Search

The rapid emergence of multiple strains of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has sparked profound concerns regarding the ongoing evolution of the virus and its potential impact on global health. Classified by the World Health Organization (WHO) as variants of concern (VOC), these strains exhibit heightened transmissibility and pathogenicity, posing significant challenges to existing vaccine strategies. Despite widespread vaccination efforts, the continual evolution of SARS-CoV-2 variants presents a formidable obstacle to achieving herd immunity. Of particular concern is the coronavirus spike (S) protein, a pivotal viral surface protein crucial for host cell entry and infectivity. Mutations within the S protein have been shown to enhance transmissibility and confer resistance to antibody-mediated neutralization, undermining the efficacy of traditional vaccine platforms. Moreover, the S protein undergoes rapid molecular evolution under selective immune pressure, leading to the emergence of diverse variants with distinct mutation profiles. This review underscores the urgent need for vigilance and adaptation in vaccine development efforts to combat the evolving landscape of SARS-CoV-2 mutations and ensure the long-term effectiveness of global immunization campaigns.

OBJECTIVE: To analyze the recommendations issued by the main national and international health organizations regarding anti-COVID-19 vaccination, and define which of them are applicable to the Mexican population based on the predominance of circulating SARS-CoV-2 variants and the current and planned availability of vaccines. MATERIALS AND METHODS: A retrospective observational study was carried out in May 2023, in order to analyze the recommendations established in the objective and define those applicable to the specific context of Mexico. RESULTS Six groups of international and national recommendations for anti-COVID-19 vaccination were located and, after analyzing them, the five recommendations applicable to the Mexican reality described at the end of the document were issued. CONCLUSIONS: Despite the current lower clinical and epidemiological impact of COVID-19, prevention campaigns must be maintained and vaccination patterns optimized especially among populations that have not yet been vaccinated and/or with comorbidities, as well as reinforced health systems, in anticipation of outbreaks of the disease and/or the emergence of SARS-CoV-2 mutations with greater infectivity and/or lethality. The optimization of anti-COVID-19 vaccination in Mexico can be significantly favored through the joint efforts of health authorities and private sector vaccine producers. [ABSTRACT FROM AUTHOR]

Mutation research is crucial for detecting and treating SARS-CoV-2 and developing vaccines. Using over 5,300,000 sequences from SARS-CoV-2 genomes and custom Python programs, we analyzed the mutational landscape of SARS-CoV-2. Although almost every nucleotide in the SARS-CoV-2 genome has mutated at some time, the substantial differences in the frequency and regularity of mutations warrant further examination. C>U mutations are the most common. They are found in the largest number of variants, pangolin lineages, and countries, which indicates that they are a driving force behind the evolution of SARS-CoV-2. Not all SARS-CoV-2 genes have mutated in the same way. Fewer non-synonymous single nucleotide variations are found in genes that encode proteins with a critical role in virus replication than in genes with ancillary roles. Some genes, such as spike (S) and nucleocapsid (N), show more non-synonymous mutations than others. Although the prevalence of mutations in the target regions of COVID-19 diagnostic RT-qPCR tests is generally low, in some cases, such as for some primers that bind to the N gene, it is significant. Therefore, ongoing monitoring of SARS-CoV-2 mutations is crucial. The SARS-CoV-2 Mutation Portal provides access to a database of SARS-CoV-2 mutations. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has impacted the world population adversely, posing a threat to human health. In the past few years, various strains of SARS-CoV-2, each with different mutations in its structure, have impacted human health in negative ways. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mutations influence the virulence, antibody evasion, and Angiotensin-converting enzyme 2 (ACE2) affinity of the virus. These mutations are essential to understanding how a new strain of SARS-CoV-2 has changed and its possible effects on the human body. This review provides an insight into the spike mutations of SARS-CoV-2 variants. As the current scientific data offer a scattered outlook on the various type of mutations, we aimed to categorize the mutations of Beta (B.1.351), Gamma (P.1), Delta (B.1.612.2), and Omicron (B.1.1.529) systematically according to their location in the subunit 1 (S1) and subunit 2 (S2) domains and summarized their consequences as a result. We also compared the miscellany of mutations that have emerged in all four variants to date. The comparison shows that mutations such as D614G and N501Y have emerged in all four variants of concern and that all four variants have multiple mutations within the N-terminal domain (NTD), as in the case of the Delta variant. Other mutations are scattered in the receptor binding domain (RBD) and subdomain 2 (SD2) of the S1 domain. Mutations in RBD or NTD are often associated with antibody evasion. Few mutations lie in the S2 domain in the Beta, Gamma, and Delta variants. However, in the Omicron variant many mutations occupy the S2 domain, hinting towards a much more evasive virus.

Highlights: What are the main findings? Understanding of mutations provides structural insight into SARS-CoV-2 variants; Comparison of mutations narrates the common and different mutations in the variants of concern (VOCs); The SD1-SD2 domain and S2 subunit provides an opportunistic spot for future virulence and vaccine development studies on SARS-CoV-2. What is the significance of the main findings? The SARS-CoV-2 epidemic has paralyzed the healthcare system, shifting the focus of science. It is crucial to comprehend the mutations documented in the Beta (B.1.351), Gamma (P.1), Delta (B.1.612.2), and Omicron (B.1.1.529) variants, which will help us comprehend any future concerns related to COVID 19 and could pave the way for defense strategies against any future variants. The COVID-19 pandemic has impacted the world population adversely, posing a threat to human health. In the past few years, various strains of SARS-CoV-2, each with different mutations in its structure, have impacted human health in negative ways. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mutations influence the virulence, antibody evasion, and Angiotensin-converting enzyme 2 (ACE2) affinity of the virus. These mutations are essential to understanding how a new strain of SARS-CoV-2 has changed and its possible effects on the human body. This review provides an insight into the spike mutations of SARS-CoV-2 variants. As the current scientific data offer a scattered outlook on the various type of mutations, we aimed to categorize the mutations of Beta (B.1.351), Gamma (P.1), Delta (B.1.612.2), and Omicron (B.1.1.529) systematically according to their location in the subunit 1 (S1) and subunit 2 (S2) domains and summarized their consequences as a result. We also compared the miscellany of mutations that have emerged in all four variants to date. The comparison shows that mutations such as D614G and N501Y have emerged in all four variants of concern and that all four variants have multiple mutations within the N-terminal domain (NTD), as in the case of the Delta variant. Other mutations are scattered in the receptor binding domain (RBD) and subdomain 2 (SD2) of the S1 domain. Mutations in RBD or NTD are often associated with antibody evasion. Few mutations lie in the S2 domain in the Beta, Gamma, and Delta variants. However, in the Omicron variant many mutations occupy the S2 domain, hinting towards a much more evasive virus. [ABSTRACT FROM AUTHOR]

The rapid spread of SARS-CoV-2 required immediate actions to control the transmission of the virus and minimize its impact on humanity. An extensive mutation rate of this viral genome contributes to the virus' ability to quickly adapt to environmental changes, impacts transmissibility and antigenicity, and may facilitate immune escape. Therefore, it is of great interest for researchers working in vaccine development and drug design to consider the impact of mutations on virus-drug interactions. Here, we propose a multitarget drug discovery pipeline for identifying potential drug candidates which can efficiently inhibit the Receptor Binding Domain (RBD) of spike glycoproteins from different variants of SARS-CoV-2. Eight homology models of RBDs for selected variants were created and validated using reference crystal structures. We then investigated interactions between host receptor ACE2 and RBDs from nine variants of SARS-CoV-2. It led us to conclude that efficient multi-variant targeting drugs should be capable of blocking residues Q(R)493 and N487 in RBDs. Using methods of molecular docking, molecular mechanics, and molecular dynamics, we identified three lead compounds (hesperidin, narirutin, and neohesperidin) suitable for multitarget SARS-CoV-2 inhibition. These compounds are flavanone glycosides found in citrus fruits – an active ingredient of Traditional Chinese Medicines. The developed pipeline can be further used to (1) model mutants for which crystal structures are not yet available and (2) scan a more extensive library of compounds against other mutated viral proteins. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) have remarkable immunomodulatory properties, low immunogenicity, and paracrine properties as well as the ability to differentiate into multiple cell lines. These properties make them potential candidates for clinical applications in the treatment of neurodegenerative, cardiovascular, and lung diseases, which may be occupational diseases. Preclinical studies using experimental animal models have demonstrated regenerative properties of MSCs in diseases such as silicosis and occupational asthma. Currently, treatment of the novel disease COVID-19 could be enhanced by using MSC therapies. This disease affects many professional groups with great intensity and its consequences might be considered as an occupational disease. It is a significant public health problem and a therapeutic challenge. Despite the development of vaccines against COVID-19, there is growing concern about the emergence of new mutations of the SARS-CoV-2 virus in addition to the known alpha, beta, gamma, and delta variants. There is still no effective COVID-19 treatment and the existing ones only play a supporting role. MSCs offer treatment possibilities as an alternative or complementary therapy. The clinical trials to date using MSCs in patients with COVID-19 give hope for the safe and effective use of this stem cell population. Med Pr. 2021;72(6):693–700

SARS‐CoV‐2 Omicron with its lineages BA.1, BA.2, and BA.3 has triggered a fresh wave of Covid‐19 infections. Though, Omicron has, so far, produced mild symptoms, its genome contains 60 mutations including 37 in the spike protein and 15 in the receptor‐binding domain. Thirteen sites conserved in previous SARS‐CoV‐2 variants carry mutations in Omicron. Many mutations have shown evolution under positive selection. Omicron's giant mutational leap has raised concerns as there are signs of higher virus infectivity rate, pathogenesis, reinfection, and immune evasion. Preliminary studies have reported waning of immunity after two‐dose primary vaccine regime, need for the boosters, folds reduction in vaccine effectiveness and neutralizing antibodies even after boosting and significant neutralization resistance with the therapeutic monoclonal, polyclonal, and convalescent antibodies against Omicron. The narrative that "Omicron is mild," therefore, needs time to be tested with a deeper, scientific dwelling into the facts. [ABSTRACT FROM AUTHOR]

Mutation research is crucial for detecting and treating SARS-CoV-2 and developing vaccines. Using over 5,300,000 sequences from SARS-CoV-2 genomes and custom Python programs, we analyzed the mutational landscape of SARS-CoV-2. Although almost every nucleotide in the SARS-CoV-2 genome has mutated at some time, the substantial differences in the frequency and regularity of mutations warrant further examination. C>U mutations are the most common. They are found in the largest number of variants, pangolin lineages, and countries, which indicates that they are a driving force behind the evolution of SARS-CoV-2. Not all SARS-CoV-2 genes have mutated in the same way. Fewer non-synonymous single nucleotide variations are found in genes that encode proteins with a critical role in virus replication than in genes with ancillary roles. Some genes, such as spike (S) and nucleocapsid (N), show more non-synonymous mutations than others. Although the prevalence of mutations in the target regions of COVID-19 diagnostic RT-qPCR tests is generally low, in some cases, such as for some primers that bind to the N gene, it is significant. Therefore, ongoing monitoring of SARS-CoV-2 mutations is crucial. The SARS-CoV-2 Mutation Portal provides access to a database of SARS-CoV-2 mutations.

Identification of the main SARS-CoV-2 variants in real time is of interest to control the virus and to rapidly devise appropriate public health responses. The RT-qPCR is currently considered to be the reference method to screen SARS-CoV-2 mutations, but it has some limitations. The multiplexing capability is limited when the number of markers to detect increases. Moreover, the performance of this allele-specific method may be impacted in the presence of new mutations. Herein, we present a proof-of-concept study of a simple molecular assay to detect key SARS-CoV-2 mutations. The innovative features of the assay are the multiplex asymmetric one-step RT-PCR amplification covering different regions of SARS-CoV-2 S gene and the visual detection of mutations on a lateral flow DNA microarray. Three kits (Kit 1: N501Y, E484K; Kit 2: L452R, E484K/Q; Kit 3: K417N, L452R, E484K/Q/A) were developed to match recommendations for surveillance of SARS-CoV-2 variants between January and December 2021. The clinical performance was assessed using RNA extracts from 113 SARS-CoV-2-positive samples with cycle thresholds <30, and results demonstrated that our assay allows specific and sensitive detection of mutations, with a performance comparable to that of RT-qPCR. The VARCoV assay detected four SARS-CoV-2 targets and achieved specific and sensitive screening of spike mutations associated with the main variants of concern, with a performance comparable to that of RT-qPCR. With well-defined virus sequences, this assay can be rapidly adapted to other emerging mutations; it is a promising tool for variant surveillance. [ABSTRACT FROM AUTHOR]

This issue of the Biomedical Journal tells us about the risks of electronic cigarette smoking, variations of SARS-CoV-2 and ACE2, and how COVID-19 affects the gastrointestinal system. Moreover, we learn that cancer immunotherapy seems to work well in elderly patients, how thyroid hormones regulate noncoding RNAs in a liver tumour context, and that G6PD is a double-edged sword of redox signalling. We also discover that Perilla leaf extract could inhibit SARS-CoV-2, that artificial neural networks can diagnose COVID-19 patients and predict vaccine epitopes on the Epstein–Barr Virus, and that men and women have differential inflammatory responses to physical effort. Finally, the surgical strategies for drug-resistant epilepsy, computer-supervised double-jaw surgery, dental pulp stem cell motility, and the restitution of the brain blood supply after atherosclerotic stroke are discussed.

Identification of the main SARS-CoV-2 variants in real time is of interest to control the virus and to rapidly devise appropriate public health responses. The RT-qPCR is currently considered to be the reference method to screen SARS-CoV-2 mutations, but it has some limitations. The multiplexing capability is limited when the number of markers to detect increases. Moreover, the performance of this allele-specific method may be impacted in the presence of new mutations. Herein, we present a proof-of-concept study of a simple molecular assay to detect key SARS-CoV-2 mutations. The innovative features of the assay are the multiplex asymmetric one-step RT-PCR amplification covering different regions of SARS-CoV-2 S gene and the visual detection of mutations on a lateral flow DNA microarray. Three kits (Kit 1: N501Y, E484K; Kit 2: L452R, E484K/Q; Kit 3: K417N, L452R, E484K/Q/A) were developed to match recommendations for surveillance of SARS-CoV-2 variants between January and December 2021. The clinical performance was assessed using RNA extracts from 113 SARS-CoV-2-positive samples with cycle thresholds

Since early 2020, coronavirus diseases 2019 (COVID‐19) infection pandemic/endemic is constantly surprising health experts because of continuous variations in the structures of severe acute respiratory coronavirus 2 (SARS‐CoV‐2) in the form of newly emerged variants. Such mutations have exhibited high mortality and severity due to the newly emerged more infectious sites of SARS‐CoV‐2, making viral infection more transmissible, infectious, and severe. Recently, SARS‐CoV‐2 mutated to another variant, namely, Omicron (B.1.1.529), which is many times more transmissible and infectious than existed deadly Delta variants of the virus. This severity is closely correlated to a larger number of mutations observed in the receptor‐binding domain of the spike protein of the Omicron‐SARS‐CoV‐2. Considering severity, Omicron has been declared as variant of concerns by the World Health Organization and within days from its emergence, Omicron infection has spread globally, increased hospitalization, exhibited more severity for the young generation, invaded defense mechanism of natural immunity, not responsive to the available vaccines. Such circumstances resonated with the efficiency of available strategies established to manage COVID‐19 intelligently and successfully. To explore these aspects, this perspective article carefully and critically summarizes the Omicron's origin, structure, pathogenesis, impact health along with health systems, and experts' recommendations to manage it successfully. [ABSTRACT FROM AUTHOR]

The knowledge of SARS-CoV-2 proteome variations is important to understand its evolutionary tactics and to design drug/vaccine. An extensive analysis of 125,746 whole proteome reveals 7915 recurring mutations (involving 5146 positions) during December 2019-November 2020. Among these, 10 and 51 are highly and moderately recurring mutations respectively. Ever since the pandemic outbreak, ∼50% new proteome variants evolve every month, resulting in 5 major clades. Intriguingly, ∼70% of the variants reported in January 2020 are due to the emergence of mutations, which sharply declines to ∼40% in April 2020 and thenceforth, declines steadily till November 2020 (∼10%). An exactly opposite trend is seen for variants evolved with a cocktail of existing mutations: the lowest in January 2020 (∼20%) and the highest in November 2020 (80%). This leads to a steady increase in the average number of mutations per sequence. This indicates that the virus has reached the slow pace to accept new mutations. Instead, it uses a mutation combination strategy for survival.

Abstract Since early 2020, coronavirus diseases 2019 (COVID‐19) infection pandemic/endemic is constantly surprising health experts because of continuous variations in the structures of severe acute respiratory coronavirus 2 (SARS‐CoV‐2) in the form of newly emerged variants. Such mutations have exhibited high mortality and severity due to the newly emerged more infectious sites of SARS‐CoV‐2, making viral infection more transmissible, infectious, and severe. Recently, SARS‐CoV‐2 mutated to another variant, namely, Omicron (B.1.1.529), which is many times more transmissible and infectious than existed deadly Delta variants of the virus. This severity is closely correlated to a larger number of mutations observed in the receptor‐binding domain of the spike protein of the Omicron‐SARS‐CoV‐2. Considering severity, Omicron has been declared as variant of concerns by the World Health Organization and within days from its emergence, Omicron infection has spread globally, increased hospitalization, exhibited more severity for the young generation, invaded defense mechanism of natural immunity, not responsive to the available vaccines. Such circumstances resonated with the efficiency of available strategies established to manage COVID‐19 intelligently and successfully. To explore these aspects, this perspective article carefully and critically summarizes the Omicron's origin, structure, pathogenesis, impact health along with health systems, and experts’ recommendations to manage it successfully.

A continual rise in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection causing coronavirus disease (COVID-19) has become a global threat. The main problem comes when SARS-CoV-2 gets mutated with the rising infection and becomes more lethal for humankind than ever. Mutations in the structural proteins of SARS-CoV-2, i.e., the spike surface glycoprotein (S), envelope (E), membrane (M) and nucleocapsid (N), and replication machinery enzymes, i.e., main protease (Mpro) and RNA-dependent RNA polymerase (RdRp) creating more complexities towards pathogenesis and the available COVID-19 therapeutic strategies. This study analyzes how a minimal variation in these enzymes, especially in S protein at the genomic/proteomic level, affects pathogenesis. The structural variations are discussed in light of the failure of small molecule development in COVID-19 therapeutic strategies. We have performed in-depth sequence- and structure-based analyses of these proteins to get deeper insights into the mechanism of pathogenesis, structure-function relationships, and development of modern therapeutic approaches. Structural and functional consequences of the selected mutations on these proteins and their association with SARS-CoV-2 virulency and human health are discussed in detail in the light of our comparative genomics analysis. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 infectivity is largely determined by the virus Spike protein binding to the ACE2 receptor. Meanwhile, marked infection rate differences were reported between populations and individuals. To understand the disease dynamic, we developed a computational approach to study the implications of both SARS-CoV-2 RBD mutations and ACE2 polymorphism on the stability of the virus-receptor complex. We used the 6LZG PDB RBD/ACE2 3D model, the mCSM platform, the LigPlot+ and PyMol software to analyze the data on SARS-CoV-2 mutations and ACE variants retrieved from GISAID and Ensembl/GnomAD repository. We observed that out of 351 RBD point mutations, 83% destabilizes the complex according to free energy (ΔΔG) differences. We also spotted variations in the patterns of polar and hydrophobic interactions between the mutations occurring in 15 out of 18 contact residues. Similarly, comparison of the effect on the complex stability of different ACE2 variants showed that the pattern of molecular interactions and the complex stability varies also according to ACE2 polymorphism. We infer that it is important to consider both ACE2 variants and circulating SARS-CoV-2 RBD mutations to assess the stability of the virus-receptor association and evaluate infectivity. This approach might offers a good molecular ground to mitigate the virus spreading. [ABSTRACT FROM AUTHOR]

A continual rise in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection causing coronavirus disease (COVID-19) has become a global threat. The main problem comes when SARS-CoV-2 gets mutated with the rising infection and becomes more lethal for humankind than ever. Mutations in the structural proteins of SARS-CoV-2, i.e., the spike surface glycoprotein (S), envelope (E), membrane (M) and nucleocapsid (N), and replication machinery enzymes, i.e., main protease (Mpro) and RNA-dependent RNA polymerase (RdRp) creating more complexities towards pathogenesis and the available COVID-19 therapeutic strategies. This study analyzes how a minimal variation in these enzymes, especially in S protein at the genomic/proteomic level, affects pathogenesis. The structural variations are discussed in light of the failure of small molecule development in COVID-19 therapeutic strategies. We have performed in-depth sequence- and structure-based analyses of these proteins to get deeper insights into the mechanism of pathogenesis, structure-function relationships, and development of modern therapeutic approaches. Structural and functional consequences of the selected mutations on these proteins and their association with SARS-CoV-2 virulency and human health are discussed in detail in the light of our comparative genomics analysis.

The rapid spread of SARS-CoV-2 required immediate actions to control the transmission of the virus and minimize its impact on humanity. An extensive mutation rate of this viral genome contributes to the virus’ ability to quickly adapt to environmental changes, impacts transmissibility and antigenicity, and may facilitate immune escape. Therefore, it is of great interest for researchers working in vaccine development and drug design to consider the impact of mutations on virus-drug interactions. Here, we propose a multitarget drug discovery pipeline for identifying potential drug candidates which can efficiently inhibit the Receptor Binding Domain (RBD) of spike glycoproteins from different variants of SARS-CoV-2. Eight homology models of RBDs for selected variants were created and validated using reference crystal structures. We then investigated interactions between host receptor ACE2 and RBDs from nine variants of SARS-CoV-2. It led us to conclude that efficient multi-variant targeting drugs should be capable of blocking residues Q(R)493 and N487 in RBDs. Using methods of molecular docking, molecular mechanics, and molecular dynamics, we identified three lead compounds (hesperidin, narirutin, and neohesperidin) suitable for multitarget SARS-CoV-2 inhibition. These compounds are flavanone glycosides found in citrus fruits – an active ingredient of Traditional Chinese Medicines. The developed pipeline can be further used to (1) model mutants for which crystal structures are not yet available and (2) scan a more extensive library of compounds against other mutated viral proteins.

BackgroundSeveral variants of the SARS-CoV-2 have been documented globally during the current COVID-19 pandemic. The N501Y, 69-70del, K417N, and E484K SARS-CoV-2 mutations have been documented among the most relevant due to their potential pathogenic biological effects. This study aimed to design, validate, and propose a fast real-time RT-qPCR assay to detect SARS-CoV-2 mutations with possible clinical and epidemiological relevance in the Mexican population.MethodsTargeting spike (S) gene mutations of SARS-CoV-2 (N501Y, 69-70del, K417N, and E484K), specific primers, and probes for three specific quantitative reverse transcription PCR (RT-qPCR) assays were designed, and validated using Sanger sequencing. These assays were applied in clinical samples of 1060 COVID-19 patients from Jalisco Mexico.ResultsIn silico analyzes showed high specificity of the three assays. Amplicons of samples were confirmed through sequencing. The screening of samples of COVID-19 patients allowed the identification of the E484K mutation in nine individuals and the identification of P.2 Brazilian variant in Mexico.ConclusionThis work provides low-cost RT-qPCR assays for rapid screening and molecular surveillance of mutations with potential clinical impact. This strategy allowed the detection of E484K mutation and P.2 variant for the first time in samples from the Mexican population.

Background: Several variants of the SARS-CoV-2 have been documented globally during the current COVID-19 pandemic. The N501Y, 69-70del, K417N, and E484K SARS-CoV-2 mutations have been documented among the most relevant due to their potential pathogenic biological effects. This study aimed to design, validate, and propose a fast real-time RT-qPCR assay to detect SARS-CoV-2 mutations with possible clinical and epidemiological relevance in the Mexican population. Methods: Targeting spike (S) gene mutations of SARS-CoV-2 (N501Y, 69-70del, K417N, and E484K), specific primers, and probes for three specific quantitative reverse transcription PCR (RT-qPCR) assays were designed, and validated using Sanger sequencing. These assays were applied in clinical samples of 1060 COVID-19 patients from Jalisco Mexico. Results: In silico analyzes showed high specificity of the three assays. Amplicons of samples were confirmed through sequencing. The screening of samples of COVID-19 patients allowed the identification of the E484K mutation in nine individuals and the identification of P.2 Brazilian variant in Mexico. Conclusion: This work provides low-cost RT-qPCR assays for rapid screening and molecular surveillance of mutations with potential clinical impact. This strategy allowed the detection of E484K mutation and P.2 variant for the first time in samples from the Mexican population. [ABSTRACT FROM AUTHOR]

The rapid emergence of multiple strains of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has sparked profound concerns regarding the ongoing evolution of the virus and its potential impact on global health. Classified by the World Health Organization (WHO) as variants of concern (VOC), these strains exhibit heightened transmissibility and pathogenicity, posing significant challenges to existing vaccine strategies. Despite widespread vaccination efforts, the continual evolution of SARS-CoV-2 variants presents a formidable obstacle to achieving herd immunity. Of particular concern is the coronavirus spike (S) protein, a pivotal viral surface protein crucial for host cell entry and infectivity. Mutations within the S protein have been shown to enhance transmissibility and confer resistance to antibody-mediated neutralization, undermining the efficacy of traditional vaccine platforms. Moreover, the S protein undergoes rapid molecular evolution under selective immune pressure, leading to the emergence of diverse variants with distinct mutation profiles. This review underscores the urgent need for vigilance and adaptation in vaccine development efforts to combat the evolving landscape of SARS-CoV-2 mutations and ensure the long-term effectiveness of global immunization campaigns., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

[Display omitted] • A fluorescent approach was developed for the detection of SARS-CoV-2 mutations. • L-EXPAR was used for first round signal amplification. • PS-SPA was employed to further amplified the detection signal. • The detection limit of SARS-CoV-2 mutation is 1 fM. • The platform provides portable, cost-effective, and direct mutation detection. In this work, we developed a programmable mutation detection platform with a dual amplification strategy for universal detection of SARS-CoV-2 mutations based on ligation-triggered isothermal exponential amplification reaction(L-EXPAR) and phosphorothioate modified self-priming amplification (PS-SPA). In the presence of mutant target (MT) sequence, it complements with hairpin probe (H1) and hairpin probe (H2) and triggered L-EXPAR at lower temperature. A large number of single-strand DNA (ssDNA) is produced in the circle of ligation, nicking, polymerization, and strand displacement. The ssDNA products containing target sequences can feed back and initiate another L-EXPAR. The ligated H1-H2 complex triggers another isothermal process termed PS-PSA at higher temperature. 20 bases of H1-H2 complex on the 5′ end modified with PS can form a short stem-loop hairpin due to the lower Tm of PS modification. The resulting overhanging 3′ end can also fold back as a new primer to initiate the next round of polymerization. In the circle of PS-SPA, the H1-H2 chain can be extended to be a long hairpin concatemer containing a great number of tandem target sequences. The resulting DNA products can be monitored in real-time fluorescent signaling. In the presence of the SARS-CoV-2 wild type (WT) sequence, the ligation between H1 and H2 cannot happen due to the mismatch of the last base on the 3′ end of H1. The proposed assay displayed a good linear range from 1 fM to 1 nM with a detection limit of femtomole level for the detection of SARS-CoV-2 spike gene D614G mutation and Del246-252 + D253N deletion. [ABSTRACT FROM AUTHOR]

Considering the lack of effective treatments against COVID-19, wastewater-based epidemiology (WBE) is emerging as a cost-effective approach for real-time population-wide SARS-CoV-2 monitoring. Here, we report novel molecular assays for sensitive detection and mutational/variant analysis of SARS-CoV-2 in wastewater. Highly stable regions of SARS-CoV-2 RNA were identified by RNA stability analysis and targeted for the development of novel nested PCR assays. Targeted DNA sequencing (DNA-seq) was applied for the analysis and quantification of SARS-CoV-2 mutations/variants, following hexamers-based reverse transcription and nested PCR-based amplification of targeted regions. Three-dimensional (3D) structure models were generated to examine the predicted structural modification caused by genomic variants. WBE of SARS-CoV-2 revealed to be assay dependent, and significantly improved sensitivity achieved by assay combination (94%) vs. single-assay screening (30%–60%). Targeted DNA-seq allowed the quantification of SARS-CoV-2 mutations/variants in wastewater, which agreed with COVID-19 patients’ sequencing data. A mutational analysis indicated the prevalence of D614G (S) and P323L (RdRP) variants, as well as of the Β.1.1.7/alpha variant of concern, in agreement with the frequency of Β.1.1.7/alpha variant in clinical samples of the same period of the third pandemic wave at the national level. Our assays provide an innovative cost-effective platform for real-time monitoring and early-identification of SARS-CoV-2 variants at community/population levels.

The aim is to recommend a fast and cost-effective screening procedure for UK/SA SARS-CoV-2 variants in a routing diagnostic setting. A rapid procedure using qPCR is described to provide clinicians with information about the two currently most prevalent variants (B1.1.7 and B1.351) that harbour receptor binding domain mutation N501Y. The N501Y specific assay only delivers an amplification signal if the Y501 variant is present. 436 samples initially screened positive for SARS-CoV-2 were randomly selected. Only one of these samples showed a fluorescence signal increase indicative for the Y501 variant. The remaining 435 samples had a melting peak at 54 °C indicating the N501 wildtype. The screening of a broad population base can still be performed with the established test system. In case of a positive test for SARS-CoV-2 and corresponding clinical and anamnestic indications, a second qPCR for the mutation N501Y can follow and deliver the result to public health authorities and to the treating physician within a few hours. [ABSTRACT FROM AUTHOR]

The SARS-CoV-2 is an RNA-based virus and the most vital step of its survival is the attachment to hACE2 through its spike protein. Although SARS-CoV-2 has the ability to maintain high accurate replication and it can be accepted as a low mutation risked virus, it already showed more than nine thousand mutations in spike protein, of which 44 mutations are located within a 3.2 Å interacting distance from the hACE2 receptor. Mutations on spike protein, N501Y and N501T raised serious concerns for higher transmissibility and resistance towards current vaccines. In the current study, the mutational outcomes of N501Y and N501T on the hACE2-SARS CoV-2 spike protein complexation were analyzed by employing all-atom classic molecular dynamics (MD) simulations. These simulations revealed that both N501Y and N501T mutations increased the binding strength of spike protein to the host hACE2, predicted by binding free energy analysis via MM/GBSA rescoring scheme. This study highlights the importance of energy-based analysis for identifying mutational outcomes and will shed light on handling long-term and effective treatment strategies including repurposing anti-viral drugs, anti -SARS-CoV-2 antibodies, vaccines, and antisense based-therapies. [Display omitted] • Classical all-atom MD simulations on human ACE2 bound WT, N501Y, and N501T mutant SARS CoV-2 spike proteins were performed. • Two novel N501Y and N501T mutations on hACE2-SARS CoV-2 spike protein complex structure were analyzed via energy-based approach. • Binding free energy of hACE2-SARS CoV-2 spike protein increased upon N501T and N501Y mutations, compared to the WT protein. • Formation of aromatic pocket around Tyr 501 leads to stronger binding for N501Y mutant SARS-CoV-2 virus to hACE2. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 has mutated many times among different populations. We analyzed wild-type spike protein and 18 different variants of SARS-CoV-2 spike protein known until the beginning of 2022 (alpha, beta, B.1.429, B.1.616, B.1.620, B.1.617.3, C.1.2, delta, epsilon, eta, gamma, iota, kappa, lambda, mu, omicron, theta, and zeta) for their interaction with 16 phytocompounds and remdesivir, resulting into 425 combinations. The largest number of mutations has been reported in the omicron followed by delta variant. However, the virulence of the delta variant has been reported higher as compared to omicron. Mutations at a few locations (D215G, K417N, E484K, N501Y, D614G, and P681H) were common in most of the variants. 3 D structures of all the 18 spike proteins were created using SWISS-MODEL to test the binding affinities with caffeine theophylline, emodin, vitexin, berberine, curcumin, piperine, quercetin, artemisinin, carvacrol, capsaicin, tetrahydrocannabinol, cannabidiol, α- pinene, β- pinene and gingerol. Phytocompounds and mutant variants were prepared using AutoDock 4.2.6 software. Binding affinities of the selected phytocompounds with the different mutant spike proteins were achieved using AutoDock Vina. Out of all combinations investigated, the best binding affinities were observed with 3 variants of SAR-CoV-2 with 5 phytocompounds along with remdesivir. The range of best binding energies varied from -9.1 to -8.0 kcal/mol. Further, MD simulation was done for selected 9 phytocompound-spike mutant complexes for analyzing the stability of interactions for 100 ns. ADMET studies via ProTox-II and SwissADME displayed that phytocompounds are safe and less toxic in comparison to remdesivir.Communicated by Ramaswamy H. Sarma.

Considering the lack of effective treatments against COVID-19, wastewater-based epidemiology (WBE) is emerging as a cost-effective approach for real-time population-wide SARS-CoV-2 monitoring. Here, we report novel molecular assays for sensitive detection and mutational/variant analysis of SARS-CoV-2 in wastewater. Highly stable regions of SARS-CoV-2 RNA were identified by RNA stability analysis and targeted for the development of novel nested PCR assays. Targeted DNA sequencing (DNA-seq) was applied for the analysis and quantification of SARS-CoV-2 mutations/variants, following hexamers-based reverse transcription and nested PCR-based amplification of targeted regions. Three-dimensional (3D) structure models were generated to examine the predicted structural modification caused by genomic variants. WBE of SARS-CoV-2 revealed to be assay dependent, and significantly improved sensitivity achieved by assay combination (94%) vs. single-assay screening (30%–60%). Targeted DNA-seq allowed the quantification of SARS-CoV-2 mutations/variants in wastewater, which agreed with COVID-19 patients' sequencing data. A mutational analysis indicated the prevalence of D614G (S) and P323L (RdRP) variants, as well as of the Β.1.1.7/alpha variant of concern, in agreement with the frequency of Β.1.1.7/alpha variant in clinical samples of the same period of the third pandemic wave at the national level. Our assays provide an innovative cost-effective platform for real-time monitoring and early-identification of SARS-CoV-2 variants at community/population levels. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) have remarkable immunomodulatory properties, low immunogenicity, and paracrine properties as well as the ability to differentiate into multiple cell lines. These properties make them potential candidates for clinical applications in the treatment of neurodegenerative, cardiovascular, and lung diseases, which may be occupational diseases. Preclinical studies using experimental animal models have demonstrated regenerative properties of MSCs in diseases such as silicosis and occupational asthma. Currently, treatment of the novel disease COVID-19 could be enhanced by using MSC therapies. This disease affects many professional groups with great intensity and its consequences might be considered as an occupational disease. It is a significant public health problem and a therapeutic challenge. Despite the development of vaccines against COVID-19, there is growing concern about the emergence of new mutations of the SARS-CoV-2 virus in addition to the known alpha, beta, gamma, and delta variants. There is still no effective COVID-19 treatment and the existing ones only play a supporting role. MSCs offer treatment possibilities as an alternative or complementary therapy. The clinical trials to date using MSCs in patients with COVID-19 give hope for the safe and effective use of this stem cell population. Med Pr. 2021;72(6):693-700., (This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.)

This issue of the Biomedical Journal tells us about the risks of electronic cigarette smoking, variations of SARS-CoV-2 and ACE2, and how COVID-19 affects the gastrointestinal system. Moreover, we learn that cancer immunotherapy seems to work well in elderly patients, how thyroid hormones regulate noncoding RNAs in a liver tumour context, and that G6PD is a double-edged sword of redox signalling. We also discover that Perilla leaf extract could inhibit SARS-CoV-2, that artificial neural networks can diagnose COVID-19 patients and predict vaccine epitopes on the Epstein-Barr Virus, and that men and women have differential inflammatory responses to physical effort. Finally, the surgical strategies for drug-resistant epilepsy, computer-supervised double-jaw surgery, dental pulp stem cell motility, and the restitution of the brain blood supply after atherosclerotic stroke are discussed., (Copyright © 2021 Chang Gung University. Published by Elsevier B.V. All rights reserved.)

The knowledge about SARS-CoV-2 proteome variations is important to understand its evolutionary tactics and in drug/vaccine design. An extensive analysis of 125,747 whole proteome reveals 7915 recurring mutations (involving 5146 positions) during December2019-November 2020. Among these, 10 and 51 are highly and moderately recurring mutations respectively. Ever since the pandemic outbreak, ∼50% new proteome variants evolve every month, resulting in 5 major clades. Intriguingly, ∼70% of the variants reported in January 2020 are due to the emergence of new mutations, which sharply declines to ∼ 40% in April 2020 and thenceforth, declines steadily till November 2020(∼10%). An exactly opposite trend is seen for variants evolved with cocktail of existing mutations: the lowest in January 2020(∼20%) and the highest in November 2020(80%). This leads to a steady increase in the average number of mutations per sequence. This indicates that the virus has reached the slow pace to accept new mutations. Instead, it uses a mutation combination strategy for survival., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)