Wide Range Of Viral Pathogens Research Articles

HEX17(Neumifil): An intranasal respiratory biotherapeutic with broad-acting antiviral activity

Broad-acting antiviral strategies to prevent respiratory tract infections are urgently required. Emerging or re-emerging viral diseases caused by new or genetic variants of viruses such as influenza viruses (IFVs), respiratory syncytial viruses (RSVs), human rhinoviruses (HRVs), parainfluenza viruses (PIVs) or coronaviruses (CoVs), pose a severe threat to human health, particularly in the very young or old, or in those with pre-existing respiratory conditions such as asthma or chronic obstructive pulmonary disease (COPD). Although vaccines remain a key component in controlling and preventing viral infections, they are unable to provide broad-spectrum protection against recurring seasonal infections or newly emerging threats. HEX17 (aka Neumifil), is a first-in-class protein-based antiviral prophylactic for respiratory viral infections. HEX17 consists of a hexavalent carbohydrate-binding module (CBM) with high affinity to sialic acids, which are typically present on terminating branches of glycans on viral cellular receptors. This allows HEX17 to block virus engagement of host receptors and inhibit infection of a wide range of viral pathogens and their variants with reduced risk of antiviral resistance. As described herein, HEX17 has demonstrated broad-spectrum efficacy against respiratory viral pathogens including IFV, RSV, CoV and HRV in multiple in vivo and in vitro studies. In addition, HEX17 can be easily administered via an intranasal spray and is currently undergoing clinical trials.

Regional European genetic ancestry predicts type I interferon level and risk of severe viral infection.

Viral infection outcomes vary widely between individuals, ranging from mild symptoms to severe organ failure and death, and it is clear that host genetic factors play a role in this variability. Type I interferon (IFN) is a critical anti-viral cytokine, and we have previously noted differences in type I IFN levels between world populations. In this study, we investigate the interrelationship between regional European genetic ancestry, type I IFN levels and severe viral infection outcomes. In cohorts of European ancestry lupus patients living in Europe, we noted higher IFN in the Northwestern populations as compared to Southeastern populations. In an independent cohort of European ancestry lupus patients from the USA with varying proportional regional European genetic admixture, we observed the same Northwest vs. Southeast European ancestry IFN gradient. We developed a model to predict type I IFN level based on regional European ancestry (Area under the curve (AUC) = 0.73, P = 6.1e-6). Examining large databases containing serious viral outcomes data, we found that lower predicted IFN in the corresponding European country was significantly correlated with increased viral infection fatality rate, including Coronavirus Disease 2019 (COVID-19), viral hepatitis and HIV [correlation coefficients: -0.79 (P = 4e-2), -0.94 (P = 6e-3) and -0.96 (P = 8e-2), respectively]. This association between predicted type I IFN level and viral outcome severity suggests a potential causal relationship, as greater intrinsic type I IFN is beneficial in host defense against viruses. Genetic testing could provide insight into individual and population level risk of fatality due to viruses prior to infection, across a wide range of viral pathogens.

Unlocking the Viral Universe: Metagenomic Analysis of Bat Samples Using Next-Generation Sequencing.

Next-generation sequencing technologies have revolutionized the field of virology by enabling the reading of complete viral genomes, extensive metagenomic studies, and the identification of novel viral pathogens. Although metagenomic sequencing has the advantage of not requiring specific probes or primers, it faces significant challenges in analyzing data and identifying novel viruses. Traditional bioinformatics tools for sequence identification mainly depend on homology-based strategies, which may not allow the detection of a virus significantly different from known variants due to the extensive genetic diversity and rapid evolution of viruses. In this work, we performed metagenomic analysis of bat feces from different Russian cities and identified a wide range of viral pathogens. We then selected sequences with minimal homology to a known picornavirus and used "Switching Mechanism at the 5' end of RNA Template" technology to obtain a longer genome fragment, allowing for more reliable identification. This study emphasizes the importance of integrating advanced computational methods with experimental strategies for identifying unknown viruses to better understand the viral universe.

Multiplex polymerase chain reaction method for the diagnosis of unspecified viral acute gastroenteritis

Acute gastroenteritis (AG) can be caused by a wide range of viral pathogens. Detection of dominant pathogens (noro-, rota-, adeno-, enteroviruses) makes it possible to establish the etiology of 40-60% of AG cases. To increase the proportion of their etiological interpretation, it is advisable to conduct research on minor intestinal viruses. This article presents the method of multiplex polymerase chain reaction for the diagnosis of unspecified viral intestinal infection. It allows detecting the genetic material of astro-, sapo-, parecho-, boka-, picobirna- and aichi viruses in biological material (faeces). The approbation of the method made it possible to detect the presence of these pathogens in 4,89% of patients with AG, in whose biological material were no dominant intestinal viruses.

NATURAL ANTIVIRALS FOR THE MANAGEMENT OF SARS-COVID-19: A REVIEW

Unlike previous outbreaks like SARS and MERS, caused by corona family viruses, COVID-19 became a much worse worldwide pandemic. SARS CoV-2, another coronavirus, causes it. Finding effective therapeutics against this global health crisis became a significant challenge for researchers. However, Allopathic medicine is effective to some extent with severe side effects, which cause concern. In this process, some researchers focused on natural compounds like plant-synthesized secondary metabolites (PSMs) for the treatment of COVID-19. Because these natural compounds like PSMs had a history of tackling a wide range of viral pathogens successfully without significant side effects. Many medicinal plants from different families have antiviral activities. This review intends to systematically evaluate the natural metabolites that could be used against this new disease looking at their natural sources, mechanism of action, and previous pharmacological usages. So, it can be a good initiation for the greater goal of finding effective natural therapeutics for the treatment of Covid-19 without any severe side effects.

Label-Free Electrochemical Biosensors for the Determination of Flaviviruses: Dengue, Zika, and Japanese Encephalitis.

A highly effective way to improve prognosis of viral infectious diseases and to determine the outcome of infection is early, fast, simple, and efficient diagnosis of viral pathogens in biological fluids. Among a wide range of viral pathogens, Flaviviruses attract a special attention. Flavivirus genus includes more than 70 viruses, the most familiar being dengue virus (DENV), Zika virus (ZIKV), and Japanese encephalitis virus (JEV). Haemorrhagic and encephalitis diseases are the most common severe consequences of flaviviral infection. Currently, increasing attention is being paid to the development of electrochemical immunological methods for the determination of Flaviviruses. This review critically compares and evaluates recent research progress in electrochemical biosensing of DENV, ZIKV, and JEV without labelling. Specific attention is paid to comparison of detection strategies, electrode materials, and analytical characteristics. The potential of so far developed biosensors is discussed together with an outlook for further development in this field.

Plants Metabolites: Possibility of Natural Therapeutics Against the COVID-19 Pandemic.

COVID-19, a disease induced by SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2), has been the cause of a worldwide pandemic. Though extensive research works have been reported in recent days on the development of effective therapeutics against this global health crisis, there is still no approved therapy against SARS-CoV-2. In the present study, plant-synthesized secondary metabolites (PSMs) have been prioritized to make a review focusing on the efficacy of plant-originated therapeutics for the treatment of COVID-19. Plant metabolites are a source of countless medicinal compounds, while the diversity of multidimensional chemical structures has made them superior to treat serious diseases. Some have already been reported as promising alternative medicines and lead compounds for drug repurposing and discovery. The versatility of secondary metabolites may provide novel antibiotics to tackle MDR (Multi-Drug Resistant) microbes too. This review attempted to find out plant metabolites that have the therapeutic potential to treat a wide range of viral pathogens. The study includes the search of remedies belonging to plant families, susceptible viral candidates, antiviral assays, and the mode of therapeutic action; this attempt resulted in the collection of an enormous number of natural therapeutics that might be suggested for the treatment of COVID-19. About 219 plants from 83 families were found to have antiviral activity. Among them, 149 plants from 71 families were screened for the identification of the major plant secondary metabolites (PSMs) that might be effective for this pandemic. Our investigation revealed that the proposed plant metabolites can serve as potential anti- SARS-CoV-2 lead molecules for further optimization and drug development processes to combat COVID-19 and future pandemics caused by viruses. This review will stimulate further analysis by the scientific community and boost antiviral plant-based research followed by novel drug designing.

Association of HSV reactivation and pro-inflammatory cytokine levels with the severity of stomatitis after BEAM chemotherapy and autologous SCT

Stomatitis, including oral mucositis and ulcerations induced by HSV-reactivation are major sources of morbidity after high-dose (HD) chemotherapy and subsequent autologous hematopoietic stem cell transplantation (SCT). While increased synthesis of pro-inflammatory cytokines, such as interleukin-1 (IL-1) and tumor necrosis factor alpha (TNF-α)-as well as reactivation of viral infections have frequently been observed in this setting, data on their association with the severity of mucositis is limited. Fifteen patients with Hodgkin's or non-Hodgkin's lymphoma receiving HD conditioning chemotherapy and autologous SCT were assessed with respect to oral pain and severity of stomatitis on day -6, 0, +5 to +7, +13 to +15, and +100. On the same dates, IL-1 and TNF-α were quantified in saliva and screening for a wide range of viral pathogens was carried out by cell culture and PCR and complemented by serological analyses. t Tests were used to assess potential associations between these variables. All but one patient had a positive HSV IgG titer at baseline. Reactivation as confirmed by HSV PCR was observed in seven patients (50%). There was a significant association between the presence of HSV in saliva samples and severity of stomatitis (t test, p = 0.015). The highest concentration of TNF-α and IL-1 coincided with the maximum intensity of stomatitis, but the association was not significant. We found a significant association between the presence of HSV in saliva samples and severity of stomatitis in patients receiving HD chemotherapy and subsequent autologous SCT. While acyclovir prophylaxis has become standard for patients undergoing allogeneic SCT, this issue has not been sufficiently explored for other chemotherapy regimens. Based on our findings, conduction of a well-powered controlled randomized trial may be warranted.

Phosphorothioate-Modified Oligodeoxynucleotides Inhibit Human Cytomegalovirus Replication by Blocking Virus Entry

Studies in animal models have provided evidence that Toll-like receptor 9 (TLR9) agonists, such as synthetic oligodeoxynucleotides (ODNs) that contain immunostimulatory deoxycytidyl-deoxyguanosine (CpG) motifs (CpG ODNs), protect against a wide range of viral pathogens. This antiviral activity has been suggested to be indirect and secondary to CpG-induced cytokines and inflammatory responses triggered through TLR9 activation. However, few studies have addressed the potential of CpG ODNs as direct antiviral agents. Here, we report on the ability of some CpG ODNs to directly suppress, almost completely, human cytomegalovirus (HCMV) replication in both primary fibroblasts and endothelial cells. Murine CMV replication was inhibited as well, whereas no inhibition was observed for herpes simplex virus type 1, adenovirus, or vesicular stomatitis virus. The antiviral activity of these ODNs was significantly reduced when they were added after virus adsorption, indicating that their action may be primarily targeted to the very early phases of the HCMV cycle. In fact, the B-class prototype CpG ODN 2006 effectively prevented the nuclear localization of pp65 and input viral DNA, which suggests that it inhibits HCMV entry. Moreover, a CpG 2006 control, ODN 2137 without CpG motifs, also showed a potent inhibitory activity on the HCMV entry phase, indicating that the anticytomegaloviral activity is independent of the CpG motif. In contrast, a phosphodiester version of CpG 2006 showed reduced antiviral activity, indicating that the inhibitory activity is dependent on the phosphorothioate backbone of the ODN. These results suggest that this yet-unrecognized activity of CpG ODNs may be of interest in the development of novel anticytomegaloviral molecules.

Adding the Third Dimension to Virus Life Cycles: Three-Dimensional Reconstruction of Icosahedral Viruses from Cryo-Electron Micrographs

Viruses are cellular parasites. The linkage between viral and host functions makes the study of a viral life cycle an important key to cellular functions. A deeper understanding of many aspects of viral life cycles has emerged from coordinated molecular and structural studies carried out with a wide range of viral pathogens. Structural studies of viruses by means of cryo-electron microscopy and three-dimensional image reconstruction methods have grown explosively in the last decade. Here we review the use of cryo-electron microscopy for the determination of the structures of a number of icosahedral viruses. These studies span more than 20 virus families. Representative examples illustrate the use of moderate- to low-resolution (7- to 35-A) structural analyses to illuminate functional aspects of viral life cycles including host recognition, viral attachment, entry, genome release, viral transcription, translation, proassembly, maturation, release, and transmission, as well as mechanisms of host defense. The success of cryo-electron microscopy in combination with three-dimensional image reconstruction for icosahedral viruses provides a firm foundation for future explorations of more-complex viral pathogens, including the vast number that are nonspherical or nonsymmetrical.

Adding the third dimension to virus life cycles: three-dimensional reconstruction of icosahedral viruses from cryo-electron micrographs.

Viruses are cellular parasites. The linkage between viral and host functions makes the study of a viral life cycle an important key to cellular functions. A deeper understanding of many aspects of viral life cycles has emerged from coordinated molecular and structural studies carried out with a wide range of viral pathogens. Structural studies of viruses by means of cryo-electron microscopy and three-dimensional image reconstruction methods have grown explosively in the last decade. Here we review the use of cryo-electron microscopy for the determination of the structures of a number of icosahedral viruses. These studies span more than 20 virus families. Representative examples illustrate the use of moderate- to low-resolution (7- to 35-A) structural analyses to illuminate functional aspects of viral life cycles including host recognition, viral attachment, entry, genome release, viral transcription, translation, proassembly, maturation, release, and transmission, as well as mechanisms of host defense. The success of cryo-electron microscopy in combination with three-dimensional image reconstruction for icosahedral viruses provides a firm foundation for future explorations of more-complex viral pathogens, including the vast number that are nonspherical or nonsymmetrical.

Immunoassays for the diagnosis of viral enteric pathogens

The accurate diagnosis of infectious diseases is important for the optimal management of infected patients as well as for the prevention of disease transmission to susceptible individuals. Because viral gastroenteritis constitutes an important cause of morbidity in children living in developed countries and of mortality in children living in developing countries, there has been a great deal of interest in the development of effective methods for the diagnosis and study of this disease. While there are a number of assay systems that are capable of accurate detection of the agents of viral gastroenteritis in the intestinal contents of infected individuals, solid phase enzyme immunoassays have been used widely for this purpose. The widespread utilization of enzyme immunoassays is based on the advantages inherent in the use of enzymatic markers. These advantages include the stability of enzyme-immunoglobulin conjugates, the high degree of sensitivity inherent in the magnifying nature of enzyme-substrate interactions, and the low cost of assays performed in simple reaction formats. Enzyme immunoassays have thus been developed and widely used for the detection and epidemiologic study of rotaviruses, adenoviruses, coxsackie viruses, hepatitis A virus, and other agents that replicate in the human gastrointestinal tract. In addition, latex agglutination assays and nucleic acid hybridization techniques have been applied to the rapid detection of enteric viruses. It is likely that the application of a number of assay systems will promote accurate identification of a wide range of viral pathogens under different clinical, epidemiologic, and laboratory situations.