我们感谢埃里卡Mileti，优异的技术支持和安东尼奥·SABATINO博士提供氧舱。 资金来源 ：本工作得到补助从欧盟第七框架计划（IBDase ERC：Dendroworld），和基金会Cariplo的MR和支持居里夫人国际培训移动网络（相声，赠款协议编号：21553-2） KT。

1。获取和组织准备<ol><li>组织（健康或粘膜IBD）是在手术过程中获得。一旦切除试样转移到实验室尽快，保持它的Ca + + / Mg的+ +的HBSS缓冲液在4℃或冰面上青/链霉素补充。 </li></ol> *试样的大小取决于可用的组织得到的组织的一部分，它是严格诊断是没有必要的，并且可以相差很大健康IBD主体之间。健康的组织切除患者结肠癌手术。 <ol start="2"><li>轻轻洗净的组织，它的所有肠系膜材料和清洁。分离粘膜层，粘膜下层，同时保持组织中的HBSS缓冲液在陪替氏培养皿（不一定浸入），用无菌剪刀和镊子。触摸粘膜表面尽可能少的钳子。 </li><li>切粘膜条纹至少1 C米，宽尽可能长。使用两个无菌手术刀，好像你切割食物。 </li><li>洗干净黏膜轻轻的在HBSS，并扩展它在培养皿上心尖的一面朝上。 </li></ol> 2。安装组织<ol><li>准备新鲜培养基（tisDMEM）。使用DMEM培养基，谷氨酰胺（2mM），将NaPyr（1毫摩尔），并添加15％FBS的Na（上胎牛血清 - 北美），1％ITS-X和200 ng / ml的EGF在利用时间。 </li><li> FBS娜（约30毫升，使金属电网将完全被海水淹没）和淹没的金属网格与其他填充10厘米的培养皿。保持板打开，并支持其自来水的塑料缸。 </li></ol> *金属网格是铁做的。网丝与0.5毫米的侧面是正方形状。 <ol start="3"><li> 3微升10或20微升吸管手术胶水。仔细应用于塑料筒的边界之一，而它fIRM的镊子。 </li><li>轻轻地放置在气缸上的根尖侧的黏膜，尽可能靠近尽可能的带材的边界之一。 </li><li> ，得到胶化时间，牢固地附着在纸巾上的气缸，制备的中心孔的器官培养板：取850微升，1毫升培养基中的中心和边缘的板的中央以及支持金属网格。 </li><li>切去多余的组织从缸使用两个无菌手术刀像以前的边界。 </li><li>轻轻提起缸连接的组织，并在板中心放置基底侧上的金属网格。 </li></ol> 3。促进<ol><li>使用您所选择的刺激，在你喜欢的浓度。 </li><li>应用适当的卷在塑料圆筒的​​中心，而不会干扰用移液管尖的缸或粘膜表面。确保您所选择的量均匀地覆盖在气缸内表面。在dicated卷： 大型塑料圆筒：200微升 中型塑料圆筒：100微升 小型塑料圆筒：50微升</li><li>孵育3小时，在传统的孵化器。 </li></ol> *如果你想培养更长的时间点，确保您使用体积更小的刺激（10-20微升），并直接将组织100％O 2的气氛中在1个大气压的压力（见3.5） 。 <ol start="4"><li>关闭根尖组织表面与介质的刺激，不要更换新鲜培养基，因为组织没有得到足够的O 2，如果介质对根尖面对厚厚的一层防止气体交换。 覆盖板。 </li><li>将组织在100％O 2的气氛中，在1个大气压的压力。 </li></ol> 4。收获<ol><li>总培养时间（±2.5小时）24小时后，小心地取出气缸日ê组织的帮助下，用手术刀轻轻刮胶和存储取决于所需的分析（修复免疫组化和/或免疫荧光法，或急速冷冻在液氮RNA纯化和基因表达谱或蛋白质纯化和Western blot检测）。 </li><li>收获基底介质，细胞因子分泌剖析。在8,000 rpm下离心7分钟，以沉淀碎片，将上清转移在Eppendorf管（或等分试样），并立即存储于-20℃。 </li></ol> *如果你想以保持更长上清，它们储存在-80°C。

<ol>
	<li>Schuller, S., Lucas, M., Kaper, J. B., Giron, J. A., Phillips, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+ex+vivo+response+of+human+intestinal+mucosa+to+enteropathogenic+Escherichia+coli+infection.">The ex vivo response of human intestinal mucosa to enteropathogenic Escherichia coli infection.</a> Cell. Microbiol. 11, 521-530 (2009).</li><li>Tsilingiri, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probiotic+and+postbiotic+activity+in+health+and+disease:+comparison+on+a+novel+polarised+ex-vivo+organ+culture+model.">Probiotic and postbiotic activity in health and disease: comparison on a novel polarised ex-vivo organ culture model.</a> Gut. , (2012).</li><li>Tsilingiri, K., Rescigno, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Should+probiotics+be+tested+on+ex+vivo+organ+culture+models?.">Should probiotics be tested on ex vivo organ culture models?.</a> Gut Microbes. , (2012).</li><li>Mileti, E., Matteoli, G., Iliev, I. D., Rescigno, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+the+immunomodulatory+properties+of+three+probiotic+strains+of+Lactobacilli+using+complex+culture+systems:+prediction+for+in+vivo+efficacy.">Comparison of the immunomodulatory properties of three probiotic strains of Lactobacilli using complex culture systems: prediction for in vivo efficacy.</a> PLoS One. 4, e7056 (2009).</li><li>Cencic, A., Langerholc, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+cell+models+of+the+gut+and+their+applications+in+food+microbiology--a+review.">Functional cell models of the gut and their applications in food microbiology--a review.</a> Int. J. Food Microbiol. 141, S4-S14 (2010).</li><li>te Velde, A. A., Verstege, M. A., Hommes, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Critical+appraisal+of+the+current+practice+in+murine+TNBS-induced+colitis.">Critical appraisal of the current practice in murine TNBS-induced colitis.</a> Inflamm. Bowel Dis. 12, 995-999 (2006).</li><li>Senior, P. V., Pritchett, C. J., Sunter, J. P., Appleton, D. R., Watson, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crypt+regeneration+in+adult+human+colonic+mucosa+during+prolonged+organ+culture.">Crypt regeneration in adult human colonic mucosa during prolonged organ culture.</a> J. Anat. 134, 459-469 (1982).</li><li>Browning, T. H., Trier, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organ+culture+of+mucosal+biopsies+of+human+small+intestine.">Organ culture of mucosal biopsies of human small intestine.</a> J. Clin. Invest. 48, 1423-1432 (1969).</li><li>Besselink, M. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probiotic+prophylaxis+in+predicted+severe+acute+pancreatitis:+a+randomised,+double-blind,+placebo-controlled+trial.">Probiotic prophylaxis in predicted severe acute pancreatitis: a randomised, double-blind, placebo-controlled trial.</a> Lancet. 371, 651-659 (2008).</li><li>Lakhdari, O., et al. <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+NF-kappaB+modulation+capabilities+within+human+intestinal+commensal+bacteria.">Identification of NF-kappaB modulation capabilities within human intestinal commensal bacteria.</a> J. Biomed. Biotechnol. 2011, 282356 (2011).</li></ol>

没有利益冲突的声明。

需要有关生理模型人体肠道黏膜上的治疗方法，可以有效地测试一直很重视。许多研究人员已经发现在两种细胞和小鼠模型6迄今所使用为该目的而潜在的工件和缺陷。事实上，即使有前途的临床前数据往往是获得，这些很少转化为显着的临床益处。 在这项工作中所描述的方法，提出了一个相对简单的，但有效的，新颖的适应人体肠道粘膜偏振方式的外植体的培养和?...

<table border="1">
	<tbody>
		<tr>
			<td>Regeant</td>
			<td>Company</td>
			<td>Catalog No.</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>Reagents</td>
		</tr>
		<tr>
			<td>10X HBSS</td>
			<td>Eurocalne</td>
			<td>ECM4006XL</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Peni/Strepto</td>
			<td>Lonza</td>
			<td>DE17602E</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Gentamycin</td>
			<td>Gibco</td>
			<td>15750-037</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>Lonza</td>
			<td>BE12614</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>FBS-Na</td>
			<td>Gibco</td>
			<td>16000-044</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>100X ITS-X</td>
			<td>Gibco</td>
			<td>51500-056</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>EGF</td>
			<td>Tebu-bio</td>
			<td>100-15</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>L-Glutamine</td>
			<td>Lonza</td>
			<td>BE17605E</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Non essential aminoacids 100X</td>
			<td>Gibco</td>
			<td>11140-035</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>NaPyr</td>
			<td>Gibco</td>
			<td>11360-039</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>Materials</td>
		</tr>
		<tr>
			<td>Cloning cylinders 6x8 mm</td>
			<td>BellCo</td>
			<td>2090-00608</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Cloning cylinders 8x8 mm</td>
			<td>BellCo</td>
			<td>2090-0080</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Cloning cylinders 10x10 mm</td>
			<td>BellCo</td>
			<td>2090-01010</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Metal grids</td>
			<td>Home made</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Centre well organ culture plate</td>
			<td>BD Falcon</td>
			<td>353037</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Surgical glue (Vetbond)</td>
			<td>3M</td>
			<td>1469SB</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Oxygen Jars</td>
			<td>Home made</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Oxygen tanks</td>
			<td>Air Liquid Sanit&agrave;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
	</tbody>
</table>

a novel method for the culture and polarized stimulation of human intestinal mucosa explants

目前很少有车型存在，逼真地模拟复杂的人类肠道内的微环境，在那里发生的各种相互作用。适当的稳态直接取决于这些相互作​​用的，因为它们形成整个的免疫反应对食物抗原诱导免疫耐受，而在同一时间对意外地与食物摄入的病原微生物的有效的免疫反应。 肠道动态平衡也被保留通过各种微生物（包括食品相关的有益的细菌菌株）和主机，调节附件/降解粘液之间复杂的相互作用，生产抗菌肽上皮屏障，而“教育”上皮细胞表型独特，肠道居民淋巴细胞人口控制的耐受性或免疫原性。这些相互作用到目前为止已经很难复制的体外实验可以使用培养的细胞系或外周血单核细胞。此外，小鼠模型显着不同的元件相对于人体肠道对肠粘膜（粘液层的组织，共生细菌群落）。因此在诊所被带到重要的压力相关的或病理情况下，如肠易激综合征，炎性肠病或结直肠癌的治疗方法有多种，研究一直难以开展。 为了解决这些问题，我们开发了一种新的系统，使我们能够刺激人体肠道黏膜植保留其在原位空调主机菌群和免疫反应，极化方式。偏振光根尖刺激引起的免疫反应的结果，非常重要的。已经一再证明，相同的刺激，可以产生完全不同的反应，当他们绕过心尖面对肠道外延thelium basolaterally或刺激上皮细胞进入固有层组件的直接接触，切换从耐受性表型的免疫原性，并在区域造成不必要的过度的炎症反应。 通过胶粘的分隔的区域的顶端面的粘膜刺激对将要描述在协议中的一个洞穴缸实现极化刺激。我们用这个模型来考察，其中包括三个不同的乳酸杆菌菌株的不同影响。我们发现，这个模型系统评估益生菌的免疫调节特性，在健康和疾病的情况下是非常强大的。

我们成功地保持健康和传染性法氏囊病的人类文化肠粘膜至少24小时保护组织的福祉。根据先前的观察1，这是唯一可能的，如果培养时间（至少85％的总）的大多数发生在O 2，组织没有生存24小时，在传统的孵化器（ 图2）。我们也显示出，取决于上的的刺激（心尖比基底侧）和刺激的免疫原性2,3的极性在此模型上可观察到的外植体的不同的反应。 <p class="jo...

Watch this Scientific Journal Video about A Novel Method for the Culture and Polarized Stimulation of Human Intestinal Mucosa Explants at JoVE.com

A Novel Method for the Culture and Polarized Stimulation of Human Intestinal Mucosa Explants

我们引入了一种新的方法，为维护人类文化和监测至少24小时应对各类刺激肠黏膜。有了我们的方法中，维持组织的极性，可用于生理刺激通过心尖路由。

文化与偏振刺激人体肠道黏膜植的新方法

Few models currently exist to realistically simulate the complex human intestine's micro-environment, where a variety of interactions take place. Proper ...

a-novel-method-for-culture-polarized-stimulation-human-intestinal

Research

JoVE Journal

Biology

13.0K 次观看.  European Institute of Oncology. 我们引入了一种新的方法，为维护人类文化和监测至少24小时应对各类刺激肠黏膜。有了我们的方法中，维持组织的极性，可用于生理刺激通过心尖路由。

视频: A Novel Method for the Culture and Polarized Stimulation of Human Intestinal Mucosa Explants

Method for Culture of Early Chick Embryos ex vivo (New Culture)

The chick embryo is a valuable tool in the study of early embryonic development. Its transparency, accessibility and ease of manipulation, make it an ideal tool for studying  the formation and patterning of brain, neural tube, somite and heart primordia. Applications of chick embryo culture include electroporation of DNA or RNA constructs in order to analyze gene function, grafts of growth factor coated beads such as FGFs and BMPs , as well as whole mount in situ hybridization and immunohistochemistry. This video demonstrates the different steps in chick embryo culture; First, the embryo is explanted in saline. Then, the embryo is centered on a glass ring. The membranes surrounding the embryo are lifted along the walls of the ring. The ring is then placed in a culture dish containing a pool of albumine. The culture dish is sealed and placed in a humid chamber, where the embryo is cultured for up to 24 hrs. Finally, the embryo is removed from the ring, fixed and processed for further applications. A troubleshooting guide is also presented.

Method for Culture of Early Chick Embryos ex vivo New Culture

This video demonstrates New culture, a method by which chick embryos are cultured outside the egg for up to 24 hr. This method enables one to study early development (primitive streak to 14 som.), a period corresponding to E7-9 in mouse. Applications of this technique include electroporation, in situ hybridization and immunohistochemistry.

文化早期鸡胚体外（新文化）的方法

The chick embryo is a valuable tool in the study of early embryonic development. Its transparency, accessibility and ease of manipulation, make it an ...

科研

生物学

Preparation and Culture of Rat Lens Epithelial Explants for Studying Terminal Differentiation

The anterior surface of the ocular lens is covered by a monolayer of epithelial cells, which proliferate in an annular zone underlying the ciliary body.  Following division, these cells migrate posteriorly, where FGF diffusing from the retina induces them to differentiate into a posterior array of elongated lens fiber cells, which compose the bulk of the lens.  Differentiation of lens epithelial cells into lens fibers can be induced in vitro by culturing explants of the central region of the anterior epithelium in the presence of FGF-2.  Explants are prepared from lenses of neonatal rats by removing the lens from the eye and grasping the lens capsule on the posterior side with dissecting tweezers.  The posterior capsule is then gently torn open and pressed down into the plastic bottom of a tissue culture dish. The peripheral regions of the explant are removed with a scalpel and the central area is then cultured in the presence of 100ng/ml FGF-2 for as long as 2-3 weeks, depending on the parameters to be studied.  Since epithelial cells in cultured explants differentiate in approximate synchrony over a period of days to weeks, the time course of signaling and gene expression can be determined using molecular, biochemical, and pharmacological techniques.  Immunofluorescence microscopy is a powerful adjunct to these methods as it demonstrates the subcellular localization of proteins of interest and can reveal the physiological consequences of experimental manipulations of signaling pathways.

Explants of the central region of rat lens epithelia differentiate synchronously when cultured in the presence of FGF-2. Immunofluorescence microscopy of such cultures can provides novel information about gene expression and signaling events associated with terminal differentiation.

大鼠晶状体上皮细胞外植体的制备及文化学习终末分化

The anterior surface of the ocular lens is covered by a monolayer of epithelial cells, which proliferate in an annular zone underlying the ciliary body.  ...

The Method of Rodent Whole Embryo Culture using the Rotator-type Bottle Culture System

Whole embryo culture (WEC) technique has been developed in 1950's by New and his colleagues, and applied for developmental biology 1. Although development and growth of mammalian embryos are critically dependent on the function of the placenta, WEC technique allows us to culture mouse and rat embryos ex vivo condition during limited periods corresponding to midgestation stages during embryonic day (E) 6.5-E12.5 in the mouse or E8.5-E14.5 in the rat 2, 3, 4. In WEC, we can directly target desired areas of embryos using fine glass capillaries because embryos can be manipulated under the microscope. Therefore, rodent WEC is very useful technique when we want to study dynamic developmental processes of postimplanted mammalian embryos. Up to date, several types of WEC systems have been developed 1. Among those, the rotator-type bottle culture system is most popular and suitable for long-term culture of embryos at midgestation, i.e., after E9.5 and E11.5 in the mouse and rat, respectively 1. In this video protocol, we demonstrate our standard procedures of rat WEC after E12.5 using a refined model of the original rotator system, which was designed by New and Cockroft 5, 6, and introduce various applications of WEC technique for studies in mammalian developmental biology.

Whole embryo culture technique allows us to culture mouse and rat embryos ex vivo condition during limited periods corresponding to midgestation stages. In this video protocol, we demonstrate our standard procedures of rat whole embryo culture after E12.5 using the rotator-type bottle culture system.

鼠类全胚胎培养方法，使用的肩型瓶培养系统

Whole embryo culture (WEC) technique has been developed in 1950's by New and his colleagues, and applied for developmental biology 1. Although development ...

Blastomere Explants to Test for Cell Fate Commitment During Embryonic Development

Fate maps, constructed from lineage tracing all of the cells of an embryo, reveal which tissues descend from each cell of the embryo. Although fate maps are very useful for identifying the precursors of an organ and for elucidating the developmental path by which the descendant cells populate that organ in the normal embryo, they do not illustrate the full developmental potential of a precursor cell or identify the mechanisms by which its fate is determined. To test for cell fate commitment, one compares a cell's normal repertoire of descendants in the intact embryo (the fate map) with those expressed after an experimental manipulation. Is the cell's fate fixed (committed) regardless of the surrounding cellular environment, or is it influenced by external factors provided by its neighbors? Using the comprehensive fate maps of the Xenopus embryo, we describe how to identify, isolate and culture single cleavage stage precursors, called blastomeres. This approach allows one to assess whether these early cells are committed to the fate they acquire in their normal environment in the intact embryo, require interactions with their neighboring cells, or can be influenced to express alternate fates if exposed to other types of signals.

The fate of an individual embryonic cell can be influenced by inherited molecules and/or by signals from neighboring cells. Utilizing fate maps of the cleavage stage Xenopus embryo, single blastomeres can be identified for culture in isolation to assess the contributions of inherited molecules versus cell-cell interactions.

卵裂球外植体测试胚胎发育过程中细胞命运的承诺

Fate maps, constructed from lineage tracing all of the cells of an embryo, reveal  which tissues descend from each cell of the embryo.  Although fate maps ...

A Novel Ex vivo Culture Method for the Embryonic Mouse Heart

Developmental studies in the mouse are hampered by the inaccessibility of the embryo during gestation. Thus, protocols to isolate and culture individual organs of interest are essential to provide a method of both visualizing changes in development and allowing novel treatment strategies. To promote the long-term culture of the embryonic heart at late stages of gestation, we developed a protocol in which the excised heart is cultured in a semi-solid, dilute Matrigel. This substrate provides enough support to maintain the three-dimensional structure but is flexible enough to allow continued contraction. In brief, hearts are excised from the embryo and placed in a mixture of cold Matrigel diluted 1:1 with growth medium. After the diluted Matrigel solidifies, growth medium is added to the culture dish. Hearts excised as late as embryonic day 16.5 were viable for four days post-dissection. Analysis of the coronary plexus shows that this method does not disrupt coronary vascular development. Thus, we present a novel method for long-term culture of embryonic hearts.

A Novel Ex vivo Culture Method for the Embryonic Mouse Heart

Developmental studies in the mouse are hampered by the inaccessibility of the embryo during gestation. To promote the long-term culture of the embryonic heart at late stages of gestation, we developed a protocol in which the excised heart is cultured in a semi-solid, dilute Matrigel.

一种新型的<em&gt;体外</em小鼠胚胎心脏的培养方法

Developmental studies in the mouse are hampered  by the inaccessibility of the embryo during gestation. Thus, protocols to  isolate and culture individual ...

The Slice Culture Method for Following Development of Tooth Germs In Explant Culture

Explant culture allows manipulation of developing organs at specific time points&#160;and is therefore an important method for the developmental biologist. For many organs it is difficult to access developing tissue to allow monitoring during ex vivo culture. The slice culture method allows access to tissue so that morphogenetic movements can be followed and specific cell populations can be targeted for manipulation or lineage tracing.
In this paper we describe a method of slice culture that has been very successful for culture of tooth germs in a range of species. The method provides excellent access to the tooth germs, which develop at a similar rate to that observed in vivo, surrounded by the other jaw tissues. This allows tissue interactions between the tooth and surrounding tissue to be monitored. Although this paper concentrates on tooth germs, the same protocol can be applied to follow development of a number of other organs, such as salivary glands, Meckel&#39;s cartilage, nasal glands, tongue, and ear.

Here we detail a method to culture tooth germs in mandible slices using a tissue chopper. This method allows unique access to the tooth during development, providing excellent opportunity for manipulation and lineage tracing, not available using more traditional culture methods.

切片培养法继牙胚在植文化的发展

Explant culture allows manipulation of developing organs at specific time points&#160;and is therefore an important method for the developmental ...

Subcloning Plus Insertion (SPI) - A Novel Recombineering Method for the Rapid Construction of Gene Targeting Vectors

Gene targeting refers to the precise modification of a genetic locus using homologous recombination. The generation of novel cell lines and transgenic mouse models using this method necessitates the construction of a &#8216;targeting&#8217; vector, which contains homologous DNA sequences to the target gene, and has for many years been a limiting step in the process. Vector construction can be performed in vivo in Escherichia coli cells using homologous recombination mediated by phage recombinases using a technique termed recombineering. Recombineering is the preferred technique to subclone the long homology sequences (>4kb) and various targeting elements including selection markers that are required to mediate efficient allelic exchange between a targeting vector and its cognate genomic locus. Typical recombineering protocols follow an iterative scheme of step-wise integration of the targeting elements and require intermediate purification and transformation steps. Here, we present a novel recombineering methodology of vector assembly using a multiplex approach. Plasmid gap repair is performed by the simultaneous capture of genomic sequence from mouse Bacterial Artificial Chromosome libraries and the insertion of dual bacterial and mammalian selection markers. This subcloning plus insertion method is highly efficient and yields a majority of correct recombinants. We present data for the construction of different types of conditional gene knockout, or knock-in, vectors and BAC reporter vectors that have been constructed using this method. SPI vector construction greatly extends the repertoire of the recombineering toolbox and provides a simple, rapid and cost-effective method of constructing these highly complex vectors.

Subcloning Plus Insertion SPI - A Novel Recombineering Method for the Rapid Construction of Gene Targeting Vectors

Gene targeting methodologies can be used to generate transgenic mice with knockout, knock-in and tagged alleles. Here, we describe an improved method of recombineering in E. coli, that we term &#8216;subcloning plus insertion&#8217;, which can be used to generate custom gene targeting vectors rapidly.

亚克隆加插入（SPI） - 一种新型重组工程方法基因打靶载体的快速构建

Gene targeting refers to the precise modification of a genetic locus using homologous recombination. The generation of novel cell lines and transgenic ...

A Protocol for Lentiviral Transduction and Downstream Analysis of Intestinal Organoids

Intestinal crypt-villus structures termed organoids, can be kept in sustained culture three dimensionally when supplemented with the appropriate growth factors. Since organoids are highly similar to the original tissue in terms of homeostatic stem cell differentiation, cell polarity and presence of all terminally differentiated cell types known to the adult intestinal epithelium, they serve as an essential resource in experimental research on the epithelium. The possibility to express transgenes or interfering RNA using lentiviral or retroviral vectors in organoids has increased opportunities for functional analysis of the intestinal epithelium and intestinal stem cells, surpassing traditional mouse transgenics in speed and cost. In the current video protocol we show how to utilize transduction of small intestinal organoids with lentiviral vectors illustrated by use of doxycylin inducible transgenes, or IPTG inducible short hairpin RNA for overexpression or gene knockdown. Furthermore, considering organoid culture yields minute cell counts that may even be reduced by experimental treatment, we explain how to process organoids for downstream analysis aimed at quantitative RT-PCR, RNA-microarray and immunohistochemistry. Techniques that enable transgene expression and gene knock down in intestinal organoids contribute to the research potential that these intestinal epithelial structures hold, establishing organoid culture as a new standard in cell culture.

In this video protocol we give a step by step explanation of lentiviral transduction in organoids of primary intestinal epithelium and of processing and downstream analysis of these cultures by quantitative RT-PCR, RNA-microarray and immunohistochemistry.

协议的慢病毒转导与肠组织体下游分析

Intestinal crypt-villus structures termed organoids, can be kept in sustained culture three dimensionally when supplemented with the appropriate growth ...

A Method for Selecting Structure-switching Aptamers Applied to a Colorimetric Gold Nanoparticle Assay

Small molecules provide rich targets for biosensing applications due to their physiological implications as biomarkers of various aspects of human health and performance. Nucleic acid aptamers have been increasingly applied as recognition elements on biosensor platforms, but selecting aptamers toward small molecule targets requires special design considerations. This work describes modification and critical steps of a method designed to select structure-switching aptamers to small molecule targets. Binding sequences from a DNA library hybridized to complementary DNA capture probes on magnetic beads are separated from nonbinders via a target-induced change in conformation. This method is advantageous because sequences binding the support matrix (beads) will not be further amplified, and it does not require immobilization of the target molecule. However, the melting temperature of the capture probe and library is kept at or slightly above RT, such that sequences that dehybridize based on thermodynamics will also be present in the supernatant solution. This effectively limits the partitioning efficiency (ability to separate target binding sequences from nonbinders), and therefore many selection rounds will be required to remove background sequences. The reported method differs from previous structure-switching aptamer selections due to implementation of negative selection steps, simplified enrichment monitoring, and extension of the length of the capture probe following selection enrichment to provide enhanced stringency. The selected structure-switching aptamers are advantageous in a gold nanoparticle assay platform that reports the presence of a target molecule by the conformational change of the aptamer. The gold nanoparticle assay was applied because it provides a simple, rapid colorimetric readout that is beneficial in a clinical or deployed environment. Design and optimization considerations are presented for the assay as proof-of-principle work in buffer to provide a foundation for further extension of the work toward small molecule biosensing in physiological fluids.

A protocol is provided to select structure-switching aptamers for small molecule targets based on a tunable stringency magnetic bead selection method. Aptamers selected with structure-switching properties are beneficial for assays that require a conformational change to signal the presence of a target, such as the described gold nanoparticle assay.

适用于比色金纳米粒子检测方法的选择结构切换适配方法

Small molecules provide rich targets for biosensing applications due to their physiological implications as biomarkers of various aspects of human health ...

Cryosectioning Method for Microdissection of Murine Colonic Mucosa

The colonic mucosal tissue provides a vital barrier to luminal antigens. This barrier is composed of a monolayer of simple columnar epithelial cells. The colonic epithelium is dynamically turned over and epithelial cells are generated in the stem cell containing crypts of Lieberk&#252;hn. Progenitor cells produced in the crypt-bases migrate toward the luminal surface, undergoing a process of cellular differentiation before being shed into the gut lumen. In order to study these processes at the molecular level, we have developed a simple method for the microdissection of two spatially distinct regions of the colonic mucosa; the proliferative crypt zone, and the differentiated surface epithelial cells. Our objective is to isolate specific crypt and surface epithelial cell populations from mouse colonic mucosa for the isolation of RNA and protein.

Here we describe a simple method for the isolation of spatially distinct murine colonic epithelial surface cells from the underlying crypt-base cells.

Cryosectioning方法小鼠结肠黏膜显微切割

The colonic mucosal tissue provides a vital barrier to luminal antigens. This barrier is composed of a monolayer of simple columnar epithelial cells. The ...