Virology:
The study of the structure, growth, function, genetics, and reproduction of viruses, and Virus diseases.
JoVE Immunology and Infection
Plaque Assay for Murine Norovirus
Department of Microbiology and Immunology, University of Michigan, Ann Arbor
Here we describe a method to quantify infectious particles of murine norovirus (MNV), which is the only norovirus that efficiently replicates in cell culture. The plaque assay takes advantage of MNV’s tropism for murine macrophages and can be adapted for use with biological or environmental samples containing MNV.
JoVE Bioengineering
Microfluidic Chip Fabrication and Method to Detect Influenza
1Department of Mechanical Engineering, Boston University, 2Department of Biomedical Engineering, Boston University
An integrated microfluidic thermoplastic chip has been developed for use as a molecular diagnostic. The chip performs nucleic acid extraction, reverse transcriptase, and PCR. Methods for fabricating and running the chip are described.
JoVE Immunology and Infection
Simple and Robust in vivo and in vitro Approach for Studying Virus Assembly
1Department of Plant Pathology and Microbiology, University of California, Riverside, 2Department of Bioengineering, University of California, Riverside
A simple, efficient and robust way to synchronize the delivery of multiple viral components to plant cells via Agrobacterium-mediated transient expression is described. This approach is amenable for studying replication, encapsidation followed by in vitro reassembly of non-viral components into genome depleted optical viral ghosts suitable for biomedical applications.
JoVE Immunology and Infection
Generation of Recombinant Influenza Virus from Plasmid DNA
1Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, 2Departments of Microbiology and Medicine, and Global Health and Emerging Pathogens Institute, Mount Sinai School of Medicine
Rescue of influenza A viruses from plasmid DNA is a basic and essential experimental technique that allows influenza researchers to generate recombinant viruses to study multiple aspects in the biology of influenza virus, and to be used as potential vectors or vaccines.
JoVE Immunology and Infection
Protein Misfolding Cyclic Amplification of Prions
1Department of Civil Engineering, University of Nebraska at Lincoln, 2Department of Medical Microbiology and Immunology, Creighton University
Protein misfolding cyclic amplification (PMCA) is an in vitro assay for the study of prion conversion and strain and species barriers. It can also be used as a prion detection assay.
JoVE Immunology and Infection
In vitro Uncoating of HIV-1 Cores
Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine
Uncoating is an essential step in the early phase of the HIV-1 life cycle and is defined as the disassembly of the capsid shell and the release of the viral ribonucleoprotein complex (vRNP). Here, we demonstrate techniques for isolating intact cores from HIV-1 virions and for quantifying their uncoating in vitro.
JoVE General
Interview: HIV-1 Proviral DNA Excision Using an Evolved Recombinase
Current HIV-1 strategies act to suppress the viral life cycle but do not effectively eradicate infection. Here, we demonstrate that an engineered recombinase can efficiently excise integrated HIV-1 proviral DNA from the genome of infected cells.
JoVE Immunology and Infection
Propagating and Detecting an Infectious Molecular Clone of Maedi-visna Virus that Expresses Green Fluorescent Protein
Institute for Experimental Pathology, University of Iceland
We describe a molecular clone of maedi-visna virus that expresses GFP and is fully infectious. Replication of this virus can be detected by using fluorescence microscopy and flow cytometry.
JoVE Immunology and Infection
Preparation of Viral DNA from Nucleocapsids
Department of Molecular Biology, Princeton University
We describe the process of isolating high purity herpesvirus nucleocapsid DNA from infected cells. The final DNA captured from solution is of high concentration and purity, making it ideally suited for high-throughput sequencing, high fidelity PCR reactions, and transfections to produce new viral recombinants.
JoVE General
Heterokaryon Technique for Analysis of Cell Type-specific Localization
Department of Chemistry and Biochemistry, Worcester Polytechnic Institute- WPI
A flexible and efficient method for the characterization of cell type-specific protein localization and nucleocytoplasmic shuttling is described. This heterokaryon approach uses fluorescently-labeled fusion proteins to image protein localizations after cell fusion. The protocol is amenable to steady-state localizations or more dynamic determinations based on live cell imaging.
JoVE Immunology and Infection
In Vivo Imaging Systems (IVIS) Detection of a Neuro-Invasive Encephalitic Virus
Experimental Pathology, University of Texas Medical Branch
Utilizing luciferase and in vivo imaging systems (IVIS) as a novel means to identify disease endpoints before clinical developments occur. IVIS has allowed us to visualize in real time the invasion of encephalitic viruses over multiple days, providing a more accurate disease model for future study. It has also allowed us to identify the potential protective features of antivirals and vaccines faster than currently utilized animal models. The capability to utilize individual animals over multiple time points ensures reduced animal requirements, costs, and overall morbidity to the animals utilized ensuring a more humane and more scientific means of disease study.
JoVE General
Purification and Visualization of Influenza A Viral Ribonucleoprotein Complexes
Department of Zoology, University of British Columbia - UBC
The genome of the influenza A virus consists of eight separate complexes of RNA and proteins, termed viral ribonucleoprotein complexes (vRNPs). This paper describes the glycerol gradient purification and transmission electron microscopy visualization of influenza A vRNPs.
JoVE Immunology and Infection
Alphavirus Transducing System: Tools for Visualizing Infection in Mosquito Vectors
Microbiology, Immunology, and Pathology, Colorado State University
Methods for using alphavirus transducing systems to express fluorescent reporters in vitro and in adult mosquitoes are described. This technique may be adapted to express any protein of interest in lieu of or in addition to a reporter.
JoVE General
Aseptic Laboratory Techniques: Plating Methods
Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles
When working with media and reagents used to culture microorganisms, aseptic technique must be practiced to ensure contamination is minimized. A variety of plating methods are routinely used to isolate, propagate, or enumerate bacteria and phage, all of which incorporate procedures that maintain the sterility of experimental materials.
JoVE Immunology and Infection
Establishing a Liquid-covered Culture of Polarized Human Airway Epithelial Calu-3 Cells to Study Host Cell Response to Respiratory Pathogens In vitro
The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.
JoVE Immunology and Infection
Using Reverse Genetics to Manipulate the NSs Gene of the Rift Valley Fever Virus MP-12 Strain to Improve Vaccine Safety and Efficacy
Department of Pathology, University of Texas Medical Branch
The reverse genetics system for the Rift Valley fever virus MP-12 vaccine strain is a useful tool for creating additional MP-12 mutants with increased attenuation and immunogenicity. We describe the protocol to generate and characterize NSs mutant strains.
JoVE Immunology and Infection
Microwave Assisted Rapid Diagnosis of Plant Virus Diseases by Transmission Electron Microscopy
1Institute of Plant Sciences, University of Graz, 2Institute for Electron Microscopy and Fine Structure Research, Graz University of Technology
This study describes a method that allows the rapid and clear diagnosis of plant virus diseases in about half a day by using a combination of microwave assisted plant sample preparation for transmission electron microscopy and negative staining methods.
JoVE Immunology and Infection
Production and Titering of Recombinant Adeno-associated Viral Vectors
1School of Medical Sciences, College of Life Sciences and Medicine, University of Aberdeen, 2Translational Neuroscience Facility and Department of Physiology, School of Medical Sciences, University of New South Wales, 3Department of Biochemistry and Molecular Biophysics, Columbia University
Recombinant adeno-associated virus (rAAVs) vectors are becoming increasingly valuable for in vivo studies in animals. We describe how rAAVs can be produced in the laboratory and how these vectors can be titered to give an accurate reading of the number of infectious particles produced.
JoVE Immunology and Infection
piggyBac Transposon System Modification of Primary Human T Cells
1Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, 2Department of Medicine, Division of Nephrology, Baylor College of Medicine, 3Department of Immunology and Pathology, Shinshu University School of Medicine, 4Center for Cell and Gene Therapy, Baylor College of Medicine, 5Department of Pediatrics, Baylor College of Medicine, 6Program in Cell and Molecular Biology, Baylor College of Medicine, 7Department of Molecular Virology and Microbiology, Baylor College of Medicine, 8Michael E. DeBakey VA Medical Center
We describe a method to genetically modify primary human T cells with a transgene using the non-viral piggyBac transposon system. T cells modified to using the piggyBac transposon system exhibit stable transgene expression.
JoVE General
Identification of Protein Interacting Partners Using Tandem Affinity Purification
Section of Virology, Department of Medicine, Imperial College London
Tandem affinity purification is a robust approach for the identification of protein binding partners. As proof of concept, this methodology was applied to the well-characterized translation initiation factor eIF4E to co-precipitate the host cell factors involved in translation initiation. This method is easily adapted to any cellular or viral protein.
JoVE Clinical and Translational Medicine
Detection and Genogrouping of Noroviruses from Children's Stools By Taqman One-step RT-PCR
1Laboratorio de Investigación y Desarrollo (LID), Universidad Peruana Cayetano Heredia, 2Bloomberg School of Public Health, Johns Hopkins University, 3Laboratorio de Diagnostico Molecular, Facultad de Medicina, University of Concepcion,Chile, 4University of California San Diego School of Medicine
A One-Step RT-PCR assay for detection and genogroup identification of Norovirus isolates from children’s stools, that utilizes primers and TaqMan probes specific to the open reading frame 1 (ORF1)-ORF2 junction region, the most conserved region of the Norovirus genome is described. A non-commercial, cost-effective RNA extraction method is detailed.
JoVE Immunology and Infection
Induction of Experimental Autoimmune Hypophysitis in SJL Mice
Department of Pathology, The Johns Hopkins University
This video shows how to induce autoimmune hypophysitis in SJL mice and how to assess its severity by histopathology.
JoVE Immunology and Infection
RNAi Screening for Host Factors Involved in Vaccinia Virus Infection using Drosophila Cells
Department of Microbiology, Penn Genome Frontiers Institute, University of Pennsylvania
Novel host factors involved in viral infection can be identified through cell-based genome-wide loss of function RNAi screening. A Drosophila cell culture model is particularly amenable to this approach due to the ease and efficiency of RNAi. Here we demonstrate this technique using vaccinia virus as an example.
JoVE Immunology and Infection
ampliPHOX Colorimetric Detection on a DNA Microarray for Influenza
InDevR, Inc.
ampliPHOX colorimetric detection technology is presented as an inexpensive alternative to fluorescence detection for microarrays. Based on photopolymerization, ampliPHOX produces solid polymer spots visible to the naked eye in just a few minutes. Results are then imaged and automatically interpreted with a simple yet powerful software package.
JoVE Bioengineering
Methods Development for Blood Borne Macrophage Carriage of Nanoformulated Antiretroviral Drugs
Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center
Nanoparticles of indinavir, ritonavir, efavirenz and atazanavir were manufactured using wet milling, homogenization and ultrasonication. These nanoformulations, collectively termed nanoformulated antiretroviral therapy (nanoART), assessed macrophage-based drug delivery. Monocyte-derived macrophage nanoART uptake, retention and sustained release were determined. These preliminary studies suggest the potential of nanoART for clinical use.
JoVE Immunology and Infection
Protocol for Recombinant RBD-based SARS Vaccines: Protein Preparation, Animal Vaccination and Neutralization Detection
Lindsley F. Kimball Research Institute, New York Blood Center
This protocol describes a general procedure for studying recombinant receptor-binding domain (RBD)-based subunit vaccines against SARS. It includes methods for transfection and expression of RBD protein in 293T cells, immunization of mice with RBD and detection of neutralization activity of mouse sera using an established SARS pseudovirus neutralization assay.
JoVE Immunology and Infection
Affinity Purification of Influenza Virus Ribonucleoprotein Complexes from the Chromatin of Infected Cells
Department of Virology, Universitätsklinikum Freiburg
Influenza viruses replicate their RNA genome in association with host-cell chromatin. Here, we present a method to purify intact viral ribonucleoprotein complexes from the chromatin of infected cells. Purified viral complexes can be analyzed by both Western blot and primer extension of protein and RNA content, respectively.
JoVE General
A Cell-to-cell Macromolecular Transport Assay in Planta Utilizing Biolistic Bombardment
1Department of Biochemistry and Cell Biology, State University of New York at Stony Brook, 2Bio-Medical Engineering Department, NED University of Engineering and Technology
Macromolecular trafficking between plant cells can be assessed by transiently expressing a fluorescently-tagged protein of interest and analyzing its intra- and intercellular distribution by confocal microscopy.
JoVE Immunology and Infection
Development of Cell-type specific anti-HIV gp120 aptamers for siRNA delivery
1Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, 2Graduate School of Biological Sciences, Beckman Research Institute of City of Hope, 3Shared Resource-DNA/RNA Peptide, Beckman Research Institute of City of Hope
Several 2’-Fluoro RNA aptamers against HIV-1Ba-L gp120 with nanomole affinity are isolated from a RNA library by in vitro SELEX procedure. A new dual inhibitory function anti-gp120 aptamer-siRNA chimera is created and shows considerable promise for systemic anti-HIV therapy.
JoVE Immunology and Infection
Identifying Dysregulated Genes Induced by Kaposi's Sarcoma-associated Herpesvirus (KSHV)
Host cell factors play a critical role in the establishment and maintenance of Kaposi's sarcoma (KS). We outline methods to identify host cell factors altered in KSHV-infected DMVEC cells, and in KS tumor tissue. Cellular genes altered by virus will serve as potential target(s) for novel therapeutics.
JoVE Immunology and Infection
Particle Agglutination Method for Poliovirus Identification
1Department of Virology II, National Institute of Infectious Diseases, 2New Product Design Department, Fujirebio Inc.
A recently developed novel particle agglutination (PA) assay utilizing virus receptor molecule allowed a rapid and easy identification of poliovirus (PV). In this article, we will show the procedure for the PA assay for PV identification.
JoVE Bioengineering
High-throughput Protein Expression Generator Using a Microfluidic Platform
We present a microfluidic approach for the expression of protein arrays. The device consists of thousands of reaction chambers controlled by micro-mechanical valves. The microfluidic device is mated to a microarray-printed gene library. These genes are then transcribed and translated on-chip, resulting in a protein array ready for experimental use.
JoVE Immunology and Infection
Isolation of Lymphocytes from Mouse Genital Tract Mucosa
1Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, 2California NanoSystems
An efficient way to isolate lymphocytes from mouse genital tract is described. This method takes advantage of enzyme digestion and Percoll gradient separation to allow efficient isolation. This technique is also adaptable to for use in other species
JoVE General
Preparation of Cell-lines for Conditional Knockdown of Gene Expression and Measurement of the Knockdown Effects on E4orf4-Induced Cell Death
Department of Molecular Microbiology, Faculty of Medicine, Technion - Israel Institute of Technology
Contribution of the ACF chromatin remodeling factor to E4orf4-induced cell death was measured. The protocol includes selection of cell clones in which doxycycline treatment induces conditional knockdown of the ACF subunits Acf1 and SNF2h, and use of the DAPI assay to measure E4orf4-induced cell death in the inducible cell lines.
JoVE Immunology and Infection
Reverse Genetics Mediated Recovery of Infectious Murine Norovirus
Section of Virology, Imperial College London
Noroviruses are a major cause of gastroenteritis yet molecular techniques for their characterisation are still relatively new. Here we report two different reverse genetics approaches for the efficient recovery of murine norovirus (MNV), the only member of this genus which can be propagated in cell culture.
JoVE Immunology and Infection
Efficient Recombinant Parvovirus Production with the Help of Adenovirus-derived Systems
1Tumour Virology Division F010, German Cancer Research Center (DKFZ), 2Inserm Unit 701, German Cancer Research Center (DKFZ)
Here we describe a protocol based only on cell infection, which improves the efficiency of recombinant parvovirus production by more than 100 fold in comparison to other protocols in use. This protocol relies on the use of a novel adenovirus 5-based helper containing the parvovirus VP transcription unit (Ad-VP).
JoVE Immunology and Infection
Two Methods of Heterokaryon Formation to Discover HCV Restriction Factors
1Division of Experimental Virology, Twincore, Centre for Experimental and Clinical Infection Research, 2Aaron Diamond AIDS Research Center, Laboratory of Retrovirology, The Rockefeller University, NY
We describe two methods for conditional trans-complementation of hepatitis C virus (HCV) assembly and the completion of the full viral life cycle, which rely on heterokaryon formation. These techniques are suitable to screen for cell lines that express dominant restriction factors, which preclude production of infectious HCV progeny.
JoVE Immunology and Infection
A Primary Neuron Culture System for the Study of Herpes Simplex Virus Latency and Reactivation
1Department of Microbiology, New York University School of Medicine, 2Molecular Neurobiology Program, Skirball Institute for Biomolecular Medicine, New York University School of Medicine, 3Department of Otolaryngology, New York University School of Medicine, 4Department of Cell Biology, New York University School of Medicine, 5Department of Physiology and Neuroscience, New York University School of Medicine, 6Department of Psychiatry, New York University School of Medicine, 7Center for Neural Science, New York University School of Medicine
The protocol describes an efficient and reproducible model system to study herpes simplex virus type 1 (HSV-1) latency and reactivation. The assay employs homogenous sympathetic neuron cultures and allows for the molecular dissection of virus-neuron interactions using a variety of tools including RNA interference and expression of recombinant proteins.
JoVE General
Transduction of Human Cells with Polymer-complexed Ecotropic Lentivirus for Enhanced Biosafety
Department of Cell Biology and Human Anatomy, School of Medicine, University of California, Davis
Lentiviruses are a valuable research tool for exploring gene function; however, researchers may wish to avoid production of pantropic lentivirus encoding known or suspected oncogenes. As an alternative, we present a safer protocol for use of ecotropic lentivirus on human cells modified to express the ecotropic receptor mSlc7a1.
JoVE Immunology and Infection
Quantitative Analyses of all Influenza Type A Viral Hemagglutinins and Neuraminidases using Universal Antibodies in Simple Slot Blot Assays
1Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health canada, 2National Institute for the Control of Pharmaceutical and Biological Products, The State Food and Drug Administration, Beijing, 3Department of Biochemistry, Microbiology and Immunology, University of Ottawa, 4Microbiology Department, Faculty of Medicine, King Abdulaziz University, 5National Microbiology Laboratory, Public Health Agency of Canada
A simple slot blot method was developed for the quantification of influenza viral hemagglutinin and neuraminidase using universal antibodies targeting their most conserved sequences identified through bioinformatics analyses. This innovative approach may provide a useful alternative to quantitative determination of all viral hemagglutinin and neuraminidase.
JoVE Neuroscience
Viral Tracing of Genetically Defined Neural Circuitry
1Department of Genetics, Harvard Medical School, 2Howard Hughes Medical Institute, Harvard Medical School
A method of tracing synaptically connected neurons is described. We use TVA specificity of an upstream cell to probe whether a cell population of interest receives synaptic input from genetically defined cell types.
JoVE Immunology and Infection
Dissecting Host-virus Interaction in Lytic Replication of a Model Herpesvirus
1Center for Autophagy Research, Department of Internal Medicine, UT Southwestern Medical Center, 2Department of Microbiology, UT Southwestern Medical Center
We describe a protocol to identify key roles of host signaling molecules in lytic replication of a model herpesvirus, gamma herpesvirus 68 (γHV68). Utilizing genetically modified mouse strains and embryonic fibroblasts for γHV68 lytic replication, the protocol permits both phenotypic characterization and molecular interrogation of virus-host interactions in viral lytic replication.
JoVE Immunology and Infection
Engineering and Evolution of Synthetic Adeno-Associated Virus (AAV) Gene Therapy Vectors via DNA Family Shuffling
1Cluster of Excellence CellNetworks, Department of Infectious Diseases, Virology, Heidelberg University, 2Department of Infectious Diseases, Virology, Heidelberg University
We demonstrate the basic technique to molecularly engineer and evolve synthetic Adeno-associated viral (AAV) gene therapy vectors via DNA family shuffling. Moreover, we provide general guidelines and representative examples for selection and analysis of individual chimeric capsids with enhanced properties on target cells in culture or in mice.
JoVE Immunology and Infection
Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Viral Populations and Pathogenesis lab and CNRS 3015, Institut Pasteur
The present article describes the steps required to isolate and characterize RNA polymerase fidelity variants of RNA viruses and how to use mutation frequency data to confirm fidelity changes in tissue culture.
JoVE Immunology and Infection
Rapid Diagnosis of Avian Influenza Virus in Wild Birds: Use of a Portable rRT-PCR and Freeze-dried Reagents in the Field
1USGS Western Ecological Research Center, 2Wildlife Health Center, University of California, Davis, 3Department of Population Health and Reproduction, University of California, Davis, 4Department of Veterinary and Biomedical Sciences, University of Minnesota, 5Science Applications International Corporation
This study describes diagnosis of avian influenza in wild birds using a portable rRT-PCR system. The method takes advantage of freeze-dried reagents to screen wild birds in a non-laboratory setting, typical of an outbreak scenario. Use of molecular tools provides accurate and sensitive alternatives for rapid diagnosis.
JoVE General
Protein Membrane Overlay Assay: A Protocol to Test Interaction Between Soluble and Insoluble Proteins in vitro
Department of Biochemistry and Cell Biology, State University of New York
Testing protein-protein interaction is indispensable for dissection of protein functionality. Here, we introduce an in vitro protein-protein binding assay to probe a membrane-immobilized protein with a soluble protein. This assay provides a reliable method to test interaction between an insoluble protein and a protein in solution.
JoVE Immunology and Infection
Establishment of Epstein-Barr Virus Growth-transformed Lymphoblastoid Cell Lines
1Stony Brook Children's Hospital, State University of New York at Stony Brook, 2Department of Pediatrics, State University of New York at Stony Brook, 3Department of Molecular Genetics, State University of New York at Stony Brook, 4Department of Microbiology, State University of New York at Stony Brook
We describe a method for generating transformed B cell lines using Epstein-Barr virus. We also illustrate a novel assay that can identify B cells destined to undergo transformation as early as three days after infection.
JoVE Immunology and Infection
An In vitro Co-infection Model to Study Plasmodium falciparum-HIV-1 Interactions in Human Primary Monocyte-derived Immune Cells
Infectious Disease Research Center, CHUL (CHUQ), Quebec City, Quebec, Canada
We have developed an in vitro malaria-HIV-1 co-infection model to study the impact of Plasmodium falciparum on the HIV-1 replicative cycle in human primary monocyte-derived macrophages. This versatile system can easily be adapted to other primary cell types susceptible to HIV-1 infection.
JoVE Immunology and Infection
Recurrent Herpetic Stromal Keratitis in Mice, a Model for Studying Human HSK
Department of Ophthalmology, Saint Louis University
Most studies of herpetic corneal disease use a primary infection model. However, primary infection with HSV-1 does not typically lead to human disease. Here we describe a recurrent model of herpetic corneal disease, which more closely mimics human disease.
JoVE General
Monitoring Plasmid Replication in Live Mammalian Cells over Multiple Generations by Fluorescence Microscopy
Department of Oncology, University of Wisconsin - Madison
A method of observing individual DNA molecules in live cells is described. The technique is based on the binding of a fluorescently tagged lac repressor protein to binding sites engineered into the DNA of interest. This method can be adapted to follow many recombinant DNAs in live cells over time.
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