ABSTRACT
Background & objectives: Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has globally affected 195 countries. In India, suspected cases were screened for SARS-CoV-2 as per the advisory of the Ministry of Health and Family Welfare. The objective of this study was to characterize SARS-CoV-2 sequences from three identified positive cases as on February 29, 2020. Methods: Throat swab/nasal swab specimens for a total of 881 suspected cases were screened by E gene and confirmed by RdRp (1), RdRp (2) and N gene real-time reverse transcription-polymerase chain reactions and next-generation sequencing. Phylogenetic analysis, molecular characterization and prediction of B- and T-cell epitopes for Indian SARS-CoV-2 sequences were undertaken. Results: Three cases with a travel history from Wuhan, China, were confirmed positive for SARS-CoV-2. Almost complete (29,851 nucleotides) genomes of case 1, case 3 and a fragmented genome for case 2 were obtained. The sequences of Indian SARS-CoV-2 though not identical showed high (~99.98%) identity with Wuhan seafood market pneumonia virus (accession number: NC 045512). Phylogenetic analysis showed that the Indian sequences belonged to different clusters. Predicted linear B-cell epitopes were found to be concentrated in the S1 domain of spike protein, and a conformational epitope was identified in the receptor-binding domain. The predicted T-cell epitopes showed broad human leucocyte antigen allele coverage of A and B supertypes predominant in the Indian population. Interpretation & conclusions: The two SARS-CoV-2 sequences obtained from India represent two different introductions into the country. The genetic heterogeneity is as noted globally. The identified B- and T-cell epitopes may be considered suitable for future experiments towards the design of vaccines and diagnostics. Continuous monitoring and analysis of the sequences of new cases from India and the other affected countries would be vital to understand the genetic evolution and rates of substitution of the SARS-CoV-2.
Subject(s)
Betacoronavirus/genetics , Genome, Viral , COVID-19 , Coronavirus Infections , Epitopes, B-Lymphocyte/genetics , Epitopes, T-Lymphocyte/genetics , Humans , India , Models, Molecular , Pandemics , Phylogeny , Pneumonia, Viral , Protein Structure, Tertiary , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/geneticsSubject(s)
Betacoronavirus/genetics , Coronavirus Infections/virology , Genome, Viral , Pneumonia, Viral/virology , COVID-19 , China , Humans , India , Iran , Italy , Pandemics , Phylogeny , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2 , Sequence Alignment , TravelSubject(s)
COVID-19 , SARS-CoV-2 , Humans , Microscopy, Electron , Microscopy, Electron, Transmission , TemperatureABSTRACT
We report the development and evaluation of safety and immunogenicity of a whole virion inactivated (WVI) SARS-CoV-2 vaccine (BBV152), adjuvanted with aluminum hydroxide gel (Algel), or TLR7/8 agonist chemisorbed Algel. We used a well-characterized SARS-CoV-2 strain and an established Vero cell platform to produce large-scale GMP-grade highly purified inactivated antigen. Product development and manufacturing process were carried out in a BSL-3 facility. Immunogenicity and safety were determined at two antigen concentrations (3µg and 6µg), with two different adjuvants, in mice, rats, and rabbits. Our results show that BBV152 vaccine formulations generated significantly high antigen-binding and neutralizing antibody titers (NAb), at both concentrations, in all three species with excellent safety profiles. The inactivated vaccine formulation contains TLR7/8 agonist adjuvant-induced Th1-biased antibody responses with elevated IgG2a/IgG1 ratio and increased levels of SARS-CoV-2-specific IFN-γ+ CD4+ T lymphocyte response. Our results support further development for phase I/II clinical trials in humans.
Subject(s)
Betacoronavirus/isolation & purification , Coronavirus Infections/diagnosis , Pneumonia, Viral/diagnosis , Travel , Adenoviruses, Human/isolation & purification , Adolescent , Adult , Aged , COVID-19 , Child , Child, Preschool , Coinfection/diagnosis , Coronavirus Infections/virology , Female , Humans , India , Infant , Infant, Newborn , Influenza A virus/isolation & purification , Influenza B virus/isolation & purification , Male , Metapneumovirus/isolation & purification , Middle Aged , Nasal Cavity/virology , Pandemics , Pharynx/virology , Pneumonia, Viral/virology , Real-Time Polymerase Chain Reaction , Respiratory Syncytial Virus, Human/isolation & purification , Respirovirus/isolation & purification , Rhinovirus/isolation & purification , SARS-CoV-2 , Symptom Assessment , Young AdultABSTRACT
The newly emerged 2019 novel coronavirus (CoV), named as severe acute respiratory syndrome CoV-2 (SARS-CoV-2), like SARS-CoV (now, SARS-CoV-1) and Middle East respiratory syndrome CoV (MERS-CoV), has been associated with high infection rates with over 36,405 deaths. In the absence of approved marketed drugs against coronaviruses, the treatment and management of this novel CoV disease (COVID-19) worldwide is a challenge. Drug repurposing that has emerged as an effective drug discovery approach from earlier approved drugs could reduce the time and cost compared to de novo drug discovery. Direct virus-targeted antiviral agents target specific nucleic acid or proteins of the virus while host-based antivirals target either the host innate immune responses or the cellular machineries that are crucial for viral infection. Both the approaches necessarily interfere with viral pathogenesis. Here we summarize the present status of both virus-based and host-based drug repurposing perspectives for coronaviruses in general and the SARS-CoV-2 in particular.