A TIRF Microscopy Technique for Real-time, Simultaneous Imaging of the TCR and its Associated Signaling Proteins
The compartmentalization of proteins either within the plasma membrane or into intracellular locations is one regulatory mechanism that can greatly influence signaling outcomes; hence, to understand signaling it is important to study the spatial and temporal behavior of the proteins involved. We describe here a TIRF microscopy based system to study signal transduction in T cells, but is broadly applicable.
Supported planar bilayers are powerful tools that can be used to model the molecular interactions in an immunological synapse. Here, we show methods for anchoring cell adhesion proteins known to modulate synapse formation to the upper leaflet of the lipid bilyer and visualize synapse formation using TIRF microscopy.
1Department of Medicine, Division of Infectious Diseases, Massachusetts General Hospital, Harvard Medical School, 2Department of Mechanical and Aerospace Engineering, The Ohio State University, 3Center for Computational and Integrative Biology, Massachusetts General Hospital, Harvard Medical School, 4Dept. of Chemical and Biomolecular Engineering, Vanderbilt University
A method is described to individually select, manipulate, and image live pathogens using an optical trap coupled to a spinning disk microscope. The optical trap provides spatial and temporal control of organisms and places them adjacent to host cells. Fluorescence microscopy captures dynamic intercellular interactions with minimal perturbation to cells.
1Department of Pathology, New York University Langone School of Medicine, 2Program in Molecular Pathogenesis, Marty and Helen Kimmel Center for Biology and Medicine and Skirball Institute for Biomolecular Medicine, 3Laboratory of Molecular Immunogenetics, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, 4Veteran Affairs New York Harbor Healthcare System
This article describes a method to visualize formation of an HIV-1 envelope-induced virological synapse on glass supported planar bilayers by total internal reflection fluorescence (TIRF) microscopy. The method can also be combined with immunofluorescence staining to detect activation and redistribution of signaling molecules that occur during HIV-1 envelope-induced virological synapse formation.
Many infections elicit a strong CTL response, but occasionally, the quantity of responding cells does not correlate to control of the pathogen1. One measure of CTL quality is their ability to kill specifically2. CFSE labeling of target cells can be used to investigate this CTL response quality in vivo3,4.
Artificial Antigen Presenting Cell (aAPC) Mediated Activation and Expansion of Natural Killer T Cells
Here we describe a method for activating and expanding human NKT cells from bulk T cell populations using artificial antigen presenting cells (aAPC). The use of CD1d-based aAPC provides a standardized method for generating high numbers of functional NKT cells.
Analyzing Cellular Internalization of Nanoparticles and Bacteria by Multi-spectral Imaging Flow Cytometry
In this article, we describe a method utilizing multi-spectral imaging flow cytometry to quantify the internalization of polyanhydride nanoparticles or bacteria by RAW 264.7 cells.
This protocol details how to quantify synapse number both in dissociated neuronal culture and in brain sections using immunocytochemistry. Using compartment-specific antibodies, we label presynaptic terminals as well as sites of postsynaptic specialization. We define synapses as points of colocalization between the signals generated by these markers.
Imaging Analysis of Neuron to Glia Interaction in Microfluidic Culture Platform (MCP)-based Neuronal Axon and Glia Co-culture System
This study describes the procedures of setting up a novel neuronal axon and (astro)glia co-culture platform. In this co-culture system, manipulation of direct interaction between a single axon (and single glial cell) becomes feasible, allowing mechanistic analysis of the mutual neuron to glial signaling.
We describe a novel surgical method for catheterizing 'intestinal loops' within the ileum of sheep. Once animals have recovered from surgery and have cleared antibiotics and analgesics, multiple treatments can be deposited directly in loops via the catheters.
1Department of Psychiatry, Washington University School of Medicine, 2Department of Anatomy, Washington University School of Medicine, 3Department of Neurobiology, Washington University School of Medicine
Glutamatergic synapses can switch from an active mode to a silent mode. We demonstrate that presynaptic activity status in dissociated culture of rodent neurons is visualized using a fixable form of the FM1-43 dye to visualize active synapses and immunostaining with vGluT-1 antibody to visualize all glutamate synapses.
The localization and distribution of proteins provide important information for understanding their cellular functions. The superior spatial resolution of electron microscopy (EM) can be used to determine the subcellular localization of a given antigen following immunohistochemistry. For tissues of the central nervous system (CNS), preserving structural integrity while maintaining antigenicity has been especially difficult in EM studies. Here, we adopt a procedure that has been used to preserve structures and antigens in the CNS to study and characterize synaptic proteins in rat hippocampal CA1 pyramidal neurons.
The abundance of neurotransmitter receptors clustered at synapses strongly influences synaptic strength. This method quantifies fluorescently-labeled neurotransmitter receptors in three dimensions with single-synapse resolution in C. elegans, allowing hundreds of synapses to be rapidly characterized within a single sample without distortions introduced by z-plane projection.
This video demonstrates the preparation of primary neuronal cultures from the brains of late stage Drosophila pupae. Views of live cultures show neurite outgrowth and imaging of calcium levels using Fura-2.
A Simple and Efficient Method to Isolate Macrophages from Mixed Primary Cultures of Adult Liver Cells
A novel method to obtain macrophages from primary culture of rat liver cells is described. This method utilizes the proliferation of macrophages in the culture, followed by shaking of culture flasks and purification by selective attachment to plastic dishes. This technique efficiently provides liver macrophages without complex equipment and skills.
Postsynaptic Recordings at Afferent Dendrites Contacting Cochlear Inner Hair Cells: Monitoring Multivesicular Release at a Ribbon Synapse
1Department of Otolaryngology-Head and Neck Surgery., The Johns Hopkins School of Medicine, 2Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Consejo Nacional de Investigaciones Científicas y Técnicas
Whole-cell patch-clamp recordings from auditory nerve fiber dendrites at the inner hair cell ribbon synapse in the mammalian cochlea.
Mouse bladder wall injection is a useful approach to orthotopically study bladder stem cell and cancer biology. This delicate microsurgical method can be mastered with careful technique and practice.
Visualizing Cell-to-cell Transfer of HIV using Fluorescent Clones of HIV and Live Confocal Microscopy
1Division of Infectious Diseases, Department of Medicine, Immunology Institute, Mount Sinai School of Medicine, 2NSF Center for Biophotonics, University of California, Davis, 3Structural and Computational Biology Unit, European Molecular Biology Laboratory
This visualized experiment is a guide for utilizing a fluorescent molecular clone of HIV for live confocal imaging experiments.
The Giant Fiber System is a simple neuronal circuit of adult Drosophila melanogaster containing the largest neurons in the fly. We describe the protocol for monitoring synaptic transmission through this pathway by recording post synaptic potentials in dorsal longitudinal (DLM) and tergotrochanteral (TTM) muscles following direct stimulation of the Giant Fiber interneurons.
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.
1Dept. of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, 2Dept. of Biological Chemistry, University of California, Los Angeles, 3Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles
Primary cultures of Aplysia sensory-motor neurons provide a model preparation for studying synapse formation and synaptic plasticity in vitro. This video demonstrates the identification and microdissection of sensory and motor neurons from Aplysia ganglia as well as the methods for establishing and maintaining sensory-motor neurons in culture.
We described structural features of the Glia-neuromuscular synapses in a novel Inside-out tissue preparation of live fly larvae using fluorescent dyes with confocal microscopy. We labeled live neuron terminals with fluorescent primary antibodies to HRP, and also visualized the perisynaptic space with fluorescent Dextrans.
The LookOut Mycoplasma PCR Detection Kit utilizes the polymerase chain reaction (PCR), which is established as the method of choice for highest sensitivity in the detection of Mycoplasma, Acholeplasma, and Ureaplasma contamination in cell cultures and other cell culture derived biologicals.
This protocol describes a reliable method for anesthetization and imaging of intact Drosophila melanogaster larvae. We have utilized the volatile anesthetic desflurane to allow for repetitive imaging at sub-cellular resolution and re-identification of structures for up to a few days1.
Dual Electrophysiological Recordings of Synaptically-evoked Astroglial and Neuronal Responses in Acute Hippocampal Slices
The preparation of acute brain slices from isolated hippocampi, as well as the simultaneous electrophysiological recordings of astrocytes and neurons in stratum radiatum during stimulation of schaffer collaterals is described. The pharmacological isolation of astroglial potassium and glutamate transporter currents is demonstrated.
Preparation of Oligomeric β-amyloid1-42 and Induction of Synaptic Plasticity Impairment on Hippocampal Slices
One feature of Alzheimer's Disease is the elevation of Aβ1-42 peptide. Here we provide a protocol for preparing synthetic Aβ1-42 oligomers, which impairs hippocampal Long-Term Potentiation, a cellular correlate of memory. This procedure is useful for investigating mechanisms of Aβ-induced pathology and drug screening.
The ability to measure the kinetics of vesicle release can help provide insight into some of the basics of neurotransmission. Here we used real-time imaging of vesicles labeled with the red fluorescent dye FM 4-64 to measure the rate of presynaptic vesicle release in hippocampal neuronal cultures.
Transnuclear Mice with Pre-defined T Cell Receptor Specificities Against Toxoplasma gondii Obtained Via SCNT
We demonstrate here that epigenetic reprogramming via Somatic Cell Nuclear Transfer (SCNT) can be used as a tool to generate mouse models with pre-defined T cell receptor (TCR) specificities. These transnuclear mice express the corresponding TCR from their endogenous locus under the control of the endogenous promoter.
This article demonstrates how to conduct electrophysiological recordings of synaptic responses on the extensor muscle in the walking leg of a crayfish and how the nerve terminals are visualized to show the gross morphological differences of high- and low-output nerve terminals.
The neuromuscular junction (NMJ) of Drosophila melanogaster is an important model system for studying normal synaptic function as well as perturbations to synaptic function found in certain neurological diseases. We present a protocol for dissection of the Drosophila larval motor system and immunostaining for active zone proteins within the NMJ.
1Department of Molecular Biology, University of Salzburg, 2Department of Neurology, Paracelsus Medical University, 3Department of Dermatology, Paracelsus Medical University, 4Bühlmann Laboratories, 5Christian Doppler Laboratory for Allergy Diagnosis and Therapy, University of Salzburg
Basophil activation test is a potent tool for the detection of IgE-dependent allergies in vitro. Here, an optimized protocol for basophil activation test is used to investigate drug hypersensitivity. A method for the efficient production of covalent drug-protein conjugates and their physicochemical characterization is described.
We demonstrate how to set up an in vitro ischemia/reperfusion model and how to evaluate the effect of stem cell therapy on postischemic cardiac cells.
Paired Nanoinjection and Electrophysiology Assay to Screen for Bioactivity of Compounds using the Drosophila melanogaster Giant Fiber System
A rapid in vivo assay to test for neuromodulatory compounds using the Giant Fiber System (GFS) of Drosophila melanogaster is described. Nanoinjections in the head of the animal along with electrophysiological recordings of the GFS can reveal bioactivity of compounds on neurons or muscles.
Heterotopic and Orthotopic Tracheal Transplantation in Mice used as Models to Study the Development of Obliterative Airway Disease
This video shows and compares two experimental models to study the development of obliterative airway disease (OAD) in mice, the heterotopic and orthotopic tracheal transplantation model.
The ability of human embryonic stem cells to self-renew and differentiate into all cell types of the body suggests that they hold great promise for both medical applications and as a research tool for addressing fundamental questions in development and disease. Here, we provide a concise, step-by-step protocol for the derivation of human embryonic stem cells from embryos by immunosurgical isolation of the inner cell mass.
Larval zebrafish represent the first vertebrate model system to allow simultaneous patch clamp recording from a spinal motor-neuron and target skeletal muscle. This video demonstrates the microscopic methods used to identify a segmental CaP motor-neuron and target muscle cells as well as the methodologies for recording from each cell type.
The LookOut Mycoplasma elimination kit combines biological agents that reliably and completely eliminate mycoplasma contamination with minimal cytotoxic effect on cells.
A simple protocol for preparing extracts of human tissue to be used as a source of antigens in functional T-cell assays is described. This method allows T-cell responses to tissue-derived antigens to be measured in vitro.
Subcutaneous Administration of Muscarinic Antagonists and Triple-Immunostaining of the Levator Auris Longus Muscle in Mice
1Biology Department, Arcadia University, 2Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, 3Shriners Hospitals Pediatric Research Center and Department of Anatomy and Cell Biology, Temple University School of Medicine
We describe procedures for repeated administration of inhibitors of muscarinic signaling to the levator auris longus (LAL) muscle of young adult mice and for subsequent immunostaining of its neuromuscular junctions (NMJs) in wholemounts. The LAL muscle has unique advantages for revealing in vivo pharmacological effects on NMJs.
Quantitative Analysis of Synaptic Vesicle Pool Replenishment in Cultured Cerebellar Granule Neurons using FM Dyes
A live fluorescence imaging technique to quantify the replenishment and mobilisation of specific synaptic vesicle (SV) pools in central nerve terminals is described. Two rounds of SV recycling are monitored in the same nerve terminals providing an internal control.
Here we describe electrophysiological methods for measuring synaptic transmission at the neuromuscular junction of Drosophila larva. Evoked release is initiated artificially by stimulating the motor neuron axons, and transmission through the NMJ can be measured by the postsynaptic response evoked in the muscle.
Electrophysiological recordings from Drosophila embryos allow analyses of developing muscle and neuron electrical properties, as well as characterization of functional synaptogenesis at the glutamatergic neuromuscular junction and central cholinergic and GABAergic synapses.
This technique exposes the Drosophila embryonic neuromusculature for immunohistochemistry or electrophysiological recording. It is useful for studying early events in neuromuscular development or performing electrophysiology in mutants that cannot hatch.
Microarray analysis was conducted to determine genetic expression profiles in C. elegans, and real-time PCR was used to validate and quantify microarray data.
Simultaneous Pre- and Post-synaptic Electrophysiological Recording from Xenopus Nerve-muscle Co-cultures
This video demonstrates the procedures used to grow primary cultures of embryonic Xenopus nerve and muscle cells and the usefulness of this preparation for making simultaneous pre- and post-synaptic patch clamp recordings.
The frog Xenopus laevis provides an attractive alternative non-mammalian model for exploring the ability of heat shock protein such as gp96 to promote antigen-specific CD8 T cell responses. We present methods to study in vivo facilitation of cross-presentation of skin and tumor antigens by gp96.
Generation and Labeling of Murine Bone Marrow-derived Dendritic Cells with Qdot Nanocrystals for Tracking Studies
1Molecular and Cell Biology Program, Ohio University, 2Department of Biomedical Sciences, College of Osteopathic Medicine, Ohio University, 3Department of Biomedical Engineering, Russ College of Engineering and Technology, Ohio University
Dendritic cells uptake antigens and migrate towards immune organs to present processed antigens to T cells. Qdot nanocrystal labeling provides a long-lasting and stable fluorescent signal. This allows tracking of dendritic cells to different organs by fluorescent microscopy.
Protocols for Vaginal Inoculation and Sample Collection in the Experimental Mouse Model of Candida vaginitis
Key techniques to be used in the evaluation of Candida vaginitis in an experimental animal model are described. The methods will allow rapid collection of vaginal specimens and lymphocytes from draining lumbar lymph nodes. These techniques could give rise to mouse models of other diseases in the female lower genital tract.
1Departments of Pathology and Cell Biology, and Neuroscience, Columbia University College of Physicians and Surgeons, 2Department of Ophthalmology, Columbia University College of Physicians and Surgeons
Here we present two techniques for manipulating gene expression in murine retinal ganglion cells (RGCs) by in utero and ex vivo electroporation. These techniques enable one to examine how alterations in gene expression affect RGC development, axon guidance, and functional properties.
A protocols for an embryonic rat brain aggregate culture system is described. Multipotent progenitors in the aggregates can develop and differentiate into neurons, astrocytes and oligodendrocytes.