这项研究是由威康信托高级奖学金颁发给伊恩·古德费洛，1居里夫人内欧洲奖学金（欧盟第七框架计划的欧洲研究理事会）授予阿曼多·阿里亚斯。我们要感谢给我们权限，使用安捷伦bioanalyser，帮助运行的RNA样品木卫一香港昌博士丽贝卡罗比和迈克·斯金纳博士。

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W., Wimmer, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cap-independent+translation+of+picornavirus+RNAs:+structure+and+function+of+the+internal+ribosomal+entry+site.">Cap-independent translation of picornavirus RNAs: structure and function of the internal ribosomal entry site.</a> Enzyme. 44, 292-309 (1990).</li><li>Chaudhry, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Caliciviruses+differ+in+their+functional+requirements+for+eIF4F+components.">Caliciviruses differ in their functional requirements for eIF4F components.</a> J. Biol. Chem. 281, 25315-25325 (2006).</li><li>Goodfellow, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calicivirus+translation+initiation+requires+an+interaction+between+VPg+and+eIF+4.">Calicivirus translation initiation requires an interaction between VPg and eIF 4.</a> E. EMBO Rep. 6, 968-972 (2005).</li><li>Herbert, T. P., Brierley, I., Brown, T. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+a+protein+linked+to+the+genomic+and+subgenomic+mRNAs+of+feline+calicivirus+and+its+role+in+translation.">Identification of a protein linked to the genomic and subgenomic mRNAs of feline calicivirus and its role in translation.</a> J. Gen. Virol. 78 ( Pt5 ), 1033-1040 (1997).</li><li>Chaudhry, Y., Skinner, M. A., Goodfellow, I. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recovery+of+genetically+defined+murine+norovirus+in+tissue+culture+by+using+a+fowlpox+virus+expressing+T7+RNA+polymerase.">Recovery of genetically defined murine norovirus in tissue culture by using a fowlpox virus expressing T7 RNA polymerase.</a> J. Gen. Virol. 88, 2091-20100 (2007).</li><li>Ward, V. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recovery+of+infectious+murine+norovirus+using+pol+II-driven+expression+of+full-length+cDNA.">Recovery of infectious murine norovirus using pol II-driven expression of full-length cDNA.</a> Proc. Natl. Acad. Sci. U.S.A. 104, 11050-11055 (2007).</li><li>Yunus, M. A., Chung, L. M., Chaudhry, Y., Bailey, D., Goodfellow, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+an+optimized+RNA-based+murine+norovirus+reverse+genetics+system.">Development of an optimized RNA-based murine norovirus reverse genetics system.</a> J. Virol. Methods. 169, 112-118 (2010).</li><li>Arias, A., Perales, C., Escarmis, C., Domingo, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deletion+mutants+of+VPg+reveal+new+cytopathology+determinants+in+a+picornavirus.">Deletion mutants of VPg reveal new cytopathology determinants in a picornavirus.</a> PLoS One. 5, e10735 (2010).</li><li>Werf, S. v. a. n. d. e. r., Bradley, J., Wimmer, E., Studier, F. W., Dunn, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+infectious+poliovirus+RNA+by+purified+T7+RNA+polymerase.">Synthesis of infectious poliovirus RNA by purified T7 RNA polymerase.</a> Proc. Natl. Acad. Sci. U.S.A. 83, 2330-2334 (1986).</li><li>Bailey, D., Thackray, L. B., Goodfellow, I. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+single+amino+acid+substitution+in+the+murine+norovirus+capsid+protein+is+sufficient+for+attenuation+in+vivo.">A single amino acid substitution in the murine norovirus capsid protein is sufficient for attenuation in vivo.</a> J. Virol. 82, 7725-7728 (2008).</li><li>Bailey, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+analysis+of+RNA+structures+present+at+the+3'+extremity+of+the+murine+norovirus+genome:+the+variable+polypyrimidine+tract+plays+a+role+in+viral+virulence.">Functional analysis of RNA structures present at the 3' extremity of the murine norovirus genome: the variable polypyrimidine tract plays a role in viral virulence.</a> J. Virol. 84, 2859-2870 (2010).</li></ol>

我们什么都没有透露。

在这里，我们已经说明了两个不同的反向遗传学的方法，允许在细胞培养感染MNV恢复。这两种方法都有效地绕过为VPG通过代细胞的核糖体，然后由公认的皑皑MNV成绩单病毒RNA基因的5&#39;端共价联动的绝对要求。是更有效地在体外转录酶封顶传染病MNV转录比传染病质粒在细胞表达T7 RNA聚合酶的成绩单，其中可上限由鸡痘病毒封盖酶恢复。与这些反向遗传系统恢复病毒滴度类似VPG联病毒感染的细胞培养17（ 图5）纯化的RNA转染获得这些。皑皑MNV RNA进入许可Raw264.7细胞的转染呈现比实验涉及的transfectio的病毒滴度较低只有1日志N含有病毒的VPG联的RNA（ 图5）感染的细胞的总RNA。这实际上鼓励了进一步的调查，以确定是否可能导致病毒产量的增加，这可能揭示VPG相关的细胞的基本功能方面MNV传染性的VPG分子除了5&#39;这些系统所产生的最终成绩单。尽管如此，我们认为这种反向遗传学系统作为一种高效，与其他RNA病毒反向遗传学系统目前使用的体外转录RNA滴度只有真正感染病毒颗粒19，20比10-100允许恢复。 总体而言，目前的方法构成了诺罗病毒分子生物学领域的重要一步和提供的工具，我们调查的职能作用的蛋白质和诺罗病毒基因组保守的RNA图案。这些方法已经与C的结合urrent小鼠模型，并已显示出MNV传染性cDNA的恢复是能够引起致命感染- &gt; 80％STAT1的/小鼠在不到10天4，21。利用这一点，我们已经恢复了可行小鼠诺沃克病毒突变的衣壳蛋白和参与结合不同的宿主因素（PTB和选票详情规例）显示，在体内 21，22有点减毒表型的polypyrimidine道系统。此外，我们最近已表明，病毒缺乏表达能力从ORF4 VF1蛋白在细胞培养中有效地复制，但再次减少为WT MNV 8小鼠的毒性。这些研究，鼓励我们设计人类诺如病毒的减毒MNV可作为潜在的候选疫苗调查研究的基础版本。

<table border="1"><tbody><tr><td> 试剂名称 </td><td> 公司 </td><td> 目录编号 </td></tr><tr><td>氯化锂沉淀解决方案</td><td> Ambion公司</td><td> AM9480 </td></tr><tr><td> RNA的存储解决方案</td><td> Ambion公司</td><td> AM7000 </td></tr><tr><td> MEGAscript T7启动脚本</td><td> Ambion公司</td><td> AM1333 </td></tr><tr><td> ScriptCap m7G旋盖系统</td><td>震中生物技术</td><td> SCCE0610 </td></tr><tr><td>霓虹灯转染系统</td><td> Invitrogen公司</td><td> MPK5000 </td></tr><tr><td>霓虹灯转染系统套件</td><td> Invitrogen公司</td><td> MPK1025 </td></tr><tr><td> OPTI-MEM我</td><td> Invitrogen公司</td><td> 31985070 </td></tr><tr><td>脂质体2000转染试剂</td><td> Invitrogen公司</td><td> 11668-027 </td></tr><tr><td>安捷伦RNA的600纳米套件</td><td>安捷伦</td><td> 5067-1511 </td></tr><tr><td>安捷伦2100 BIoanalyzer </td><td>安捷伦</td><td> G2939AA </td></tr><tr><td>插图GFX总DNA和凝胶带纯化试剂盒</td><td> GE医疗集团</td><td> 28-9034-70 </td></tr><tr><td> RiboMAX大规模RNA生产系统-T7 </td><td> Promega公司</td><td> P1300 </td></tr></tbody></table>

reverse genetics mediated recovery of infectious murine norovirus

人类诺如病毒是人类胃肠炎（GE）全球大多数情况下，负责，并在那里亲近的人对人的接触是无法避免的，1，2的环境中经常出现的问题。在医院暴发的发病率增加，在过去几年中已有报道，造成重大影响自身的业务能力以及巨大的经济损失。由于人类诺如病毒无法完成生产感染的细胞培养3，确定新的抗病毒方法已经被限制。小鼠诺沃克病毒（MNV）密切相关的人类诺罗病毒，但最近的隔离可在细胞5传播开辟了调查这些病原体6，7的新途径。 在新的积极意义的基因组和亚基因组RNA分子的合成的MNV复制结果，其中后者对应到最后THI病毒基因组的路（ 图1）。 MNV包含四个不同的开放阅读框（ORF），其中ORF1基因占据大部分的基因组，编码7个非结构蛋白（NS1蛋白-7）释放由聚易制毒化学。载的ORF2和ORF3内的亚基因组RNA地区和编码衣壳蛋白（VP1和VP2），分别为（ 图1）。最近，我们已经确定了额外的ORF4重叠的ORF2，但在不同的阅读框的功能和线粒体的本地化的致病因子（VF1）8编码。 积极意义的RNA病毒，包括诺如病毒，复制发生在细胞质中造成新的不封顶的RNA基因组的合成。促进翻译病毒，病毒利用不同的策略，旨在招聘细胞的蛋白质合成机器9-11。有趣的是，诺罗病毒的翻译是由多功能的病毒蛋白底漆VPG共价连接到5月底的两个基因组和亚基因组RNA 12-14。这种翻译复杂的机制很可能是在有限的病毒恢复传统的反向遗传学方法效率的主要因素。 在这里，我们报告两个不同的策略，基于上一代小鼠诺罗-1（简称MNV谨）在5&#39;端上限的成绩单。的方法之一，涉及体外病毒RNA的合成和封盖，而第二种方法需要的MNV细胞表达T7 RNA聚合酶基因的转录。这些反向遗传学的的MNV研究和小动物模型系统的可用性提供了一个前所未有的能力，解剖病毒复制和发病机制15-17序列的作用。

Watch this Scientific Journal Video about Reverse Genetics Mediated Recovery of Infectious Murine Norovirus at JoVE.com

Reverse Genetics Mediated Recovery of Infectious Murine Norovirus

诺如病毒肠胃炎尚未分子技术是表征的主要原因仍然是相对较新的。在这里，我们报告两个不同的反向遗传学方法对小鼠诺沃克病毒（MNV），本属的唯一成员，可在细胞培养繁殖的高效回收。

反向遗传学感染小鼠诺沃克病毒介导的恢复

Human noroviruses are responsible for most cases of human gastroenteritis (GE) worldwide and are recurrent problem in environments where close ...

reverse-genetics-mediated-recovery-of-infectious-murine-norovirus

Research

JoVE Journal

Immunology and Infection

16.5K 次观看.  Imperial College London. 诺如病毒肠胃炎尚未分子技术是表征的主要原因仍然是相对较新的。在这里，我们报告两个不同的反向遗传学方法对小鼠诺沃克病毒（MNV），本属的唯一成员，可在细胞培养繁殖的高效回收。

视频: Reverse Genetics Mediated Recovery of Infectious Murine Norovirus

Using Reverse Genetics to Manipulate the NSs Gene of the Rift Valley Fever Virus MP-12 Strain to Improve Vaccine Safety and Efficacy

Rift Valley fever virus (RVFV), which causes hemorrhagic fever, neurological disorders or blindness in humans, and a high rate abortion and fetal malformation in ruminants1, has been classified as a HHS/USDA overlap select agent and a risk group 3 pathogen. It belongs to the genus Phlebovirus in the family Bunyaviridae and is one of the most virulent members of this family. Several reverse genetics systems for the RVFV MP-12 vaccine strain2,3 as well as wild-type RVFV strains 4-6, including ZH548 and ZH501, have been developed since 2006. The MP-12 strain (which is a risk group 2 pathogen and a non-select agent) is highly attenuated by several mutations in its M- and L-segments, but still carries virulent S-segment RNA3, which encodes a functional virulence factor, NSs. The rMP12-C13type (C13type) carrying 69% in-frame deletion of NSs ORF lacks all the known NSs functions, while it replicates as efficient as does MP-12 in VeroE6 cells lacking type-I IFN. NSs induces a shut-off of host transcription including interferon (IFN)-beta mRNA7,8 and promotes degradation of double-stranded RNA-dependent protein kinase (PKR) at the post-translational level.9,10 IFN-beta is transcriptionally upregulated by interferon regulatory factor 3 (IRF-3), NF-kB and activator protein-1 (AP-1), and the binding of IFN-beta to IFN-alpha/beta receptor (IFNAR) stimulates the transcription of IFN-alpha genes or other interferon stimulated genes (ISGs)11, which induces host antiviral activities, whereas host transcription suppression including IFN-beta gene by NSs prevents the gene upregulations of those ISGs in response to viral replication although IRF-3, NF-kB and activator protein-1 (AP-1) can be activated by RVFV7. . Thus, NSs is an excellent target to further attenuate MP-12, and to enhance host innate immune responses by abolishing the IFN-beta suppression function. Here, we describe a protocol for generating a recombinant MP-12 encoding mutated NSs, and provide an example of a screening method to identify NSs mutants lacking the function to suppress IFN-beta mRNA synthesis. In addition to its essential role in innate immunity, type-I IFN is important for the maturation of dendritic cells and the induction of an adaptive immune response12-14. Thus, NSs mutants inducing type-I IFN are further attenuated, but at the same time are more efficient at stimulating host immune responses than wild-type MP-12, which makes them ideal candidates for vaccination approaches.

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.

利用反向遗传学操作的裂谷热病毒MP - 12菌株，以提高疫苗的安全性和有效性的NSS基因

Rift Valley fever virus (RVFV), which causes hemorrhagic fever, neurological disorders or blindness in humans, and a high rate abortion and fetal ...

科研

免疫与感染

Plaque Assay for Murine Norovirus

Murine norovirus (MNV) is the only member of the Norovirus genus that efficiently grows in tissue culture 1, 2. Cell lysis and cytopathic effect (CPE) are observed during MNV-1 infection of murine dendritic cells or macrophages 1. This property of MNV-1 can be used to quantify the number of infectious particles in a given sample by performing a plaque assay 1. The plaque assay relies on the ability of MNV-1 to lyse cells and to form holes in a confluent cell monolayer, which are called plaques 3.
Multiple techniques can be used to detect viral infections in tissue culture, harvested tissue, clinical, and environmental samples, but not all measure the number of infectious particles (e.g. qRT-PCR). One way to quantify infectious viral particles is to perform a plaque assay 3, which will be described in detail below. A variation on the MNV plaque assay is the fluorescent focus assay, where MNV antigen is immunostained in cell monolayers 4. This assay can be faster, since viral antigen expression precedes plaque formation. It is also useful for titrating viruses unable to form plaques. However, the fluorescent focus assay requires additional resources beyond those of the plaque assay, such as antibodies and a microscope to count focus-forming units. Infectious MNV can also be quantified by determining the 50% Tissue Culture Infective Dose (TCID50) 3. This assay measures the amount of virus required to produce CPE in 50% of inoculated tissue culture cells by endpoint titration 5. However, its limit of detection is higher compared to a plaque assay 4.
In this article, we describe a plaque assay protocol that can be used to effectively determine the number of infectious MNV particles present in biological or environmental samples 1, 4, 6. This method is based on the preparation of 10-fold serial dilutions of MNV-containing samples, which are used to inoculate a monolayer of permissive cells (RAW 264.7 murine macrophage cells). Virus is allowed to attach to the cell monolayer for a given period of time and then aspirated before covering cells with a mixture of agarose and cell culture media. The agar enables the spread of viral progeny to neighboring cells while limiting spread to distantly located cells. Consequently, infected cells are lysed and form holes in the monolayer known as plaques. Upon sufficient spread of virus, plaques become visible following staining of cells with dyes, like neutral red, methylene blue, or crystal violet. At low dilutions, each plaque originates from one infectious viral particle and its progeny, which spread to neighboring cells. Thus, counting the number of plaques allows one to calculate plaque-forming units (PFU) present in the undiluted sample 3.

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&#x2019;s tropism for murine macrophages and can be adapted for use with biological or environmental samples containing MNV.

对小鼠诺沃克类病毒的空斑法

Murine norovirus (MNV) is the only member of the Norovirus genus that efficiently grows in tissue culture 1, 2. Cell lysis and cytopathic effect (CPE) are ...

Isolating And Immunostaining Lymphocytes and Dendritic Cells from Murine Peyer's Patches

Peyer's patches (PPs) are integral components of the gut-associated lymphoid tissues (GALT) and play a central role in intestinal immunosurveillance and homeostasis. Particulate antigens and microbes in the intestinal lumen are continuously sampled by PP M cells in the follicle-associated epithelium (FAE) and transported to an underlying network of dendritic cells (DCs), macrophages, and lymphocytes. In this article, we describe protocols in which murine PPs are (i) dissociated into single cell suspensions and subjected to flow cytometry and (ii) prepared for cryosectioning and immunostaining. For flow cytometry, PPs are mechanically dissociated and then filtered through 70 &mu;m membranes to generate single cell suspensions free of epithelial cells and large debris. Starting with 20-25 PPs (from four mice), this quick and reproducible method yields a population of &gt;2.5 x 106 cells with &gt;90% cell viability. For cryosectioning, freshly isolated PPs are immersed in Optimal Cutting Temperature (OCT) medium, snap-frozen in liquid nitrogen, and then sectioned using a cryomicrotome. Tissue sections (5-12 &mu;m) are air-dried, fixed with acetone or methanol, and then subjected to immunolabeling.

Isolating And Immunostaining Lymphocytes and Dendritic Cells from Murine Peyer&#039;s Patches

There is an increasing interest in understanding the immunological functions of specific subpopulations of cells in Peyer's patches (PPs), the primary inductive sites of gut-associated lymphoid tissues. Here we outline parallel protocols for preparing PP single cell preparations for flow cytometric analysis and PP cryosections for immunostaining.

隔离和免疫淋巴细胞和树突状细胞的小鼠Peyer氏斑

Peyer's  patches (PPs) are integral components of the gut-associated lymphoid tissues  (GALT) and play a central role in intestinal immunosurveillance and ...

VIGS-Mediated Forward Genetics Screening for Identification of Genes Involved in Nonhost Resistance

Nonhost disease resistance of plants against bacterial pathogens is controlled by complex defense pathways. Understanding this mechanism is important for developing durable disease-resistant plants against wide range of pathogens. Virus-induced gene silencing (VIGS)-based forward genetics screening is a useful approach for identification of plant defense genes imparting nonhost resistance. Tobacco rattle virus (TRV)-based VIGS vector is the most efficient VIGS vector to date and has been efficiently used to silence endogenous target genes in Nicotiana benthamiana.

	In this manuscript, we demonstrate a forward genetics screening approach for silencing of individual clones from a cDNA library in N. benthamiana and assessing the response of gene silenced plants for compromised nonhost resistance against nonhost pathogens, Pseudomonas syringae pv. tomato T1, P. syringae pv. glycinea, and X. campestris pv. vesicatoria. These bacterial pathogens are engineered to express GFPuv protein and their green fluorescing colonies can be seen by naked eye under UV light in the nonhost pathogen inoculated plants if the silenced target gene is involved in imparting nonhost resistance. This facilitates reliable and faster identification of gene silenced plants susceptible to nonhost pathogens. Further, promising candidate gene information can be known by sequencing the plant gene insert in TRV vector. Here we demonstrate the high throughput capability of VIGS-mediated forward genetics to identify genes involved in nonhost resistance. Approximately, 100 cDNAs can be individually silenced in about two to three weeks and their relevance in nonhost resistance against several nonhost bacterial pathogens can be studied in a week thereafter. In this manuscript, we enumerate the detailed steps involved in this screening. VIGS-mediated forward genetics screening approach can be extended not only to identifying genes involved in nonhost resistance but also to studying genes imparting several biotic and abiotic stress tolerances in various plant species.

Virus-induced gene silencing is an useful tool for identifying genes involved in nonhost resistance of plants. We demonstrate the use of bacterial pathogens expressing GFPuv in identifying gene silenced plants susceptible to nonhost pathogens. This approach is easy, fast and facilitates large scale screening and similar protocol can be applied to studying various other plant-microbe interactions.

VIGS介导的正向遗传学筛选参与非寄主抗性基因鉴定


	Nonhost disease resistance of plants against bacterial pathogens is controlled by complex defense pathways. Understanding this mechanism is important ...

Organoids as Model for Infectious Diseases: Culture of Human and Murine Stomach Organoids and Microinjection of Helicobacter Pylori

Recently infection biologists have employed stem cell derived cultures to answer the need for new and better models to study host-pathogen interactions. Three cellular sources have been used: Embryonic stem cells (ESC), induced pluripotent stem cells (iPSC) or adult stem cells. Here, culture of mouse and human gastric organoids derived from adult stem cells is described and used for infection with the gastric pathogen Helicobacter pylori. Human gastric glands are isolated from resection material, seeded in a basement matrix and embedded in medium containing growth factors epidermal growth factor (EGF), R-spondin, Noggin, Wnt, fibroblast growth factor (FGF) 10, gastrin and transforming growth factor (TGF) beta inhibitor. In these conditions, gastric glands grow into 3-dimensional organoids containing 4 lineages of the stomach. The organoids expand indefinitely and can be frozen and thawed similarly as cell lines. For infection studies, bacteria are microinjected into the lumen of the organoids. Infected organoids are processed for imaging. The described methods can be adapted to other organoids and infections with other bacteria, viruses or parasites. This allows the study of infection-induced changes in primary cells.

Stem cell derived cultures harbor tremendous potential to model infectious diseases. Here, the culture of mouse and human gastric organoids derived from adult stem cells is described. The organoids are microinjected with the gastric pathogen Helicobacter pylori.

类器官的模型传染病:人类的文化与小鼠胃组织体与幽门螺杆菌的显微注射

Recently infection biologists have employed stem cell derived cultures to answer the need for new and better models to study host-pathogen interactions. ...

Isolation and Flow Cytometric Characterization of Murine Small Intestinal Lymphocytes

The intestines &#8212; which contain the largest number of immune cells of any organ in the body &#8212; are constantly exposed to foreign antigens, both microbial and dietary. Given an increasing understanding that these luminal antigens help shape the immune response and that education of immune cells within the intestine is critical for a number of systemic diseases, there has been increased interest in characterizing the intestinal immune system. However, many published protocols are arduous and time-consuming. We present here a simplified protocol for the isolation of lymphocytes from the small-intestinal lamina propria, intraepithelial layer, and Peyer&#39;s patches that is rapid, reproducible, and does not require laborious Percoll gradients. Although the protocol focuses on the small intestine, it is also suitable for analysis of the colon. Moreover, we highlight some aspects that may need additional optimization depending on the specific scientific question. This approach results in the isolation of large numbers of viable lymphocytes that can subsequently be used for flow cytometric analysis or alternate means of characterization.

There is growing interest in the quantitative characterization of intestinal lymphocytes owing to increasing recognition that these cells play a critical role in a variety of intestinal and systemic diseases. In this protocol, we describe how to isolate single cell populations from different small-intestinal compartments for subsequent flow cytometric characterization.

小鼠小肠淋巴细胞的分离和流式细胞表征

The intestines &#8212; which contain the largest number of immune cells of any organ in the body &#8212; are constantly exposed to foreign antigens, both ...

Swab Sampling Method for the Detection of Human Norovirus on Surfaces

Human noroviruses are a leading cause of epidemic and sporadic gastroenteritis worldwide. Because most infections are either spread directly via the person-to-person route or indirectly through environmental surfaces or food, contaminated fomites and inanimate surfaces are important vehicles for the spread of the virus during norovirus outbreaks.
We developed and evaluated a protocol using macrofoam swabs for the detection and typing of human noroviruses from hard surfaces. Compared with fiber-tipped swabs or antistatic wipes, macrofoam swabs allow virus recovery (range 1.2-33.6%) from toilet seat surfaces of up to 700 cm2. The protocol includes steps for the extraction of the virus from the swabs and further concentration of the viral RNA using spin columns. In total, 127 (58.5%) of 217 swab samples that had been collected from surfaces in cruise ships and long-term care facilities where norovirus gastroenteritis had been reported tested positive for GII norovirus by RT-qPCR. Of these 29 (22.8%) could be successfully genotyped. In conclusion, detection of norovirus on environmental surfaces using the protocol we developed may assist in determining the level of environmental contamination during outbreaks as well as detection of virus when clinical samples are not available; it may also facilitate monitoring of effectiveness of remediation strategies.

A macrofoam based sampling methodology was developed and evaluated for the detection and quantification of norovirus on environmental hard surfaces.

人类诺沃克病毒的表面上检测拭子采样方法

Human noroviruses are a leading cause of epidemic and sporadic gastroenteritis worldwide. Because most infections are either spread directly via the ...

A Method to Assess Fc-mediated Effector Functions Induced by Influenza Hemagglutinin Specific Antibodies

Antibodies play a crucial role in coupling the innate and adaptive immune responses against viral pathogens through their antigen binding domains and Fc-regions. Here, we describe how to measure the activation of Fc effector functions by monoclonal antibodies targeting the influenza virus hemagglutinin with the use of a genetically engineered Jurkat cell line expressing an activating type 1 Fc-Fc&#947;R. Using this method, the contribution of specific Fc-Fc&#947;R interactions conferred by immunoglobulins can be determined using an in vitro assay.

We describe a method to measure the activation of Fc-mediated effector functions by antibodies that target the influenza virus hemagglutinin. This assay can also be adapted to assess the ability of monoclonal antibodies or polyclonal sera targeting other viral surface glycoproteins to induce Fc-mediated immunity.

流感血凝素特异抗体诱导的 Fc 介导效应函数的一种评估方法

Antibodies play a crucial role in coupling the innate and adaptive immune responses against viral pathogens through their antigen binding domains and ...

Isolating Lymphocytes from the Mouse Small Intestinal Immune System

The intestinal immune system plays an essential role in maintaining the barrier function of the gastrointestinal tract by generating tolerant responses to dietary antigens and commensal bacteria while mounting effective immune responses to enteropathogenic microbes. In addition, it has become clear that local intestinal immunity has a profound impact on distant and systemic immunity. Therefore, it is important to study how an intestinal immune response is induced and what the immunologic outcome of the response is. Here, a detailed protocol is described for the isolation of lymphocytes from small intestine inductive sites like the gut-associated lymphoid tissue Peyer&#39;s patches and the draining mesenteric lymph nodes and effector sites like the lamina propria and the intestinal epithelium. This technique ensures isolation of a large numbers of lymphocytes from small intestinal tissues with optimal purity and viability and minimal cross compartmental contamination within acceptable time constraints. The technical capability to isolate lymphocytes and other immune cells from intestinal tissues enables the understanding of immune responses to gastrointestinal infections, cancers, and inflammatory diseases.

Here we describe a detailed protocol for the isolation of lymphocytes from the inductive sites including the gut-associated lymphoid tissue Peyer&#39;s patches and the draining mesenteric lymph nodes, and the effector sites including the lamina propria and the intestinal epithelium of the small intestinal immune system.

小鼠小肠免疫系统淋巴细胞的分离

The intestinal immune system plays an essential role in maintaining the barrier function of the gastrointestinal tract by generating tolerant responses to ...

Preparation of Murine Submandibular Salivary Gland for Upright Intravital Microscopy

The submandibular salivary gland (SMG) is one of the three major salivary glands, and is of interest for many different fields of biological research, including cell biology, oncology, dentistry, and immunology. The SMG is an exocrine gland comprised of secretory epithelial cells, myofibroblasts, endothelial cells, nerves, and extracellular matrix. Dynamic cellular processes in the rat and mouse SMG have previously been imaged, mostly using inverted multi-photon microscope systems. Here, we describe a straightforward protocol for the surgical preparation and stabilization of the murine SMG in anesthetized mice for in vivo imaging with upright multi-photon microscope systems. We present representative intravital image sets of endogenous and adoptively transferred fluorescent cells, including the labeling of blood vessels or salivary ducts and second harmonic generation to visualize fibrillar collagen. In sum, our protocol allows for surgical preparation of mouse salivary glands in upright microscopy systems, which are commonly used for intravital imaging in the field of immunology.

We describe a protocol to surgically expose and stabilize the murine submandibular salivary gland for intravital imaging using upright intravital microscopy. This protocol is easily adaptable to other exocrine glands of the head and neck region of mice and other small rodents.

直立活体显微术制备小鼠颌下腺涎腺

The submandibular salivary gland (SMG) is one of the three major salivary glands, and is of interest for many different fields of biological research, ...