Biology subjects

Sarkale, P.

Publications and source records attributed to Sarkale, P..

6 recordsLinked to original sources

bioRxiv2021

Isolation of SARS-CoV-2 B.1.1.28.2 P2 variant and pathogenicity comparison with D614G variant in hamster model

BackgroundConsidering the potential threat from emerging SARS-CoV-2 variants and the rising COVID-19 cases, SARS-CoV-2 genomic surveillance is ongoing in India. We report herewith the isolation of the P.2 variant (B.1.1.28.2) from international travelers and further its pathogenicity evaluation and comparison with D614G variant (B.1) in hamster model. MethodsVirus isolation was performed in Vero CCL81 cells and genomic characterization by next generation sequencing. The pathogenicity of the isolate was assessed in Syrian hamster model and compared with B.1 variant. ResultsB.1.1.28.2 variant was isolated from nasal/throat swabs of international travelers returned to India from United Kingdom and Brazil. The B.1.1.28.2 variant induced body weight loss, viral replication in the respiratory tract, lung lesions and caused severe lung pathology in infected Syrian hamster model in comparison, with B.1 variant infected hamsters. The sera from B.1.1.28.2 infected hamsters efficiently neutralized the D614G variant virus whereas 6-fold reduction in the neutralization was seen in case of D614G variant infected hamsters sera with the B.1.1.28.2 variant. ConclusionsB.1.1.28.2 lineage variant could be successfully isolated and characterization could be performed. Pathogenicity of the isolate was demonstrated in Syrian hamster model and in comparison, with B.1 variant was found more pathogenic. The findings of increased disease severity and neutralization reduction is of great concern and point towards the need for screening the vaccines for efficacy.

microbiology↗

bioRxiv2021

Isolation and characterization of SARS-CoV-2 VOC, 20H/501Y.V2, from UAE travelers

Multiple SARS-CoV-2 variants have been emerged and created serious public health in the affected countries. The variant of Concern associated with high transmissibility, disease severity and escape mutations is threat to vaccination program across the globe. Travel has been important factor in spread of SARS-CoV-2 variants worldwide. India has also witnessed the dreadful effect of these SARS-CoV-2 variants. Here, we report the Isolation and characterization of SARS-CoV-2 VOC, 20H/501Y.V2 (B.1.351), from UAE travelers to India. The virus isolate would be useful to determine the efficacy of the currently available vaccines in India.

microbiology↗

bioRxiv2021

Possible role of accessory proteins in the viral replication for the 20I/501Y.V1 (B.1.1.7) SARS-CoV-2 variant

The study investigates the replication cycle and transcriptional pattern of the B.1.1.7 variant. It was observed that the B.1.1.7 variant required a longer maturation time. The transcriptional response demonstrated higher expression of ORF6 and ORF8 compared to nucleocapsid transcript till the eclipse period which might influence higher viral replication. The number of infectious viruses titer is higher in the B.1.1.7, despite a lesser copy number than B.1, indicating higher infectivity.

microbiology↗

bioRxiv2021

Comparison of SARS-CoV-2 VOC 202012/01 (UK variant) and D614G variant transmission by different routes in Syrian hamsters

Many SARS-CoV-2 variants of concern has been reported recently which were linked to increased transmission. In our earlier study on virus shedding using VOC 202012/01(UK variant) and D614G variant in hamster model, we observed significantly higher viral RNA shedding through nasal wash in case of UK variant. Hence, we compared the transmission of both the UK and D614G variant by various routes in Syrian hamsters to understand whether the high viral RNA shedding could enhance the transmission efficiency of the variant. The current study demonstrated comparable transmission efficiency of both UK and D614G variants of SARS-CoV-2 in Syrian hamsters.

microbiology↗

bioRxiv2021

Comparison of the pathogenicity and virus shedding of SARS CoV-2 VOC 202012/01 and D614G variant in hamster model

The emergence of SARS-CoV-2 variants has posed a serious challenge to public health system and vaccination programs across the globe. We have studied the pathogenicity and virus shedding pattern of the SARS-CoV-2 VOC 202012/01 and compared with D614G variant in Syrian hamsters. VOC 202012/01 could produce disease in hamsters characterized by body weight loss and respiratory tract tropism but mild lung pathology. Further, we also documented that neutralizing antibodies developed against VOC 202012/01 could equally neutralize D614G variant. Higher load of VOC 202012/01 in the nasal wash specimens was observed during the first week of infection outcompeting the D614G variant. The findings suggest increased fitness of VOC 202012/01 to the upper respiratory tract which could lead to higher transmission. Further investigations are needed to understand the transmissibility of new variants. One-Sentence SummarySARS-CoV-2 VOC 202012/01 infected hamsters demonstrated high viral RNA shedding through the nasal secretions and significant body weight loss with mild lung pathology compared to the D614G variant.

microbiology↗

bioRxiv2021

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

Vaccines 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.

microbiology↗