| Candida albicans Agar Invasion Assays
|
|
Author:
Date:
2020-08-20
[Abstract] The ability of the human fungal pathogen Candida albicans to disseminate into tissues is promoted by a switch from budding to invasive hyphal growth. This morphological transition is stimulated by multiple environmental factors that can vary at different sites of infection. To identify genes that promote invasive growth, C. albicans mutants can be screened for defects in growing invasively into solid agar medium as a substitute for studying tissue invasion. This in vitro approach has advantages in that it permits the media conditions to be varied to mimic different host environments. In addition, the concentration of agar can be varied to determine the effects of altering the rigidity of the matrix into which the cells invade, as this provides a better indicator ...
[摘要] [摘要 ] 人类真菌病原体白色念珠菌传播到组织的能力是由从发芽到侵入性菌丝生长的转换而增强的。多种环境因素可能会刺激这种形态转变，这些环境因素可能在不同的感染部位有所不同。为了鉴定促进侵入growt基因小时，白色念珠菌突变体可以在侵入性生长成固体琼脂培养基作为研究组织侵袭的替代品进行筛选的缺陷。这个体外 该方法的优点在于，它允许改变媒体条件以模仿不同的主机环境。另外，可以改变琼脂的浓度以确定改变细胞侵袭的基质的刚度的作用，因为与液体培养中形成菌丝的能力相比，这提供了更好的侵袭性生长指标。在多种条件下的测试可以用来鉴定具有最强缺陷的突变细胞。因此，将描述用于分析白色念珠菌在不同条件下的侵袭性生长的方案和培养基，其适合于测试突变株白色念珠菌菌株的单个菌株或高通量分析。
[背景 ] 白色念珠菌是一种多形性真菌病原体，可以通过形成芽（小球形细胞），假菌丝细胞（细长细胞链）或菌丝细胞（具有平行平行线的长丝状细胞链）生长（图1）（贵族等人，2017）。已证明宿主中遇到的多种环境刺激可促进向侵袭性生长的转变，包括人体温度（37 °C ），碱性pH，CO 2 ，血清中的因子和糖GlcNAc（N-乙酰氨基葡萄糖） ）（Kornitzer，2019）。萌芽细胞被认为促进胃肠道的血流传播和定植（Pierce和Kumamoto ，2012 ；Witchley ...
|
|
|
| Flow Cytometric Quantification of Fatty Acid Uptake by Mycobacterium tuberculosis in Macrophages
|
|
Author:
Date:
2018-02-20
[Abstract] Mycobacterium tuberculosis (Mtb) has evolved to assimilate fatty acids from its host. However, until recently, there was no reliable way to quantify fatty acid uptake by the bacteria during host cell infection. Here we describe a new method to quantify fatty acid uptake by intracellular bacilli. We infect macrophages with Mtb constitutively expressing mCherry and then metabolically label them with Bodipy-palmitate. Following the labeling procedure, we isolate Mtb-containing phagosomes on a sucrose cushion and disrupt the phagosomes with detergent. After extensive washes, the isolated bacteria are analyzed by flow cytometry to determine the level of Bodipy-palmitate signal associated with the bacteria. Using a Mtb mutant strain defective in fatty acid uptake in liquid culture we ...
[摘要] 结核分枝杆菌（Mtb）已经发展为从其宿主吸收脂肪酸。然而，直到最近，还没有可靠的方法来量化宿主细胞感染期间细菌对脂肪酸的摄取。在这里，我们描述了一种新的方法来量化细胞内杆菌对脂肪酸的摄取。我们用Mtb组成性表达mCherry感染巨噬细胞，然后用Bodipy-palmitate代谢标记它们。标记程序后，我们在蔗糖垫上分离含有Mtb的吞噬体，并用去污剂破坏吞噬体。大量洗涤后，通过流式细胞术分析分离的细菌以确定与细菌相关的Bodipy-棕榈酸酯信号的水平。使用液体培养物中脂肪酸摄取缺陷的Mtb突变株，我们确定该突变体在巨噬细胞感染期间同化比野生型菌株少10倍的Bodipy-棕榈酸酯。脂肪酸摄取的这种定量方法可用于进一步鉴定参与细胞内Mtb和可能的其他细菌的脂质摄取的途径。
【背景】结核分枝杆菌（Mtb）同化宿主来源的脂质（脂肪酸和胆固醇）的能力使得病原体能够在其宿主内存活（Russell等人，2010; Lovewell 等人，2016）。在小鼠感染期间和在人肺组织中，通过巨噬细胞内的Mtb上调胆固醇和脂肪酸代谢相关基因来支持该想法（Schnappinger等人，2003; Rachman等人，2006; Rohde等人，2007;Fontán等人，2008; Tailleux等人，2008; Homolka et al。，2010; Rohde et ...
|
|
|