scholarly journals Broad and Long-lasting Immune Response against SARS-CoV-2 Omicron and Other Variants by PIKA-Adjuvanted Recombinant SARS-CoV-2 Spike (S) Protein Subunit Vaccine (YS-SC2-010)

2021 ◽  
Author(s):  
Yuan Liu ◽  
Nan Zhang ◽  
Bin Wang ◽  
Yi Zhang
Keyword(s):  
South Africa ◽  
Immune Response ◽  
Subunit Vaccine ◽  
Extended Period ◽  
Immune Serum ◽  
Spike Protein ◽  
Protein Subunit ◽  
Neutralization Activity ◽  
The World ◽  
Mutant Strains

Recently SARS-CoV-2 Omicron (B.1.1.529) variant was identified in South Africa with numerous mutations in spike protein, and numerous community infections have been reported and raised grave concern around the world. Some studies found that the neutralization effects of several licensed vaccines against Omicron were dramatically reduced, which significantly affected antibody mediated protection, especially for individuals whose immunization were completed after extended period. In this regard, we studied the persistence and neutralization activity toward mutant strains in animal serum immunized with PIKA-adjuvanted recombinant SARS-CoV-2 spike protein subunit vaccine (YS-SC2-010). Here we are reporting that animal serum collected at 596 days after immunization with YS-SC2-010 still retains high and persistent neutralizing activity against all the Variant of Concern (VOC) variants, including Omicron variant. Although it is a blessed event to achieve 20 months long neutralization against Omicron variant after immunization with YS-SC2-010, it was also founded that the neutralization effect of immune serum on Omicron decreased by 6.29 folds as compared to D614G, more significantly when compared with other mutant strains.

scholarly journals Comparative Structural Analyses of Selected Spike Protein-RBD Mutations in SARS-CoV-2 Lineages

2021 ◽  
Author(s):  
Urmi Roy
Keyword(s):  
South Africa ◽  
Severe Acute Respiratory Syndrome ◽  
Receptor Binding ◽  
Point Mutations ◽  
Spike Protein ◽  
Multiple Point ◽  
Receptor Binding Domain ◽  
Virulent Mutant ◽  
The World ◽  
Mutant Strains

The severity of the covid 19 has been observed throughout the world as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had spread globally claiming more than 2 million lives and left a devastating impact on peoples life. Recently several virulent mutant strains of this virus, such as the B.1.1.7, B.1.351, and P1 lineages have emerged. These strains are predominantly observed in UK, South Africa and Brazil. Another extremely pathogenic B.1.617 lineage and its sub-lineages, first detected in India, are now affecting some countries at notably stronger spread-rates. This paper computationally examines the time-based structures of B.1.1.7, B.1.351, P1 lineages with selected spike protein mutations. Additionally, the mutations in the more recently found B.1.617 lineage and some of its sub-lineages are explored, and the implications for multiple point mutations of the spike proteins receptor-binding domain (RBD) are described.

A Report on COVID-19 Variants, COVID-19 Vaccines and the Impact of the Variants on the Efficacy of the Vaccines

2021 ◽  
Author(s):  
Michael Halim
Keyword(s):  
South Africa ◽  
Immune Response ◽  
Clinical Characteristics ◽  
Systemic Review ◽  
Review Of Literature ◽  
Negative Effects ◽  
Mortality And Morbidity ◽  
The World ◽  
Different Strains ◽  
The Impact

The Coronavirus pandemic has caused negative effects across the globe; mortality and morbidity being the main impact. After WHO, termed the disease a pandemic in March 2020, they gave in health guidelines to follow to control the spread of the disease. The health industry, academia, and different governments are united to develop and test various vaccines at an unprecedented speed to combat the pandemic fully and bring the world back to its feet. Some of the vaccines developed include Pfizer, Moderna, and AstraZeneca. However, just like other viruses, the SAR-CoV-2 virus keeps changing through mutation, as various variants, different from the first one are emerging. Evidence shows that the three new variants; UK, Brazil, and South Africa are more severe in terms of transmissibility, disease severity, evading of the immune response, and reducing the ability to neutralized antibodies, compared to the original coronavirus. With such knowledge of the existence of different strains, the arises concerns on whether the already available vaccines are effective enough in preventing the new COVID-19 strains. Studies are still underdeveloped to learn more on the virologic, epidemiologic, and clinical characteristics of the ever-emerging variants. This research, through a systemic review of literature, seeks to find out whether the variants of SAR-CoV-2 have an impact on the efficacy of various vaccines developed in fighting the disease and the entire body’s immune response.

scholarly journals The N501Y and K417N mutations in the spike protein of SARS-CoV-2 alter the interactions with both hACE2 and human derived antibody: A Free energy of perturbation study

2020 ◽  
Author(s):  
Filip Fratev
Keyword(s):  
South Africa ◽  
Immune Response ◽  
Free Energy ◽  
Molecular Level ◽  
Spike Protein ◽  
Free Energy Perturbation ◽  
Receptor Binding Domain ◽  
Human Immune Response ◽  
Human Immune ◽  
Energy Perturbation

AbstractThe N501Y and K417N mutations in spike protein of SARS-CoV-2 and their combination arise questions but the data about their mechanism of action at molecular level is limited. Here, we present Free energy perturbation (FEP) calculations for the interactions of the spike S1 receptor binding domain (RBD) with both the ACE2 receptor and an antibody derived from COVID-19 patients. Our results shown that the S1 RBD-ACE2 interactions were significantly increased whereas those with the STE90-C11 antibody dramatically decreased; about over 100 times. The K417N mutation had much more pronounced effect and in a combination with N501Y fully abolished the antibody effect. This may explain the observed in UK and South Africa more spread of the virus but also raise an important question about the possible human immune response and the success of already available vaccines.

scholarly journals Next generation vaccine platform: polymersomes as stable nanocarriers for a highly immunogenic and durable SARS-CoV-2 spike protein subunit vaccine

2021 ◽  
Author(s):  
Jian Hang Lam ◽  
Amit Kumar Khan ◽  
Thomas Andrew Cornell ◽  
Regine Josefine Dress ◽  
Teck Wan Chia ◽  
...  
Keyword(s):  
Subunit Vaccine ◽  
Adaptive Immune Response ◽  
Cationic Lipid ◽  
Spike Protein ◽  
Protein Subunit ◽  
Vaccine Platform ◽  
Self Assembling ◽  
Generation Vaccine ◽  
Efficacious Vaccine ◽  
Th1 Cytokines

AbstractMultiple successful vaccines against SARS-CoV-2 are urgently needed to address the ongoing Covid-19 pandemic. In the present work, we describe a subunit vaccine based on the SARS-CoV-2 spike protein co-administered with CpG adjuvant. To enhance the immunogenicity of our formulation, both antigen and adjuvant were encapsulated with our proprietary artificial cell membrane (ACM) polymersome technology. Structurally, ACM polymersomes are self-assembling nanoscale vesicles made up of an amphiphilic block copolymer comprising of polybutadiene-b-polyethylene glycol and a cationic lipid 1,2-dioleoyl-3-trimethylammonium-propane. Functionally, ACM polymersomes serve as delivery vehicles that are efficiently taken up by dendritic cells, which are key initiators of the adaptive immune response. Two doses of our formulation elicit robust neutralizing titers in C57BL/6 mice that persist at least 40 days. Furthermore, we confirm the presence of memory CD4+ and CD8+ T cells that produce Th1 cytokines. This study is an important step towards the development of an efficacious vaccine in humans.

Escape of SARS-CoV-2 501Y.V2 variants from neutralization by convalescent plasma

2021 ◽  
Author(s):  
Sandile Cele ◽  
Inbal Gazy ◽  
Laurelle Jackson ◽  
Shi-Hsia Hwa ◽  
Houriiyah Tegally ◽  
...  
Keyword(s):  
South Africa ◽  
Antibody Response ◽  
Genome Sequencing ◽  
Receptor Binding ◽  
Natural Infection ◽  
Neutralizing Antibody ◽  
Spike Protein ◽  
Whole Genome ◽  
Receptor Binding Domain ◽  
Neutralization Activity

AbstractNew SARS-CoV-2 variants with mutations in the spike glycoprotein have arisen independently at multiple locations and may have functional significance. The combination of mutations in the 501Y.V2 variant first detected in South Africa include the N501Y, K417N, and E484K mutations in the receptor binding domain (RBD) as well as mutations in the N-terminal domain (NTD). Here we address whether the 501Y.V2 variant could escape the neutralizing antibody response elicited by natural infection with earlier variants. We were the first to outgrow two variants of 501Y.V2 from South Africa, designated 501Y.V2.HV001 and 501Y.V2.HVdF002. We examined the neutralizing effect of convalescent plasma collected from six adults hospitalized with COVID-19 using a microneutralization assay with live (authentic) virus. Whole genome sequencing of the infecting virus of the plasma donors confirmed the absence of the spike mutations which characterize 501Y.V2. We infected with 501Y.V2.HV001 and 501Y.V2.HVdF002 and compared plasma neutralization to first wave virus which contained the D614G mutation but no RBD or NTD mutations. We observed that neutralization of the 501Y.V2 variants was strongly attenuated, with IC50 6 to 200-fold higher relative to first wave virus. The degree of attenuation varied between participants and included a knockout of neutralization activity. This observation indicates that 501Y.V2 may escape the neutralizing antibody response elicited by prior natural infection. It raises a concern of potential reduced protection against re-infection and by vaccines designed to target the spike protein of earlier SARS-CoV-2 variants.

scholarly journals A New Vaccine Targeting the S1 of the S Protein Induce Mice Immune Response against COVID-19

2021 ◽  
Author(s):  
Zhen-Wang Jie ◽  
Wei-Hong Sun ◽  
Xiao-Na Wang ◽  
Yu-Ting Lin ◽  
Zi-Yan Zhang ◽  
...  
Keyword(s):  
Immune Response ◽  
Recombinant Protein ◽  
Cell Line ◽  
Efficient Method ◽  
Neutralizing Antibodies ◽  
Hek293 Cell ◽  
Neutralization Activity ◽  
Vaccine Candidates ◽  
The World ◽  
Respiratory Coronavirus

Abstract Coronavirus disease 2019 is pandemic across the world since the severe acute respiratory coronavirus-2 emerged in December 2019. The most efficient method to defend COVID 19 is vaccine. Here, we used HEK293 cell line to produce the recombinant protein and compared several vaccine candidates’ efficiency. The structures of the candidates were designed based on the S1 protein and RBD region. After three doses, the vaccines induced SARS-CoV-2 specific neutralizing antibodies in mice which presented high titers. The maximum neutralization activity could reach more than 90% without inflammation suggesting the great neutralizing ability against SARS-CoV-2.

scholarly journals Delta infection following vaccination elicits potent neutralizing immunity against the SARS-CoV-2 Omicron

2022 ◽  
Author(s):  
Mai-Juan Ma ◽  
Lin Yao ◽  
Hui-Xia Gao ◽  
Ka-Li Zhu ◽  
Jun Rong ◽  
...  
Keyword(s):  
South Africa ◽  
Immune Response ◽  
Immune Escape ◽  
Spike Protein ◽  
Amino Acid Substitutions ◽  
High Potency ◽  
Breakthrough Infection ◽  
Neutralizing Activity ◽  
Humoral Immune ◽  
Delta Infection

Abstract Since the initial detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant (B.1.1.529) in November 2021 in South Africa, it has caused a rapid increase in infections globally. The Omicron variant encodes 37 amino acid substitutions in its spike protein, and early reports have provided evidence for extensive immune escape and reduced vaccine effectiveness. We assessed serum neutralizing activity in sera from Delta infection following vaccination of CoronaVac or ZF2001 and Delta infection only against SARS-CoV-2 Wuhan-Hu-1 (WA1), Beta, Delta, and Omicron. We found that sera from Delta infection only could neutralize WA1 and Delta pseudoviruses but nearly completely lost capacity to neutralize Beta and Omicron pseudoviruses. However, Delta infection following vaccination resulted in a significant increase of serum neutralizing activity against WA1, Beta, and Omicron. This study demonstrates that breakthrough infection of Delta in previously vaccinated individuals substantially induced high potency humoral immune response against the Omicron variant and other emerged variants.

scholarly journals Immunogenicity and Protection Efficacy of Monomeric and Trimeric Recombinant SARS Coronavirus Spike Protein Subunit Vaccine Candidates

2013 ◽  
Vol 26 (2) ◽  
pp. 126-132 ◽  
Author(s):  
Jie Li ◽  
Laura Ulitzky ◽  
Erica Silberstein ◽  
Deborah R. Taylor ◽  
Raphael Viscidi
Keyword(s):  
Subunit Vaccine ◽  
Spike Protein ◽  
Sars Coronavirus ◽  
Protein Subunit ◽  
Vaccine Candidates ◽  
Protection Efficacy

scholarly journals Polymersomes as Stable Nanocarriers for a Highly Immunogenic and Durable SARS-CoV-2 Spike Protein Subunit Vaccine

ACS Nano ◽  
2021 ◽  
Author(s):  
Jian Hang Lam ◽  
Amit K. Khan ◽  
Thomas A. Cornell ◽  
Teck Wan Chia ◽  
Regine J. Dress ◽  
...  
Keyword(s):  
Subunit Vaccine ◽  
Spike Protein ◽  
Protein Subunit

scholarly journals SARS-CoV-2 Immunity: Review of Immune Response to Infection and Vaccination

2021 ◽  
pp. 32-40
Author(s):  
Rahnuma Ahmad
Keyword(s):  
Immune Response ◽  
Vaccine Development ◽  
Current Knowledge ◽  
Multiorgan Failure ◽  
Medical Science ◽  
Neutralizing Antibody ◽  
Spike Protein ◽  
World Population ◽  
The World ◽  
And Function

After the last flu pandemic in 1918, the world has not faced a similar pandemic until now. However, it has been possible to identify the causative agent as well as its structure and function. The SARS-CoV-2 virus attacks the respiratory system, and the viral components like the spike protein and nucleocapsid protein produce an immune response in the host for viral elimination. The antigen can be recognized by or is presented to T cells. This results in neutralizing antibody production, cytokine secretion, and cytolysis. Although most infected individuals only suffer mild or moderate disease, some develop cytokine storms due to excess formation of cytokines resulting in ARDS, multiorgan failure, and DIC. The virus has mechanisms in place that can aid its escape from the host’s immune response. Vaccine development has been underway around the globe to produce effective vaccines to limit morbidity and mortality from infection. Vaccines like mRNA vaccines encode the spike protein of coronavirus, and research has shown that antibodies developing from the vaccine were less affected by mutation in the spike protein of the virus than that developed from infection. The mRNA vaccine has modified nucleotide that limits the excessive formation of Interferons. Although various hurdles to overcome to vaccinate the world population effectively, vaccination may be essential to control the pandemic and a return to normalcy. This review highlights the current knowledge on the structure of the virus and the immune response triggered by the virus in infected individuals. It also reviews the currently available vaccines with their formulation, mechanism of immune response elicited. Bangladesh Journal of Medical Science Vol.20(5) 2021 p.32-40

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