Immunogenicity and protective potency of Norovirus GII.17 virus-like particle-based vaccine

Noroviruses (NoVs) are a major cause of acute viral gastroenteritis in adults and children worldwide. Lacking of cell culture system and animals models that must be considered the virus like particles (VLPs) used as an effective vaccine development. In the present study, we investigated the expression of the major capsid protein (VP1) of Genogroup II, genotype 17 (GII.17) NoV using recombinant baculovirus system in insect cells and saliva binding blockade assay to detect their protective potency. Our results showed that GII.17 VLPs could be successfully generated in sf9 insect cells and electron microscopic revealed that GII.17 VLPs was visualized as spherical particles of -35nm in diameter. Immunized mouse with purified VLPs produced GII.17 specific sera and could efficiently block GII.17 VLPs binding to saliva histo-blood group antigens (HBGAs). Together, these results suggested that GII.17 VLPs represent a promising vaccine candidate against NoV GII.17 infection and strongly support further preclinical and clinical studies.

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Median infectious dose of human norovirus GII.4 in gnotobiotic pigs is decreased by simvastatin treatment and increased by age

Journal of General Virology ◽

10.1099/vir.0.054080-0 ◽

2013 ◽

Vol 94 (9) ◽

pp. 2005-2016 ◽

Cited By ~ 37

Author(s):

Tammy Bui ◽

Jacob Kocher ◽

Yanru Li ◽

Ke Wen ◽

Guohua Li ◽

...

Keyword(s):

Small Animal ◽

Viral Gastroenteritis ◽

Blood Group Antigens ◽

Genotype 4 ◽

Challenge Virus ◽

Infectious Dose ◽

A Cell ◽

Norovirus Gii ◽

Lowering Drug ◽

Gnotobiotic Pig

Human noroviruses (NoVs), a major cause of viral gastroenteritis, are difficult to study due to the lack of a cell-culture and a small-animal model. Pigs share with humans the types A and H histo-blood group antigens on the intestinal epithelium and have been suggested as a potential model for studies of NoV pathogenesis, immunity and vaccines. In this study, the effects of age and a cholesterol-lowering drug, simvastatin, on the susceptibility of pigs to NoV infection were evaluated. The median infectious dose (ID50) of a genogroup II, genotype 4 (GII.4) 2006b variant was determined. The ID50 in neonatal (4–5 days of age) pigs was ≤2.74×103 viral RNA copies. In older pigs (33–34 days of age), the ID50 was 6.43×104 but decreased to <2.74×103 in simvastatin-fed older pigs. Evidence of NoV infection was obtained by increased virus load in the intestinal contents, cytopathological changes in the small intestine, including irregular microvilli, necrosis and apoptosis, and detection of viral antigen in the tip of villi in duodenum. This GII.4 variant was isolated in 2008 from a patient from whom a large volume of stool was collected. GII.4 NoVs are continuously subjected to selective pressure by human immunity, and antigenically different GII.4 NoV variants emerge every 1–2 years. The determination of the ID50 of this challenge virus is valuable for evaluation of protection against different GII.4 variants conferred by NoV vaccines in concurrence with other GII.4 variants in the gnotobiotic pig model.

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Production of SARS-CoV-2 virus-like particles in insect cells

10.1101/2021.01.30.428979 ◽

2021 ◽

Author(s):

Youjun Mi ◽

Tao Xie ◽

Bingdong Zhu ◽

Jiying Tan ◽

Xuefeng Li ◽

...

Keyword(s):

Escherichia Coli ◽

Human Health ◽

Insect Cells ◽

Vaccine Development ◽

Recombinant Baculovirus ◽

Expression Plasmid ◽

Virus Like Particles ◽

Recombinant Bacmid ◽

Multiple Cloning Sites ◽

S Genes

ABSTRACTCoronavirus disease (COVID-19) causes a serious threat to human health. To production of SARS-COV-2 virus-like particles (VLPs) in insect cells for vaccine development and scientific research. The E, M and S genes were cloned into multiple cloning sites of the new triple expression plasmid with one p10 promoter, two pPH promoters and three multiple cloning sites. The plasmid was transformed into DH10 BacTMEscherichia coli competent cells to obtain recombinant bacmid. Then the recombinant bacmid was transfected in ExpiSf9™ insect cells to generate recombinant baculovirus. After ExpiSf9™ infected with the recombinant baculovirus, the E, M, and S protein co-expressed in insect cells. Finally, SARS-CoV-2 VLPs were self-assembled in insect cells after infection. The morphology and the size of SARS-CoV-2 VLPs are similar to the native virions.

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Hepatitis C Virus Structural Proteins Assemble into Viruslike Particles in Insect Cells

Journal of Virology ◽

10.1128/jvi.72.5.3827-3836.1998 ◽

1998 ◽

Vol 72 (5) ◽

pp. 3827-3836 ◽

Cited By ~ 266

Author(s):

Thomas F. Baumert ◽

Susumu Ito ◽

David T. Wong ◽

T. Jake Liang

Keyword(s):

Hepatitis C Virus ◽

Hepatitis C ◽

Insect Cells ◽

Vaccine Development ◽

Cultured Cells ◽

Recombinant Baculovirus ◽

Structural Proteins ◽

Particle Assembly ◽

Viruslike Particles ◽

Hcv Structural Proteins

ABSTRACT Hepatitis C virus (HCV) is a leading cause of chronic hepatitis in the world. The study of HCV has been hampered by the low level of viral particles in infected individuals, the inability to propagate efficiently the virus in cultured cells, and the lack of a convenient animal model. Due to these obstacles, neither the structure of the virus nor the prerequisites for its assembly have been clearly defined. In this report, we describe a model for the production and purification of HCV-like particles in insect cells using a recombinant baculovirus containing the cDNA of the HCV structural proteins. In insect cells, expressed HCV structural proteins assembled into enveloped viruslike particles (40 to 60 nm in diameter) in large cytoplasmic cisternae, presumably derived from the endoplasmic reticulum. Biophysical characterization of viruslike particles by CsCl and sucrose gradient centrifugation revealed biophysical properties similar to those of putative virions isolated from infected humans. The results suggested that HCV core and envelope proteins without p7 were sufficient for viral particle formation. Analysis of particle-associated nucleic acids demonstrated that HCV RNAs were selectively incorporated into the particles over non-HCV transcripts. The synthesis of HCV-like particles in insect cells may provide an important tool to determine the structural requirements for HCV particle assembly as well as to study viral genome encapsidation and virus-host interactions. The described system may also represent a potential approach toward vaccine development.

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Seroprevalence of parvovirus B19 in urban Chilean children and young adults, 1990 and 1996

Epidemiology and Infection ◽

10.1017/s0950268801006203 ◽

2002 ◽

Vol 128 (1) ◽

pp. 59-62 ◽

Cited By ~ 8

Author(s):

K. ABARCA ◽

B. J. COHEN ◽

P. A. VIAL

Keyword(s):

Young Adults ◽

Insect Cells ◽

Economic Status ◽

Parvovirus B19 ◽

Recombinant Baculovirus ◽

Healthy Children ◽

Immunofluorescence Test ◽

Parvovirus B19 Infection ◽

Children And Young Adults ◽

Capsid Protein Vp1

An immunofluorescence test for detecting parvovirus B19 IgG was developed by infecting insect cells with recombinant baculovirus expressing the capsid protein VP1. The test was used to study the prevalence of antibodies in 725 healthy children and young adults living in Santiago, Chile. In total, 248 sera were taken in 1990 and 477 in 1996. The seroprevalence was low in children less than 5 years old (3% in 1990 and 21% in 1996). It rose during school age to a prevalence around 50%, reaching 60% in young adults. No differences were found between genders. There was a statistically significant higher seroprevalence in the low socio-economic status group in 1990 samples, but this was not observed in 1996. The higher prevalence observed in children less than 5 years of age in 1996 compared with 1990 could be explained by the occurrence of intervening epidemics of parvovirus B19 infection.

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Free Chlorine and Peroxynitrite Alter the Capsid Structure of Human Norovirus GII.4 and Its Capacity to Bind Histo-Blood Group Antigens

Frontiers in Microbiology ◽

10.3389/fmicb.2021.662764 ◽

2021 ◽

Vol 12 ◽

Author(s):

Manon Chassaing ◽

Guillaume Bastin ◽

Maëlle Robin ◽

Didier Majou ◽

Gaël Belliot ◽

...

Keyword(s):

Blood Group ◽

Major Capsid Protein ◽

Free Chlorine ◽

Blood Group Antigens ◽

Cross Links ◽

Two Oxidants ◽

Capsid Protein Vp1 ◽

Norovirus Gii ◽

The Impact ◽

Natural Life

Human noroviruses (HuNoVs) are one of the leading causes of acute gastroenteritis worldwide. HuNoVs are frequently detected in water and foodstuffs. Free chlorine and peroxynitrite (ONOO−) are two oxidants commonly encountered by HuNoVs in humans or in the environment during their natural life cycle. In this study, we defined the effects of these two oxidants on GII.4 HuNoVs and GII.4 virus-like particles (VLPs). The impact on the capsid structure, the major capsid protein VP1 and the ability of the viral capsid to bind to histo-blood group antigens (HBGAs) following oxidative treatments were analyzed. HBGAs are attachment factors that promote HuNoV infection in human hosts. Overall, our results indicate that free chlorine acts on regions involved in the stabilization of VP1 dimers in VLPs and affects their ability to bind to HBGAs. These effects were confirmed in purified HuNoVs. Some VP1 cross-links also take place after free chlorine treatment, albeit to a lesser extent. Not only ONOO− mainly produced VP1 cross-links but can also dissociate VLPs depending on the concentration applied. Nevertheless, ONOO− has less effect on HuNoV particles.

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Production of SARS-CoV-2 Virus-Like Particles in Insect Cells

Vaccines ◽

10.3390/vaccines9060554 ◽

2021 ◽

Vol 9 (6) ◽

pp. 554

Author(s):

Youjun Mi ◽

Tao Xie ◽

Bingdong Zhu ◽

Jiying Tan ◽

Xuefeng Li ◽

...

Keyword(s):

Human Health ◽

Insect Cells ◽

Vaccine Development ◽

Recombinant Baculovirus ◽

Expression Plasmid ◽

Virus Like Particles ◽

Competent Cells ◽

Recombinant Bacmid ◽

Multiple Cloning Sites ◽

S Genes

Coronavirus disease (COVID-19) causes a serious threat to human health. Virus-like particles (VLPs) constitute a promising platform in SARS-CoV-2 vaccine development. In this study, the E, M, and S genes were cloned into multiple cloning sites of a new triple expression plasmid with one p10 promoter, two pPH promoters, and three multiple cloning sites. The plasmid was transformed into DH10 BacTMEscherichia coli competent cells to obtain recombinant bacmid. Then the recombinant bacmid was transfected in ExpiSf9TM insect cells to generate recombinant baculovirus. After ExpiSf9TM cells infection with the recombinant baculovirus, the E, M, and S proteins were expressed in insect cells. Finally, SARS-CoV-2 VLPs were self-assembled in insect cells after infection. The morphology and the size of SARS-CoV-2 VLPs are similar to the native virions.

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The Immune Correlates of Orthohantavirus Vaccine

Vaccines ◽

10.3390/vaccines9050518 ◽

2021 ◽

Vol 9 (5) ◽

pp. 518

Author(s):

Joon-Yong Bae ◽

Jin Il Kim ◽

Mee Sook Park ◽

Gee Eun Lee ◽

Heedo Park ◽

...

Keyword(s):

Vaccine Development ◽

Zoonotic Transmission ◽

Effective Vaccine ◽

Pandemic Preparedness ◽

Relative Paucity ◽

Immune Correlates ◽

Current Vaccine ◽

Pros And Cons ◽

Human Infections ◽

Sense Of Urgency

Zoonotic transmission of orthohantaviruses from rodent reservoirs to humans has been the cause of severe fatalities. Human infections are reported worldwide, but vaccines have been approved only in China and Korea. Orthohantavirus vaccine development has been pursued with no sense of urgency due to the relative paucity of cases in countries outside China and Korea. However, the orthohantaviruses continuously evolve in hosts and thus the current vaccine may not work as well against some variants. Therefore, a more effective vaccine should be prepared against the orthohantaviruses. In this review, we discuss the issues caused by the orthohantavirus vaccine. Given the pros and cons of the orthohantavirus vaccine, we suggest strategies for the development of better vaccines in terms of pandemic preparedness.

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Strategies for Vaccination: Conventional Vaccine Approaches Versus New-Generation Strategies in Combination with Adjuvants

Pharmaceutics ◽

10.3390/pharmaceutics13020140 ◽

2021 ◽

Vol 13 (2) ◽

pp. 140

Author(s):

Abdellatif Bouazzaoui ◽

Ahmed A. H. Abdellatif ◽

Faisal A. Al-Allaf ◽

Neda M. Bogari ◽

Saied Al-Dehlawi ◽

...

Keyword(s):

Viral Vectors ◽

Protein Production ◽

Vaccine Development ◽

Effective Vaccine ◽

The Novel ◽

Research Teams ◽

Advantages And Disadvantages ◽

Rapid Spread ◽

New Generation ◽

Conventional Vaccine

The current COVID-19 pandemic, caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2), has raised significant economic, social, and psychological concerns. The rapid spread of the virus, coupled with the absence of vaccines and antiviral treatments for SARS-CoV-2, has galvanized a major global endeavor to develop effective vaccines. Within a matter of just a few months of the initial outbreak, research teams worldwide, adopting a range of different strategies, embarked on a quest to develop effective vaccine that could be effectively used to suppress this virulent pathogen. In this review, we describe conventional approaches to vaccine development, including strategies employing proteins, peptides, and attenuated or inactivated pathogens in combination with adjuvants (including genetic adjuvants). We also present details of the novel strategies that were adopted by different research groups to successfully transfer recombinantly expressed antigens while using viral vectors (adenoviral and retroviral) and non-viral delivery systems, and how recently developed methods have been applied in order to produce vaccines that are based on mRNA, self-amplifying RNA (saRNA), and trans-amplifying RNA (taRNA). Moreover, we discuss the methods that are being used to enhance mRNA stability and protein production, the advantages and disadvantages of different methods, and the challenges that are encountered during the development of effective vaccines.

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Linear B-Cell Epitopes in Human Norovirus GII.4 Capsid Protein Elicit Blockade Antibodies

Vaccines ◽

10.3390/vaccines9010052 ◽

2021 ◽

Vol 9 (1) ◽

pp. 52

Author(s):

Hassan Moeini ◽

Suliman Qadir Afridi ◽

Sainitin Donakonda ◽

Percy A. Knolle ◽

Ulrike Protzer ◽

...

Keyword(s):

B Cell ◽

Capsid Protein ◽

Immune Escape ◽

Solvent Accessibility ◽

Effective Vaccine ◽

Blood Group Antigens ◽

Human Norovirus ◽

B Cell Epitopes ◽

Blocking Rate ◽

Linear B

Human norovirus (HuNoV) is the leading cause of nonbacterial gastroenteritis worldwide with the GII.4 genotype accounting for over 80% of infections. The major capsid protein of GII.4 variants is evolving rapidly, resulting in new epidemic variants with altered antigenic potentials that must be considered for the development of an effective vaccine. In this study, we identify and characterize linear blockade B-cell epitopes in HuNoV GII.4. Five unique linear B-cell epitopes, namely P2A, P2B, P2C, P2D, and P2E, were predicted on the surface-exposed regions of the capsid protein. Evolving of the surface-exposed epitopes over time was found to correlate with the emergence of new GII.4 outbreak variants. Molecular dynamic simulation (MD) analysis and molecular docking revealed that amino acid substitutions in the putative epitopes P2B, P2C, and P2D could be associated with immune escape and the appearance of new GII.4 variants by affecting solvent accessibility and flexibility of the antigenic sites and histo-blood group antigens (HBAG) binding. Testing the synthetic peptides in wild-type mice, epitopes P2B (336–355), P2C (367–384), and P2D (390–400) were recognized as GII.4-specific linear blockade epitopes with the blocking rate of 68, 55 and 28%, respectively. Blocking rate was found to increase to 80% using the pooled serum of epitopes P2B and P2C. These data provide a strategy for expanding the broad blockade potential of vaccines for prevention of NoV infection.

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SARS-CoV-2 vaccines strategies: a comprehensive review of phase 3 candidates

npj Vaccines ◽

10.1038/s41541-021-00292-w ◽

2021 ◽

Vol 6 (1) ◽

Cited By ~ 3

Author(s):

Nikolaos C. Kyriakidis ◽

Andrés López-Cortés ◽

Eduardo Vásconez González ◽

Alejandra Barreto Grimaldos ◽

Esteban Ortiz Prado

Keyword(s):

Neutralizing Antibodies ◽

Large Scale ◽

Vaccine Development ◽

Rna Virus ◽

Protein S ◽

Effective Vaccine ◽

Phase 3 ◽

Vaccine Candidates ◽

Advantages And Disadvantages ◽

The World

AbstractThe new SARS-CoV-2 virus is an RNA virus that belongs to the Coronaviridae family and causes COVID-19 disease. The newly sequenced virus appears to originate in China and rapidly spread throughout the world, becoming a pandemic that, until January 5th, 2021, has caused more than 1,866,000 deaths. Hence, laboratories worldwide are developing an effective vaccine against this disease, which will be essential to reduce morbidity and mortality. Currently, there more than 64 vaccine candidates, most of them aiming to induce neutralizing antibodies against the spike protein (S). These antibodies will prevent uptake through the human ACE-2 receptor, thereby limiting viral entrance. Different vaccine platforms are being used for vaccine development, each one presenting several advantages and disadvantages. Thus far, thirteen vaccine candidates are being tested in Phase 3 clinical trials; therefore, it is closer to receiving approval or authorization for large-scale immunizations.

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