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1.
Rev Med Virol ; 32(5): e2346, 2022 09.
Article in English | MEDLINE | ID: covidwho-1782688

ABSTRACT

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), a highly infectious agent associated with unprecedented morbidity and mortality. A failure to stop growth of COVID-19-linked morbidity rates is caused by SARS-CoV-2 mutations and the emergence of new highly virulent SARS-CoV-2 strains. Several acquired SARS-CoV-2 mutations reflect viral adaptations to host immune defence. Mutations in the virus Spike-protein were associated with the lowered effectiveness of current preventive therapies, including vaccines. Recent in vitro studies detected diminished neutralisation capacity of vaccine-induced antibodies, which are targeted to bind Spike receptor-binding and N-terminal domains in the emerging strains. Lower than expected inhibitory activity of antibodies was reported against viruses with E484K Spike mutation, including B.1.1.7 (UK), P.1 (Brazil), B.1.351 (South African), and new Omicron variant (B.1.1.529) with E484A mutation. The vaccine effectiveness is yet to be examined against new mutant strains of SARS-CoV-2 originating in Europe, Nigeria, Brazil, South Africa, and India. To prevent the loss of anti-viral protection in vivo, often defined as antibody resistance, it is required to target highly conserved viral sequences (including Spike protein) and enhance the potency of antibody cocktails. In this review, we assess the reported mutation-acquiring potential of coronaviruses and compare efficacies of current COVID-19 vaccines against 'parent' and 'mutant' strains of SARS-CoV-2 (Kappa (B.1.617.1), Delta (B.1.617.2), and Omicron (B.1.1.529)).


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Humans , SARS-CoV-2/genetics
2.
Virus Res ; 315: 198768, 2022 07 02.
Article in English | MEDLINE | ID: covidwho-1778498

ABSTRACT

COVID-19 caused by SARS-CoV-2 virus has had profound impact on the world in the past two years. Intense research is going on to find effective drugs to combat the disease. Over the past year several vaccines were approved for immunization. But SARS-CoV-2 being an RNA virus is continuously mutating to generate new variants, some of which develop features of immune escape. This raised serious doubts over the long-term efficacy of the vaccines. We have identified a unique mannose binding plant lectin from Narcissus tazetta bulb, NTL-125, which effectively inhibits SARS-CoV-2 replication in Vero-E6 cell line. In silico docking studies revealed that NTL-125 has strong affinity to viral Spike RBD protein, preventing it from attaching to hACE2 receptor, the gateway to cellular entry. Binding analyses revealed that all the mutant variants of Spike protein also have stronger affinity for NTL-125 than hACE2. The unique α-helical tail of NTL-125 plays most important role in binding to RBD of Spike. NTL-125 also interacts effectively with some glycan moieties of S-protein in addition to amino acid residues adding to the binding strength. Thus, NTL-125 is a highly potential antiviral compound of natural origin against SARS-CoV-2 and may serve as an important therapeutic for management of COVID-19.


Subject(s)
Angiotensin-Converting Enzyme 2 , Plant Lectins , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , COVID-19 , Humans , Narcissus/chemistry , Plant Lectins/pharmacology , Protein Binding , SARS-CoV-2/drug effects , Spike Glycoprotein, Coronavirus/antagonists & inhibitors , Spike Glycoprotein, Coronavirus/chemistry
3.
Aging Dis ; 12(8): 2173-2195, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1667753

ABSTRACT

Newly emerging significant SARS-CoV-2 variants such as B.1.1.7, B.1.351, and B.1.1.28 are the variant of concern (VOC) for the human race. These variants are getting challenging to contain from spreading worldwide. Because of these variants, the second wave has started in various countries and is threatening human civilization. Thus, we require efficient vaccines that can combat all emerging variants of SARS-CoV-2. Therefore, we took the initiative to develop a peptide-based next-generation vaccine using four variants (Wuhan variant, B.1.1.7, B.1.351, and B.1.1.28) that could potentially combat SARS-CoV-2 variants. We applied a series of computational tools, servers, and software to identify the most significant epitopes present on the mutagenic regions of SARS-CoV-2 variants. The immunoinformatics approaches were used to identify common B cell derived T cell epitopes, influencing the host immune system. Consequently, to develop a novel vaccine candidate, the antigenic epitopes were linked with a flexible and stable peptide linker, and the adjuvant was added at the N-terminal end. 3D vaccine candidate structure was refined, and quality was assessed using web servers. The physicochemical properties and safety parameters of the vaccine construct were assessed through bioinformatics and immunoinformatics tools. The molecular docking analysis between TLR4/MD2 and the proposed vaccine candidate demonstrated a satisfactory interaction. The molecular dynamics studies confirmed the stability of the vaccine candidate. Finally, we optimized the proposed vaccine through codon optimization and in silico cloning to study the expression. Our multi-epitopic next-generation peptide vaccine construct can boost immunity against the Wuhan variant and all significant mutant variants of SARS-CoV-2.

4.
Journal of Pharmaceutical Research International ; 33(59B):207-214, 2021.
Article in English | Web of Science | ID: covidwho-1629632

ABSTRACT

All healthcare providers have had to adapt and be flexible in order to respond to COVID-19. Nonetheless, the emphasis, particularly at the start of the outbreak, was on the impact and response of secondary and tertiary care. The primary care sectors responsibilities in the response focused on how it could help secondary and tertiary care centers respond. A small percentage of current research and evidence focuses on health services implications or applied public health approaches, with even fewer on the role of primary care and family medicine providers. So, while our scientific understanding of the virus and its subsequent clinical consequences has grown exponentially, information about primary care responses to COVID-19 in a variety of settings, as well as the interaction with patient perspectives and priorities, and broader public health responsibilities, remains significantly hazier.

5.
Math Biosci Eng ; 18(4): 4572-4585, 2021 05 26.
Article in English | MEDLINE | ID: covidwho-1282672

ABSTRACT

AIMS: The main purpose of this study is to explore whether the new variant SARS-CoV-2 VOC 202012/01 in the UK is equipped with some leading or underlying features. METHODS: We apply a systematic and persuasive approach to reveal the underlying dynamical features of this variant. The approach utilises extracting the main features, which consist of 3-valued features, via the time-series data for new cases, 28-day deaths and 60-day deaths. The experimental samples chosen rely on the the rolling sets of regional data vectors whose dimensions are all 7 days. These data sets are projected onto the 3-valued features to yield the vector rejections. Then the minimal features are thus extracted by the minimal total norms. Then we map out the traces of the similarities between all the extracted time-varying features. RESULTS: Our findings, no matter in preliminary or follow-up study, clearly show there is no consistent and substantial shift in the 3-valued features even after the occurrence of this new variant - this might validate the efficacy of the current vaccines against this variant. CONCLUSIONS: Since the underlying features of the mutant is unchanged, and the leading feature of B1.1.7 is not yet present, it might help us make the lockdown decision "choose the lesser of the two evils: pandemic and economic woes", and validate vaccine developments or adopt preventive measures.


Subject(s)
COVID-19 , Communicable Disease Control , Follow-Up Studies , Humans , SARS-CoV-2 , United Kingdom
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