我们感谢博士戴安娜Baronas洛厄尔的手稿的批判性阅读。这项工作得到了科学种子格兰特的FAU查尔斯·E·施密特学院，并从埃利森医学基金会的老化奖学金KJ支持

1，XLD（木糖赖氨酸去氧胆酸盐）琼脂平板 XLD琼脂是沙门氏菌，这似乎是在XLD琼脂平板上菌落黑色选择性生长培养基。然而，如果有污染的担忧，一个普通的LB板可以被取代。 <ol><li>称取5毫升去离子水5.5克XLD琼脂和重悬。 </li><li>调匀，直到所有的琼脂是湿的。添加95毫升去离子水，直到所有肿块消失，介质完全悬浮。 </li><li>熬中期至完全溶解（不要高压灭菌）。 </li><li>冷却介质在室温至50℃。 </li><li>倒25毫升琼脂中的每个95×15毫米（直径×高度）板（用封口膜密封板可以储存在4℃可保存1个月）。 </li></ol> 2，线虫生长培养基（NGM）的RNAi喂养板 C.编制线虫 NGM板先前已描述19，这里的过程简要描述以添加抗生素氨苄青霉素和RNAi的化学诱导物异丙基-β-D-1-硫代半乳糖苷（IPTG）到NGM媒体，使RNAi的馈送板。 <ol><li>将3克氯化钠和2.5克细菌蛋白胨于1升去离子水。 </li><li>添加17克细菌用琼脂到媒体。 </li><li>高压灭菌的培养基45分钟，并在水浴中冷却介质到50°C。 </li><li>添加下列溶液：1毫升胆固醇（5毫克/毫升的95％乙醇），将1ml的1M的CaCl 2，加入1ml 1M的MgSO 4干燥，和25ml的1M磷酸钾缓冲液（pH 6.0）。拌匀。 </li><li>加入1 ml 1M的IPTG和500μl的氨苄青霉素（100 mg / ml的无菌水）。 </li><li>摇匀瓶内的溶液倒入60×15毫米（直径×高度）培养皿用吸管援助和25ml血清移液管下面的无菌程序。用12ml琼脂填满每块板。板可被储存在4℃下长达1个月。 </li></ol>必需的自噬基因BEC-1作为一个例子，研究宿主基因在抵御沙门氏菌感染的功能。实验步骤示于图1和表1。协议制备的RNAi治疗的动物进行感染如下，括号中给出各实验步骤的日子。 <ol><li>接种BEC-1 RNAi的喂养和放置-80℃冷冻的细菌片状变成补充100毫克/毫升氨苄青霉素（ 第1天 ）2毫升LB培养基介质控制空载体L4440的RNAi喂养细菌。在整个实验过程中重复此步骤，每周一次有新鲜的RNAi细菌。保存文化在4℃的冰箱时，不使用。 </li><li>种子上的RNAi板百毫升过夜RNAi的细菌培养。准备三BEC-1 RNA干扰和三个控制空v埃克特的RNAi板。培养板在37℃培养过夜（ 第2天 ）。 </li><li>从37℃培养箱中取出的RNAi板，让他们冷却至室温，在板凳上。拿起吃得饱L4野生型N2雌雄同体和他们转移到BEC-1 RNA干扰和控制空载体的RNAi板。将每盘三虫，一式三份板。在同一天，如在步骤3.2（3日 ）中所述制备的RNAi板。 </li><li>孵育的RNAi板的蠕虫在20℃培养箱中培养36〜40小时，传输蠕虫在步骤3.3准备新鲜相应的RNAi板。蠕虫被转移后，将培养板在20℃培养箱中培养64小时（4天 ）。 </li></ol> 4，准备为沙门氏菌感染<ol><li>连胜沙门氏菌 -80℃冷冻股票于1 XLD琼脂平板上孵育板在37℃过夜（5天 </st荣&gt;）。 </li><li>选择一个良好的孤立的黑色沙门氏菌的殖民地，振荡培养过夜（ 第6天 ），其接种于2毫升LB培养基，于37℃。 </li><li>种子80毫升沙门氏菌 1 C.过夜培养线虫 60×15毫米（直径x高度）NGM琼脂平板上并在总准备6片。培养板在室温下搅拌6小时。细菌培养应该干的，并形成对板（7天 ）草坪。 </li></ol> 5，传染的RNAi治疗的蠕虫沙门氏菌 <ol><li>转让BEC-1的RNAi治疗和控制空载体的RNAi治疗L4 N2雌雄同体（设立在步骤3中的蠕虫后代） 沙门氏菌板。将每板40蠕虫的3片为每个组。孵育虫板在20℃下48小时（7天 ）。 </li><li>准备一组新鲜的RNAi板如步骤3.1和3.2（7天及说明<stroNG&gt; 8天）。 </li><li> 48小时后感染，转移沙门氏菌感染蠕虫在步骤5.2准备相应的RNAi板和孵化在20℃（9日 ）。 </li></ol> 6，存活分析<ol><li>每日分数蠕虫的生存，并在产蛋时间蠕虫转移到新鲜对应RNAi板。准备一套新的RNAi板之前，每个蠕虫传输如步骤3.1和3.2中所述。触摸蠕虫身体（头部，中部和尾部）轻轻地用一个终端扁平铂丝。蠕虫的得分为死了，如果该蠕虫体内也没有动静观察。 </li><li>分数蠕虫每日或隔日的生存，并每周两次传送蠕虫新鲜对应RNAi板后，蠕虫停止产卵。 </li><li>毕竟虫死，汇集来自一式三份板作为一个数据集的生存数据。每组输入的生存数据到相应的统计软件，如格拉夫派得PRISM生成生存曲线，并进行Kaplan-Meier生存分析。整个实验被重复至少一次，以确认结论。 </li></ol>

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作者宣称，他们有没有竞争的财务权益。

线虫是一种简单的遗传模型有机体，吃细菌的营养源。因此，很容易与肠道病原体替代它的正常细菌的食物来调查C之间的相互作用线虫和所选择的病原体。在此协议被描述为沙门氏菌感染和C结合线虫喂食的RNAi治疗研究宿主基因在抵御沙门氏菌感染的作用。曾患协议公开C.线虫蠕虫致病菌他们的一生20时，包括沙门氏菌 。在本?...

自由生活的土壤线虫是用于研究许多生物学问题的简单和基因听话的模式生物。C.线虫显性存在自我施肥雌雄同体。雄性自发地由X染色体的过程中配子1,2非分离产生。在丰富的食物，C的存在线虫通过四个幼虫到成虫不断发展。温度也影响C。线虫的发展;更快的发展在较高温度下观察。在实验室中，C.线虫是培养在20℃下在琼脂平板上的标准温度与晶种菌大肠杆菌 （菌株OP50）作为食物1,2。 在过去的十年中，C.线虫已经成为一个无脊椎生物，研究宿主-病原体相互作用3-5。在自然界中，C.线虫吃细菌的养分吨源1,2。它的正常细菌实验室食品，OP50，可以很容易地被其他病原体检查C之间的相互作用线虫和任何选定的病原体。在这些条件下，肠道是感染的主要部位。事实上，广泛的细菌病原体已经显示出致死性感染C.线虫 3-5。 对革兰阴性菌沙门氏菌是一种胃肠道病原体引起人类食源性疾病的全球6,7。C.线虫是一种很好的模式主机沙门氏菌为这种细菌复制和呈现持续肠道感染8-10。C。线虫已经被用于识别新的和先前已知的沙门氏菌毒力因子11。有趣的是，C。线虫的免疫系统成功地限制了沙门氏菌复制。据此前报道，Inhib所自噬基因银行足球比赛呈现在C增加沙门氏菌复制线虫 ，导致受感染蠕虫10的过早死亡。巨自噬（本文中被称为自噬）是一个涉及亚细胞膜的重排螯合细胞质和细胞器运送到溶酶体降解12动态过程。自噬作用已有报道，以限制沙门氏菌复制在C线虫和哺乳动物10,13。 该三线虫基因组测序的第一个多细胞真核生物的基因组;它是响应于RNAi的治疗14-16。此外，RNA干扰可以被有效地通过使蠕虫摄取含有靶基因，被称为RNA干扰喂食16,17的双链RNA的细菌给药。已经生成的全基因组RNAi筛选16,18全基因组RNAi的喂养库。在本文中， 沙门氏菌感染亲母育酚结合的RNAi喂养，让测试C。感兴趣的线虫基因的防止沙门氏菌感染的能力。

<table border="0" cellpadding="0" cellspacing="0" width="621">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">LB Broth</td>
			<td style="width:119px;">Fisher</td>
			<td style="width:119px;">BP9723-500</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">XLD agar</td>
			<td>EMD Chemicals</td>
			<td>1.05287.0500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Bacto Agar</td>
			<td>Fisher</td>
			<td>DF0140-01-0</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Peptone</td>
			<td>Fisher</td>
			<td>BP1420-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium Chloride</td>
			<td>Fisher</td>
			<td>S671-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Calcium Chloride</td>
			<td>Fisher</td>
			<td>C69-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Magnesium Sulfate</td>
			<td>Fisher</td>
			<td>M65-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">IPTG</td>
			<td>Gold Biotechnology</td>
			<td>12481C50</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cholesterol</td>
			<td>Sigma</td>
			<td>C8667-25G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ampicillin</td>
			<td>Fisher&#160;</td>
			<td>BP1760-25</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Salmonella typhimurium</td>
			<td>ATCC</td>
			<td>ATCC14028</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Petri Dish 95 x 15mm</td>
			<td>Fisher</td>
			<td>FB0875714G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Petri Dish 60 x 15mm&#160;</td>
			<td>Fisher</td>
			<td>08-757-13A&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Falcon Serological pipet</td>
			<td>Fisher</td>
			<td>13-668-2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Falcon Express Pipet-Aid</td>
			<td>Fisher</td>
			<td>13-675-42</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">MaxQ6000 shaking incubator&#160;</td>
			<td>Thermo Scientific</td>
			<td>SHKE6000-7</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Incubator</td>
			<td>Percival</td>
			<td>I-36DL</td>
			<td></td>
		</tr>
	</tbody>
</table>

a protocol to infect caenorhabditis elegans with salmonella typhimurium

在过去的十年中，C.线虫已经成为一个无脊椎生物，研究宿主和病原体之间的相互作用，包括对革兰阴性菌鼠伤寒沙门氏菌的宿主防御。沙门氏菌建立持续性感染C.肠道线虫和结果在受感染动物的过早死亡。许多免疫机制C.已经确定对线虫对沙门氏菌感染捍卫。吞噬，进化上保守的溶酶体降解途径，已经示出，以限制沙门氏菌复制在C线虫和哺乳动物。这里，一个协议描述来感染C.线虫与鼠伤寒沙门氏菌 ，其中蠕虫暴露在沙门氏菌在有限的时间，类似沙门氏菌感染的人类。 沙门氏菌感染显著缩短C的寿命线虫&lt;/ em&gt;的。使用必需的自噬基因BEC-1作为一个例子，我们结合这种感染的方法与C线虫 RNAi的喂养方法，并表明该协议可以用于检查C的功能线虫的宿主基因在抵御沙门氏菌感染。由于C。线虫全基因组的RNAi文库的情况下，该协议使得它可以全面筛查C。线虫基因，对沙门氏菌等肠道致病菌保护利用全基因组的RNAi文库。

在20°C时，野生型N2蠕虫的寿命中位数为17天（ 图2A和表2）。 沙门氏菌感染显著降低N2蠕虫的寿命中位数天至10.5天（P = 0.0002，log-rank检验）（ 图2A ）。 如果C。线虫基因在抵御沙门氏菌感染中起重要作用，据预测，其抑制将传授易患沙门氏菌感染。事实上，相对于沙门氏菌感染控制的RNAi治疗N2动物的沙...

Watch this Scientific Journal Video about A Protocol to Infect Caenorhabditis elegans with Salmonella typhimurium at JoVE.com

A Protocol to Infect Caenorhabditis elegans with Salmonella typhimurium

线虫已成为研究宿主-病原体相互作用的新遗传模型。在这里，我们描述了一个协议，感染C。线虫与鼠伤寒沙门氏菌加上双链RNA干扰干扰技术研究宿主基因在抵御沙门氏菌感染的作用。

一个协议感染<em&gt;秀丽隐杆线虫</em&gt;与<em&gt;鼠伤寒沙门氏菌</em

In the last decade, C. elegans has emerged as an invertebrate organism to study interactions between hosts and pathogens, including the host defense ...

a-protocol-to-infect-caenorhabditis-elegans-with-salmonella

Research

JoVE Journal

Immunology and Infection

A Protocol to Infect Caenorhabditis elegans with Salmonella typhimurium

11.5K 次观看.  Florida Atlantic University.  线虫已成为研究宿主-病原体相互作用的新遗传模型。在这里，我们描述了一个协议，感染C。线虫与鼠伤寒沙门氏菌加上双链RNA干扰干扰技术研究宿主基因在抵御沙门氏菌感染的作用。 

视频: A Protocol to Infect Caenorhabditis elegans with Salmonella typhimurium

An Allelotyping PCR for Identifying Salmonella enterica serovars Enteritidis, Hadar, Heidelberg, and Typhimurium

Current commercial PCRs tests for identifying Salmonella target genes unique to this genus. However, there are two species, six subspecies, and over 2,500 different Salmonella serovars, and not all are equal in their significance to public health. For example, finding S. enterica subspecies IIIa Arizona on a table egg layer farm is insignificant compared to the isolation of S. enterica subspecies I serovar Enteritidis, the leading cause of salmonellosis linked to the consumption of table eggs. Serovars are identified based on antigenic differences in lipopolysaccharide (LPS)(O antigen) and flagellin (H1 and H2 antigens). These antigenic differences are the outward appearance of the diversity of genes and gene alleles associated with this phenotype.
We have developed an allelotyping, multiplex PCR that keys on genetic differences between four major S. enterica subspecies I serovars found in poultry and associated with significant human disease in the US. The PCR primer pairs were targeted to key genes or sequences unique to a specific Salmonella serovar and designed to produce an amplicon with size specific for that gene or allele. Salmonella serovar is assigned to an isolate based on the combination of PCR test results for specific LPS and flagellin gene alleles. The multiplex PCRs described in this article are specific for the detection of S. enterica subspecies I serovars Enteritidis, Hadar, Heidelberg, and Typhimurium.
Here we demonstrate how to use the multiplex PCRs to identify serovar for a Salmonella isolate.

An Allelotyping PCR for Identifying Salmonella enterica serovars Enteritidis, Hadar, Heidelberg, and Typhimurium

We describe a multiplex PCR for the rapid detection of Salmonella enterica serovars Enteritidis, Hadar, Heidelberg, and Typhimurium. Specific Salmonella serovars can be identified by targeting a multiplex PCR to genes and sequences unique to the O-antigen biosynthesis cluster and flagellin of a given serovar. Serovar is assigned then to a Salmonella isolate based on the appearance of specific, size amplicons (PCR product) corresponding to the target allele.

一个用于标识Allelotyping PCR扩增沙门氏菌肠炎血清型，哈达尔，海德堡和鼠伤寒沙门氏菌

Current commercial PCRs tests for identifying Salmonella target genes unique to this genus.  However, there are two species, six subspecies, and over ...

科研

免疫与感染

High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages

Salmonella species are zoonotic pathogens and leading causes of food borne illnesses in humans and livestock1. Understanding the mechanisms underlying Salmonella-host interactions are&#160;important to elucidate the molecular pathogenesis of Salmonella infection. The Gentamicin protection assay to phenotype Salmonella association, invasion and replication in phagocytic cells was adapted to allow high-throughput screening to define the roles of deletion mutants of Salmonella enterica serotype Typhimurium in host interactions using RAW 264.7 murine macrophages. Under this protocol, the variance in measurements is significantly reduced compared to the standard protocol, because wild-type and multiple mutant strains can be tested in the same culture dish and at the same time. The use of multichannel pipettes increases the throughput and enhances precision. Furthermore, concerns related to using less host cells per well in 96-well culture dish were addressed. Here, the protocol of the modified in vitro Salmonella invasion assay using phagocytic cells was successfully employed to phenotype 38 individual Salmonella deletion mutants for association, invasion and intracellular replication. The in vitro phenotypes are presented, some of which were subsequently confirmed to have in vivo phenotypes in an animal model. Thus, the modified, standardized assay to phenotype Salmonella association, invasion and replication in macrophages with high-throughput capacity could be utilized more broadly to study bacterial-host interactions.

High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages

A high-throughput assay to in vitro phenotype Salmonella or other bacterial association, invasion, and replication in phagocytic cells with high-throughput capacity was developed. The method was employed to evaluate Salmonella gene knockout mutant strains for their involvements in host-pathogen interactions.

高通量检测到的表型<em&gt;沙门氏菌</em&gt;伤寒协会，侵袭和复制的巨噬细胞

Salmonella species are zoonotic pathogens and leading causes of food borne illnesses in humans and livestock1. Understanding the mechanisms underlying ...

Isolation of Salmonella typhimurium-containing Phagosomes from Macrophages

Salmonella typhimurium is a facultative intracellular bacterium that causes gastroenteritis in humans. After invasion of the lamina propria, S. typhimurium bacteria are quickly detected and phagocytized by macrophages, and contained in vesicles known as phagosomes in order to be degraded. Isolation of S. typhimurium-containing phagosomes have been widely used to study how S. typhimurium infection alters the process of phagosome maturation to prevent bacterial degradation. Classically, the isolation of bacteria-containing phagosomes has been performed by sucrose gradient centrifugation. However, this process is time-consuming, and requires specialized equipment and a certain degree of dexterity. Described here is a simple and quick method for the isolation of S. typhimurium-containing phagosomes from macrophages by coating the bacteria with biotin-streptavidin-conjugated magnetic beads. Phagosomes obtained by this method can be suspended in any buffer of choice, allowing the utilization of isolated phagosomes for a broad range of assays, such as protein, metabolite, and lipid analysis. In summary, this method for the isolation of S. typhimurium-containing phagosomes is specific, efficient, rapid, requires minimum equipment, and is more versatile than the classical method of isolation by sucrose gradient-ultracentrifugation.

Isolation of Salmonella typhimurium-containing Phagosomes from Macrophages

We describe here a simple and quick method for the isolation of Salmonella typhimurium-containing phagosomes from macrophages by coating the bacteria with biotin and streptavidin.

巨噬细胞中含有吞噬的鼠伤寒沙门氏菌的分离

Salmonella typhimurium is a facultative intracellular bacterium that causes gastroenteritis in humans. After invasion of the lamina propria, S. ...

A Facile Protocol to Generate Site-Specifically Acetylated Proteins in Escherichia Coli

Post-translational modifications that occur at specific positions of proteins have been shown to play important roles in a variety of cellular processes. Among them, reversible lysine acetylation is one of the most widely distributed in all domains of life. Although numerous mass spectrometry-based acetylome studies have been performed, further characterization of these putative acetylation targets has been limited. One possible reason is that it is difficult to generate purely acetylated proteins at desired positions by most classic biochemical approaches. To overcome this challenge, the genetic code expansion technique has been applied to use the pair of an engineered pyrrolysyl-tRNA synthetase variant, and its cognate tRNA from Methanosarcinaceae species, to direct the cotranslational incorporation of acetyllysine at the specific site in the protein of interest. After first application in the study of histone acetylation, this approach has facilitated acetylation studies on a variety of proteins. In this work, we demonstrated a facile protocol to produce site-specifically acetylated proteins by using the model bacterium Escherichia coli as the host. Malate dehydrogenase was used as a demonstration example in this work.

A Facile Protocol to Generate Site-Specifically Acetylated Proteins in Escherichia Coli

Genetic code expansion serves as a powerful tool to study a wide range of biological processes, including protein acetylation. Here we demonstrate a facile protocol to exploit this technique for generating homogeneously acetylated proteins at specific sites in Escherichia coli cells.

在大肠杆菌中生成特异的乙酰蛋白的简易协议

Post-translational modifications that occur at specific positions of proteins have been shown to play important roles in a variety of cellular processes. ...

A High-throughput Platform for the Screening of Salmonella spp./Shigella spp.

Fecal-oral transmission of acute gastroenteritis occurs from time to time, especially when people who handled food and water are infected by Salmonella spp./Shigella spp. The gold standard method for the detection of Salmonella spp./Shigella spp. is direct culture but this is labor-intensive and time-consuming. Here, we describe a high-throughput platform for Salmonella spp./Shigella spp. screening, using real-time polymerase chain reaction (PCR) combined with guided culture. There are two major stages: real-time PCR and the guided culture. For the first stage (real-time PCR), we explain each step of the method: sample collection, pre-enrichment, DNA extraction and real-time PCR. If the real-time PCR result is positive, then the second stage (guided culture) is performed: selective culture, biochemical identification and serological characterization. We also illustrate representative results generated from it. The protocol described here would be a valuable platform for the rapid, specific, sensitive and high-throughput screening of Salmonella spp./Shigella spp.

A High-throughput Platform for the Screening of Salmonella spp./Shigella spp.

Salmonella spp./Shigella spp. are common pathogens attributed to diarrhea. Here, we describe a high-throughput platform for the screening of Salmonella spp./Shigella spp. using real-time PCR combined with guided culture.

沙门氏菌筛选的高通量平台.

Fecal-oral transmission of acute gastroenteritis occurs from time to time, especially when people who handled food and water are infected by Salmonella ...

Evaluating Virulence and Pathogenesis of Aeromonas Infection in a Caenorhabditis elegans Model

The human pathogen Aeromonas has been clinically shown to cause gastroenteritis, wound infections, septicemia, and urinary tract infections. Most human diseases have been reported to be associated with four species of bacteria: Aeromonas dhakensis, Aeromonas hydrophila, Aeromonas veronii, and Aeromonas caviae. The model organism Caenorhabditis elegans is a bacterivore that provides an excellent infection model by which to study the bacterial pathogenesis of Aeromonas. Here, we introduce three different experiments to study Aeromonas infection using a C. elegans model, including survival, liquid toxicity, and muscle necrosis assays. The results of the three methods determining the virulence of Aeromonas were consistent. A. dhakensis was shown to be the most toxic among the 4 major Aeromonas species causing clinical infections. These methods are shown to be a convenient way to evaluate the toxicity among and within Aeromonas species and contribute to our understanding of the pathogenesis of Aeromonas infection.

Evaluating Virulence and Pathogenesis of Aeromonas Infection in a Caenorhabditis elegans Model

Here, we introduce three different experiments to study Aeromonas infection in C. elegans. Using these convenient methods, it is easy to evaluate the toxicity among and within Aeromonas species.

线虫模型中气单胞菌感染的毒力及发病机制评价

The human pathogen Aeromonas has been clinically shown to cause gastroenteritis, wound infections, septicemia, and urinary tract infections. Most human ...

Application of Consistent Massage-Like Perturbations on Mouse Calves and Monitoring the Resulting Intramuscular Pressure Changes

Massage is generally recognized to be beneficial for relieving pain and inflammation. Although previous studies have reported anti-inflammatory effects of massage on skeletal muscles, the molecular mechanisms behind are poorly understood. We have recently developed a simple device to apply local cyclical compression (LCC), which can generate intramuscular pressure waves with varying amplitudes. Using this device, we have demonstrated that LCC modulates inflammatory responses of macrophages in situ and alleviates immobilization-induced muscle atrophy. Here, we describe protocols for the optimization and application of LCC as a massage-like intervention against immobilization-induced inflammation and atrophy of skeletal muscles of mouse hindlimbs. The protocol that we have developed can be useful for investigating the mechanism underlying beneficial effects of physical exercise and massage. Our experimental system provides a prototype of the analytical approach to elucidate the mechanical regulation of muscle homeostasis, although further development needs to be made for more comprehensive studies.

Here we describe the protocols for applying defined mechanical loads to mouse calves and for monitoring the concomitant intramuscular pressure changes. The experimental systems that we have developed can be useful for investigating the mechanism behind the beneficial effects of physical exercise and massage.

在小鼠小腿上应用一致的按摩样扰动，并监测由此产生的肌肉压力变化

Massage is generally recognized to be beneficial for relieving pain and inflammation. Although previous studies have reported anti-inflammatory effects of ...

Using Human Induced Pluripotent Stem Cell-derived Intestinal Organoids to Study and Modify Epithelial Cell Protection Against Salmonella and Other Pathogens

The intestinal &#8216;organoid&#8217; (iHO) system, wherein 3-D structures representative of the epithelial lining of the human gut can be produced from human induced pluripotent stem cells (hiPSCs) and maintained in culture, provides an exciting opportunity to facilitate the modeling of the epithelial response to enteric infections. In vivo, intestinal epithelial cells (IECs) play a key role in regulating intestinal homeostasis and may directly inhibit pathogens, although the mechanisms by which this occurs are not fully elucidated. The cytokine interleukin-22 (IL-22) has been shown to play a role in the maintenance and defense of the gut epithelial barrier, including inducing a release of antimicrobial peptides and chemokines in response to infection.
We describe the differentiation of healthy control hiPSCs into iHOs via the addition of specific cytokine combinations to their culture medium before embedding them into a basement membrane matrix-based prointestinal culture system. Once embedded, the iHOs are grown in media supplemented with Noggin, R-spondin-1, epidermal growth factor (EGF), CHIR99021, prostaglandin E2, and Y-27632 dihydrochloride monohydrate. Weekly passages by manual disruption of the iHO ultrastructure lead to the formation of budded iHOs, with some exhibiting a crypt/villus structure. All iHOs demonstrate a differentiated epithelium consisting of goblet cells, enteroendocrine cells, Paneth cells, and polarized enterocytes, which can be confirmed via immunostaining for specific markers of each cell subset, transmission electron microscopy (TEM), and quantitative PCR (qPCR). To model infection, Salmonella enterica serovar Typhimurium SL1344 are microinjected into the lumen of the iHOs and incubated for 90 min at 37 &#176;C, and a modified gentamicin protection assay is performed to identify the levels of intracellular bacterial invasion. Some iHOs are also pretreated with recombinant human IL-22 (rhIL-22) prior to infection to establish whether this cytokine is protective against Salmonella infection.

Using Human Induced Pluripotent Stem Cell-derived Intestinal Organoids to Study and Modify Epithelial Cell Protection Against Salmonella and Other Pathogens

Human induced pluripotent stem cell (hiPSC)-derived intestinal organoids offer exciting opportunities to model enteric diseases in vitro. We demonstrate the differentiation of hiPSCs into intestinal organoids (iHOs), the stimulation of these iHOs with cytokines, and the microinjection of Salmonella Typhimurium into the iHO lumen, enabling the study of an epithelial invasion by this pathogen.

利用人类诱导的多能干细胞衍生的肠道有机体研究和改性上皮细胞对沙门氏菌和其他病原体的保护

The intestinal &#8216;organoid&#8217; (iHO) system, wherein 3-D structures representative of the epithelial lining of the human gut can be produced from ...

Chronic Salmonella Infection Induced Intestinal Fibrosis

Tissue fibrosis characterized by the pathological accumulation of extracellular matrix such as collagen is the outcome of persistent inflammation and dysregulated repair. In inflammatory bowel disease (IBD), fibrosis leads to recurrent stricture formations for which there is no effective therapy other than surgical resection. Due to its late onset, the processes that drive fibrosis is less studied and largely unknown. Therefore, fibrotic complications represent a major challenge in IBD. In this protocol, a robust in vivo model of intestinal fibrosis is described where streptomycin pre-treatment of C57Bl/6 mice followed by oral gavage with vaccine grade Salmonella Typhimurium &#916;AroA mutant leads to persistent pathogen colonization and fibrosis of the cecum. Methodologies for preparing S. Typhimurium &#916;AroA for inoculation, quantifying pathogen loads in the cecum and spleen, and evaluating collagen deposition in intestinal tissues are explained. This experimental disease model is useful for examining host factors that either enhance or exacerbate CD-like intestinal fibrosis.

This protocol describes a mouse model of Salmonella driven intestinal fibrosis that resembles key pathological hallmarks of Crohn&#8217;s disease including transmural inflammation and fibrosis. This method can be used to evaluate host factors that alter fibrotic outcomes using mutant mice maintained on a C57Bl/6 genetic background.

慢性沙门氏菌感染诱发肠纤维化

Tissue fibrosis characterized by the pathological accumulation of extracellular matrix such as collagen is the outcome of persistent inflammation and ...

NF-&#954;B-dependent Luciferase Activation and Quantification of Gene Expression in Salmonella Infected Tissue Culture Cells

The dimeric transcription factor NF-&#954;B regulates many cellular response pathways, including inflammatory pathways by inducing the expression of various cytokines and chemokines. NF-&#954;B is constitutively expressed and is sequestered in the cytosol by the inhibitory protein nuclear factor of kappa light polypeptide gene enhancer in B cells inhibitor, alpha (I&#954;B&#945;). Activation of NF-&#954;B requires the degradation of I&#954;B&#945;, which then exposes a nuclear localization signal on NF-&#954;B and promotes its trafficking to the nucleus. Once in the nucleus, NF-&#954;B binds to the promotor region of NF-&#954;B target genes such as interleukin 6 (IL-6) and IL-23, to promote their expression.
The activation of NF-&#954;B occurs independently of transcription or translation. Therefore, the activation state of NF-&#954;B must be measured either by quantifying NF-&#954;B specifically in the nucleus, or by quantifying expression of NF-&#954;B target genes. In this protocol, cells stably transfected with an NF-&#954;B::luciferase reporter construct are assayed for NF-&#954;B activation using in vitro tissue culture techniques. These cells are infected with Salmonella Typhimurium to activate NF-&#954;B, which traffics to the nucleus and binds to &#954;B sites in the promoter region of luciferase, inducing its expression. Cells are lysed and analyzed with the luciferase assay system. The amount of luciferase produced by the cells correlates with the intensity of the luminescence signal, which is detected by a plate reader. The luminescence signal generated by this procedure provides a quick and highly sensitive method by which to assess NF-&#954;B activation under a range of conditions. This protocol also utilizes quantitative reverse transcription PCR (RT-qPCR) to detect relative mRNA levels that are indicative of gene expression.

NF-&amp;#954;B-dependent Luciferase Activation and Quantification of Gene Expression in &lt;em&gt;Salmonella&lt;/em&gt; Infected Tissue Culture Cells

Here, we present a protocol to quickly and easily measure nuclear factor kappa-light-chain-enhancer of activated B cells (NF-&#954;B) activation in cell lines expressing NF-&#954;B::luciferase reporter constructs, via measurements of luminescence in the cell lysate. Additionally, gene expression is determined via RT-qPCR isolated from cells infected with Salmonella Typhimurium.

在沙门氏菌感染组织培养细胞中，NF-βB依赖性路西酶的激活和基因表达的定量

The dimeric transcription factor NF-&#954;B regulates many cellular response pathways, including inflammatory pathways by inducing the expression of ...