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1.
Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India ; : 1-1, 2023.
Article in English | EuropePMC | ID: covidwho-20238261
2.
Indian J Otolaryngol Head Neck Surg ; : 1, 2023 May 24.
Article in English | MEDLINE | ID: covidwho-20238262

ABSTRACT

[This corrects the article DOI: 10.1007/s12070-022-03310-y.].

3.
Indian J Otolaryngol Head Neck Surg ; : 1, 2023 May 24.
Article in English | MEDLINE | ID: covidwho-20238260

ABSTRACT

[This corrects the article DOI: 10.1007/s12070-022-03310-y.].

4.
Heliyon ; 9(5): e15587, 2023 May.
Article in English | MEDLINE | ID: covidwho-2299164

ABSTRACT

The COVID-19 pandemic continues to threaten human health worldwide as new variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerge. Currently, the predominant circulating strains around the world are Omicron variants, which can evade many therapeutic antibodies. Thus, the development of new broadly neutralizing antibodies remains an urgent need. In this work, we address this need by using the mRNA-lipid nanoparticle immunization method to generate a set of Omicron-targeting monoclonal antibodies. Five of our novel K-RBD-mAbs show strong binding and neutralizing activities toward all SARS-CoV-2 variants of concern (Alpha, Beta, Gamma, Delta and Omicron). Notably, the epitopes of these five K-RBD-mAbs are overlapping and localized around Y453 and F486 of the spike protein receptor binding domain (RBD). Chimeric derivatives of the five antibodies (K-RBD-chAbs) neutralize Omicron sublineages BA.1 and BA.2 with low IC50 values ranging from 5.7 to 12.9 ng/mL. Additionally, we performed antibody humanization on broadly neutralizing chimeric antibodies to create K-RBD-hAb-60 and -62, which still retain excellent neutralizing activity against Omicron. Our results collectively suggest that these five therapeutic antibodies may effectively combat current and emerging SARS-CoV-2 variants, including Omicron BA.1 and BA.2. Therefore, the antibodies can potentially be used as universal neutralizing antibodies against SARS-CoV-2.

5.
J Biomed Sci ; 29(1): 108, 2022 Dec 22.
Article in English | MEDLINE | ID: covidwho-2266799

ABSTRACT

BACKGROUND: The variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) harbor diverse spike (S) protein sequences, which can greatly influence the efficacies of therapeutics. Therefore, it would be of great value to develop neutralizing monoclonal antibodies (mAbs) that can broadly recognize multiple variants. METHODS: Using an mRNA-LNP immunization strategy, we generated several mAbs that specifically target the conserved S2 subunit of SARS-CoV-2 (B-S2-mAbs). These mAbs were assessed for their neutralizing activity with pseudotyped viruses and binding ability for SARS-CoV-2 variants. RESULTS: Among these mAbs, five exhibited strong neutralizing ability toward the Gamma variant and also recognized viral S proteins from the Wuhan, Alpha, Beta, Gamma, Delta and Omicron (BA.1, BA.2 and BA.5) variants. Furthermore, we demonstrated the broad reactivities of these B-S2-mAbs in several different applications, including immunosorbent, immunofluorescence and immunoblotting assays. In particular, B-S2-mAb-2 exhibited potent neutralization of Gamma variant (IC50 = 0.048 µg/ml) in a pseudovirus neutralization assay. The neutralizing epitope of B-S2-mAb-2 was identified by phage display as amino acid residues 1146-1152 (DSFKEEL) in the S2 subunit HR2 domain of SARS-CoV-2. CONCLUSION: Since there are not many mAbs that can bind the S2 subunit of SARS-CoV-2 variants, our set of B-S2-mAbs may provide important materials for basic research and potential clinical applications. Importantly, our study results demonstrate that the viral S2 subunit can be targeted for the production of cross-reactive antibodies, which may be used for coronavirus detection and neutralization.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , Antibodies, Viral , Antibodies, Monoclonal/metabolism , Spike Glycoprotein, Coronavirus/genetics , Antibodies, Neutralizing
6.
Int J Pharm ; 627: 122256, 2022 Nov 05.
Article in English | MEDLINE | ID: covidwho-2049315

ABSTRACT

Throughout the COVID-19 pandemic, many prophylactic and therapeutic drugs have been evaluated and introduced. Among these treatments, monoclonal antibodies (mAbs) that bind to and neutralize SARS-CoV-2 virus have been applied as complementary and alternative treatments to vaccines. Although different methodologies have been utilized to produce mAbs, traditional hybridoma fusion technology is still commonly used for this purpose due to its unmatched performance record. In this study, we coupled the hybridoma fusion strategy with mRNA-lipid nanoparticle (LNP) immunization. This time-saving approach can circumvent biological and technical hurdles, such as difficult-to-express membrane proteins, antigen instability, and the lack of posttranslational modifications on recombinant antigens. We used mRNA-LNP immunization and hybridoma fusion technology to generate mAbs against the receptor binding domain (RBD) of SARS-CoV-2 spike (S) protein. Compared with traditional protein-based immunization approaches, inoculation of mice with RBD mRNA-LNP induced higher titers of serum antibodies and markedly increased serum neutralizing activity. The mAbs we obtained can bind to SARS-CoV-2 RBDs from several variants. Notably, RBD-mAb-3 displayed particularly high binding affinities and neutralizing potencies against both Alpha and Delta variants. In addition to introducing specific mAbs against SARS-CoV-2, our data generally demonstrate that mRNA-LNP immunization may be useful to quickly generate highly functional mAbs against emerging infectious diseases.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Mice , Animals , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Antibodies, Neutralizing/chemistry , Antibodies, Neutralizing/metabolism , Pandemics , Antibody Formation , RNA, Messenger , COVID-19/prevention & control , Antibodies, Viral , Antibodies, Monoclonal/chemistry , Immunization
7.
J Biomed Sci ; 29(1): 68, 2022 Sep 12.
Article in English | MEDLINE | ID: covidwho-2021289

ABSTRACT

The novel coronavirus disease (COVID-19) pandemic remains a global public health crisis, presenting a broad range of challenges. To help address some of the main problems, the scientific community has designed vaccines, diagnostic tools and therapeutics for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The rapid pace of technology development, especially with regard to vaccines, represents a stunning and historic scientific achievement. Nevertheless, many challenges remain to be overcome, such as improving vaccine and drug treatment efficacies for emergent mutant strains of SARS-CoV-2. Outbreaks of more infectious variants continue to diminish the utility of available vaccines and drugs. Thus, the effectiveness of vaccines and drugs against the most current variants is a primary consideration in the continual analyses of clinical data that supports updated regulatory decisions. The first two vaccines granted Emergency Use Authorizations (EUAs), BNT162b2 and mRNA-1273, still show more than 60% protection efficacy against the most widespread current SARS-CoV-2 variant, Omicron. This variant carries more than 30 mutations in the spike protein, which has largely abrogated the neutralizing effects of therapeutic antibodies. Fortunately, some neutralizing antibodies and antiviral COVID-19 drugs treatments have shown continued clinical benefits. In this review, we provide a framework for understanding the ongoing development efforts for different types of vaccines and therapeutics, including small molecule and antibody drugs. The ripple effects of newly emergent variants, including updates to vaccines and drug repurposing efforts, are summarized. In addition, we summarize the clinical trials supporting the development and distribution of vaccines, small molecule drugs, and therapeutic antibodies with broad-spectrum activity against SARS-CoV-2 strains.


Subject(s)
COVID-19 Drug Treatment , COVID-19 , Viral Vaccines , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , BNT162 Vaccine , COVID-19/prevention & control , Humans , SARS-CoV-2 , Viral Vaccines/therapeutic use
8.
J Biomed Sci ; 29(1): 49, 2022 Jul 07.
Article in English | MEDLINE | ID: covidwho-1923546

ABSTRACT

BACKGROUND: With the continuous emergence of new SARS-CoV-2 variants that feature increased transmission and immune escape, there is an urgent demand for a better vaccine design that will provide broader neutralizing efficacy. METHODS: We report an mRNA-based vaccine using an engineered "hybrid" receptor binding domain (RBD) that contains all 16 point-mutations shown in the currently prevailing Omicron and Delta variants. RESULTS: A booster dose of hybrid vaccine in mice previously immunized with wild-type RBD vaccine induced high titers of broadly neutralizing antibodies against all tested SARS-CoV-2 variants of concern (VOCs). In naïve mice, hybrid vaccine generated strong Omicron-specific neutralizing antibodies as well as low but significant titers against other VOCs. Hybrid vaccine also elicited CD8+/IFN-γ+ T cell responses against a conserved T cell epitope present in wild type and all VOCs. CONCLUSIONS: These results demonstrate that inclusion of different antigenic mutations from various SARS-CoV-2 variants is a feasible approach to develop cross-protective vaccines.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Antibodies, Neutralizing , Antibodies, Viral , Broadly Neutralizing Antibodies , COVID-19/prevention & control , Humans , Mice , SARS-CoV-2/genetics , Vaccines, Synthetic , mRNA Vaccines
9.
Turkish Journal of Computer and Mathematics Education ; 12(6):5125-5128, 2021.
Article in English | ProQuest Central | ID: covidwho-1749749

ABSTRACT

Chat bots are the system or you can say a software that act as a normal person to solve your problems or deal with the situations that you are facing off. So, we are making a project on the bank chat bot. Which will help the users of the bank for doing any tramp. It helps like a real person such as we go to a bank for any help and we contact a person for this. But this bank chat bot will help us instead of a person to solve our worry .So, by remaining in our homes only we can get benefitted. It is a very handy software in nowadays online systems. Due to the COVID-19 people cannot get out so, people can use this initiative to solve their problems that they are facing with their banks. Our chat bot system can do every type of work that a bank can do such withdraw , deposit, knowing about the bank and each item . So it is a most beneficiary thing in our lifestyle.

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