| High-throughput Microscopic Analysis of Salmonella Invasion of Host Cells
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Author:
Date:
2018-09-20
[Abstract] Salmonella is a Gram-negative bacterium causing a gastro-enteric disease called salmonellosis. During the first phase of infection, Salmonella uses its flagella to swim near the surface of the epithelial cells and to target specific site of infection. In order to study the selection criteria that determine which host cells are targeted by the pathogen, and to analyze the relation between infecting Salmonella (i.e., cooperation or competition), we have established a high-throughput microscopic assay of HeLa cells sequentially infected with fluorescent bacteria. Using an automated pipeline of image analysis, we quantitatively characterized a multitude of parameters of infected and non-infected cells. Based on this, we established a predictive model that ...
[摘要] 沙门氏菌是革兰氏阴性细菌，引起称为沙门氏菌病的胃肠疾病。在感染的第一阶段，沙门氏菌使用其鞭毛在上皮细胞表面附近游泳并靶向特定的感染部位。为了研究确定哪种宿主细胞被病原体靶向的选择标准，并分析感染沙门氏菌（ ie ，合作或竞争）之间的关系，我们有建立了对荧光细菌依次感染的HeLa细胞的高通量显微镜检测。使用自动化图像分析管道，我们定量表征了感染和未感染细胞的众多参数。基于此，我们建立了一个预测模型，使我们能够识别宿主细胞易受感染的参数。我们发现宿主细胞易损性有两个来源：病原体诱导的细胞易感性从沙门氏菌摄取中出现并持续存在于感染过程的后期阶段;以及与细胞固有属性相关的宿主细胞固有的脆弱性，例如局部细胞拥挤和胆固醇含量。我们的方法基于形态学或分子宿主细胞参数预测单层上皮细胞中沙门氏菌感染的概率。在这里，我们提供了工作流程的详细描述，包括基于计算机的分析管道。我们的方法有可能应用于研究宿主 - 病原体相互作用的其他组合。
【背景】鼠伤寒沙门氏菌血清型鼠伤寒沙门氏菌通过摄入受污染的食物或水感染宿主，引起沙门氏菌病。一旦细菌到达肠道的远端回肠，它们就会侵入广泛的宿主细胞，包括肠上皮细胞（Watson和Holden，2010）。在宿主细胞入侵的第一阶段，沙门氏菌选择其目标，使用其鞭毛游泳并扫描上皮表面（Misselwitz et ...
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| A Co-culture Assay to Determine Efficacy of TNF-α Suppression by Biomechanically Induced Human Bone Marrow Mesenchymal Stem Cells
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Author:
Date:
2017-08-20
[Abstract] The beneficial effects of mesenchymal stem cell (MSC)-based cellular therapies are believed to be mediated primarily by the ability of MSCs to suppress inflammation associated with chronic or acute injury, infection, autoimmunity, and graft-versus-host disease. To specifically address the effects of frictional force caused by blood flow, or wall shear stress (WSS), on human MSC immunomodulatory function, we have utilized microfluidics to model WSS at the luminal wall of arteries. Anti-inflammatory potency of MSCs was subsequently quantified via measurement of TNF-α production by activated murine splenocytes in co-culture assays. The TNF-α suppression assay serves as a reproducible platform for functional assessment of MSC potency and demonstrates predictive value as a surrogate assay for ...
[摘要] 认为基于间充质干细胞（MSC）的细胞疗法的有益作用主要是由能够抑制慢性或急性损伤，感染，自身免疫和移植物抗宿主病相关炎症的能力介导的。 为了专门解决由血流或壁剪应力（WSS）引起的摩擦力对人MSC免疫调节功能的影响，我们利用微流体在动脉腔壁上建模WSS。 随后通过在共培养测定中通过活化的小鼠脾细胞测量TNF-α产生来量化MSC的抗炎效力。 TNF-α抑制测定作为MSC效力的功能评估的可重现平台，并且表现出作为MSC治疗功效的替代测定的预测价值。
【背景】间充质干细胞（MSC）的免疫调节活性由直接细胞相互作用和旁分泌因子介导（Singer和Caplan，2011;英语，2013）。 MSCs被认为是源于与骨髓和各种组织内脉管系统内皮细胞相关的周细胞（Sacchetti et al。，2007; Crisan et al。，2008）。这种独特的血管周围位置将它们置于血流中的炎症和其他可溶性因子附近，使其监测系统信号。事实上，将壁壁细胞募集到内皮是血管成熟的关键事件，周细胞在血管维持和完整性中起关键作用（Benjamin et al。，1998; ...
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