Name: measurement of &#947;hv68 infection in mice
Uploaded: 2011-11-22T12:00:00
Description: Watch this Scientific Journal Video about Measurement of Î³HV68 Infection in Mice at JoVE.com

The authors would like to acknowledge the technical advice and support from Ren Sun (University of California, Los Angeles) and Seungmin Hwang (Washington University). This work was funded by the Baxter Foundation, National Institutes of Health grants (R01 CA140964 and R21 AI083841 to C. Liang).

The following protocol will describe the study of virus titers and viral genome loads in the lytic and latent infection cycle of &gamma;HV68 in mice, which can theoretically be used to evaluate infection by other viruses sharing similar lifestyle to that of &gamma;HV68.
1. Amplification of &gamma;HV68
<ol>
	<li>Thaw a frozen vial of &gamma;HV68 in 37 &deg;C water bath.</li>
	<li>Add viral inoculums to NIH3T12 or 3T3 cell culture (~50% confluency) in 10 cm dishes and culture the infected cell...

<ol>
	<li>Damania, B., Choi, J. K., Jung, J. U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Signaling+activities+of+gammaherpesvirus+membrane+proteins.">Signaling activities of gammaherpesvirus membrane proteins.</a> J. Virol. 74, 1593-1601 (2000).</li><li>Stevenson, P. G., Efstathiou, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immune+mechanisms+in+murine+gammaherpesvirus-68+infection.">Immune mechanisms in murine gammaherpesvirus-68 infection.</a> Viral. Immunol. 18, 445-456 (2005).</li><li>Flano, E., Husain, S. M., Sample, J. T., Woodland, D. L., Blackman, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Latent+murine+gamma-herpesvirus+infection+is+established+in+activated+B+cells,+dendritic+cells,+and+macrophages.">Latent murine gamma-herpesvirus infection is established in activated B cells, dendritic cells, and macrophages.</a> J. Immunol. 165, 1074-1081 (2000).</li><li>Sunil-Chandra, N. P., Efstathiou, S., Nash, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Murine+gammaherpesvirus+68+establishes+a+latent+infection+in+mouse+B+lymphocytes+in+vivo.">Murine gammaherpesvirus 68 establishes a latent infection in mouse B lymphocytes in vivo.</a> J. Gen. Virol. 73, 3275-3279 (1992).</li><li>Simas, J. P., Swann, D., Bowden, R., Efstathiou, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+murine+gammaherpesvirus-68+transcription+during+lytic+and+latent+infection.">Analysis of murine gammaherpesvirus-68 transcription during lytic and latent infection.</a> J. Gen. Virol. 80, 75-82 (1999).</li><li>Ganem, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=KSHV+and+the+pathogenesis+of+Kaposi+sarcoma:+listening+to+human+biology+and+medicine.">KSHV and the pathogenesis of Kaposi sarcoma: listening to human biology and medicine.</a> J. Clin. Invest. 120, 939-949 (2010).</li><li>Wen, K. W., Damania, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kaposi+sarcoma-associated+herpesvirus+(KSHV):+molecular+biology+and+oncogenesis.">Kaposi sarcoma-associated herpesvirus (KSHV): molecular biology and oncogenesis.</a> Cancer. Lett. 289, 140-150 (2009).</li><li>E, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Viral+Bcl-2-mediated+evasion+of+autophagy+aids+chronic+infection+of+gammaherpesvirus+68.">Viral Bcl-2-mediated evasion of autophagy aids chronic infection of gammaherpesvirus 68.</a> PLoS. Pathog. 5, e1000609-e1000609 (2009).</li><li>Marques, S., Efstathiou, S., Smith, K. G., Haury, M., Simas, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+gene+expression+of+latent+murine+gammaherpesvirus+68+in+B+lymphocytes.">Selective gene expression of latent murine gammaherpesvirus 68 in B lymphocytes.</a> J. Virol. 77, 7308-7318 (2003).</li><li>McCausland, M. M., Crotty, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+PCR+technique+for+detecting+lymphocytic+choriomeningitis+virus+in+vivo.">Quantitative PCR technique for detecting lymphocytic choriomeningitis virus in vivo.</a> J. Virol. Methods. 147, 167-176 (2008).</li><li>Weck, K. E., Kim, S. S., Virgin, H. I., Speck, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=B+cells+regulate+murine+gammaherpesvirus+68+latency.">B cells regulate murine gammaherpesvirus 68 latency.</a> J. Virol. 73, 4651-4661 (1999).</li><li>Weck, K. E., Kim, S. S., Virgin, H. I., Speck, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophages+are+the+major+reservoir+of+latent+murine+gammaherpesvirus+68+in+peritoneal+cells.">Macrophages are the major reservoir of latent murine gammaherpesvirus 68 in peritoneal cells.</a> J. Virol. 73, 3273-3283 (1999).</li></ol>

&gamma;HV68 has been widely used as a model to understand the pathogenesis of human &gamma;-HVs2,4,5. In this protocol, we described three routinely used methods, including plaque assay for infectious virus titer, IC assay for viral latent load, and qPCR for viral genome load, to evaluate the acute and latent infection of &gamma;HV68 after intranasal inoculation in mice.
The plaque assay has been used extensively to determine the virus titer in infected cells or tissues, but the op...

<table border="1">
	<tbody>
		<tr>
			<td>Material Name</td>
			<td>Preparation Procedure</td>
		</tr>
		<tr>
			<td>Methylcellulose (MC) overlay medium for viral plaque assay</td>
			<td><ol>
			<li>Heat ~ 250 ml of distilled water in TC bottle to &gt; 80&deg;C (boiling for 3 min in microwave)</li>
			<li>Add gradually 2.5 g MC powder into heated water, stirring over low heat until dissolved.</li>
			<li>Autoclave immediately for 15 min at liquid cycle.</li>
			<li>Stirring the autoclaved MC media at 4&deg;C overnight.</li>
			<li>Combine 250 ml MC media with 200ml 2 x MEM (Gibco-BRL) + 50 ml FBS to give 500 ml overlay media. </li>
			</ol></td>
		</tr>
		<tr>
			<td>Fix/stain medium for plaque assay</td>
			<td>0.2% (w/v) crystal violet in 20% ethanol.</td>
		</tr>
		<tr>
			<td>ACK Lysis Buffer</td>
			<td>NH4Cl 0.15M, KHCO3 10mM, EDTA 0.1mM</td>
		</tr>
		<tr>
			<td>Complete DMEM</td>
			<td>Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% fetal bovine serum (FBS; Invitrogen), 2 mM L-glutamine, and 1% penicillin-streptomycin (Gibco-BRL).</td>
		</tr>
	</tbody>
</table>
Table 1. Specific media used in this protocol
<table border="1">
	<tbody>
		<tr>
			<td>Name of the reagent</td>
			<td>Company</td>
			<td>Catalogue number</td>
		</tr>
		<tr>
			<td>Ketamine</td>
			<td>Sigma-Aldrich</td>
			<td>K2753</td>
		</tr>
		<tr>
			<td>Xylazine</td>
			<td>Sigma-Aldrich</td>
			<td>X1251</td>
		</tr>
		<tr>
			<td>Methylcellulose</td>
			<td>Sigma-Aldrich</td>
			<td>M0512-250g</td>
		</tr>
		<tr>
			<td>2 x MEM</td>
			<td>Life Technologies</td>
			<td>11935</td>
		</tr>
		<tr>
			<td>Cell strainer</td>
			<td>BD Faclon</td>
			<td>352340</td>
		</tr>
		<tr>
			<td>Omni tissue homogenizer</td>
			<td>OMNI International</td>
			<td>TH115</td>
		</tr>
		<tr>
			<td>DNeasy Blood & Tissue Kit</td>
			<td>Qiagen</td>
			<td>69504</td>
		</tr>
		<tr>
			<td>iQTM SYBRH Green Supermix</td>
			<td>BioRad</td>
			<td>170-8882</td>
		</tr>
		<tr>
			<td>CFX96 real-time PCR system</td>
			<td>Bio-Rad</td>
			<td>184-5072</td>
		</tr>
		<tr>
			<td>Cell counter</td>
			<td>Bio-Rad</td>
			<td>145-0001</td>
		</tr>
		<tr>
			<td>Sorvall SA-600</td>
			<td>Thermo Scientific</td>
			<td>096-124022</td>
		</tr>
	</tbody>
</table>
Table 2. Specific reagents and equipment

measurement of &#947;hv68 infection in mice

&gamma;-Herpesviruses (&gamma;-HVs) are notable for their ability to establish latent infections of lymphoid cells1. The narrow host range of human &gamma;-HVs, such as EBV and KSHV, has severely hindered detailed pathogenic studies. Murine &gamma;-herpesvirus 68 (&gamma;HV68) shares extensive genetic and biological similarities with human &gamma;-HVs and is a natural pathogen of murid rodents2. As such, evaluation of &gamma;HV68 infection of mice inbred strains at different stages of viral infection provides an important model for understanding viral lifecycle and pathogenesis during &gamma;-HVs infection.
Upon intranasal inoculation, &gamma;HV68 infection results in acute viremia in the lung that is later resolved into a latent infection of splenocytes and other cells, which may be reactivated throughout the life of the host3,4. In this protocol, we will describe how to use the plaque assay to assess infectious virus titer in the lung homogenates on Vero cell monolayers at the early stage (5 - 7 days) of post-intranasal infection (dpi). While acute infection is largely cleared 2 - 3 weeks postinfection, a latent infection of &gamma;HV68 is established around 14 dpi and maintained later on in the spleen of the mice. Latent infection usually affects a very small population of cells in the infected tissues, whereby the virus stays dormant and shuts off most of its gene expression. Latently-infected splenocytes spontaneously reactivate virus upon explanting into tissue culture, which can be recapitulated by an infectious center (IC) assay to determine the viral latent load. To further estimate the amount of viral genome copies in the acutely and/or latently infected tissues, quantitative real-time PCR (qPCR) is used for its maximal sensitivity and accuracy. The combined analyses of the results of qPCR and plaque assay, and/or IC assay will reveal the spatiotemporal profiles of viral replication and infectivity in vivo.

Watch this Scientific Journal Video about Measurement of Î³HV68 Infection in Mice at JoVE.com

Measurement of &#947;HV68 Infection in Mice

&#947;-Herpesviruses (&#947;-HVs) establish life-long persistency in their host. Infection of mice with &#947;-HV68 provides a genetically tractable in vivo model for the characterization of the lifecycle/pathogenesis of &#947;HVs. This protocol describes the detection and quantitation of &#947;HV68 infection at acute and latent stages following infection by plaque-forming, infectious center, and qPCR assays.

&gamma;-Herpesviruses (&gamma;-HVs) are notable for their ability to establish latent infections of lymphoid cells1. The narrow host range of human ...

Research

JoVE Journal

Immunology and Infection

A Method for Labeling Vasculature in Embryonic Mice

The establishment of a functional blood vessel network is an essential part of organogenesis, and is required for optimal organ function. For example, in the thymus proper vasculature formation and patterning is essential for thymocyte entry into the organ and mature T-cell exit to the periphery. The spatial arrangement of blood vessels in the thymus is dependent upon signals from the local microenvironment, namely thymic epithelial cells (TEC). Several recent reports suggest that disruption of these signals results in thymus blood vessel defects 1,2. Previous studies have described techniques used to label the neonatal and adult thymus vasculature 1,2. We demonstrate here a technique for labeling blood vessels in the embryonic thymus. This method combines the use of FITC-dextran or Griffonia (Bandeiraea) Simplicifolia Lectin I (GSL 1 - isolectin B4) facial vein injections and CD31 antibody staining to identify thymus vascular structures and PDGFR-&beta; to label thymic perivascular mesenchyme 3-5. The option of using cryosections or vibratome sections is also provided. This protocol can be used to identify thymus vascular defects, which is critical for defining the roles of TEC-derived molecules in thymus blood vessel formation. As the method labels the entire vasculature, it can also be used to analyze the vascular networks in multiple organs and tissues throughout the embryo including skin and heart 6-10.

This article describes a method for labeling embryonic skin and thymus blood vessels.

The establishment of a functional blood vessel network is an essential part of organogenesis, and is required for optimal organ function. For example, in ...

Measurement of Cytosolic Ca2+ in Isolated Contractile Lymphatics

Lymphatic vessels comprise a multifunctional transport system that maintains fluid homeostasis, delivers lipids to the central circulation, and acts as a surveillance system for potentially harmful antigens, optimizing mucosal immunity and adaptive immune responses1. Lymph is formed from interstitial fluid that enters blind-ended initial lymphatics, and then is transported against a pressure gradient in larger collecting lymphatics. Each collecting lymphatic is made up of a series of segments called lymphangions, separated by bicuspid valves that prevent backflow. Each lymphangion possesses a contractile cycle that propels lymph against a pressure gradient toward the central circulation2. This phasic contractile pattern is analogous to the cardiac cycle, with systolic and diastolic phases, and with a lower contraction frequency4. In addition, lymphatic smooth muscle generates tone and displays myogenic constriction and dilation in response to increases and decreases in luminal pressure, respectively5. A hybrid of molecular mechanisms that support both the phasic and tonic contractility of lymphatics are thus proposed.
Contraction of smooth muscle is generally regulated by the cytosolic Ca2+ concentration ([Ca2+]i) plus sensitivity to Ca2+, of the contractile elements in response to changes in the environment surrounding the cell6. [Ca2+]i is determined by the combination of the movement of Ca2+ through plasma membrane ligand or voltage gated Ca2+ channels and the release and uptake of Ca2+ from internal stores. Cytosolic Ca2+ binds to calmodulin and activates enzymes such as myosin light chain (MLC) kinase (MLCK), which in turn phosphorylates MLC leading to actin-myosin-mediated contraction8. However, the sensitivity of this pathway to Ca2+ can be regulated by the MLC phosphatase (MLCP)9. MLCP activity is regulated by Rho kinase (ROCK) and the myosin phosphatase inhibitor protein CPI-17.
Here, we present a method to evaluate changes in [Ca2+]i over time in isolated, perfused lymphatics in order to study Ca2+-dependent and Ca2+-sensitizing mechanisms of lymphatic smooth muscle contraction. Using isolated rat mesenteric collecting lymphatics we studied stretch-induced changes in [Ca2+]i and contractile activity. The isolated lymphatic model offers the advantage that pressure, flow, and the chemical composition of the bath solution can be tightly controlled. [Ca2+]i was determined by loading lymphatics with the ratiometric, Ca2+-binding dye Fura-2. These studies will provide a new approach to the broader problem of studying the different molecular mechanisms that regulate phasic contractions versus tonic constriction in lymphatic smooth muscle.

Measurement of Cytosolic Ca2+ in Isolated Contractile Lymphatics

We introduce an approach to evaluate the cytosolic Ca2+ concentration in isolated lymphatics to study Ca2+-dependent and Ca2+-sensitizing mechanisms of lymphatic smooth muscle contraction.

Lymphatic vessels comprise a multifunctional transport system that maintains fluid homeostasis, delivers lipids to the central circulation, and acts as a ...

4D Multimodality Imaging of Citrobacter rodentium Infections in Mice

This protocol outlines the steps required to longitudinally monitor a bioluminescent bacterial infection using composite 3D diffuse light imaging tomography with integrated &mu;CT (DLIT-&mu;CT) and the subsequent use of this data to generate a four dimensional (4D) movie of the infection cycle. To develop the 4D infection movies and to validate the DLIT-&mu;CT imaging for bacterial infection studies using an IVIS Spectrum CT, we used infection with bioluminescent C. rodentium, which causes self-limiting colitis in mice. In this protocol, we outline the infection of mice with bioluminescent C. rodentium and non-invasive monitoring of colonization by daily DLIT-&mu;CT imaging and bacterial enumeration from feces for 8 days.
The use of the IVIS Spectrum CT facilitates seamless co-registration of optical and &mu;CT scans using a single imaging platform. The low dose &mu;CT modality enables the imaging of mice at multiple time points during infection, providing detailed anatomical localization of bioluminescent bacterial foci in 3D without causing artifacts from the cumulative radiation. Importantly, the 4D movies of infected mice provide a powerful analytical tool to monitor bacterial colonization dynamics in vivo.

4D Multimodality Imaging of Citrobacter rodentium Infections in Mice

Multi-modality imaging is a valuable approach for studying bacterial colonization in small animal models. This protocol outlines infection of mice with bioluminescent Citrobacter rodentium and the longitudinal monitoring of bacterial colonization using composite 3D diffuse light imaging tomography with &mu;CT imaging to create a 4D movie of C. rodentium infection.

This protocol outlines the steps required to  longitudinally monitor a bioluminescent bacterial infection using composite 3D diffuse light imaging ...

Long Term Chronic Pseudomonas aeruginosa Airway Infection in Mice

A mouse model of chronic airway infection is a key asset in cystic fibrosis (CF) research, although there are a number of concerns regarding the model itself. Early phases of inflammation and infection have been widely studied by using the Pseudomonas aeruginosa agar-beads mouse model, while only few reports have focused on the long-term chronic infection in vivo. The main challenge for long term chronic infection remains the low bacterial burden by P. aeruginosa and the low percentage of infected mice weeks after challenge, indicating that bacterial cells are progressively cleared by the host.
This paper presents a method for obtaining efficient long-term chronic infection in mice. This method is based on the embedding of the P. aeruginosa clinical strains in the agar-beads in vitro, followed by intratracheal instillation in C57Bl/6NCrl mice. Bilateral lung infection is associated with several measurable read-outs including weight loss, mortality, chronic infection, and inflammatory response. The P. aeruginosa RP73 clinical strain was preferred over the PAO1 reference laboratory strain since it resulted in a comparatively lower mortality, more severe lesions, and higher chronic infection. P. aeruginosa colonization may persist in the lung for over three months. Murine lung pathology resembles that of CF patients with advanced chronic pulmonary disease.
This murine model most closely mimics the course of the human disease and can be used both for studies on the pathogenesis and for the evaluation of novel therapies.

Long Term Chronic Pseudomonas aeruginosa Airway Infection in Mice

We describe the agar-beads method to establish persistent long-term chronic Pseudomonas aeruginosa airway infection in the mouse model.

A mouse model of chronic airway infection is a key asset in cystic fibrosis (CF) research, although there are a number of concerns regarding the model ...

Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformans

The polysaccharide capsule of Cryptococcus neoformans is the primary virulence factor and one of the most commonly studied aspects of this pathogenic yeast. Capsule size can vary widely between strains, has the ability to grow rapidly when introduced to stressful or low nutrient conditions, and has been positively correlated with strain virulence. For these reasons, the size of the capsule is of great interest to C. neoformans researchers. The growth of the C. neoformans capsule is induced during phenotypic testing to help understand the effects of different treatments on the yeast or size differences between strains. Here we describe one of the standard methods of capsule induction and compare two accepted methods of staining and measuring capsule diameter: (i) India ink, a negative stain, used in conjunction with conventional light microscopy and (ii) co-staining with fluorescent dyes of both the cell wall and capsule followed by confocal microscopy. Finally, we show how measurement of capsule diameter from India ink-stained samples can be automated using computational image analysis.

Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformans

The polysaccharide capsule is the primary virulence factor in Cryptococcus neoformans, and its size correlates with strain virulence. Capsule diameter measurements are used in phenotypic testing and to gauge therapeutic efficacy. Here a standard method of capsule induction is presented, and two methods of staining and measuring diameter are compared.

The polysaccharide capsule of Cryptococcus neoformans is the primary virulence factor and one of the most commonly studied aspects of this pathogenic ...

A Method for the Measurement of Salivary Gland Function in Mice

Patients with Sj&#246;gren&#39;s syndrome, an autoimmune disease affecting the exocrine glands, develop salivary gland inflammation and have reduced saliva production. Similarly, saliva production is severely compromised in patients receiving radiation treatment for head and neck cancers. Rodent models, developed to mimic these clinical conditions, facilitate an understanding of the disease pathogenesis and allow for the development of new therapeutic strategies. Therefore, the ability to accurately, reproducibly, and repeatedly measure salivary gland function in animal models is critical. Building on procedures previously described in the literature, a method was developed that meets these criteria and was used to evaluate salivary gland function in mice. An additional advantage of this new method is that it is easily mastered, and has little inter-operator variation. Salivary gland function is evaluated as the amount (weight or volume) or rate (mL/min) of saliva produced in response to pilocarpine stimulation. The collected saliva is a good source for the analyses of protein content, immunoglobulin concentrations, and other biomolecules.

Salivary gland hypofunction is a frequent consequence of autoimmune disease and radiation therapy. Reproducible evaluation of salivary gland function in mouse models of these diseases is a technical challenge. Here, a simple method for accurate and reproducible measurement of saliva production in mice is described.

Patients with Sj&#246;gren&#39;s syndrome, an autoimmune disease affecting the exocrine glands, develop salivary gland inflammation and have reduced ...

High-throughput Measurement of Plasma Membrane Resealing Efficiency in Mammalian Cells

In their physiological environment, mammalian cells are often subjected to mechanical and biochemical stresses that result in plasma membrane damage. In response to these damages, complex molecular machineries rapidly reseal the plasma membrane to restore its barrier function and maintain cell survival. Despite 60 years of research in this field, we still lack a thorough understanding of the cell resealing machinery. With the goal of identifying cellular components that control plasma membrane resealing or drugs that can improve resealing, we have developed a fluorescence-based high-throughput assay that measures the plasma membrane resealing efficiency in mammalian cells cultured in microplates. As a model system for plasma membrane damage, cells are exposed to the bacterial pore-forming toxin listeriolysin O (LLO), which forms large 30-50 nm diameter proteinaceous pores in cholesterol-containing membranes. The use of a temperature-controlled multi-mode microplate reader allows for rapid and sensitive spectrofluorometric measurements in combination with brightfield and fluorescence microscopy imaging of living cells. Kinetic analysis of the fluorescence intensity emitted by a membrane impermeant nucleic acid-binding fluorochrome reflects the extent of membrane wounding and resealing at the cell population level, allowing for the calculation of the cell resealing efficiency. Fluorescence microscopy imaging allows for the enumeration of cells, which constitutively express a fluorescent chimera of the nuclear protein histone 2B, in each well of the microplate to account for potential variations in their number and allows for eventual identification of distinct cell populations. This high-throughput assay is a powerful tool expected to expand our understanding of membrane repair mechanisms via screening for host genes or exogenously added compounds that control plasma membrane resealing.

Here we describe a high-throughput fluorescence-based assay that measures the plasma membrane resealing efficiency through fluorometric and imaging analyses in living cells. This assay can be used for screening drugs or target genes that regulate plasma membrane resealing in mammalian cells.

In their physiological environment, mammalian cells are often subjected to mechanical and biochemical stresses that result in plasma membrane damage. In ...

Evaluation of Host-Pathogen Responses and Vaccine Efficacy in Mice

Vaccines are a 20th century medical marvel. They have dramatically reduced the morbidity and mortality caused by infectious diseases and contributed to a striking increase in life expectancy around the globe. Nonetheless, determining vaccine efficacy remains a challenge. Emerging evidence suggests that the current acellular vaccine (aPV) for Bordetella pertussis (B. pertussis) induces suboptimal immunity. Therefore, a major challenge is designing a next-generation vaccine that induces protective immunity without the adverse side effects of a whole-cell vaccine (wPV). Here we describe a protocol that we used to test the efficacy of a promising, novel adjuvant that skews immune responses to a protective Th1/Th17 phenotype and promotes a better clearance of a B. pertussis challenge from the murine respiratory tract. This article describes the protocol for mouse immunization, bacterial inoculation, tissue harvesting, and analysis of immune responses. Using this method, within our model, we have successfully elucidated crucial mechanisms elicited by a promising, next-generation acellular pertussis vaccine. This method can be applied to any infectious disease model in order to determine vaccine efficacy.

Here we present an elegant protocol for in vivo evaluation of vaccine effectiveness and host immune responses. This protocol can be adapted for vaccine models that study viral, bacterial, or parasitic pathogens.

Vaccines are a 20th century medical marvel. They have dramatically reduced the morbidity and mortality caused by infectious diseases and contributed to a ...

Measurement of Chitinase Activity in Biological Samples

Chitinases are the enzymes that cleave chitin. Even in the absence of chitin, mammalians have significant amounts of chitinases present in the body including at baseline. The precise role of chitinase is not known, however it was believed to play important role in digestion and host defense against chitin-containing food and pathogens, respectively. Recent work, including ours, has shown an important role of chitinase and chitinase-like proteins in host immunity and allergic diseases. Importantly, chitinase activities serve as important biomarkers of disease severity in a wide-range of diseases including type 2 inflammatory diseases such as asthma and pulmonary fibrosis. Similarly, patients with genetic disorders like Gaucher disease have significantly elevated chitinase levels, which not only correlate with disease severity but also serve as a reliable biomarker for therapeutic effectiveness. The protocol outlined here describes a simple, quick, and straightforward way to measure chitinase activity in BAL or serum samples of mice and can be widely adapted to human subjects and other model organisms due to the highly conserved nature of the enzymes.

Presented here is a simple method to measure chitinase activity in biological fluids such as bronchoalveolar lavage or serum.

Chitinases are the enzymes that cleave chitin. Even in the absence of chitin, mammalians have significant amounts of chitinases present in the body ...

Evaluation of T Follicular Helper Cells and Germinal Center Response During Influenza A Virus Infection in Mice

T Follicular Helper (Tfh) cells are an independent CD4+&#160;T cell subset specialized in providing help for germinal center (GC) development and generation of high-affinity antibodies. In influenza virus infection, robust Tfh and GC B cell responses are induced to facilitate effective virus eradication, which confers a qualified mouse model for Tfh-associated study. In this paper, we described protocols in detection of basic Tfh-associated immune response during influenza virus infection in mice. These protocols include: intranasal inoculation of influenza virus; flow cytometry staining and analysis of polyclonal and antigen-specific Tfh cells, GC B cells and plasma cells; immunofluorescence detection of GCs; enzyme-linked immunosorbent assay (ELISA) of influenza virus-specific antibody in serum. These assays basically quantify the differentiation and function of Tfh cells in influenza virus infection, thus providing help for studies in elucidating differentiation mechanism and manipulation strategy.

This paper describes protocols of evaluating Tfh and GC B response in mouse model of influenza virus infection.