This project was supported by Midwestern University, IL Office of Research and Sponsored Programs (ORSP) and Midwestern University College of Dental Medicine-Illinois (CDMI).

1，HSV毒株和处理注:重组非扩频HSV-1（KOS）gL86和HSV-2（KOS）333gJ -与所使用的五Twiari 36,37分别提供β-半乳糖苷报告基因活性。 <ol><li>从单一的很多并储存在-80℃，使用的病毒以1:Dulbecco改良的Eagle培养基（DMEM），用20％胎牛血清（FBS）的比例为1和脱脂牛奶直到使用。病毒大量的存储之前，由邻 -硝基苯基β-D-吡喃半乳糖苷（ONPG）和5-溴-4-氯-3-吲哚基β-D-吡喃半乳糖苷（X-GAL）测定确定病毒浓度。 </li><li>确定通过X- gal染色病毒活力和感染复数（MOI）的多重性，使用报告病毒条目测定每个实验测定来说，如先前所描述（ 图1）14。 </li><li>稀释病毒（选件-MEM）到所需的MOI。修复单层（多聚甲醛0.5毫升/）染色前。放置病毒活力控制在一个单独的田鼠之三板与多种微生物检测板平行。 </li></ol> 2.海拉细胞299处理<ol><li>在37℃，5％CO 2在DMEM生长用4.5克/升葡萄糖，10％热灭活的胎牛血清（FBS），庆大霉素（50微克/ ml）和L-谷氨酰胺。传代细胞在含有胰蛋白酶溶液80％汇合（乙二胺四乙酸，0.53摩尔EDTA; 0.05％胰蛋白酶5毫升/瓶）。 </li></ol> 3. C.白色念珠菌处理注:C.从临床实验室来源获得白色念珠菌被储存在-80℃下在Remmel脱脂奶2倍介质。 <ol><li>培养冷冻库存到沙氏葡萄糖培养基（37℃）。 24小时后亚文化的C.白色念珠菌到Fungisel介质（37℃; 48小时），进行使用。 </li><li>产生芽管（GT）的形式（挑代表殖民地;3毫升FBS; 3小时; 37℃，绝对600，0.3）。孵育后，洗GT（HBSS; 2倍; 4000 XG）。洗GT加入回暖HBSS（37＃176;℃; 0.32绝对600）。 GT形式应是由血球计数来确定观察到的细胞的99％。 </li><li>通过选取有代表性Fungisel殖民地使酵母形式（YF）股票悬浮液（HBSS 3毫升，0.32绝对600）。算的YF形成数/ ml的显微镜使用血细胞计数器。 YF形式应是由血球计数来确定观察到的细胞的99％。 </li><li>让工作真菌的股票（250微升GT或YF股票在25毫升HBSS; 37℃; 10 5 CFU /毫升） </li></ol> 4. S.金黄色葡萄球菌处理<ol><li>商店S.金黄色葡萄球菌 ATCC 25923（-80℃; Remmel脱脂牛奶2倍）。文化上羊血琼脂（5％; 37℃; 24小时）。挑选有代表性的殖民地和转移到2天内中等甘露醇盐的股票（37℃; 18小时）。 </li><li>让S.金黄色葡萄球菌股票停牌（3毫升HBSS; 1.32阿布斯600 10 8 CFU /毫升） <ol><li>让工作S.金黄色葡萄球菌的股票（100微升在25毫升HBSS股票; 10 5 CFU / ml）中。 </li></ol></li></ol> 5. 念珠菌和S.金黄色葡萄球菌悬浮液<ol><li>使混合C.白色念珠菌和S.金黄色葡萄球菌悬液（250微升YF或GT的股票和25毫升HBSS 100微升金黄色葡萄球菌股票）。 </li></ol> 6.多种微生物生物膜分析<ol><li>种子的96孔板用200μl的2×10 5个 HeLa细胞/毫升（85％汇合的水平）。岩石板（30 - 45分钟; 37℃）温育前（37℃; 5％CO 2培养箱18小时）。洗涤单层（1X;选件-MEM），然后用HSV种子（HSV-1（KOS）gL86或HSV-2（KOS）33 GJ - 100微升选项-MEM; MOI 50和10）。孵育板（3小时; 37℃; 5％CO 2）。使用每天只有一个病毒株。 </li><li>洗感染单层（1×磷酸盐缓冲盐水（PBS）配的Mg +2和Ca +2; 100微升）。用温HBSS更换PBS留下25＆＃181;升的每个孔中。 <ol><li>添加YF，GT和/或S.金黄色葡萄球菌的工作悬浮液（100微升;靶细胞比= 5:1; N = 16）。如表1所示孵育板（静电; 30分钟; 37℃; 5％CO 2）。 </li></ol></li><li>温育后，在时间抽吸一列立即用300μl的PBS再填充用Mg +2和Ca +2。重复此步骤两次，然后添加无线免疫沉淀裂解液（RIPA;过滤消毒; 200微升1:50稀释）。 </li><li>迅速磨碎的HeLa细胞裂解物再放置50微升到甘露醇盐（MS）和/或Fungisel（F）的培养基（ 图2）。传播用玻璃棒弯曲溶解物以90°角。孵育所述板（在37℃下18小时）。手动计数每个平板菌落数。控制包括S的金黄色葡萄球菌和/或C.白色念珠菌坚持HSV未感染的HeLa细胞。 </li></ol> 7.影像学研究&lt;/ P&gt; <ol><li>洗每轮玻璃盖玻片（12毫米; 50ml丙酮在100毫升烧杯）。干燥和消毒盖玻片（的Kimwipes;玻璃培养皿）。放置干燥无菌盖玻片与醇火焰灭菌钳无菌24孔板的孔中。 </li><li> HeLa细胞（1毫升，用于96孔板5倍体积）加入含有洗过的无菌圆形玻璃盖玻片24孔板的孔中。根据在5倍用于96孔板的体积模板（表2）中添加的病毒，细菌和真菌，如在步骤6.2.1上述6.4中所述然后孵育和过程。 </li><li>最后一次洗涤后，通过将大量用甲醇滑动并使其蒸发定为显微镜的细胞。存储在RT板直至染色。 </li><li>对于亮视野显微镜（1000倍最终原放大）填充包含用去离子水甲醇固定盖玻片的井。立即吸水。盖上克结晶紫每个盖玻片。洗盖玻片免费的非绑定染色（去离子水）的。 原位干盖玻片，然后用硬组安装平台到一个标记滑动（图3）附着它们。 </li><li>对于荧光显微镜（100倍的目标;最后1000倍放大倍率原创）按步骤7.4中所述洗盖玻片免费甲醇基本上。干孔中的盖玻片。 <ol><li>干燥后，取出盖玻片，并把它们标记为幻灯片。然后加入1:20稀释的异硫氰酸荧光素（FITC）共轭型单纯疱疹病毒的足够量的1 + 2的gD抗体以覆盖盖玻片（1 - 5微升）。 </li><li>孵育在湿气室中的载玻片在37℃下30分钟。温育后，洗涤盖玻片在PBS中4变化。 </li><li>最后一次洗涤后，返回盖玻片标记的幻灯片。用4&#39;，6-二脒基-2-苯基（;湿气室; 37℃30分钟的DAPI）染色。孵育后洗盖玻片4瓒PBS的水电站，再贴上与硬组的安装介质中的标记幻灯片。 </li><li>允许安装介质以固化在室温在黑暗中24小时。检查既上一个明亮的视野显微镜或FITC和DAPI截止滤光片荧光显微镜下油浸物镜的盖玻片。检查至少50场（每生物体至少100个细胞）为共定位（ 图4）的照片。 </li></ol></li></ol>

The authors have nothing to disclose.

目前暂无信息可到跨越多个域分类， 即原核，真核和病毒宿主微生物的半常任理事国，常任之间复杂的相互作用。因此，我们开发了一种新的体外模型系统来研究由S.生物膜启动金黄色葡萄球菌和C.白色念珠菌对HSV-1和HSV-2感染的HeLa 229（HeLa细胞）细胞38。 HeLa细胞模型系统呈现出独特的优势。这是由于它们缺乏表面纤连蛋白表达的，作为两个S的受体...

<html>人类微生物包括来自身体共享地理区域的多个分类王国不同的生物体。附着到细胞表面是在生物膜的形成，这是微生物定植过程的一部分重要的第一步。包括在微生物可以是引起慢性和持续感染病毒。慢性细胞感染这些病毒可以在推定受体可用性引起的改变。1,2-此外，通过细胞内病原体进入细胞也可能影响宿主细胞膜的流动性/疏水性这反过来又可以改变其他微生物部件的附着，包括细菌和真菌。为了理解可在这些多种病原体在人类宿主的同一地理区域该共定位之间发生的相互作用，我们必须能够学习的表示存在于粘膜表面生物分类王国的频谱病原体的相互作用。 t"的&gt;的疱疹病毒是存在于人类的微生物的永久成员100％的微生物的一个家族3,4-。此外，它们也可以持续在症状的存在和缺乏棚两者。具体地说，单纯疱疹病毒-1和单纯疱疹病毒-2（HSV-1和HSV-2，分别）是在oronasopharynx和生殖道的微生物的永久成员。在免疫能力的个体，无论是HSV-1和HSV-2引起龈，以及生殖器疱疹5-8。在这些站点，单纯疱疹病毒引起潜伏感染为特征的慢性持续性无症状病毒脱落的HSV 9。加入到在改变细胞的结果在nectins，硫酸乙酰肝素，脂筏和疱疹病毒条目介体的表面表达/肿瘤坏死因子受体（HVEM / TNFR）10-25。这些潜在代表共享受体某些细菌和真菌， 如金黄色葡萄球菌和白色念珠菌，这同时致病菌，也可以驻留作为oronasopharynx 26,27的粘膜微生物的成员。内oronasopharynx S.金黄色葡萄球菌和C.白色念珠菌定植占据两个不同的地点。与天然齿的主机，口腔粘膜用HSV-1和C共享白色念珠菌，而前鼻鼻孔都是由S.占用金黄色葡萄球菌 28。然而，尽管体外研究结果，即S。金黄色葡萄球菌坚持口上皮细胞，29,30 S.当正常组织存在金黄色葡萄球菌 29,30不经常口腔标本中分离。鲜为人知的是关于超越的临床研究结果，即生殖道共定植龛称为S.金黄色葡萄球菌与有氧阴道炎，其特点是生殖器炎症，分泌物和性交痛，而C.白色念珠菌产生粘膜病变类似于在口腔中31-35观察。因此，虽然口腔和生殖器microbi的这些部件青梅交叉分类王国小关于它们的相互作用是已知的，因为它影响其通过加入引发生物膜形成与宿主细胞表面5的能力。该协议得到了有效的应用，以确定共同定植/感染的功能性后果。

<table border="0" cellpadding="0" cellspacing="0" width="1185">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">C.albicans</td>
			<td style="width:195px;"></td>
			<td style="width:119px;"></td>
			<td style="width:481px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">BBL Sabouraud Dextrose</td>
			<td style="width:195px;">BD</td>
			<td style="width:119px;">211584</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Fungisel Agar</td>
			<td style="width:195px;">Dot Scientific</td>
			<td style="width:119px;">7205A</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">S.aureus</td>
			<td style="width:195px;"></td>
			<td style="width:119px;"></td>
			<td style="width:481px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Mannitol Salt Agar</td>
			<td style="width:195px;">Troy Biologicals</td>
			<td style="width:119px;">7143B</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Sheep blood agar</td>
			<td style="width:195px;">Troy Biologicals</td>
			<td style="width:119px;">221239</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Hela cells</td>
			<td style="width:195px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:391px;">1xDMEM (Dubelcco&#39;s Modified Eagle Medium, with 4.5 g/L glucose and L-glutamine, without sodium pyruvate</td>
			<td style="width:195px;">Corning</td>
			<td style="width:119px;">10-017-CM</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Gentamicin 50mg/ml</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">1397</td>
			<td>50&#181;g/ml final concentration in the complete DMEM</td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;width:391px;">Trypsin EDTA (0.05% Trypsin, 0.53M EDTA)Solution 1X</td>
			<td style="width:195px;">Corning</td>
			<td>25-052-CI</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Fetal Bovine Serum</td>
			<td style="width:195px;">Atlanta Biologicals</td>
			<td style="width:119px;">S11150</td>
			<td>10% final concentration in the complete DMEM</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Other medium and reagents</td>
			<td style="width:195px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">ONPG</td>
			<td style="width:195px;">Thermo Scientific</td>
			<td style="width:119px;">34055</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Ultra-Pure X gal</td>
			<td style="width:195px;">Invitrogen</td>
			<td style="width:119px;">15520-018</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">1x HBSS (Hanks&#39; Balanced Salt Solution)</td>
			<td style="width:195px;">Corning</td>
			<td style="width:119px;">20-021-CV</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">1XPBS</td>
			<td style="width:195px;">Dot Scientific</td>
			<td style="width:119px;">30042-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">RIPA Lysis</td>
			<td style="width:195px;">Life Technologies</td>
			<td style="width:119px;">89901</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Staining</td>
			<td style="width:195px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Methanol</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">A433P-4</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">HSV 1&#38;2, specific for gD</td>
			<td style="width:195px;">ViroStat</td>
			<td style="width:119px;">196</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">DAPI</td>
			<td style="width:195px;">SIGMA</td>
			<td style="width:119px;">D8417-5MG</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Gram Crystal Violet</td>
			<td style="width:195px;">Troy Biologicals</td>
			<td style="width:119px;">212527</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Supplies</td>
			<td style="width:195px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="29">
			<td height="29" style="height:29px;width:391px;">Petri dish 100X15</td>
			<td style="width:195px;">Dot Scientific</td>
			<td style="width:119px;">229693&#160;</td>
			<td></td>
		</tr>
		<tr height="29">
			<td height="29" style="height:29px;width:391px;">Petri dish 150X15</td>
			<td style="width:195px;">Kord Valmark</td>
			<td style="width:119px;">2902</td>
			<td></td>
		</tr>
		<tr height="26">
			<td height="26" style="height:26px;width:391px;">96-Well plates</td>
			<td style="width:195px;">Evergreen Scientific</td>
			<td style="width:119px;">222-8030-01F</td>
			<td></td>
		</tr>
		<tr height="26">
			<td height="26" style="height:26px;width:391px;">24-well plates</td>
			<td style="width:195px;">Evergreen Scientific</td>
			<td style="width:119px;">222-8044-01F</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Culture tubes 100x13</td>
			<td style="width:195px;">Thomas Scientific</td>
			<td style="width:119px;">9187L61</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Cover slip circles, 12mm</td>
			<td style="width:195px;">Deckglaser</td>
			<td style="width:119px;">CB00120RA1</td>
			<td></td>
		</tr>
	</tbody>
</table>

determination of biofilm initiation on virus-infected cells by bacteria and fungi

整个分类王国，包括真菌，细菌，病毒等多种微生物相互作用的研究没有先前关于审查的微生物病毒的成员是如何影响这些病毒感染的宿主细胞随后微生物相互作用。与细菌和真菌病毒的同居主要是存在于口腔和生殖道的粘膜表面上。粘膜细胞，尤其是那些具有持久的慢性或持续性潜病毒感染，可以有一个显著对微生物的成员通过病毒改变数量和表达的受体的影响的类型。变形例在宿主细胞膜结构会导致正常菌群和机会致病菌的后续成员的以引发在生物膜的形成， 即 ，粘附在第一步骤改变的能力。这项研究描述了BIOFIL的启动为HSV的效果定量和视觉检查方法S. m的形成（粘附） 金黄色葡萄球菌和C.白色念珠菌 。

从这份报告中所描述的系统获得数据的稳健性的级别如图2所示AF 38。通过使用这种系统的与病毒感染的细胞和它们彼此的粘附效果葡萄球菌和真菌相互作用的调制可以划定。这些类型的研究需要的相互作用的显微镜检查中，以确定多种微生物相互作用是否在相同的细胞产生的示于图3和4 38。在这项研究中?...

Watch this Scientific Journal Video about Determination of Biofilm Initiation on Virus-infected Cells by Bacteria and Fungi at JoVE.com

Determination of Biofilm Initiation on Virus-infected Cells by Bacteria and Fungi

A method is described herein for the determination of inter-Kingdom association and competition (bacterial and fungal) for adherence to virus-infected HeLa cell monolayers. This protocol can be extended to multiple combinations of prokaryotes, eukaryotes, and viruses.

生物膜启动对病毒感染的细胞测定细菌和真菌

The study of polymicrobial interactions across the taxonomic kingdoms that include fungi, bacteria and virus have not been previously examined with ...

determination-biofilm-initiation-on-virus-infected-cells-bacteria

Research

JoVE Journal

Immunology and Infection

9.6K 次观看.  Midwestern University. A method is described herein for the determination of inter-Kingdom association and competition (bacterial and fungal) for adherence to virus-infected HeLa cell monolayers. This protocol can be extended to multiple combinations of prokaryotes, eukaryotes, and viruses.

视频: Determination of Biofilm Initiation on Virus-infected Cells by Bacteria and Fungi

Pseudomonas aeruginosa and Saccharomyces cerevisiae Biofilm in Flow Cells

Many microbial cells have the ability to form sessile microbial communities defined as biofilms that have altered physiological and pathological properties compared to free living microorganisms. Biofilms in nature are often difficult to investigate and reside under poorly defined conditions1. Using a transparent substratum it is possible to device a system where simple biofilms can be examined in a non-destructive way in real-time: here we demonstrate the assembly and operation of a flow cell model system, for in vitro 3D studies of microbial biofilms generating high reproducibility under well-defined conditions2,3.
The system consists of a flow cell that serves as growth chamber for the biofilm. The flow cell is supplied with nutrients and oxygen from a medium flask via a peristaltic pump and spent medium is collected in a waste container. This construction of the flow system allows a continuous supply of nutrients and administration of e.g. antibiotics with minimal disturbance of the cells grown in the flow chamber. Moreover, the flow conditions within the flow cell allow studies of biofilm exposed to shear stress. A bubble trapping device confines air bubbles from the tubing which otherwise could disrupt the biofilm structure in the flow cell.
The flow cell system is compatible with Confocal Laser Scanning Microscopy (CLSM) and can thereby provide highly detailed 3D information about developing microbial biofilms. Cells in the biofilm can be labeled with fluorescent probes or proteins compatible with CLSM analysis. This enables online visualization and allows investigation of niches in the developing biofilm. Microbial interrelationship, investigation of antimicrobial agents or the expression of specific genes, are of the many experimental setups that can be investigated in the flow cell system.

Pseudomonas aeruginosa and Saccharomyces cerevisiae Biofilm in Flow Cells

Protocol describing the application of a flow cell system for growing and analyzing microbial biofilms for Confocal Laser Scanning Microscopy (CLSM).

铜绿假单胞菌和酿酒酵母流细胞生物膜

Many microbial cells have the ability to form sessile microbial communities defined as biofilms that have altered physiological and pathological ...

科研

免疫与感染

Microtiter Dish Biofilm Formation Assay

Biofilms are communities of microbes attached to surfaces, which can be found in medical, industrial and natural settings. In fact, life in a biofilm probably represents the predominate mode of growth for microbes in most environments. Mature biofilms have a few distinct characteristics. Biofilm microbes are typically surrounded by an extracellular matrix that provides structure and protection to the community. Microbes growing in a biofilm also have a characteristic architecture generally comprised of macrocolonies (containing thousands of cells) surrounded by fluid-filled channels. Biofilm-grown microbes are also notorious for their resistance to a range of antimicrobial agents including clinically relevant antibiotics.
The microtiter dish assay is an important tool for the study of the early stages in biofilm formation, and has been applied primarily for the study of bacterial biofilms, although this assay has also been used to study fungal biofilm formation. Because this assay uses static, batch-growth conditions, it does not allow for the formation of the mature biofilms typically associated with flow cell systems. However, the assay has been effective at identifying many factors required for initiation of biofilm formation (i.e, flagella, pili, adhesins, enzymes involved in cyclic-di-GMP binding and metabolism) and well as genes involved in extracellular polysaccharide production. Furthermore, published work indicates that biofilms grown in microtiter dishes do develop some properties of mature biofilms, such a antibiotic tolerance and resistance to immune system effectors.
This simple microtiter dish assay allows for the formation of a biofilm on the wall and/or bottom of a microtiter dish. The high throughput nature of the assay makes it useful for genetic screens, as well as testing biofilm formation by multiple strains under various growth conditions. Variants of this assay have been used to assess early biofilm formation for a wide variety of microbes, including but not limited to, pseudomonads, Vibrio cholerae, Escherichia coli, staphylocci, enterococci, mycobacteria and fungi.
In the protocol described here, we will focus on the use of this assay to study biofilm formation by the model organism Pseudomonas aeruginosa. In this assay, the extent of biofilm formation is measured using the dye crystal violet (CV). However, a number of other colorimetric and metabolic stains have been reported for the quantification of biofilm formation using the microtiter plate assay. The ease, low cost and flexibility of the microtiter plate assay has made it a critical tool for the study of biofilms.

The assay describes a rapid means to measure early biofilm formation in bacteria and fungi. This method uses a microtiter plate as the substratum for microbial biofilm formation, and the biofilm is visualized using crystal violet strain. The assay provides either a qualitative or quantitative assay for early biofilm formation.

酶标菜生物膜形成实验

Biofilms are communities of microbes attached to surfaces, which can be found in medical, industrial and natural settings.  In fact, life in a biofilm ...

Following Cell-fate in E. coli After Infection by Phage Lambda

The system comprising bacteriophage (phage) lambda and the bacterium E. coli has long served as a paradigm for cell-fate determination1,2. Following the simultaneous infection of the cell by a number of phages, one of two pathways is chosen: lytic (virulent) or lysogenic (dormant)3,4. We recently developed a method for fluorescently labeling individual phages, and were able to examine the post-infection decision in real-time under the microscope, at the level of individual phages and cells5. Here, we describe the full procedure for performing the infection experiments described in our earlier work5. This includes the creation of fluorescent phages, infection of the cells, imaging under the microscope and data analysis. The fluorescent phage is a "hybrid", co-expressing wild- type and YFP-fusion versions of the capsid gpD protein. A crude phage lysate is first obtained by inducing a lysogen of the gpD-EYFP (Enhanced Yellow Fluorescent Protein) phage, harboring a plasmid expressing wild type gpD. A series of purification steps are then performed, followed by DAPI-labeling and imaging under the microscope. This is done in order to verify the uniformity, DNA packaging efficiency, fluorescence signal and structural stability of the phage stock. The initial adsorption of phages to bacteria is performed on ice, then followed by a short incubation at 35&deg;C to trigger viral DNA injection6. The phage/bacteria mixture is then moved to the surface of a thin nutrient agar slab, covered with a coverslip and imaged under an epifluorescence microscope. The post-infection process is followed for 4 hr, at 10 min interval. Multiple stage positions are tracked such that ~100 cell infections can be traced in a single experiment. At each position and time point, images are acquired in the phase-contrast and red and green fluorescent channels. The phase-contrast image is used later for automated cell recognition while the fluorescent channels are used to characterize the infection outcome: production of new fluorescent phages (green) followed by cell lysis, or expression of lysogeny factors (red) followed by resumed cell growth and division. The acquired time-lapse movies are processed using a combination of manual and automated methods. Data analysis results in the identification of infection parameters for each infection event (e.g. number and positions of infecting phages) as well as infection outcome (lysis/lysogeny). Additional parameters can be extracted if desired.

Following Cell-fate in E. coli After Infection by Phage Lambda

This article describes the procedure for preparing a fluorescently-labeled version of bacteriophage lambda, infection of E. coli bacteria, following the infection outcome under the microscope, and analysis of infection results.

在细胞命运<em&gt; E.大肠杆菌</em感染后的噬菌体λ

The system comprising bacteriophage (phage) lambda and the bacterium E. coli has long served as a paradigm for cell-fate determination1,2. Following the ...

Purification and Visualization of Lipopolysaccharide from Gram-negative Bacteria by Hot Aqueous-phenol Extraction

Lipopolysaccharide (LPS) is a major component of Gram-negative bacterial outer membranes. It is a tripartite molecule consisting of lipid A, which is embedded in the outer membrane, a core oligosaccharide and repeating O-antigen units that extend outward from the surface of the cell1, 2. LPS is an immunodominant molecule that is important for the virulence and pathogenesis of many bacterial species, including Pseudomonas aeruginosa, Salmonella species, and Escherichia coli3-5, and differences in LPS O-antigen composition form the basis for serotyping of strains. LPS is involved in attachment to host cells at the initiation of infection and provides protection from complement-mediated killing; strains that lack LPS can be attenuated for virulence6-8. For these reasons, it is important to visualize LPS, particularly from clinical isolates. Visualizing LPS banding patterns and recognition by specific antibodies can be useful tools to identify strain lineages and to characterize various mutants. 
In this report, we describe a hot aqueous-phenol method for the isolation and purification of LPS from Gram-negative bacterial cells. This protocol allows for the extraction of LPS away from nucleic acids and proteins that can interfere with visualization of LPS that occurs with shorter, less intensive extraction methods9. LPS prepared this way can be separated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) and directly stained using carbohydrate/glycoprotein stains or standard silver staining methods. Many anti-sera to LPS contain antibodies that cross-react with outer membrane proteins or other antigenic targets that can hinder reactivity observed following Western immunoblot of SDS-PAGE-separated crude cell lysates. Protease treatment of crude cell lysates alone is not always an effective way of removing this background using this or other visualization methods. Further, extensive protease treatment in an attempt to remove this background can lead to poor quality LPS that is not well resolved by any of the aforementioned methods. For these reasons, we believe that the following protocol, adapted from Westpahl and Jann10, is ideal for LPS extraction.

We describe a modified hot aqueous-phenol extraction method for purifying lipopolysaccharide (LPS) from Gram-negative bacteria. Once extracted, the LPS can be subsequently analyzed by SDS-PAGE and visualized by direct staining or Western immunoblot.

热酚水提取纯化及革兰氏阴性菌脂多糖的可视化

Lipopolysaccharide (LPS)  is a major component of Gram-negative bacterial outer membranes. It is a tripartite molecule consisting of  lipid A, which is ...

Use of Image Cytometry for Quantification of Pathogenic Fungi in Association with Host Cells

Studies of the cellular pathogenesis mechanisms of pathogenic yeasts such as Candida albicans, Histoplasma capsulatum, and Cryptococcus neoformans commonly employ infection of mammalian hosts or host cells (i.e. macrophages) followed by yeast quantification using colony forming unit analysis or flow cytometry. While colony forming unit enumeration has been the most commonly used method in the field, this technique has disadvantages and limitations, including slow growth of some fungal species on solid media and low and/or variable plating efficiencies, which is of particular concern when comparing growth of wild-type and mutant strains. Flow cytometry can provide rapid quantitative information regarding yeast viability, however, adoption of flow cytometric detection for pathogenic yeasts has been limited for a number of practical reasons including its high cost and biosafety considerations. Here, we demonstrate an image-based cytometric methodology using the Cellometer Vision (Nexcelom Bioscience, LLC) for the quantification of viable pathogenic yeasts in co-culture with macrophages. Our studies focus on detection of two human fungal pathogens: Histoplasma capsulatum and Candida albicans. H. capsulatum colonizes alveolar macrophages by replicating within the macrophage phagosome, and here, we quantitatively assess the growth of H. capsulatum yeasts in RAW 264.7 macrophages using acridine orange/propidium iodide staining in combination with image cytometry. Our method faithfully recapitulates growth trends as measured by traditional colony forming unit enumeration, but with significantly increased sensitivity. Additionally, we directly assess infection of live macrophages with a GFP-expressing strain of C. albicans. Our methodology offers a rapid, accurate, and economical means for detection and quantification of important human fungal pathogens in association with host cells.

Here, we demonstrate how image cytometry can be used for quantification of pathogenic fungi in association with host cells in culture. This technique can be used as an alternative to CFU enumeration.

使用的细胞图像分析仪量化致病真菌与宿主细胞协会

Studies of the cellular pathogenesis mechanisms of pathogenic yeasts such as Candida albicans, Histoplasma capsulatum, and Cryptococcus neoformans ...

Application of Fluorescent Nanoparticles to Study Remodeling of the Endo-lysosomal System by Intracellular Bacteria

Fluorescent nanoparticles (NPs) with desirable chemical, optical and mechanical properties are promising tools to label intracellular organelles. Here, we introduce a method using gold-BSA-rhodamine NPs to label the endo-lysosomal system of eukaryotic cells and monitor manipulations of host cellular pathways by the intracellular pathogen Salmonella enterica. The NPs were readily internalized by HeLa cells and localized in late endosomes/lysosomes. Salmonella infection induced rearrangement of the vesicles and accumulation of NPs in Salmonella-induced membrane structures. We deployed the Imaris software package for quantitative analyses of confocal microscopy images. The number of objects and their size distribution in non-infected cells were distinct from the ones in Salmonella-infected cells, indicating extremely remodeling of the endo-lysosomal system by WT Salmonella.

This article describes methods for the synthesis and fluorescent labeling of nanoparticles (NPs). The NPs were applied in pulse-chase experiments to label the endo-lysosomal system of eukaryotic cells. Manipulation of the endo-lysosomal system by activities of the intracellular pathogen Salmonella enterica were followed by live cell imaging and quantified.

通过胞内细菌，研究内溶酶体系统的改造荧光纳米粒子中的应用

Fluorescent nanoparticles (NPs) with desirable chemical, optical and mechanical properties are promising tools to label intracellular organelles. Here, we ...

T Cells Capture Bacteria by Transinfection from Dendritic Cells

Recently, we have shown, contrary to what is described, that CD4+ T cells, the paradigm of adaptive immune cells, capture bacteria from infected dendritic cells (DCs) by a process called transinfection. Here, we describe the analysis of the transinfection process, which occurs during the course of antigen presentation. This process was unveiled by using CD4+ T cells from transgenic OTII mice, which bear a T cell receptor (TCR) specific for a peptide of ovoalbumin (OVAp), which therefore can form stable immune complexes with infected dendritic cells loaded with this specific OVAp. The dynamics of green fluorescent protein (GFP)-expressing bacteria during DC-T cell transmission can be monitored by live-cell imaging and the quantification of bacterial transinfection can be performed by flow cytometry. In addition, transinfection can be quantified by a more sensitive method based in the use of gentamicin, a non-permeable aminoglycoside antibiotic killing extracellular bacteria but not intracellular ones. This classical method has been used previously in microbiology to study the efficiency of bacterial infections. We hereby explain the protocol of the complete process, from the isolation of the primary cells to the quantification of transinfection.

Here a protocol is presented to measure bacterial capture by CD4+ T cells which occurs during antigen presentation via transinfection from pre-infected dendritic cells (DC). We show how to perform the necessary steps: isolation of primary cells, infection of DC, DC/T cell conjugate formation, and measurement of bacterial T cell transfection.

性T细胞Transinfection从树突状细胞捕捉细菌

Recently, we have shown, contrary to what is described, that CD4+ T cells, the paradigm of adaptive immune cells, capture bacteria from infected dendritic ...

Phenotypic and Functional Analysis of Activated Regulatory T Cells Isolated from Chronic Lymphocytic Choriomeningitis Virus-infected Mice

Regulatory T (Treg) cells, which express Foxp3 as a transcription factor, are subsets of CD4+ T cells. Treg cells play crucial roles in immune tolerance and homeostasis maintenance by regulating the immune response. The primary role of Treg cells is to suppress the proliferation of effector T (Teff) cells and the production of cytokines such as IFN-&#947;, TNF-&#945;, and IL-2. It has been demonstrated that Treg cells&#39; ability to inhibit the function of Teff cells is enhanced during persistent pathogen infection and cancer development. To clarify the function of Treg cells under resting or inflamed conditions, a variety of in vitro suppression assays using mouse or human Treg cells have been devised. The main aim of this study is to develop a method to compare the differences in phenotype and suppressive function between resting and activated Treg cells. To isolate activated Treg cells, mice were infected with lymphocytic choriomeningitis virus (LCMV) clone 13 (CL13), a chronic strain of LCMV. Treg cells isolated from the spleen of LCMV CL13-infected mice exhibited both the activated phenotype and enhanced suppressive activity compared with resting Treg cells isolated from na&#239;ve mice. Here, we describe the basic protocol for ex vivo phenotype analysis to distinguish activated Treg cells from resting Treg cells. Furthermore, we describe a protocol for the measurement of the suppressive activity of fully activated Treg cells.

Here, we describe a protocol to analyze the phenotype of regulatory T (Treg) cells isolated from na&#239;ve and chronic lymphocytic choriomeningitis virus-infected mice. In addition, we provide a process to evaluate the suppressive activity of the Treg cells.

表型和慢性淋巴细胞性脉络丛脑膜炎病毒感染小鼠中分离激活调节性T细胞的功能分析

Regulatory T (Treg) cells, which express Foxp3 as a transcription factor, are subsets of CD4+ T cells. Treg cells play crucial roles in immune tolerance ...

Visualizing the Effects of Sputum on Biofilm Development Using a Chambered Coverglass Model

Biofilms consist of groups of bacteria encased in a self-secreted matrix. They play an important role in industrial contamination as well as in the development and persistence of many health related infections. One of the most well described and studied biofilms in human disease occurs in chronic pulmonary infection of cystic fibrosis patients. When studying biofilms in the context of the host, many factors can impact biofilm formation and development. In order to identify how host factors may affect biofilm formation and development, we used a static chambered coverglass method to grow biofilms in the presence of host-derived factors in the form of sputum supernatants. Bacteria are seeded into chambers and exposed to sputum filtrates. Following 48 hr of growth, biofilms are stained with a commercial biofilm viability kit prior to confocal microscopy and analysis. Following image acquisition, biofilm properties can be assessed using different software platforms. This method allows us to visualize key properties of biofilm growth in presence of different substances including antibiotics.

This protocol describes the visualization of biofilm development following exposure to host-factors using a slide chamber model. This model allows for direct visualization of biofilm development as well as analysis of biofilm parameters using computer software programs.

可视化痰生物膜发展影响使用腔室盖玻片型号

Biofilms consist of groups of bacteria encased in a self-secreted matrix. They play an important role in industrial contamination as well as in the ...

Optical Screening of Novel Bacteria-specific Probes on Ex Vivo Human Lung Tissue by Confocal Laser Endomicroscopy

Improving the speed and accuracy of bacterial detection is important for patient stratification and to ensure the appropriate use of antimicrobials. To achieve this goal, the development of diagnostic techniques to recognize bacterial presence in real-time at the point-of-care is required. Optical imaging for direct identification of bacteria within the host is an attractive approach. Several attempts at chemical probe design and validation have been investigated, however none have yet been successfully translated into the clinic. Here we describe a method for ex vivo validation of bacteria-specific probes for identification of bacteria within the distal lung, imaged by fibered confocal fluorescence microscopy (FCFM). Our model used ex vivo human lung tissue and a clinically approved confocal laser endomicroscopy (CLE) platform to screen novel bacteria-specific imaging compounds, closely mimicking imaging conditions expected to be encountered with patients. Therefore, screening compounds by this technique provides confidence of potential clinical tractability.

Optical Screening of Novel Bacteria-specific Probes on Ex Vivo Human Lung Tissue by Confocal Laser Endomicroscopy

This technique describes an efficient screening process for evaluating bacteria-specific optical imaging agents within ex vivo human lung tissue, by fibered confocal fluorescence microscopy for the rapid identification of small molecule chemical probe-candidates with translatable potential.

激光内在人肺组织中的新型细菌特异探针的光学筛选

Improving the speed and accuracy of bacterial detection is important for patient stratification and to ensure the appropriate use of antimicrobials. To ...