scholarly journals A Model for the Production of Regulatory Grade Viral Hemorrhagic Fever Exposure Stocks: From Field Surveillance to Advanced Characterization of SFTSV

Viruses ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 958
Author(s):  
Unai Perez-Sautu ◽  
Se Hun Gu ◽  
Katie Caviness ◽  
Dong Hyun Song ◽  
Yu-Jin Kim ◽  
...  
Keyword(s):  
High Titer ◽  
Case Fatality ◽  
Hemorrhagic Fever ◽  
Advanced Characterization ◽  
Human Case ◽  
Viral Agent ◽  
Functional Studies ◽  
Viral Stock

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging human pathogen, endemic in areas of China, Japan, and the Korea (KOR). It is primarily transmitted through infected ticks and can cause a severe hemorrhagic fever disease with case fatality rates as high as 30%. Despite its high virulence and increasing prevalence, molecular and functional studies in situ are scarce due to the limited availability of high-titer SFTSV exposure stocks. During the course of field virologic surveillance in 2017, we detected SFTSV in ticks and in a symptomatic soldier in a KOR Army training area. SFTSV was isolated from the ticks producing a high-titer viral exposure stock. Through the use of advanced genomic tools, we present here a complete, in-depth characterization of this viral stock, including a comparison with both the virus in its arthropod source and in the human case, and an in vivo study of its pathogenicity. Thanks to this detailed characterization, this SFTSV viral exposure stock constitutes a quality biological tool for the study of this viral agent and for the development of medical countermeasures, fulfilling the requirements of the main regulatory agencies.

scholarly journals Advanced characterizations of nanoparticles for drug delivery: investigating their properties through the techniques used in their evaluations

2017 ◽  
Vol 6 (4) ◽  
pp. 355-372 ◽  
Author(s):  
Syed Mahmood ◽  
Uttam Kumar Mandal ◽  
Bappaditya Chatterjee ◽  
Muhammad Taher
Keyword(s):  
Drug Delivery ◽  
Advanced Characterization ◽  
Data Interpretation ◽  
Review Article ◽  
The Body ◽  
Drug Molecule ◽  
Drug Molecules ◽  
Preparation Techniques

AbstractNanomedicine has achieved a huge success in delivering a wide variety of drug molecules into the target site of the body. In this respect, the characterization of nanoformulation is very important to investigate the drug molecule together with its carrier as a nanoform during formulation, storage, and in vivo transport through the body. This review article summarizes important advanced characterization techniques of nanoformulation with respect to their theories, use of required instrumental parameters, sample preparation techniques, data interpretation, etc., to exploit them for the best possible results. This review article also sheds a glimpse to the shortcomings of these techniques together with further advancements required in future.

scholarly journals Identification and characterization of T reg–like cells in zebrafish

2017 ◽  
Vol 214 (12) ◽  
pp. 3519-3530 ◽  
Author(s):  
Melissa Kasheta ◽  
Corrie A. Painter ◽  
Finola E. Moore ◽  
Riadh Lobbardi ◽  
Alysia Bryll ◽  
...  
Keyword(s):  
T Lymphocytes ◽  
Live Cell Imaging ◽  
Genetic Ablation ◽  
Functional Studies ◽  
Normal Functions ◽  
Inflammatory Phenotype ◽  
Identification And Characterization

Regulatory T (T reg) cells are a specialized sublineage of T lymphocytes that suppress autoreactive T cells. Functional studies of T reg cells in vitro have defined multiple suppression mechanisms, and studies of T reg–deficient humans and mice have made clear the important role that these cells play in preventing autoimmunity. However, many questions remain about how T reg cells act in vivo. Specifically, it is not clear which suppression mechanisms are most important, where T reg cells act, and how they get there. To begin to address these issues, we sought to identify T reg cells in zebrafish, a model system that provides unparalleled advantages in live-cell imaging and high-throughput genetic analyses. Using a FOXP3 orthologue as a marker, we identified CD4-enriched, mature T lymphocytes with properties of T reg cells. Zebrafish mutant for foxp3a displayed excess T lymphocytes, splenomegaly, and a profound inflammatory phenotype that was suppressed by genetic ablation of lymphocytes. This study identifies T reg–like cells in zebrafish, providing both a model to study the normal functions of these cells in vivo and mutants to explore the consequences of their loss.

scholarly journals Glycoprotein N-linked glycans play a critical role in arenavirus pathogenicity

2021 ◽  
Vol 17 (3) ◽  
pp. e1009356
Author(s):  
Takaaki Koma ◽  
Cheng Huang ◽  
Adrian Coscia ◽  
Steven Hallam ◽  
John T. Manning ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Rational Design ◽  
Critical Role ◽  
Case Fatality ◽  
Hemorrhagic Fever ◽  
Wild Type ◽  
Virus Growth ◽  
Glycosylation Sites

Several arenaviruses cause hemorrhagic fevers in humans with high case fatality rates. A vaccine named Candid#1 is available only against Junin virus (JUNV) in Argentina. Specific N-linked glycans on the arenavirus surface glycoprotein (GP) mask important epitopes and help the virus evade antibody responses. However the role of GPC glycans in arenavirus pathogenicity is largely unclear. In a lethal animal model of hemorrhagic fever-causing Machupo virus (MACV) infection, we found that a chimeric MACV with the ectodomain of GPC from Candid#1 vaccine was partially attenuated. Interestingly, mutations resulting in acquisition of N-linked glycans at GPC N83 and N166 frequently occurred in late stages of the infection. These glycosylation sites are conserved in the GPC of wild-type MACV, indicating that this is a phenotypic reversion for the chimeric MACV to gain those glycans crucial for infection in vivo. Further studies indicated that the GPC mutant viruses with additional glycans became more resistant to neutralizing antibodies and more virulent in animals. On the other hand, disruption of these glycosylation sites on wild-type MACV GPC rendered the virus substantially attenuated in vivo and also more susceptible to antibody neutralization, while loss of these glycans did not affect virus growth in cultured cells. We also found that MACV lacking specific GPC glycans elicited higher levels of neutralizing antibodies against wild-type MACV. Our findings revealed the critical role of specific glycans on GPC in arenavirus pathogenicity and have important implications for rational design of vaccines against this group of hemorrhagic fever-causing viruses.

scholarly journals Construction and Nonclinical Testing of a Puumala Virus Synthetic M Gene-Based DNA Vaccine

2012 ◽  
Vol 20 (2) ◽  
pp. 218-226 ◽  
Author(s):  
R. L. Brocato ◽  
M. J. Josleyn ◽  
V. Wahl-Jensen ◽  
C. S. Schmaljohn ◽  
J. W. Hooper
Keyword(s):  
Dna Vaccine ◽  
Neutralizing Antibodies ◽  
High Titer ◽  
Disease Model ◽  
Case Fatality ◽  
Hemorrhagic Fever ◽  
Puumala Virus ◽  
M Gene ◽  
Reading Frame ◽  
Andes Virus

ABSTRACTPuumala virus (PUUV) is a causative agent of hemorrhagic fever with renal syndrome (HFRS). Although PUUV-associated HFRS does not result in high case-fatality rates, the social and economic impact is considerable. There is no licensed vaccine or specific therapeutic to prevent or treat HFRS. Here we report the synthesis of a codon-optimized, full-length M segment open reading frame and its cloning into a DNA vaccine vector to produce the plasmid pWRG/PUU-M(s2). pWRG/PUU-M(s2) delivered by gene gun produced high-titer neutralizing antibodies in hamsters and nonhuman primates. Vaccination with pWRG/PUU-M(s2) protected hamsters against infection with PUUV but not against infection by related HFRS-associated hantaviruses. Unexpectedly, vaccination protected hamsters in a lethal disease model of Andes virus (ANDV) in the absence of ANDV cross-neutralizing antibodies. This is the first evidence that an experimental DNA vaccine for HFRS can provide protection in a hantavirus lethal disease model.

scholarly journals Genomic characterization of serial-passaged Ebola virus in a boa constrictor cell line

2016 ◽  
Author(s):  
Greg Fedewa ◽  
Sheli R. Radoshitzky ◽  
Xiǎolì Chī ◽  
Lián Dǒngb ◽  
Melissa Spear ◽  
...  
Keyword(s):  
Cell Line ◽  
Ebola Virus ◽  
Cytopathic Effect ◽  
Case Fatality ◽  
Hemorrhagic Fever ◽  
Marburg Virus ◽  
Boa Constrictor ◽  
Genomic Adaptation ◽  
Genomic Characterization

ABSTRACTEbola virus disease (EVD) is a viral hemorrhagic fever with a high case-fatality rate in humans. EVD is caused by four members of the filoviral genusEbolavirus, with Ebola virus (EBOV) being the most notorious one. Although bats are discussed as potential ebolavirus reservoirs, limited data actually support this hypothesis. Glycoprotein 2 (GP2) of reptarenaviruses, known to infect only boa constrictors and pythons, are similar in sequence and structure to ebolaviral glycoprotein 2 (GP2), suggesting that EBOV may be able to infect snake cells. We therefore serially passaged EBOV and a distantly related filovirus, Marburg virus (MARV), in the boa constrictor kidney cell line, JK, and characterized viral growth and mutational frequency by sequencing. We observed that EBOV efficiently infected and replicated in JK cells, but MARV did not. In contrast to most cell lines, EBOV infected JK cells did not result in obvious cytopathic effect (CPE). Genomic characterization of serial-passaged EBOV in JK cells revealed that genomic adaptation was not required for infection. Deep sequencing coverage (>10,000x) demonstrated the existence of only a single non-synonymous variant (EBOV glycoprotein precursor preGP T544I) of unknown significance within the viral population that exhibited a shift in frequency of at least 10% over six passages. Our data suggest that boid snake derived cells are competent for filovirus infection without appreciable genomic adaptation; that cellular filovirus infection without CPE may be more common than currently appreciated; and that there may be significant differences between the natural host spectra of ebolaviruses and marburgviruses.IMPORTANCEEbola virus (EBOV) causes a high case-fatality form of viral hemorrhagic fever. The natural reservoir of EBOV remains unknown. EBOV is distantly related to Marburg virus (MARV), which has been found in bats in the wild. The glycoprotein of a reptarenavirus known to infect boid snakes (pythons and boas) shows similarity in sequence and structure to these viruses, suggesting that EBOV and MARV may be able to infect and replicate in snake cells. We demonstrate that JK, a boa constrictor cell line, does not support MARV infection, but does support EBOV infection without causing overt cytopathic effect or the need for appreciable adaptation. These findings suggest different filoviruses may have a more diverse natural host spectra than previously thought.

scholarly journals IgY antibodies against Ebola virus possess post-exposure protection in a murine pseudovirus challenge model and excellent thermostability

2021 ◽  
Vol 15 (3) ◽  
pp. e0008403
Author(s):  
Yuan Zhang ◽  
Yanqiu Wei ◽  
Yunlong Li ◽  
Xuan Wang ◽  
Yang Liu ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Ebola Virus ◽  
Protective Efficacy ◽  
High Titer ◽  
Lethal Dose ◽  
Hemorrhagic Fever ◽  
High Dose ◽  
Excellent Thermal Stability ◽  
Post Exposure

Ebola virus (EBOV) is one of the most virulent pathogens that causes hemorrhagic fever and displays high mortality rates and low prognosis rates in both humans and nonhuman primates. The post-exposure antibody therapies to prevent EBOV infection are considered effective as of yet. However, owing to the poor thermal stability of mammalian antibodies, their application in the tropics has remained limited. Therefore, a thermostable therapeutic antibody against EBOV was developed modelled on the poultry(chicken) immunoglobulin Y (IgY). The IgY antibodies retaining their neutralising activity at 25°C for one year, displayed excellent thermal stability, opposed to conventional polyclonal antibodies (pAbs) or monoclonal antibodies (mAbs). Laying hens were immunised with a variety of EBOV vaccine candidates and it was confirmed that VSVΔG/EBOVGP encoding the EBOV glycoprotein could induce high titer neutralising antibodies against EBOV. The therapeutic efficacy of immune IgY antibodies in vivo was evaluated in the newborn Balb/c mice who have been challenged with the VSVΔG/EBOVGP model. Mice that have been challenged with a lethal dose of the pseudovirus were treated 2 or 24 h post-infection with different doses of anti-EBOV IgY. The group receiving a high dose of 106 NAU/kg (neutralising antibody units/kilogram) showed complete protection with no symptoms of a disease, while the low-dose group was only partially protected. Conversely, all mice receiving naive IgY died within 10 days. In conclusion, the anti-EBOV IgY exhibits excellent thermostability and protective efficacy. Anti-EBOV IgY shows a lot of promise in entering the realm of efficient Ebola virus treatment regimens.

scholarly journals Molecular and Functional Characterization of Circulating Tumor Cells: From Discovery to Clinical Application

2019 ◽  
Vol 66 (1) ◽  
pp. 97-104 ◽  
Author(s):  
Luis Enrique Cortés-Hernández ◽  
Zahra Eslami-S ◽  
Klaus Pantel ◽  
Catherine Alix-Panabières
Keyword(s):  
Tumor Cells ◽  
Circulating Tumor Cells ◽  
Liquid Biopsy ◽  
Functional Characterization ◽  
Clinical Information ◽  
In Vivo Models ◽  
Functional Studies

Abstract BACKGROUND One of the objectives for the liquid biopsy is to become a surrogate to tissue biopsies in diagnosis of cancer as a minimally invasive method, with clinical utility in real-time follow-ups of patients. To achieve this goal, it is still necessary to achieve a better understanding of the mechanisms of cancer and the biological principles that govern its behavior, particularly with regard to circulating tumor cells (CTCs). CONTENT The isolation, enumeration, detection, and characterization of CTCs have already proven to provide relevant clinical information about patient prognosis and treatment prediction. Moreover, CTCs can be analyzed at the genome, proteome, transcriptome, and secretome levels and can also be used for functional studies in in vitro and in vivo models. These features, taken together, have made CTCs a very valuable biosource. SUMMARY To further advance the field and discover new clinical applications for CTCs, several studies have been performed to learn more about these cells and better understand the biology of metastasis. In this review, we describe the recent literature on the topic of liquid biopsy with particular focus on the biology of CTCs.

scholarly journals Spatio-temporal expression and distribution of collagen VI during zebrafish development

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Valentina Tonelotto ◽  
Valeria Trapani ◽  
Sandrine Bretaud ◽  
Stefanie Elisabeth Heumüller ◽  
Raimund Wagener ◽  
...  
Keyword(s):  
Polyclonal Antibodies ◽  
Adult Life ◽  
Model Organism ◽  
Collagen Vi ◽  
Bioinformatics Analyses ◽  
Functional Studies ◽  
Gene And Protein Expression ◽  
Genes Encoding

AbstractCollagen VI (ColVI) is an extracellular matrix (ECM) protein involved in a range of physiological and pathological conditions. Zebrafish (Danio rerio) is a powerful model organism for studying vertebrate development and for in vivo analysis of tissue patterning. Here, we performed a thorough characterization of ColVI gene and protein expression in zebrafish during development and adult life. Bioinformatics analyses confirmed that zebrafish genome contains single genes encoding for α1(VI), α2(VI) and α3(VI) ColVI chains and duplicated genes encoding for α4(VI) chains. At 1 day post-fertilization (dpf) ColVI transcripts are expressed in myotomes, pectoral fin buds and developing epidermis, while from 2 dpf abundant transcript levels are present in myosepta, pectoral fins, axial vasculature, gut and craniofacial cartilage elements. Using newly generated polyclonal antibodies against zebrafish α1(VI) protein, we found that ColVI deposition in adult fish delineates distinct domains in the ECM of several organs, including cartilage, eye, skin, spleen and skeletal muscle. Altogether, these data provide the first detailed characterization of ColVI expression and ECM deposition in zebrafish, thus paving the way for further functional studies in this species.

scholarly journals Human diseases associated with defects in assembly of OXPHOS complexes

2018 ◽  
Vol 62 (3) ◽  
pp. 271-286 ◽  
Author(s):  
Daniele Ghezzi ◽  
Massimo Zeviani
Keyword(s):  
Mitochondrial Disorders ◽  
Molecular Structures ◽  
In Vivo Models ◽  
Functional Studies ◽  
Assembly Factors ◽  
Human Disorders ◽  
The Individual ◽  
Next Generation Sequencing Ngs

The structural biogenesis and functional proficiency of the multiheteromeric complexes forming the mitochondrial oxidative phosphorylation system (OXPHOS) require the concerted action of a number of chaperones and other assembly factors, most of which are specific for each complex. Mutations in a large number of these assembly factors are responsible for mitochondrial disorders, in most cases of infantile onset, typically characterized by biochemical defects of single specific complexes. In fact, pathogenic mutations in complex-specific assembly factors outnumber, in many cases, the repertoire of mutations found in structural subunits of specific complexes. The identification of patients with specific defects in assembly factors has provided an important contribution to the nosological characterization of mitochondrial disorders, and has also been a crucial means to identify a huge number of these proteins in humans, which play an essential role in mitochondrial bioenergetics. The wide use of next generation sequencing (NGS) has led to and will allow the identifcation of additional components of the assembly machinery of individual complexes, mutations of which are responsible for human disorders. The functional studies on patients’ specimens, together with the creation and characterization of in vivo models, are fundamental to better understand the mechanisms of each of them. A new chapter in this field will be, in the near future, the discovery of mechanisms and actions underlying the formation of supercomplexes, molecular structures formed by the physical, and possibly functional, interaction of some of the individual respiratory complexes, particularly complex I (CI), III (CIII), and IV (CIV).

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