensive understanding of DENV antibody kinetics is required in the perspective of vaccine development for infants.

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SARS-CoV-2 ferritin nanoparticle vaccines elicit broad SARS coronavirus immunogenicity

10.1101/2021.05.09.443331 ◽

2021 ◽

Author(s):

M. Gordon Joyce ◽

Kayvon Modjarrad

Keyword(s):

Neutralizing Antibodies ◽

Vaccine Development ◽

Design Strategies ◽

Virus Challenge ◽

High Magnitude ◽

Antigenic Properties ◽

Blocking Activity ◽

Antibody Titers ◽

Engineered Nanoparticle

The need for SARS-CoV-2 next-generation vaccines has been highlighted by the rise of variants of concern (VoC) and the long-term threat of other coronaviruses. Here, we designed and characterized four categories of engineered nanoparticle immunogens that recapitulate the structural and antigenic properties of prefusion Spike (S), S1 and RBD. These immunogens induced robust S-binding, ACE2-inhibition, and authentic and pseudovirus neutralizing antibodies against SARS-CoV-2 in mice. A Spike-ferritin nanoparticle (SpFN) vaccine elicited neutralizing titers more than 20-fold higher than convalescent donor serum, following a single immunization, while RBD-Ferritin nanoparticle (RFN) immunogens elicited similar responses after two immunizations. Passive transfer of IgG purified from SpFN- or RFN-immunized mice protected K18-hACE2 transgenic mice from a lethal SARS-CoV-2 virus challenge. Furthermore, SpFN- and RFN-immunization elicited ACE2 blocking activity and neutralizing ID50 antibody titers >2,000 against SARS-CoV-1, along with high magnitude neutralizing titers against major VoC. These results provide design strategies for pan-coronavirus vaccine development.

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The feasibility of convalescent plasma therapy in severe COVID- 19 patients: a pilot study

10.1101/2020.03.16.20036145 ◽

2020 ◽

Cited By ~ 18

Author(s):

Kai Duan ◽

Bende Liu ◽

Cesheng Li ◽

Huajun Zhang ◽

Ting Yu ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Clinical Symptoms ◽

Antiviral Agents ◽

Neutralizing Antibody ◽

Optimal Dose ◽

Plasma Therapy ◽

Reactive Protein ◽

Antibody Titers ◽

Novel Coronavirus ◽

High Level

AbstractCurrently, there are no approved specific antiviral agents for 2019 novel coronavirus disease (COVID-19). In this study, ten severe patients confirmed by real-time viral RNA test were enrolled prospectively. One dose of 200 mL convalescent plasma (CP) derived from recently recovered donors with the neutralizing antibody titers above 1:640 was transfused to the patients as an addition to maximal supportive care and antiviral agents. The primary endpoint was the safety of CP transfusion. The second endpoints were the improvement of clinical symptoms and laboratory parameters within 3 days after CP transfusion. The median time from onset of illness to CP transfusion was 16.5 days. After CP transfusion, the level of neutralizing antibody increased rapidly up to 1:640 in five cases, while that of the other four cases maintained at a high level (1:640). The clinical symptoms were significantly improved along with increase of oxyhemoglobin saturation within 3 days. Several parameters tended to improve as compared to pre-transfusion, including increased lymphocyte counts (0.65×109/L vs. 0.76×109/L) and decreased C-reactive protein (55.98 mg/L vs. 18.13 mg/L). Radiological examinations showed varying degrees of absorption of lung lesionswithin 7 days. The viral load was undetectable after transfusion in seven patients who had previous viremia. No severe adverse effects were observed. This study showed CP therapy was welltolerated and could potentially improve the clinical outcomes through neutralizing viremia in severe COVID-19 cases. The optimal dose and time point, as well as the clinical benefit of CP therapy, needs further investigation in larger well-controlled trials.Significance StatementCOVID-19 is currently a big threat to global health. However, no specific antiviral agents are available for its treatment. In this work, we explored the feasibility of convalescent plasma (CP) transfusion to rescue severe patients. The results from 10 severe adult cases showed that one dose (200 mL) of CP was welltolerated and could significantly increase or maintain the neutralizing antibodies at a high level, leading to disappearance of viremia in 7 days. Meanwhile, clinical symptoms and paraclinical criteria rapidly improved within 3 days. Radiological examination showed varying degrees of absorption of lung lesions within 7 days. These results indicate that CP can serve as a promising rescue option for severe COVID-19 while the randomized trial is warranted.

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Pathogenicity of Seneca Valley virus in pigs and detection in Culicoides from an infected pig farm

Virology Journal ◽

10.1186/s12985-021-01679-w ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Jinyong Zhang ◽

Chenghui Li ◽

Yuan Meng ◽

Yubiao Xie ◽

Ning Shi ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Clinical Symptoms ◽

Neutralizing Antibody ◽

Antibody Titers ◽

Pig Farm ◽

Seneca Valley Virus ◽

Set Up ◽

Almost All ◽

And Control ◽

Virus Distribution

Abstract Background Porcine vesicular disease is caused by the Seneca Valley virus (SVV), it is a novel Picornaviridae, which is prevalent in several countries. However, the pathogenicity of SVV on 5–6 week old pigs and the transmission routes of SVV remain unknown. Methods This research mainly focuses on the pathogenicity of the CH-GX-01-2019 strain and the possible vector of SVV. In this study, 5–6 week old pigs infected with SVV (CH-GX-01-2019) and its clinical symptoms (including rectal temperatures and other clinical symptoms) were monitored, qRT-PCR were used to detect the viremia and virus distribution. Neutralization antibody assay was set up during this research. Mosquitoes and Culicoides were collected from pigsties after pigs challenge with SVV, and SVV detection within mosquitoes and Culicoides was done via RT-PCR. Results The challenged pigs presented with low fevers and mild lethargy on 5–8 days post infection. The viremia lasted more than 14 days. SVV was detected in almost all tissues on the 14th day following the challenge, and it was significantly higher in the hoofs (vesicles) and lymph nodes in comparison with other tissues. Neutralizing antibodies were also detected and could persist for more than 28 days, in addition neutralizing antibody titers ranged from 1:128 to 1:512. Mosquitoes and Culicoides were collected from the pigsty environments following SVV infection. Although SVV was not detected in the mosquitoes, it was present in the Culicoides, however SVV could not be isolated from the positive Culicoides. Conclusions Our work has enriched the knowledge relating to SVV pathogenicity and possible transmission routes, which may lay the foundation for further research into the prevention and control of this virus.

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Application of an Endothelial Cell Culture Assay for the Detection of Neutralizing Anti-Clostridium Perfringens Beta-Toxin Antibodies in a Porcine Vaccination Trial

Toxins ◽

10.3390/toxins11040225 ◽

2019 ◽

Vol 11 (4) ◽

pp. 225 ◽

Cited By ~ 2

Author(s):

Olivia K. Richard ◽

Sven Springer ◽

Jacqueline Finzel ◽

Tobias Theuß ◽

Marianne Wyder ◽

...

Keyword(s):

Endothelial Cells ◽

Clostridium Perfringens ◽

Neutralizing Antibodies ◽

Vaccine Development ◽

Neutralizing Antibody ◽

Antibody Activity ◽

Antibody Titers ◽

Type C ◽

Cell Culture Assay ◽

Beta Toxin

Background: Beta-toxin (CPB) is the major virulence factor of Clostridium perfringens type C, causing hemorrhagic enteritis in newborn pigs but also other animals and humans. Vaccines containing inactivated CPB are known to induce protective antibody titers in sow colostrum and neutralization of the CPB activity is thought to be essential for protective immunity in newborn piglets. However, no method is available to quantify the neutralizing effect of vaccine-induced antibody titers in pigs. (2) Methods: We developed a novel assay for the quantification of neutralizing anti-CPB antibodies. Sera and colostrum of sows immunized with a commercial C. perfringens type A and C vaccine was used to determine neutralizing effects on CPB induced cytotoxicity in endothelial cells. Antibody titers of sows and their piglets were determined and compared to results obtained by an ELISA. (3) Results: Vaccinated sows developed neutralizing antibodies against CPB in serum and colostrum. Multiparous sows developed higher serum and colostrum antibody titers after booster vaccinations than uniparous sows. The antibody titers of sows and those of their piglets correlated highly. Piglets from vaccinated sows were protected against intraperitoneal challenge with C. perfringens type C supernatant. (4) Conclusions: The test based on primary porcine endothelial cells quantifies neutralizing antibody activity in serum and colostrum of vaccinated sows and could be used to reduce and refine animal experimentation during vaccine development.

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Pathogenicity of Seneca Valley virus in Pigs and Detection in Culicoides from an Infected Pig Farm

10.21203/rs.3.rs-392318/v1 ◽

2021 ◽

Author(s):

Jinyong Zhang ◽

Chenghui Li ◽

Yuan Meng ◽

Yubiao Xie ◽

Ning Shi ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Clinical Symptoms ◽

Neutralizing Antibody ◽

Antibody Titers ◽

Pig Farm ◽

Seneca Valley Virus ◽

Set Up ◽

Almost All ◽

And Control ◽

Virus Distribution

Abstract Background: Porcine vesicular disease is caused by the Seneca Valley virus (SVV), it is a novel Picornaviridae, which is prevalent in several countries. However, the pathogenicity of SVV on 5-6 week old pigs and the transmission routes of SVV remain unknown.Methods: This research mainly focuses on the pathogenicity of the CH-GX-01-2019 strain and the possible vector of SVV. In this study, 5-6 week old pigs infected with SVV (CH-GX-01-2019) and its clinical symptoms (including rectal temperatures and other clinical symptoms) were monitored, qRT-PCR were used to detect the viremia and virus distribution. Neutralization antibody assay was set up during this research. Mosquitoes and Culicoides were collected from pigsties after pigs challenge with SVV, and SVV detection within mosquitoes and Culicoides was done via RT-PCR.Results: The challenged pigs presented with low fevers and mild lethargy on 5-8 days post infection (dpi). The viremia lasted more than 14 days. SVV was detected in almost all tissues on the 14th day following the challenge, and it was significantly higher in the hoofs (vesicles) and lymph nodes in comparison with other tissues. Neutralizing antibodies were also detected and could persist for more than 28 days, in addition neutralizing antibody titers ranged from 1:128 to 1:512. Mosquitoes and Culicoides were collected from the pigsty environments following SVV infection. Although SVV was not detected in the mosquitoes, it was present in the Culicoides, however SVV could not be isolated from the positive Culicoides. Conclusions: Our work has enriched the knowledge relating to SVV pathogenicity and possible transmission routes, which may lay the foundation for further research into the prevention and control of this virus.

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Dengue 2 PDK-53 Virus as a Chimeric Carrier for Tetravalent Dengue Vaccine Development

Journal of Virology ◽

10.1128/jvi.77.21.11436-11447.2003 ◽

2003 ◽

Vol 77 (21) ◽

pp. 11436-11447 ◽

Cited By ~ 128

Author(s):

Claire Y.-H. Huang ◽

Siritorn Butrapet ◽

Kiyotaka R. Tsuchiya ◽

Natth Bhamarapravati ◽

Duane J. Gubler ◽

...

Keyword(s):

Vaccine Development ◽

Neutralizing Antibody ◽

Vero Cells ◽

Vaccine Virus ◽

Wild Type ◽

Dengue Vaccine ◽

Virus Challenge ◽

Viral Interference ◽

Antibody Titers ◽

Virus Expression

ABSTRACT Attenuation markers of the candidate dengue 2 (D2) PDK-53 vaccine virus are encoded by mutations that reside outside of the structural gene region of the genome. We engineered nine dengue virus chimeras containing the premembrane (prM) and envelope (E) genes of wild-type D1 16007, D3 16562, or D4 1036 virus within the genetic backgrounds of wild-type D2 16681 virus and the two genetic variants (PDK53-E and PDK53-V) of the D2 PDK-53 vaccine virus. Expression of the heterologous prM-E genes in the genetic backgrounds of the two D2 PDK-53 variants, but not that of wild-type D2 16681 virus, resulted in chimeric viruses that retained PDK-53 characteristic phenotypic markers of attenuation, including small plaque size and temperature sensitivity in LLC-MK2 cells, limited replication in C6/36 cells, and lack of neurovirulence in newborn ICR mice. Chimeric D2/1, D2/3, and D2/4 viruses replicated efficiently in Vero cells and were immunogenic in AG129 mice. Chimeric D2/1 viruses protected adult AG129 mice against lethal D1 virus challenge. Two tetravalent virus formulations, comprised of either PDK53-E- or PDK53-V-vectored viruses, elicited neutralizing antibody titers in mice against all four dengue serotypes. These antibody titers were similar to the titers elicited by monovalent immunizations, suggesting that viral interference did not occur in recipients of the tetravalent formulations. The results of this study demonstrate that the unique attenuation loci of D2 PDK-53 virus make it an attractive vector for the development of live attenuated flavivirus vaccines.

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A longitudinal study of SARS-CoV-2-infected patients reveals a high correlation between neutralizing antibodies and COVID-19 severity

Cellular and Molecular Immunology ◽

10.1038/s41423-020-00588-2 ◽

2021 ◽

Author(s):

Vincent Legros ◽

Solène Denolly ◽

Manon Vogrig ◽

Bertrand Boson ◽

Eglantine Siret ◽

...

Keyword(s):

Intensive Care ◽

Neutralizing Antibodies ◽

Vaccine Development ◽

Surface Protein ◽

Humoral Response ◽

Neutralizing Antibody ◽

Rapid Decline ◽

Serum Samples ◽

Immune Correlates ◽

Human Coronaviruses

AbstractUnderstanding the immune responses elicited by SARS-CoV-2 infection is critical in terms of protection against reinfection and, thus, for public health policy and vaccine development for COVID-19. In this study, using either live SARS-CoV-2 particles or retroviruses pseudotyped with the SARS-CoV-2 S viral surface protein (Spike), we studied the neutralizing antibody (nAb) response in serum samples from a cohort of 140 SARS-CoV-2 qPCR-confirmed infections, including patients with mild symptoms and also more severe forms, including those that required intensive care. We show that nAb titers correlated strongly with disease severity and with anti-spike IgG levels. Indeed, patients from intensive care units exhibited high nAb titers; conversely, patients with milder disease symptoms had heterogeneous nAb titers, and asymptomatic or exclusive outpatient-care patients had no or low nAbs. We found that nAb activity in SARS-CoV-2-infected patients displayed a relatively rapid decline after recovery compared to individuals infected with other coronaviruses. Moreover, we found an absence of cross-neutralization between endemic coronaviruses and SARS-CoV-2, indicating that previous infection by human coronaviruses may not generate protective nAbs against SARS-CoV-2. Finally, we found that the D614G mutation in the spike protein, which has recently been identified as the current major variant in Europe, does not allow neutralization escape. Altogether, our results contribute to our understanding of the immune correlates of SARS-CoV-2-induced disease, and rapid evaluation of the role of the humoral response in the pathogenesis of SARS-CoV-2 is warranted.

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