这项工作是支持的萨班研究所前博士后奖（PMDM），由NIH RO1 HL75773（DW）。

机关文化是一个非常有用的和通用的技术来研究基因和蛋白表达。这些体外培养的方法，可以用来作为初步或补充体内研究。 1。人胚肺隔离<ol><li>定时孕鼠的CO 2麻醉处死postcoitum每天11.5或12.5（E11.5 - 12.5）根据美国国立卫生研究院和OLAW指引。动物被放置在一腔，和100％的CO 2介绍。后的动物是无意识的CO 2流量增加。临床死亡的动物必须得到保证。 </li><li>以下步骤需要在无菌层流罩条件下完成。子宫是从怀孕的女性。要删除从动物的子宫，怀孕的女性被放置在他们的后面，喷以70％的乙醇。切口在腹部，皮肤是由皮肤向上拉，同时动物的后腿删除。打开腹腔和子宫是从动物中删除。 </li><li>血是放置在一个充满冷汉克斯平衡盐溶液（HBSS）50 ml锥形管的子宫冲洗掉，并管轻轻摇晃2分钟。 </li><li>子宫立体解剖显微镜下，然后放置在培​​养皿和发布使用弹簧剪刀切开子宫壁的胚胎从子宫。收获的胚胎，使用一个穿孔勺子，并在冰上放置在一个新的Petri菜含有的HBSS。 </li><li>立体解剖显微镜下，胚胎肺解剖冷的HBSS（图1）在培养皿菜之一。 </li><li>分离出胚胎肺是一个Petri菜含有的HBSS使用无菌移液管放在冰上。 </li></ol> 2。人胚肺文化<ol><li> 500微升至1毫升，每口井的D-MEM/F-12 50个单位/毫升的青霉素，链霉素的补充，增加了一个Nunclon聚苯乙烯盘。 </li><li>一个Nuclepore聚碳酸酯轨道蚀刻膜是放在媒体上。当Nuclepore聚碳酸酯履带式蚀刻膜放在媒体上，确保有光泽的一面是对媒体，和粗糙的一面朝上。 </li><li> Nuclepore聚碳酸酯轨道蚀刻膜使用无菌移液管上放置一个解剖的胚胎肺。 </li><li>使用镊子胚胎肺的位置调整。胚胎肺放置在过滤器上应该有一个完整的气管，并放置他们的气管内有一条直线的位置，从而使所有的肺部有相同的内部压力。 </li><li> Nunclon聚苯乙烯菜是在细胞培养箱（图2）所需的培养时间为转移。 </li></ol> 3。材料 1。胚胎全肺隔离<ol><li>定时怀孕（C57BL6野生型或转基因）postcoitum每天11.5 13.5（E11.5 - 13.5）牺牲的小鼠。 </li><li>汉克斯“平衡盐溶液（HBSS）（1X），液体，无氯化钙，氯化镁，硫酸镁。 （Invitrogen公司，卡尔斯巴德，加利福尼亚州），辅以50个单位/毫升的青霉素，链霉素（Invitrogen公司，卡尔斯巴德，加利福尼亚州）。在室温下储存在4 ° C开盘后的HBSS。分装和储存在-20 ° C的青霉素，链霉素</li><li>立体解剖显微镜（莱卡，韦茨拉尔，德国）。 </li><li>解剖工具，包括杜蒙钳，细虹膜剪刀（直），诺伊斯弹簧剪刀和莫里亚®汤匙（穿孔）（精细的科学工具，福斯特城，加利福尼亚州）。 </li></ol> 2。胚胎全肺文化<ol><li>贝科的改良Eagle中等：营养组合的F - 12（D-MEM/F-12）（1X），液体，1:1包含L -谷氨酰胺，但没有HEPES缓冲液。 （Invitrogen公司，卡尔斯巴德，加利福尼亚州），辅以50个单位/毫升的青霉素，链霉素（Invitrogen公司，卡尔斯巴德，加利福尼亚州）。保持DMEM/F-12瓶远离光线（如铝箔覆盖）4和存储° C。分装和储存在-20 ° C的青霉素，链霉素</li><li> Nuclepore聚碳酸酯轨道蚀刻膜，8.0米，13毫米（的Whatman Nuclepore履带式蚀刻膜（滤纸，弗洛厄姆公园，新泽西州）。 </li><li> Nunclon聚苯乙烯有盖菜，4口井（罗切斯特，纽约）。 </li><li>一次性转让的吸液管，无菌（尔科技，匹兹堡，宾夕法尼亚州）。 </li></ol><img src="/files/ftp_upload/2035/2035fig1.jpg" alt="图1" /> 图1。 E12的胚胎肺的剖析 。 （一）从右侧查看E12.5全胚胎（B）右前肢已经从胚胎中删除（C）钳的左手拿着手在盘中持稳胚胎举行。箭头指示（四）胚胎肺在于心（删除后的清扫计划）和前向脊柱。此图显示肺部后，皮肤和摘取心脏，（五 ）咽清除允许从胚胎中分离完整的肺。（F）的额外咽部组织和食道已被削去。解剖E12.5胚胎肺完整的气管和喉部所示。颅叶（CR），（MED）内侧叶，（CA）尾鳍叶，配件（ACC）叶（LE）的左叶。 <img src="/files/ftp_upload/2035/2035fig2.jpg" alt="图2" /> 图2。FGF9诱导间质细胞和上皮细胞在体外生长的肺扩张的扩张（AC）E12.5肺FGF9的情况下在48小时生长。注意：在分支的增加。增长48小时（DF）的E12.5肺FGF9的存在。请注意，扩张的上皮细胞和间质细胞后24小时的文化（五）早。 48小时后（女），上皮细胞的影响更为明显。比例尺：自动对焦400微米4。 这个实验方法的完整的文本<a href="http://springerprotocols.com/Abstract/doi/10.1007/978-1-59745-019-5_5">协议，</a>在斯普林格协议。

<ol>
	<li>Alescio, T., Cassini, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+in+vitro+of+tracheal+buds+by+pulmonary+mesenchyme+grafted+on+tracheal+epithelium.">Induction in vitro of tracheal buds by pulmonary mesenchyme grafted on tracheal epithelium.</a> J Exp Zool. 150, 83-94 (1962).</li><li>Warburton, D., Schwarz, M., Tefft, D., Flores-Delgado, G., Anderson, K. D., Cardoso, W. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+molecular+basis+of+lung+morphogenesis.">The molecular basis of lung morphogenesis.</a> Mech Dev. 92, 55-81 (2000).</li><li>Spooner, B. S., Hardman, P., Paulsen, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gravity+in+mammalian+organ+development:+differentiation+of+cultured+lung+and+pancreas+rudiments+during+spaceflight.">Gravity in mammalian organ development: differentiation of cultured lung and pancreas rudiments during spaceflight.</a> J Exp Zool. 269, 212-222 (1994).</li><li>Moral, d. e. l., M, P., De Langhe, S. P., Sala, F. G., Veltmaat, J. M., Tefft, D., Wang, K., Warburton, D., Bellusci, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+role+of+FGF9+on+epithelium+and+mesenchyme+in+mouse+embryonic+lung.">Differential role of FGF9 on epithelium and mesenchyme in mouse embryonic lung.</a> Dev Biol. 293, 77-89 (2006).</li><li>Moral, D. e. l., M, P., Sala, F. G., Tefft, D., Shi, W., Keshet, E., Bellusci, S., Warburton, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=VEGF-A+signaling+through+Flk-1+is+a+critical+facilitator+of+early+embryonic+lung+epithelial+to+endothelial+crosstalk+and+branching+morphogenesis.">VEGF-A signaling through Flk-1 is a critical facilitator of early embryonic lung epithelial to endothelial crosstalk and branching morphogenesis.</a> Dev Biol. 290, 177-188 (2006).</li><li>Jaskoll, T. F., Don-Wheeler, G., Johnson, R., Slavkin, H. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Embryonic+mouse+lung+morphogenesis+and+type+II+cytodifferentiation+in+serumless,+chemically+defined+medium+using+prolonged+in+vitro+cultures.">Embryonic mouse lung morphogenesis and type II cytodifferentiation in serumless, chemically defined medium using prolonged in vitro cultures.</a> Cell Differ. 24, 105-117 (1988).</li><li>Seth, R., Shum, L., Wu, F., Wuenschell, C., Hall, F. L., Slavkin, H. C., Warburton, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+epidermal+growth+factor+expression+in+early+mouse+embryo+lung+branching+morphogenesis+in+culture:+antisense+oligodeoxynucleotide+inhibitory+strategy.">Role of epidermal growth factor expression in early mouse embryo lung branching morphogenesis in culture: antisense oligodeoxynucleotide inhibitory strategy.</a> Dev Biol. 158, 555-559 (1993).</li></ol>

mouse embryonic lung culture, a system to evaluate the molecular mechanisms of branching

原始龙的规格以及分支形态发生和各种肺细胞谱系的形成需要一个与周围的间质细胞和间皮肺胚层的具体互动。肺间质已被证明是肺分支形态发生归纳信号源。上皮 - 间质皮的相互作用也胚胎肺的形态发生的关键。早期胚胎肺器官培养是一个非常有用的的系统研究上皮 - 间质相互作用。可以很容易地在这个系统中操纵（产妇的影响力和血流量的情况下）的特定条件下，上皮和间质的形态发生的收益。更重要的是，这种技术可以很容易地在一个serumless，化学定义的文化传媒。利用表达的蛋白，重组病毒载体和/或分析，反义RNA的转基因小鼠品系，以及RNA干扰基因敲除，可以实现增益和功能丧失。

Watch this Scientific Journal Video about Mouse Embryonic Lung Culture, A System to Evaluate the Molecular Mechanisms of Branching at JoVE.com

Mouse Embryonic Lung Culture, A System to Evaluate the Molecular Mechanisms of Branching

早期胚胎肺器官培养是一个非常有用的的系统研究上皮 - 间质相互作用。上皮和间质的形态发生的具体条件下，可以很容易地在这个系统中操纵收益。

小鼠胚胎的龙文化，一个系统来评价分枝的分子机制

Lung primordial specification as well as branching morphogenesis, and the formation of various pulmonary cell lineages requires a specific interaction of ...

mouse-embryonic-lung-culture-system-to-evaluate-molecular-mechanisms

Research

JoVE Journal

Biology

18.3K 次观看.  Childrens Hospital Los Angeles. 早期胚胎肺器官培养是一个非常有用的的系统研究上皮 - 间质相互作用。上皮和间质的形态发生的具体条件下，可以很容易地在这个系统中操纵收益。

视频: Mouse Embryonic Lung Culture, A System to Evaluate the Molecular Mechanisms of Branching

Isolation and Culture of Cells from the Nephrogenic Zone of the Embryonic Mouse Kidney

Embryonic development of the kidney has been extensively studied both as a model for epithelial-mesenchymal interaction in organogenesis and to gain understanding of the origins of congenital kidney disease. More recently, the possibility of steering na&iuml;ve embryonic stem cells toward nephrogenic fates has been explored in the emerging field of regenerative medicine. Genetic studies in the mouse have identified several pathways required for kidney development, and a global catalog of gene transcription in the organ has recently been generated <a href="http://www.gudmap.org/">http://www.gudmap.org/</a>, providing numerous candidate regulators of essential developmental functions. Organogenesis of the rodent kidney can be studied in organ culture, and many reports have used this approach to analyze outcomes of either applying candidate proteins or knocking down the expression of candidate genes using siRNA or morpholinos. However, the applicability of organ culture to the study of signaling that regulates stem/progenitor cell differentiation versus renewal in the developing kidney is limited as cultured organs contain a compact extracellular matrix limiting diffusion of macromolecules and virus particles. To study the cell signaling events that influence the stem/progenitor cell niche in the kidney we have developed a primary cell system that establishes the nephrogenic zone or progenitor cell niche of the developing kidney ex vivo in isolation from the epithelial inducer of differentiation. Using limited enzymatic digestion, nephrogenic zone cells can be selectively liberated from developing kidneys at E17.5. Following filtration, these cells can be cultured as an irregular monolayer using optimized conditions. Marker gene analysis demonstrates that these cultures contain a distribution of cell types characteristic of the nephrogenic zone in vivo, and that they maintain appropriate marker gene expression during the culture period. These cells are highly accessible to small molecule and recombinant protein treatment, and importantly also to viral transduction, which greatly facilitates the study of candidate stem/progenitor cell regulator effects. Basic cell biological parameters such as proliferation and cell death as well as changes in expression of molecular markers characteristic of nephron stem/progenitor cells in vivo can be successfully used as experimental outcomes. Ongoing work in our laboratory using this novel primary cell technique aims to uncover basic mechanisms governing the regulation of self-renewal versus differentiation in nephron stem/progenitor cells.

In this report we describe a method for the isolation and culture of the progenitor cell niche from the embryonic mouse kidney that can be used to study signaling pathways regulating stem/progenitor cells of the developing kidney. These cultured cells are highly accessible to small molecule and recombinant protein treatment, and importantly also to viral transduction, which allows efficient manipulation of candidate pathways.

从小鼠胚胎肾肾区细胞的分离和培养

Embryonic development of the kidney has been extensively studied both as a model for epithelial-mesenchymal interaction in organogenesis and  to gain ...

科研

生物学

Whole-mount Immunohistochemical Analysis for Embryonic Limb Skin Vasculature: a Model System to Study Vascular Branching Morphogenesis in Embryo

Whole-mount immunohistochemical analysis for imaging the entire vasculature is pivotal for understanding the cellular mechanisms of branching morphogenesis. We have developed the limb skin vasculature model to study vascular development in which a pre-existing primitive capillary plexus is reorganized into a hierarchically branched vascular network. Whole-mount confocal microscopy with multiple labelling allows for robust imaging of intact blood vessels as well as their cellular components including endothelial cells, pericytes and smooth muscle cells, using specific fluorescent markers. Advances in this limb skin vasculature model with genetic studies have improved understanding molecular mechanisms of vascular development and patterning. The limb skin vasculature model has been used to study how peripheral nerves provide a spatial template for the differentiation and patterning of arteries. This video article describes a simple and robust protocol to stain intact blood vessels with vascular specific antibodies and fluorescent secondary antibodies, which is applicable for vascularized embryonic organs where we are able to follow the process of vascular development.

We introduce a whole-mount immunohistochemistry and laser scanning confocal microscopy with multiple labelling for analyzing intricate vascular network formation in mouse embryonic limb skin.

全安装胚胎肢体皮肤血管的免疫组织化学分析：一个模型系统，研究在胚胎血管分支形态发生

Whole-mount immunohistochemical analysis for imaging the entire vasculature is pivotal for understanding the cellular mechanisms of branching ...

RNAi Screening to Identify Postembryonic Phenotypes in C. elegans

C. elegans has proven to be a valuable model system for the discovery and functional characterization of many genes and gene pathways1. More sophisticated tools and resources for studies in this system are facilitating continued discovery of genes with more subtle phenotypes or roles. 
Here we present a generalized protocol we adapted for identifying C. elegans genes with postembryonic phenotypes of interest using RNAi2. This procedure is easily modified to assay the phenotype of choice, whether by light or fluorescence optics on a dissecting or compound microscope. This screening protocol capitalizes on the physical assets of the organism and molecular tools the C. elegans research community has produced. As an example, we demonstrate the use of an integrated transgene that expresses a fluorescent product in an RNAi screen to identify genes required for the normal localization of this product in late stage larvae and adults. First, we used a commercially available genomic RNAi library with full-length cDNA inserts. This library facilitates the rapid identification of multiple candidates by RNAi reduction of the candidate gene product. Second, we generated an integrated transgene that expresses our fluorecently tagged protein of interest in an RNAi-sensitive background. Third, by exposing hatched animals to RNAi, this screen permits identification of gene products that have a vital embryonic role that would otherwise mask a post-embryonic role in regulating the protein of interest. Lastly, this screen uses a compound microscope equipped for single cell resolution.

RNAi Screening to Identify Postembryonic Phenotypes in C. elegans

We describe a sensitized method to identify postembryonic regulators of protein expression and localization in C. elegans using an RNAi-based genomic screen and an integrated transgene that expresses a functional, fluorescently tagged protein.

RNAi筛选识别胚后的表型 C。线虫</em

C. elegans has proven to be a valuable model system for the discovery and functional characterization of many genes and gene pathways1. More sophisticated ...

A System for ex vivo Culturing of Embryonic Pancreas

The pancreas controls vital functions of our body, including the production of digestive enzymes and regulation of blood sugar levels1. Although in the past decade many studies have contributed to a solid foundation for understanding pancreatic organogenesis, important gaps persist in our knowledge of early pancreas formation2. A complete understanding of these early events will provide insight into the development of this organ, but also into incurable diseases that target the pancreas, such as diabetes or pancreatic cancer. Finally, this information will generate a blueprint for developing cell-replacement therapies in the context of diabetes.
 During embryogenesis, the pancreas originates from distinct embryonic outgrowths of the dorsal and ventral foregut endoderm at embryonic day (E) 9.5 in the mouse embryo3,4. Both outgrowths evaginate into the surrounding mesenchyme as solid epithelial buds, which undergo proliferation, branching and differentiation to generate a fully mature organ2,5,6. Recent evidences have suggested that growth and differentiation of pancreatic cell lineages, including the insulin-producing &beta;-cells, depends on proper tissue-architecture, epithelial remodeling and cell positioning within the branching pancreatic epithelium7,8. However, how branching morphogenesis occurs and is coordinated with proliferation and differentiation in the pancreas is largely unknown. This is in part due to the fact that current knowledge about these developmental processes has relied almost exclusively on analysis of fixed specimens, while morphogenetic events are highly dynamic.
 Here, we report a method for dissecting and culturing mouse embryonic pancreatic buds ex vivo on glass bottom dishes, which allow direct visualization of the developing pancreas (Figure 1). This culture system is ideally devised for confocal laser scanning microscopy and, in particular, live-cell imaging. Pancreatic explants can be prepared not only from wild-type mouse embryos, but also from genetically engineered mouse strains (e.g. transgenic or knockout), allowing real-time studies of mutant phenotypes. Moreover, this ex vivo culture system is valuable to study the effects of chemical compounds on pancreatic development, enabling to obtain quantitative data about proliferation and growth, elongation, branching, tubulogenesis and differentiation. In conclusion, the development of an ex vivo pancreatic explant culture method combined with high-resolution imaging provides a strong platform for observing morphogenetic and differentiation events as they occur within the developing mouse embryo.

A System for ex vivo Culturing of Embryonic Pancreas

Here, we describe a method for isolation, culture and manipulation of mouse embryonic pancreas. This represents an excellent ex vivo system for studying various aspects of pancreatic development, including morphogenesis, differentiation and growth. Pancreatic bud explants can be cultured for several days and used in a range of different applications, including whole-mount immunofluorescence and live imaging.

一个系统<em&gt;体外</em培养的胚胎胰腺

The pancreas controls vital functions of our body,  including the production of digestive enzymes and regulation of blood sugar  levels1. Although in the ...

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 ...

Mouse Embryonic Development in a Serum-free Whole Embryo Culture System

Mid-gestation stage mouse embryos were cultured utilizing a serum-free culture medium prepared from commercially available stem cell media supplements in an oxygenated rolling bottle culture system. Mouse embryos at E10.5 were carefully isolated from the uterus with intact yolk sac and in a process involving precise surgical maneuver the embryos were gently exteriorized from the yolk sac while maintaining the vascular continuity of the embryo with the yolk sac. Compared to embryos prepared with intact yolk sac or with the yolk sac removed, these embryos exhibited superior survival rate and developmental progression when cultured under similar conditions. We show that these mouse embryos, when cultured in a defined medium in an atmosphere of 95% O2 / 5% CO2 in a rolling bottle culture apparatus at 37 &#176;&#8203;C for 16-40 hr, exhibit morphological growth and development comparable to the embryos developing in utero. We believe this method will be useful for investigators needing to utilize whole embryo culture to study signaling interactions important in embryonic organogenesis.

Serum utilized in embryo cultures contains unknown components that can affect the outcome of experiments especially in studies involving signaling interactions. Here we utilized a serum-free oxygenated culture system and show that mid-gestation mouse embryos cultured for 16-40 hr&#160;exhibit morphological development comparable to embryos developing in utero.

鼠胚体外发育无血清全胚胎培养系统

Mid-gestation stage mouse embryos were cultured utilizing a serum-free culture medium prepared from commercially available stem cell media supplements in ...

Procedure to Evaluate the Efficiency of Flocculants for the Removal of Dispersed Particles from Plant Extracts

Plants are important to humans not only because they provide commodities such as food, feed and raw materials, but increasingly because they can be used as manufacturing platforms for added-value products such as biopharmaceuticals. In both cases, liquid plant extracts may need to be clarified to remove particulates. Optimal clarification reduces the costs of filtration and centrifugation by increasing capacity and longevity. This can be achieved by introducing charged polymers known as flocculants, which cross-link dispersed particles to facilitate solid-liquid separation. There are no mechanistic flocculation models for complex mixtures such as plant extracts so empirical models are used instead. Here a design-of-experiments procedure is described that allows the rapid screening of different flocculants, optimizing the clarification of plant extracts and significantly reducing turbidity. The resulting predictive models allow the identification of robust process conditions and sets of polymers with complementary properties, e.g. effective flocculation in extracts with specific conductivities. The results presented for tobacco leaf extracts can easily be adapted to other plant species or tissues and will thus facilitate the development of more cost-effective downstream processes for commodities and plant-derived pharmaceuticals.

The design-of-experiments procedure presented here allows the evaluation of different flocculants in terms of their ability to aggregate dispersed particles in plant extracts, thus reducing turbidity and the costs of downstream processing.

过程评价絮凝剂的效率的分散粒子的从植物提取物的去除

Plants are important to humans not only because they provide commodities such as food, feed and raw materials, but increasingly because they can be used ...

High Content Screening Analysis to Evaluate the Toxicological Effects of Harmful and Potentially Harmful Constituents (HPHC)

Cigarette smoke (CS) is a major risk factor for cardiovascular and lung diseases. Because CS is a complex aerosol containing more than 7,000 chemicals1 it is challenging to assess the contributions of individual constituents to its overall toxicity. Toxicological profiles of individual constituents as well as mixtures can be however established in vitro, by applying high through-put screening tools, which enable the profiling of Harmful and Potentially Harmful Constituents (HPHCs) of tobacco smoke, as defined by the U.S. Food and Drug Administration (FDA).2
For an initial assessment, an impedance-based instrument was used for a real-time, label-free assessment of the compound&#39;s toxicity. The instrument readout relies on cell adhesion, viability and morphology that all together provide an overview of the cell status. A dimensionless parameter, named cell index, is used for quantification. A set of different staining protocols was developed for a fluorescence imaging-based investigation and a HCS platform was used to gain more in-depth information on the kind of cytotoxicity elicited by each HPHC.
Of the 15 constituents tested, only five were selected for HCS-based analysis as they registered a computable LD50 (&#60; 20 mM). These included 1-aminonaphtalene, Arsenic (V), Chromium (VI), Crotonaldehyde and Phenol. Based on their effect in the HCS, 1-aminonaphtalene and Phenol could be identified to induce mitochondrial dysfunction, and, together with Chromium (VI) as genotoxic based on the increased histone H2AX phosphorylation. Crotonaldehyde was identified as an oxidative stress inducer and Arsenic as a stress kinase pathway activator.
This study demonstrates that a combination of impedance-based and HCS technologies provides a robust tool for in vitro assessment of CS constituents.

High Content Screening Analysis to Evaluate the Toxicological Effects of Harmful and Potentially Harmful Constituents HPHC

The objective of the study was to assess the biological impact of 15 cigarette smoke constituents using a combination of an impedance-based real time cell analyzer and a high-content screening (HCS)-based platform for toxicological assessment in vitro. This study provides information on effective doses, toxicity and modes of action of the tested compounds.

高内涵筛选分析法评价有害和潜在有害成分的毒性效应（HPHC）

Cigarette smoke (CS) is a major risk factor for cardiovascular and lung diseases. Because CS is a complex aerosol containing more than 7,000 chemicals1 it ...

Mucin Agarose Gel Electrophoresis: Western Blotting for High-molecular-weight Glycoproteins

Mucins, the heavily-glycosylated proteins lining mucosal surfaces, have evolved as a key component of innate defense by protecting the epithelium against invading pathogens. The main role of these macromolecules is to facilitate particle trapping and clearance while promoting lubrication of the mucosa. During protein synthesis, mucins undergo intense O-glycosylation and multimerization, which dramatically increase the mass and size of these molecules. These post-translational modifications are critical for the viscoelastic properties of mucus. As a result of the complex biochemical and biophysical nature of these molecules, working with mucins provides many challenges that cannot be overcome by conventional protein analysis methods. For instance, their high-molecular-weight prevents electrophoretic migration via regular polyacrylamide gels and their sticky nature causes adhesion to experimental tubing. However, investigating the role of mucins in health (e.g., maintaining mucosal integrity) and disease (e.g., hyperconcentration, mucostasis, cancer) has recently gained interest and mucins are being investigated as a therapeutic target. A better understanding of the production and function of mucin macromolecules may lead to novel pharmaceutical approaches, e.g., inhibitors of mucin granule exocytosis and/or mucolytic agents. Therefore, consistent and reliable protocols to investigate mucin biology are critical for scientific advancement. Here, we describe conventional methods to separate mucin macromolecules by electrophoresis using an agarose gel, transfer protein into nitrocellulose membrane, and detect signal with mucin-specific antibodies as well as infrared fluorescent gel reader. These techniques are widely applicable to determine mucin quantitation, multimerization and to test the effects of pharmacological compounds on mucins.

Mucins are high-molecular-weight glycoconjugates, with size ranging from 0.2 to 200 megadalton (MDa). As a result of their size, mucins do not penetrate conventional polyacrylamide gels and require larger pores for separation. We provide a detailed protocol for mucin agarose gel electrophoresis to assess relative quantification and study polymer assembly.

粘蛋白琼脂糖凝胶电泳：蛋白质印迹高分子量糖蛋白


Mucins, the heavily-glycosylated proteins lining mucosal surfaces, have evolved as a key component of innate defense by protecting the epithelium against ...