The Brucella abortus S19 ΔvjbR Live Vaccine Candidate Is Safer than S19 and Confers Protection against Wild-Type Challenge in BALB/c Mice When Delivered in a Sustained-Release Vehicle

ABSTRACT Brucellosis is an important zoonotic disease of nearly worldwide distribution. Despite the availability of live vaccine strains for bovine (S19, RB51) and small ruminants (Rev-1), these vaccines have several drawbacks, including residual virulence for animals and humans. Safe and efficacious immunization systems are therefore needed to overcome these disadvantages. A vjbR knockout was generated in the S19 vaccine and investigated for its potential use as an improved vaccine candidate. Vaccination with a sustained-release vehicle to enhance vaccination efficacy was evaluated utilizing the live S19 ΔvjbR::Kan in encapsulated alginate microspheres containing a nonimmunogenic eggshell precursor protein of the parasite Fasciola hepatica (vitelline protein B). BALB/c mice were immunized intraperitoneally with either encapsulated or nonencapsulated S19 ΔvjbR::Kan at a dose of 1 × 105 CFU per animal to evaluate immunogenicity, safety, and protective efficacy. Humoral responses postvaccination indicate that the vaccine candidate was able to elicit an anti-Brucella-specific immunoglobulin G response even when the vaccine was administered in an encapsulated format. The safety was revealed by the absence of splenomegaly in mice that were inoculated with the mutant. Finally, a single dose with the encapsulated mutant conferred higher levels of protection compared to the nonencapsulated vaccine. These results suggest that S19 ΔvjbR::Kan is safer than S19, induces protection in mice, and should be considered as a vaccine candidate when administered in a sustained-release manner.

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Reduction in Oviposition of Poultry Red Mite (Dermanyssus gallinae) in Hens Vaccinated with Recombinant Akirin

Vaccines ◽

10.3390/vaccines7030121 ◽

2019 ◽

Vol 7 (3) ◽

pp. 121 ◽

Cited By ~ 6

Author(s):

Jose Lima-Barbero ◽

Marinela Contreras ◽

Kathryn Bartley ◽

Daniel Price ◽

Francesca Nunn ◽

...

Keyword(s):

Egg Production ◽

Protective Antigen ◽

Vaccine Candidate ◽

Protective Efficacy ◽

Egg Yolk ◽

Economic Losses ◽

Dermanyssus Gallinae ◽

Poultry Red Mite ◽

Production Sector ◽

Worldwide Distribution

The poultry red mite (PRM), Dermanyssus gallinae, is a hematophagous ectoparasite of birds with worldwide distribution that causes economic losses in the egg-production sector of the poultry industry. Traditional control methods, mainly based on acaricides, have been only partially successful, and new vaccine-based interventions are required for the control of PRM. Vaccination with insect Akirin (AKR) and its homolog in ticks, Subolesin (SUB), have shown protective efficacy for the control of ectoparasite infestations and pathogen infection/transmission. The aim of this study was the identification of the akr gene from D. gallinae (Deg-akr), the production of the recombinant Deg-AKR protein, and evaluation of its efficacy as a vaccine candidate for the control of PRM. The anti-Deg-AKR serum IgY antibodies in hen sera and egg yolk were higher in vaccinated than control animals throughout the experiment. The results demonstrated the efficacy of the vaccination with Deg-AKR for the control of PRM by reducing mite oviposition by 42% following feeding on vaccinated hens. A negative correlation between the levels of serum anti-Deg-AKR IgY and mite oviposition was obtained. These results support Deg-AKR as a candidate protective antigen for the control of PRM population growth.

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Protective Efficacy and Safety of Brucella melitensis 16MΔmucRagainst Intraperitoneal and Aerosol Challenge in BALB/c Mice

Infection and Immunity ◽

10.1128/iai.05330-11 ◽

2011 ◽

Vol 79 (9) ◽

pp. 3653-3658 ◽

Cited By ~ 21

Author(s):

A. M. Arenas-Gamboa ◽

A. C. Rice-Ficht ◽

M. M. Kahl-McDonagh ◽

T. A. Ficht

Keyword(s):

Vaccine Candidate ◽

Brucella Melitensis ◽

Protective Efficacy ◽

Significant Degree ◽

Content Type ◽

Degree Of Protection ◽

Worldwide Distribution ◽

Human Use ◽

Identification And Characterization

ABSTRACTBrucellosis is a zoonosis of nearly worldwide distribution. Vaccination against this pathogen is an important control strategy to prevent the disease. Currently licensed vaccine strains used in animals are unacceptable for human use due to undesirable side effects and modest protection. Substantial progress has been made during the past 10 years toward the development of improved vaccines for brucellosis. In part, this has been achieved by the identification and characterization of live attenuated mutants that are safer in the host but still can stimulate an adequate immune response. In the present study, the identification and characterization of themucRmutant (BMEI 1364) as a vaccine candidate for brucellosis was conducted. BALB/c mice were vaccinated intraperitoneally at a dose of 105CFU with the mutant to evaluate safety and protective efficacy against intraperitoneal and aerosol challenge. All animals vaccinated with the vaccine candidate demonstrated a statistically significant degree of protection against both intraperitoneal and aerosol challenge. Safety was revealed by the absence ofBrucellaassociated pathological changes, including splenomegaly, hepatomegaly, or granulomatous disease. These results suggest that the 16MΔmucRvaccine is safe, elicits a strong protective immunity, and should be considered as a promising vaccine candidate for human use.

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Construction, characterization and evaluation of the protective efficacy of the Streptococcus suis double mutant strain ΔSsPep/ΔSsPspC as a live vaccine candidate in mice

Microbiological Research ◽

10.1016/j.micres.2014.08.010 ◽

2015 ◽

Vol 170 ◽

pp. 87-94 ◽

Cited By ~ 11

Author(s):

Jin Hu ◽

Wujin You ◽

Bin Wang ◽

Xueying Hu ◽

Chen Tan ◽

...

Keyword(s):

Mutant Strain ◽

Double Mutant ◽

Vaccine Candidate ◽

Protective Efficacy ◽

Streptococcus Suis ◽

Live Vaccine ◽

Double Mutant Strain

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Secondary Metabolites from Artemisia Genus as Biopesticides and Innovative Nano-Based Application Strategies

Molecules ◽

10.3390/molecules26103061 ◽

2021 ◽

Vol 26 (10) ◽

pp. 3061

Author(s):

Bianca Ivănescu ◽

Ana Flavia Burlec ◽

Florina Crivoi ◽

Crăița Roșu ◽

Andreia Corciovă

Keyword(s):

Secondary Metabolites ◽

Negative Impact ◽

Crop Protection ◽

Duration Of Action ◽

Worldwide Distribution ◽

Artemisia Species ◽

Extended Duration ◽

Reduced Toxicity ◽

Available Information ◽

Potential Use

The Artemisia genus includes a large number of species with worldwide distribution and diverse chemical composition. The secondary metabolites of Artemisia species have numerous applications in the health, cosmetics, and food sectors. Moreover, many compounds of this genus are known for their antimicrobial, insecticidal, parasiticidal, and phytotoxic properties, which recommend them as possible biological control agents against plant pests. This paper aims to evaluate the latest available information related to the pesticidal properties of Artemisia compounds and extracts and their potential use in crop protection. Another aspect discussed in this review is the use of nanotechnology as a valuable trend for obtaining pesticides. Nanoparticles, nanoemulsions, and nanocapsules represent a more efficient method of biopesticide delivery with increased stability and potency, reduced toxicity, and extended duration of action. Given the negative impact of synthetic pesticides on human health and on the environment, Artemisia-derived biopesticides and their nanoformulations emerge as promising ecofriendly alternatives to pest management.

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Immunogenicity, Genetic Stability, and Protective Efficacy of a Recombinant, Chimeric Yellow Fever-Japanese Encephalitis Virus (ChimeriVax-JE) as a Live, Attenuated Vaccine Candidate against Japanese Encephalitis

Virology ◽

10.1006/viro.1999.9695 ◽

1999 ◽

Vol 257 (2) ◽

pp. 363-372 ◽

Cited By ~ 123

Author(s):

F. Guirakhoo ◽

Z.-X. Zhang ◽

T.J. Chambers ◽

S. Delagrave ◽

J. Arroyo ◽

...

Keyword(s):

Japanese Encephalitis Virus ◽

Yellow Fever ◽

Japanese Encephalitis ◽

Genetic Stability ◽

Vaccine Candidate ◽

Protective Efficacy ◽

Encephalitis Virus ◽

Live Attenuated Vaccine ◽

Attenuated Vaccine

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Construction and characterization of a replication-competent human adenovirus type 3-based vector as a live-vaccine candidate and a viral delivery vector

Vaccine ◽

10.1016/j.vaccine.2008.12.039 ◽

2009 ◽

Vol 27 (8) ◽

pp. 1145-1153 ◽

Cited By ~ 32

Author(s):

Qiwei Zhang ◽

Xiaobo Su ◽

Donald Seto ◽

Bo-jian Zheng ◽

Xingui Tian ◽

...

Keyword(s):

Vaccine Candidate ◽

Human Adenovirus ◽

Adenovirus Type ◽

Live Vaccine ◽

Delivery Vector ◽

Type 3

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Assessment of immunogenicity and protective efficacy of ZyCoV-D DNA vaccine candidates in Rhesus macaques against SARS-CoV-2 infection

10.1101/2021.02.02.429480 ◽

2021 ◽

Author(s):

Pragya D Yadav ◽

Sanjay Kumar ◽

Kshitij Agarwal ◽

Mukul Jain ◽

Dilip R Patil ◽

...

Keyword(s):

Vaccine Candidate ◽

Protective Efficacy ◽

Rhesus Macaques ◽

Herd Immunity ◽

Lavage Fluid ◽

Injection System ◽

Protective Measure ◽

Vaccine Candidates ◽

Virus Challenge ◽

Syringe Needle

AbstractVaccines remain the key protective measure to achieve herd immunity to control the disease burden and stop COVID-19 pandemic. We have developed and assessed the immunogenicity and protective efficacy of two formulations (1mg and 2mg) of ZyCoV-D (a plasmid DNA based vaccine candidates) administered through Needle Free Injection System (NFIS) and syringe-needle (intradermal) in rhesus macaques with three dose vaccine regimens. The vaccine candidate 2mg dose administered using Needle Free Injection System (NFIS) elicited a significant immune response with development of SARS-CoV-2 S1 spike region specific IgG and neutralizing antibody (NAb) titers during the immunization phase and significant enhancement in the levels after the virus challenge. In 2 mg NFIS group the IgG and NAb titers were maintained and showed gradual rise during the immunization period (15 weeks) and till 2 weeks after the virus challenge. It also conferred better protection to macaques evident by the viral clearance from nasal swab, throat swab and bronchoalveolar lavage fluid specimens in comparison with macaques from other immunized groups. In contrast, the animals from placebo group developed high levels of viremia and lung disease following the virus challenge. Besides this, the vaccine candidate also induced increase lymphocyte proliferation and cytokines response (IL-6, IL-5).The administration of the vaccine candidate with NFIS generated a better immunogenicity response in comparison to syringe-needle (intradermal route). The study demonstrated immunogenicity and protective efficacy of the vaccine candidate, ZyCoV-D in rhesus macaques.

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Development and evaluation of in murine model, of an improved live-vaccine candidate against brucellosis from to Brucella melitensis vjbR deletion mutant

Microbial Pathogenesis ◽

10.1016/j.micpath.2018.08.052 ◽

2018 ◽

Vol 124 ◽

pp. 250-257 ◽

Cited By ~ 4

Author(s):

Zhiqiang Li ◽

Shuli Wang ◽

Hui Zhang ◽

Li Xi ◽

Jinliang Zhang ◽

...

Keyword(s):

Murine Model ◽

Deletion Mutant ◽

Vaccine Candidate ◽

Brucella Melitensis ◽

Live Vaccine

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Adaptation of SARS-CoV-2 in BALB/c mice for testing vaccine efficacy

Science ◽

10.1126/science.abc4730 ◽

2020 ◽

pp. eabc4730 ◽

Cited By ~ 22

Author(s):

Hongjing Gu ◽

Qi Chen ◽

Guan Yang ◽

Lei He ◽

Hang Fan ◽

...

Keyword(s):

Vaccine Candidate ◽

Inflammatory Responses ◽

Protective Efficacy ◽

Small Animal ◽

Spike Protein ◽

Mouse Lung ◽

Receptor Binding Domain ◽

Intranasal Inoculation ◽

Adaptive Mutations ◽

Small Animal Models

The ongoing COVID-19 pandemic has prioritized the development of small animal models for SARS-CoV-2. Herein, we adapted a clinical isolate of SARS-CoV-2 by serial passaging in the respiratory tract of aged BALB/c mice. The resulting mouse-adapted strain at passage 6 (termed MASCp6) showed increased infectivity in mouse lung, and led to interstitial pneumonia and inflammatory responses in both young and aged mice following intranasal inoculation. Deep sequencing revealed a panel of adaptive mutations potentially associated with the increased virulence. In particular, the N501Y mutation is located at the receptor binding domain (RBD) of the spike protein. The protective efficacy of a recombinant RBD vaccine candidate was validated using this model. Thus, this mouse-adapted strain and associated challenge model should be of value in evaluating vaccines and antivirals against SARS-CoV-2.

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