Isolation and Characterization of Five Severe Acute Respiratory Syndrome Coronavirus 2 Strains of Different Clades and Lineages Circulating in Eastern India

Abstract

The emergence of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) as a serious pandemic has altered the global socioeconomic dynamics. The wide prevalence, high death counts, and rapid emergence of new variants urge for the establishment of research infrastructure to facilitate the rapid development of efficient therapeutic modalities and preventive measures. In agreement with this, SARS-CoV-2 strains were isolated from patient swab samples collected during the first COVID-19 wave in Odisha, India. The viral isolates were adapted to in vitro cultures and further characterized to identify strain-specific variations in viral growth characteristics. The neutralization susceptibility of viral isolates to vaccine-induced antibodies was determined using sera from individuals vaccinated in the Government-run vaccine drive in India. The major goal was to isolate and adapt SARS-CoV-2 viruses in cell culture with minimum modifications to facilitate research activities involved in the understanding of the molecular virology, host–virus interactions, drug discovery, and animal challenge models that eventually contribute toward the development of reliable therapeutics.

Transgenic Mouse Models Establish a Protective Role of Type 1 IFN Response in SARS-CoV-2 infection-related Immunopathology

“…Throughout this study, hemizygous hACE2 mice were used for the SARS-CoV-2 infection. The hACE2 and hACE2 ; Irgm1 −/− were inoculated with 5X10 4 (low-dose) or 5X10 5 (high-dose) plaque-forming units (PFU) via the intranasal route with highly infectious early SARS-CoV-2 strain of clade 19A (Kumar et al, 2021; Singh et al, 2022; Suresh et al, 2021) (Genbank Accession MW559533). For the low-dose experiment, the mice were sacrificed on the 6 and 15 days post-infection (DPI), whereas for the high-dose experiment, mice were sacrificed on the 7 DPI ( Figure 1A ).…”

“…Vero E6 cells were cultured at 37°C in Dulbecco’s Modified Eagle medium (DMEM; Gibco #10569044) supplemented with penicillin/streptomycin (10,000 units/mL) and 10% fetal bovine serum (FBS). SARS-CoV-2 strain of clade 19A was isolated, characterized, and propagated as described previously (Kumar et al, 2021; Singh et al, 2022; Suresh et al, 2021) (Genbank Accession MW559533). The SARS-CoV-2 Delta strain (GISAID ID EPI_ISL_2775201; hCoV-19/India/TG-CCMB-CIA4413/2021) was isolated, characterized, and propagated as described previously (Tandel et al, 2022).…”

SELEX based aptamers with diagnostic and entry inhibitor therapeutic potential for SARS-CoV-2

“…ILS-03 (Accession no. EPI_ISL_1196305) strain of SARS-CoV-2 was successfully isolated and adapted in Vero E6 cells at ILS, Bhubaneswar and this strain was used for this study 19 , 20 .…”

“…To determine the viral copy number and anti-viral effect, qRT-PCR was performed according to a previously described method 19 , 20 . For this, viral RNA was isolated from the supernatants using the TAN Bead Maelstrom 4800 automated RNA extraction platform as per the manufacturer’s instructions and cDNA was synthesized using random hexamers by the Prime Script First strand cDNA synthesis kit (Takara, Kusatsu, Japan).…”

SELEX based aptamers with diagnostic and entry inhibitor therapeutic potential for SARS-CoV-2

“…The sudden outbreak of COVID-19 infection in 2019 not only challenged the global healthcare system but also drastically affected the economic conditions across the world. According to WHO statistics to date, the SARS-CoV-2 virus has affected ~ 600 M people with a mortality rate of more than 1% (6.48 M) 1 . The emergence of variant strains (omicron, delta virus, etc.)…”