The Challenges of Vaccine Development against Betacoronaviruses: Antibody Dependent Enhancement and Sendai Virus as a Possible Vaccine Vector
To design an effective and safe vaccine against betacoronaviruses, it is necessary to use their evolutionarily conservative antigenic determinants that will elicit the combination of strong humoral and cell-mediated immune responses. Targeting such determinants minimizes the risk of antibody-dependent enhancement of viral infection.
This phenomenon was observed in animal trials of experimental vaccines against SARS-CoV-1 and MERS-CoV that were developed based on inactivated coronavirus or vector constructs expressing the spike protein (S) of the virion.
The substitution and glycosylation of certain amino acids in the antigenic determinants of the S-protein, as well as its conformational changes, can lead to the same effect in a new experimental vaccine against SARS-CoV-2. Using more conservative structural and accessory viral proteins for the vaccine antigenic determinants will help to avoid this problem.
This review outlines approaches for developing vaccines against the new SARS-CoV-2 coronavirus that are based on non-pathogenic viral vectors. For efficient prevention of infections caused by respiratory pathogens the ability of the vaccine to stimulate mucosal immunity in the respiratory tract is important.
Such a vaccine can be developed using non-pathogenic Sendai virus vector, since it can be administered intranasally and induce a mucosal immune response that strengthens the antiviral barrier in the respiratory tract and provides reliable protection against infection.
Description: Novel Coronavirus (2019-nCoV) Real Time RT-PCR Kit is used for the qualitative detection of a novel coronavirus, which was identified in 2019 at Wuhan City, Hubei Province, China, in upper respiratory tract specimens (nasopharyngeal extracts, deep cough sputum, etc.) and lower respiratory tract specimens (alveoli irrigation fluid, etc.) by real time PCR systems.
Description: Novel Coronavirus (2019-nCoV) Real Time Multiplex RT-PCR Kit is used for the qualitative detection of a novel coronavirus, which was identified in 2019 at Wuhan City, Hubei Province, China, in upper respiratory tract specimens (nasopharyngeal extracts, deep cough sputum, etc.) and lower respiratory tract specimens (alveoli irrigation fluid, etc.) by real time PCR systems. It detects N gene, E gene and RdRp gene of 2019-nCoV. RR-0479-02 has been also approverd by CFDA for emergency use and is WHO standard.
Development of High Resolution DNA Melting Analysis for Simultaneous Detection of Potato Mop-Top Virus and Its Vector, Spongospora subterranea, in Soil
In this study, a set of duplex reverse transcription (RT)-PCR-mediated high resolution DNA melting (HRM) analyses for simultaneous detection of potato mop-virus (PMTV) and its protist vector, Spongospora subterranea f.sp. subterranea (Sss), was developed.
The infestation of soil by PMTV was detected by using a tobacco-based baiting system. Total RNA extracted from the soil led to successful RT-PCR gel-electrophoresis detection of both PMTV and Sss.
To facilitate more efficient detection, newly designed primer pairs for PMTV RNA species (i.e., RNA-Rep, -CP, and -TGB) were analyzed together with the existing Sss primers using real-time RT-PCR. The resulting amplicons exhibited melting profiles that could be readily differentiated.
Under duplex RT-PCR format, all PMTV and Sss primer combinations led to successful detection of respective PMTV RNA species and Sss in the samples by high resolution DNA melting (HRM) analyses.
When the duplex HRM assay was applied to soil samples collected from six fields at four different sites in New Brunswick, Canada, positive detection of PMTV and/or Sss was found in 63-100% samples collected from fields in which PMTV-infected tubers had been observed.
In contrast, the samples from fields where neither PMTV- nor Sss-infected tubers had been observed resulted in negative detection by the assay. Bait tobacco bioassay for PMTV and Sss produced similar results.
Between 63%-83% and 100% of the soil samples collected from PMTV-infested fields led to PMTV and Sss infections in the bait tobacco plants, respectively; whereas no PMTV or Sss infected plants were obtained from soil samples collected from PMTV/Sss-free fields.
The Brighton Collaboration standardized template for collection of key information for benefit-risk assessment of viralvector vaccines
Many of the vaccines under development for COVID-19 involve the use of viral vectors. The Brighton Collaboration Benefit-Risk Assessment of Vaccines by Technology (BRAVATO, formerly the Viral Vector Vaccine Safety Working Group, V3SWG) working group has prepared a standardized template to describe the key considerations for the benefit-risk assessment of viral vector vaccines.
This will facilitate key stakeholders to anticipate potential safety issues and interpret or assess safety data. This would also help improve communication and public acceptance of licensed viral vector vaccines.
qPCR ProbesMaster UNGMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
Description: qPCR ProbesMaster UNGMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
qPCR ProbesMaster highROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2x conc. master mix** shipped ice packs - must be shipped via overnight service
Description: qPCR ProbesMaster highROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2x conc. master mix** shipped ice packs - must be shipped via overnight service
qPCR ProbesMaster highROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2x conc. master mix** shipped ice packs - must be shipped via overnight service
Description: qPCR ProbesMaster highROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2x conc. master mix** shipped ice packs - must be shipped via overnight service
qPCR ProbesMaster lowROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
Description: qPCR ProbesMaster lowROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
qPCR ProbesMaster lowROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
Description: qPCR ProbesMaster lowROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
qPCR ProbesMaster UNG lowROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
Description: qPCR ProbesMaster UNG lowROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
qPCR ProbesMaster UNG lowROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
Description: qPCR ProbesMaster UNG lowROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
qPCR ProbesMaster UNG highROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
Description: qPCR ProbesMaster UNG highROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
qPCR ProbesMaster UNG highROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service
Description: qPCR ProbesMaster UNG highROXMaster mix for quantitative real-time PCR using labeled DNA probes, 2 x conc. master mix** shipped ice packs - must be shipped via overnight service