这部分工作是由中国船舶重工集团公司（I + D项目C022）和PEDECI​​BA支持。作者要感谢玛丽拉博拉蒂和瓦伦蒂娜普罗图1从细胞生物学部（巴斯德研究所蒙得维的亚）慷慨协作有关MoFlo的细胞分选，轻轻提供在这个项目中使用的所有豚鼠标本梅里亚蒙得维的亚。转载BioMed Central的许可; 图2和图3，表1与许可S.卡格尔AG，巴塞尔和图4和图5分别与约翰·威利父子公司（版权拥有者许可，复制或改编威利-布莱克韦尔，2011）。

1。细胞悬液的制备<ol><li> IACUC或同等专业委员会（乌拉圭全国委员会动物实验的建议使用牺牲标本[CNEA）。在我们的情况下，过量的巴比妥给药。 </li><li>解剖睾丸标准批准程序后，将它们放置在一个96毫米的玻璃培养皿上冰，冰冷的DMEM含10毫升辅以10％胎牛血清。 </li><li>删除白膜和削减解封的睾丸，每侧的2 - 3毫米见方的小块。 </li><li>然后，这些碎片被处理在Medimachine，自动机械粉碎机组织里面含有穿孔的不锈钢屏幕和金属转子一次性单位分类。要做到这一点，将1毫升冷补充DMEM和4 - 5这些作品在一个50微米的可支配单位，开关disaggregator，和过程<html> 50秒后，从制造商的简单说明。 </li><li>回收得到的细胞悬浮液从分解单元，使用3 - 5毫升注射器不带针。 </li><li>过滤50微米的尼龙网，用0.5毫升浸泡补充DMEM。 </li><li>再次过滤悬浮液浸泡25微米尼龙网，置于冰上。 </li><li>计数在纽鲍室，并调节细胞浓度为1 - 2×10 7个细胞/ ml的DMEM培养液补充。至少为4×10 7个细胞/克睾丸材料是通常获得。 </li><li>最后，添加NDA（2 - 萘酚-6,8 - 二磺酸二钾盐）至终浓度为0.2％，以防止细胞聚集。 </li><li>与市售的动物细胞的生存能力套件可选:检查睾丸细胞悬液的细胞活力，按照制造商的说明。 </li></ol> 2。流式细胞仪分析ve_content"&gt;我们已经使用了流式细胞 - 迪金森FACSVantage流式细胞仪配备调谐发射波长为488 nm的用于分析的细胞与高浓度的碘化丙啶（PI）染色与相干的氩离子激光（未定影的PI的入口进入的问题。细胞在压力下已经解决别处9,10）。 <ol><li> PI染色，在终浓度为50μg/ ml的细胞悬浮液中添加荧光染料，孵育10分钟，在0℃下在黑暗中。 </li><li>激光功率设定为100毫瓦和一个26分之575的带通滤波器是用来收集PI发出的荧光在丙级。 </li><li>我们执行FC测量一个70微米的喷嘴。排序精母细胞群体，在正常-R或-C正常排序模式，使用3排序滴在信封。样品和收集管保持在3 - 4℃，使用制冷机组。调整样品的差来分析细胞的速度为500〜1500，每秒。 </li><li>使用分析应用CellQuest软件（BD）以下参数:前向散射（FSC-H），侧向散射光（SSC-H），总发射的荧光或脉冲面积（FL2-A）和荧光发射的持续时间或脉冲宽度（FL2-W）。 </li></ol>或者，我们所采用的重要染料Hoechst 33342至终浓度为5微克/毫升，并温育10分钟，在37℃下在黑暗中。进行细胞分析装置的一个:流式细胞仪MoFlo（DakoCytomation）配备在25毫瓦的UV激发波长激光器的工作，使用70微米的喷嘴。数据操作进行与峰会V4.3的软件（DakoCytomation）。

<ol>
	<li>Meistrich, M. L., Prescott, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Separation+of+spermatogenic+cells+and+nuclei+from+rodent+testes.">Separation of spermatogenic cells and nuclei from rodent testes.</a> Methods of Cell Biology. 15, 15-54 (1977).</li><li>Lam, D. M. K., Furrer, R., Bruce, W. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+separation,+physical+characterization,+and+differentiation+kinetics+of+spermatogonial+cells+of+the+mouse.">The separation, physical characterization, and differentiation kinetics of spermatogonial cells of the mouse.</a> Proc. Natl. Acad. Sci. USA. 65, 192-199 (1970).</li><li>Romrell, L. J., Bellve, A. R., Fawcet, 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=Separation+of+mouse+spermatogenic+cells+by+sedimentation+velocity.">Separation of mouse spermatogenic cells by sedimentation velocity.</a> Dev. Biol. 19, 119-131 (1976).</li><li>Geisinger, A., Rodr&#237;guez-Casuriaga, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+cytometry+for+gene+expression+studies+in+mammalian+spermatogenesis.">Flow cytometry for gene expression studies in mammalian spermatogenesis.</a> Cytogenet. Genome Res. 128, 46-56 (2010).</li><li>Getun, I. V., Torres, B., Bois, P. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+cytometry+purification+of+mouse+meiotic+cells.">Flow cytometry purification of mouse meiotic cells.</a> J. Vis. Exp. (50), e2602 (2011).</li><li>Meistrich, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Separation+of+mouse+spermatogenic+cells+by+velocity+sedimentation.">Separation of mouse spermatogenic cells by velocity sedimentation.</a> J. Cell Physiol. 80, 299-312 (1972).</li><li>Meistrich, M. L., Bruce, W. R., Clermont, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+composition+of+fractions+of+mouse+testis+cells+following+velocity+sedimentation+separation.">Cellular composition of fractions of mouse testis cells following velocity sedimentation separation.</a> Exp. Cell Res. 79, 213-227 (1973).</li><li>Malkov, M., Fisher, Y., Don, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Developmental+schedule+of+the+postnatal+rat+testis+determined+by+flow+cytometry.">Developmental schedule of the postnatal rat testis determined by flow cytometry.</a> Biol. Rep. 59, 84-92 (1998).</li><li>Rodr&#237;guez-Casuriaga, R., Geisinger, A., Santi&#241;aque, F., L&#243;pez, B., Folle, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-purity+flow+sorting+of+early+meiocytes+based+on+DNA+analysis+of+guinea+pig+spermatogenic+cells.">High-purity flow sorting of early meiocytes based on DNA analysis of guinea pig spermatogenic cells.</a> Cytometry A. 79, 625-634 (2011).</li><li>Davey, H. M., Hexley, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Red+but+not+dead?+Membranes+of+stressed+Saccharomyces+cerevisiae+are+permeable+to+propidium+iodide.">Red but not dead? Membranes of stressed Saccharomyces cerevisiae are permeable to propidium iodide.</a> Environ. Microbiol. 13, 163-171 (2011).</li><li>Rodr&#237;guez-Casuriaga, R., Geisinger, A., L&#243;pez-Carro, B., Porro, V., Wettstein, R., Folle, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultra-fast+and+optimized+method+for+the+preparation+of+rodent+testicular+cells+for+flow+cytometric+analysis.">Ultra-fast and optimized method for the preparation of rodent testicular cells for flow cytometric analysis.</a> Biol. Proced. Online. 11, 184-195 (2009).</li><li>Span&#242;, M., Evenson, D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+cytometric+analysis+for+reproductive+biology.">Flow cytometric analysis for reproductive biology.</a> Biol Cell. 78, 53-62 (1993).</li></ol>

这里描述的优化方法使细胞悬液的制备从啮齿动物睾丸组织在一个非常快速和可重复的方式，避免了酶和洗涤剂处理和维护良好的细胞的完整性和类型比例。的简洁的程序（跨度15分钟包括睾丸切除，组织切割和处理），涉及最少的处理，酶处理的情况下的一些主要优点。所有这些将占短暂的生命大分子保存好，这是关键的时候，具有代表性的化合物存在于原始细胞人口需要。 关于使用PI或赫斯特33342，流式细胞仪分析睾丸细胞悬液的就业或其他染料产生的配置文件中，我们已经观察无明显差异。染料的选择，更取决于用户的喜好和空房，计划进一步利用。的一侧上，PI是便宜的，广泛的应用，不要求使用流式细胞仪和分选机，具有紫外激光。另一方面，虽然我们已经成功地使用PI染色细胞不可告人的排序和基因差异表达的研究（ 图4），赫斯特33342或低毒性水平的另一个重要的染料，可能是最好的选择，应用全细胞活力，如生殖细胞培养和/或移植4。 我们已经能够实现超过95％的纯度，或者与不同的DNA含量4（ 图3）对选定的睾丸人口分类，特定的细胞群，或什至具有相同的的DNA内容，但不同的染色质凝集的水平（ 图4）的亚群。只要感兴趣的亚群可以个性化流式细胞仪的配置文件，后者可以完成，PArticularly点图。举例来说，到现在为止，我们已经能够排序豚鼠meiocytes我9的不同阶段，但不要歧视和排序亚群内2C人口根本染色的DNA。排序细胞提供良好的高质量的RNA，使下游基因差异表达分析（ 图5）。 协议的描述中可以看出，这是很简单的，可容易地复制，并且不需要特别熟练的人员。我们认为，它可以为各种各样的应用，涉及流式细胞仪或不通过。前者的范围从简单的内容分析睾丸生精提前的快速检查，给别人用制备的目的，如流净化出于不可告人的分子生物学研究特定的细胞群，如下图所示。

<table border="1">
<tbody>
 <tr>
 <td>Name of Reagent/Material</td>
 <td>Company</td>
 <td>Catalogue Number</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>Medimachine system</td>
 <td>BD</td>
 <td>340587</td>
 <td></td>
 </tr>
 <tr>
 <td>Medicon unit (50 &mu;m)</td>
 <td>BD</td>
 <td>340591</td>
 <td></td>
 </tr>
 <tr>
 <td>Filcon unit (50 &mu;m)</td>
 <td>BD</td>
 <td>340603</td>
 <td></td>
 </tr>
 <tr>
 <td>DMEM</td>
 <td>Gibco</td>
 <td>430-2100</td>
 <td></td>
 </tr>
 <tr>
 <td>Fetal calf serum</td>
 <td>PAA</td>
 <td>A11-151</td>
 <td></td>
 </tr>
 <tr>
 <td>NDA</td>
 <td>Chemos BmbH</td>
 <td>277081</td>
 <td></td>
 </tr>
 <tr>
 <td>Hoechst 33342</td>
 <td>Sigma-Aldrich</td>
 <td>14533</td>
 <td>Stock solution 5 mg/ml; used at a final concentration of 5 &mu;g/ml</td>
 </tr>
 <tr>
 <td>Propidium iodide</td>
 <td>Sigma-Aldrich</td>
 <td>287075</td>
 <td>Stock solution 1 mg/ml; used at a final concentration of 50 &mu;g/ml</td>
 </tr>
 </tbody>
</table>

simple and efficient technique for the preparation of testicular cell suspensions

哺乳动物睾丸是非常复杂的器官，包含超过30种不同类型的细胞，包括体睾丸细胞和生殖细胞的不同阶段。这种异质性是一个重要的缺点，关于哺乳动物精子发生的研究的基础，作为纯的或富集的细胞群，在精子发育的某些阶段需要1分子分析。 各种策略，如Staput离心淘洗1，2,3，和流式细胞仪（FC）4,5，为了使基因差异表达的研究已获得丰富或纯化睾丸细胞群。 它是必需的细胞是在悬浮液中大多数浓缩/净化方法。理想的情况下，将细胞悬浮液，将代表原始组织，具有高比例的活细胞和少数多核 - 这往往会形成，因为合胞性质的生精上皮6,7 -和缺乏细胞团块。以前的报告已经证明，由一个专门的机械方法编制的睾丸细胞悬液成群更容易比胰酶消化1。另一方面，酶的RNA酶处理的和/或分解的酶，如胰蛋白酶和胶原酶导致特定的大分子的降解，这是不希望的目标的下游应用。理想的过程中应尽可能短，涉及最少的操作，从而实现了良好的保存大分子的利益，如基因。目前的协议，从固体组织细胞悬液的制备通常费时，高度取决于运营商，并且可以选择性地破坏某些类型的细胞1,8。 这里介绍的协议结合了高度重复性和极其短暂的机械分解的优势酶处理bsence，导致以良好的品质，可以用于流式细胞仪分析和分选4，不可告人的基因表达研究9的细胞悬浮液。

以及分列的细胞悬浮液从大鼠睾丸制备与这里描述的协议的一个例子是图1中所示。 在酶处理6,8和前面描述的机械分解方法2相比，这里介绍的是速度更快，处理涉及较少，很容易重现（取决于运营商），并呈现稀缺的细胞碎片（特别是相对于其它机械方法）和非常少的多核（已经描述了形成作为广泛的组织操纵1,2的结果）。此外，由于相对于酶处理，它避免了使用RNA酶，胰蛋白酶和胶原酶，可能有利于大分子降解。 另一方面，虽然以前的报告已经证明，由一个专门的机械方法编制的睾丸细胞悬液成群更容易比胰酶消化上课1，应用本发明方法所提供的非常小的聚集的细胞悬浮液中，在图1中可以看出。在这个意义上说，我们已经发现NDA列入非常有效的防止细胞聚集，并避免在随后的流的研究喷嘴堵塞， 图1还表明细胞碎片的稀缺性，这也是明显的，在图2中所示的FC直方图。 此外，用这种方法制备的细胞悬液充分代表不同的睾丸细胞类型。得出的结论进行比较，这里介绍的方法从细胞计数中的生精小管的横截面的数据报的睾丸细胞制备的悬浮液的细胞的组合物，并制备细胞悬浮液，以及使用其他方法（ 表1）。 FC直方图得到悬浮液由预选nt的协议和染色用Hoechst 33342（ 图2A）或PI（ 图2B）基本上没有不同于先前报道的8，也支持该过程不假设任何特定的细胞类型选择性地损坏。 <table border="1" fo:keep-together.within-page="always"><tbody><tr><td> 基于DNA含量的睾丸细胞类型 </td><td> 完好睾丸（％） </td><td> 准备Medimachine -悬浮B（％） </td><td> 胰酶消化悬浮液（％） </td></tr><tr><td></td><td colspan="3"> A） 小家鼠 </td></tr><tr><td> Ç </td><td> 66.2 </td><td> 62.5 </td><td> 79.6 </td></tr><tr><td> 2C </td><td> 16.4 </td><td> 18.4 </td><td> 7.3 </td></tr><tr><td> 4C &lt;/ TD&gt; <td> 17.9 </td><td> 18.7 </td><td> 8.7 </td></tr><tr><td>他人</td><td> - </td><td> - </td><td> 4.6 </td></tr><tr><td></td><td colspan="3"> B） 豚鼠porcellus </td></tr><tr><td> Ç </td><td> 66.5 </td><td> 65.5 </td><td> N / D </td></tr><tr><td> 2C </td><td> 11.0 </td><td> 11.5 </td><td> N / D </td></tr><tr><td> 4C </td><td> 22.5 </td><td> 23.0 </td><td> N / D </td></tr><tr><td colspan="4"> 一个细胞计数，通过显微镜观察评估。 B细胞计数流式细胞仪进行了评估。 </td></tr></tbody></table> 表1中。成人睾丸细胞群，其DNA含量不同的细胞悬液从小鼠和豚鼠（A）（B）准备由兹提出的方法相比，完整的睾丸-鼠标的相对百分比- T准备Ø胰蛋白酶的悬浮液（修改从格伊辛格和罗德里格斯Casuriaga的的，细胞遗传学， 基因组住宅 128，46（2010））。 DNA含量为:C（圆形和长形精子细胞，精子），2C（睾丸细胞，精原细胞，次级精母细胞）和4C（初级精母细胞和精原细胞增殖几个在G2期）。 <img src="/files/ftp_upload/50102/50102fig1.jpg" alt="图1" fo:content-width="4.5in" fo:src="/files/ftp_upload/50102/50102fig1highres.jpg"/> 图1。本协议，并编制相衬显微镜观察成年大鼠睾丸细胞悬液。鉴于部分细胞胞质中可以看出，保存完好。酒吧对应到25微米。转载自罗德里格斯Casuriaga， 等。，生物学。程序，。在线11，184（2009）。 图2。 FC DNA含量分析在所有的情况下成年大鼠，小鼠，豚鼠，以及从后21天产后（DPP）幼鼠，染色的重要染料Hoechst 33342（A）或（B）与PI睾丸细胞悬液。 C，2C和4C的细胞群，可以很容易地与两种染料，以及显然子单倍体峰的左侧的C人口中公开获得的直方图。后者的峰已被证明含有精子，显示为一个单独的，减染色的亚群，由于他们的染色质凝集状态12。注意的稀缺性在所有的图形碎片。 21民进党（少年的标本）的型材，缺乏精子细胞和精子，这一点尤其明显。修改从格伊辛格和罗德里格斯Casuriaga的的， 细胞遗传学。<html>基因128，46（2010）。 <a href="https://www.jove.com/files/ftp_upload/50102/50102fig2large.jpg" target="_blank">点击这里查看大图。</a> <img src="/files/ftp_upload/50102/50102fig3.jpg" alt="图3" fo:content-width="6in" fo:src="/files/ftp_upload/50102/50102fig3highres.jpg"/> 图3。 4C细胞群体排序排序从成年鼠的睾丸细胞悬液。细胞沉积到干净的聚L-赖氨酸处理幻灯片和相衬显微镜下姬姆萨染色后（B）（A）或明场观察。酒吧= 20微米。转载从格伊辛格和罗德里格斯Casuriaga的的， 细胞遗传学。基因 128，46（2010）。 tp_upload/50102/50102fig4highres.jpg"/&gt; 图4 A）FC分析的成年豚鼠睾丸细胞悬浮液与协议描述（一），直方图（b）中 ，积点。请注意，两个亚群B）的分析排序细胞从4C R3（一，二）和R4（如a，b&#39;）的区域（A，A&#39;），落射荧光显微镜图像的PI染色的细胞在图4C的细胞群。 。需要注意的是原子核从R3区域相对较小。酒吧:10微米（B，B&#39;），激光共聚焦显微镜使用的抗体SYCP3蔓延细胞的免疫细胞化学反应（联会复合体[SC]蛋白3，横向元素成分）。图片允许R3分数对应的结论是早期（lepto /偶线），可以看到简单的轴和短绵延的SCS meiocytes，而R4包含粗线期meiocytes，与COM完全组装的SCS。修改罗德里格斯Casuriaga 等，流式细胞仪 79，625（2011）。 <a href="https://www.jove.com/files/ftp_upload/50102/50102fig4large.jpg" target="_blank">点击这里查看大图。</a> <img src="/files/ftp_upload/50102/50102fig5.jpg" alt="图5" /> 图5。 A）从生精流的排序条件的细胞部分2C，R3和R4（后两个级分的解释是在图4中）中提取的总RNA的琼脂糖凝胶电泳，制备细胞悬浮液B）的放射自显影的变性与这里描述的协议。聚丙烯酰胺凝胶电泳显示出差异表达的cDNA带获​​得通过mRNA差异显示法"（RNAimage GenHunter公司，田纳西州纳什维尔）从试剂盒引物组合之一。基因的细胞群，在从相同的三个<strong&gt; A）进行了比较。所有实验均重复（逆转录和PCR）的制造商的说明进行操作，并运行在相邻车道。星号表示差异表达的cDNA带R3（早期减数分裂细胞）中出现的重复实验（大概对应差异表达基因）。转载自罗德里格斯Casuriaga 等，流式细胞仪A. 79，625（2011）。

Watch this Scientific Journal Video about Simple and Efficient Technique for the Preparation of Testicular Cell Suspensions at JoVE.com

Simple and Efficient Technique for the Preparation of Testicular Cell Suspensions

睾丸细胞悬浮液从啮齿动物材料，避免酶和洗涤剂，机械制备一种新的协议进行说明。方法很简单，速度快，重复性好，并呈现良好的品质，这是适合流式分选和RNA提取的细胞悬液。

简单和高效的睾丸细胞悬液的制备技术

Mammalian testes are very complex organs that contain over 30 different cell types, including somatic testicular cells and different stages of germline ...

simple-efficient-technique-for-preparation-testicular-cell

Universidad San Sebastian

Research

JoVE Journal

Biology

18.6K 次观看.  Instituto de Investigaciones Biológicas Clemente Estable (IIBCE). 睾丸细胞悬浮液从啮齿动物材料，避免酶和洗涤剂，机械制备一种新的协议进行说明。方法很简单，速度快，重复性好，并呈现良好的品质，这是适合流式分选和RNA提取的细胞悬液。

视频: Simple and Efficient Technique for the Preparation of Testicular Cell Suspensions

Preparation of Single-Cell Suspensions from Mouse Spleen with the gentleMACS Dissociator

Single-cell suspensions are a prerequisite for experiments in cell separation, cell analysis and cell culture.  To avoid tedious and often painful manual dissociations the gentleMACS Dissociator allows one to dissociate tissue very efficiently under controlled and reproducible conditions.  The gentleMACS Dissociator can optimally dissociate mouse spleen, combining timesaving and standardization with user-safety.

This video describes how to dissociate mouse spleens using the gentleMACS Dissociator, an automated bench-top device that can mechanically disrupt tissues using special tubes to produce viable cell suspensions. Following dissociation, spleens are filtered, centrifuged, and resuspended for further applications.

This video describes a simple, time-saving technique for automated tissue dissociation using the gentleMACS Dissociator to prepare single-cell suspensions of mouse splenocytes.

gentleMACS Dissociator从小鼠脾脏单细胞悬浮液的制备

Single-cell suspensions are a prerequisite for experiments in cell separation, cell analysis and cell culture.  To avoid tedious and often painful manual ...

科研

生物学

Standardized Preparation of Single-Cell Suspensions from Mouse Lung Tissue using the gentleMACS Dissociator

The preparation of single-cell suspensions from tissues is an important prerequisite for many experiments in cellular research. The process of dissociating whole organs requires specific parameters in order to obtain a high number of viable cells in a reproducible manner. The gentleMACS Dissociator optimizes this task with a simple, practical protocol. The instrument contains pre-programmed settings that are optimized for the efficient but gentle dissociation of a variety of tissue types, including mouse lungs. In this publication the use of the gentleMACS Dissociator on lung tissue derived from mice is demonstrated.

Dissociating cells from specific tissue types requires specific parameters for tissue agitation to obtain a high volume of viable, culturable cells. The Miltenyi gentleMACS dissociator optimizes this task with a simple, practical protocol. In this publication the use of this apparatus on lung tissue is explained.

标准化的制备小鼠肺组织单细胞悬浮液使用gentleMACS Dissociator

The preparation of single-cell suspensions from tissues is an important prerequisite for many experiments in cellular research. The process of ...

Preparation of Pooled Human Platelet Lysate (pHPL) as an Efficient Supplement for Animal Serum-Free Human Stem Cell Cultures

Platelet derived growth factors have been shown to stimulate cell proliferation efficiently in vivo1,2 and in vitro. This effect has been reported for mesenchymal stromal cells (MSCs), fibroblasts and endothelial colony-forming cells with platelets activated by thrombin3-5 or lysed by freeze/thaw cycles6-14 before the platelet releasate is added to the cell culture medium. The trophic effect of platelet derived growth factors has already been tested in several trials for tissue engineering and regenerative therapy.1,15-17 Varying efficiency is considered to be at least in part due to individually divergent concentrations of growth factors18,19 and a current lack of standardized protocols for platelet preparation.15,16 This protocol presents a practicable procedure to generate a pool of human platelet lysate (pHPL) derived from routinely produced platelet rich plasma (PRP) of forty to fifty single blood donations. By several freeze/thaw cycles the platelet membranes are damaged and growth factors are efficiently released into the plasma. Finally, the platelet fragments are removed by centrifugation to avoid extensive aggregate formation and deplete potential antigens. The implementation of pHPL into standard culture protocols represents a promising tool for further development of cell therapeutics propagated in an animal protein-free system.

Preparation of Pooled Human Platelet Lysate pHPL as an Efficient Supplement for Animal Serum-Free Human Stem Cell Cultures

Human platelet lysate is a rich source of growth factors and a potent supplement in cell culture. This protocol presents the process of preparing a large pool of human platelet lysate by starting from platelet rich plasma, performing several freeze-thaw cycles and depleting the platelet fragments.

汇集人类血小板裂解液作为一种有效的补充（pHPL）的动物血清自由人干细胞培养制备

Platelet derived growth factors have been shown to stimulate cell proliferation efficiently in vivo1,2 and in vitro. This effect has been reported for ...

Preparation of embryos for Electron Microscopy of the Drosophila embryonic heart tube

The morphogenesis of the Drosophila embryonic heart tube has emerged as a valuable model system for studying cell migration, cell-cell adhesion and cell shape changes during embryonic development. One of the challenges faced in studying this structure is that the lumen of the heart tube, as well as the membrane features that are crucial to heart tube formation, are difficult to visualize in whole mount embryos, due to the small size of the heart tube and intra-lumenal space relative to the embryo. The use of transmission electron microscopy allows for higher magnification of these structures and gives the advantage of examining the embryos in cross section, which easily reveals the size and shape of the lumen. In this video, we detail the process for reliable fixation, embedding, and sectioning of late stage Drosophila embryos in order to visualize the heart tube lumen as well as important cellular structures including cell-cell junctions and the basement membrane.

Preparation of embryos for Electron Microscopy of the Drosophila embryonic heart tube

We describe a process for fixation, embedding, sectioning, and imaging of late stage Drosophila embryos for Trasmission Electron Microscopy of the embryonic heart tube. This technique allows for the visualization of the heart tube lumen as well as the basement membrane, which lines the lumen of the heart.

电子显微镜对胚胎的制备果蝇胚胎心管

The morphogenesis of the Drosophila  embryonic heart tube has emerged as a valuable model system for studying cell migration, cell-cell adhesion and cell ...

Preparation of Drosophila S2 cells for Light Microscopy

The ideal experimental system would be cheap and easy to maintain, amenable to a variety of techniques, and would be supported by an extensive literature and genome sequence database. Cultured Drosophila S2 cells, the product of disassociated 20-24 hour old embryos1, possess all these properties. Consequently, S2 cells are extremely well-suited for the analysis of cellular processes, including the discovery of the genes encoding the molecular components of the process or mechanism of interest. The features of S2 cells that are most responsible for their utility are the ease with which they are maintained, their exquisite sensitivity to double-stranded (ds)RNA-mediated interference (RNAi), and their tractability to fluorescence microscopy as either live or fixed cells.
S2 cells can be grown in a variety of media, including a number of inexpensive, commercially-available, fully-defined, serum-free media2. In addition, they grow optimally and quickly at 21-24&deg;C and can be cultured in a variety of containers. Unlike mammalian cells, S2 cells do not require a regulated atmosphere, but instead do well with normal air and can even be maintained in sealed flasks.
Complementing the ease of RNAi in S2 cells is the ability to readily analyze experimentally-induced phenotypes by phase or fluorescence microscopy of fixed or live cells. S2 cells grow in culture as a single monolayer but do not display contact inhibition. Instead, cells tend to grow in colonies in dense cultures. At low density, S2 cultures grown on glass or tissue culture-treated plastic are round and loosely-attached. However, the cytology of S2 cells can be greatly improved by inducing them to flatten extensively by briefly culturing them on a surface coated with the lectin, concanavalin A (ConA)3. S2 cells can also be stably transfected with fluorescently-tagged markers to label structures or organelles of interest in live or fixed cells. Therefore, the usual scenario for the microscopic analysis of cells is this: first, S2 cells (which can possess transgenes to express tagged markers) are treated by RNAi to eliminate a target protein(s). RNAi treatment time can be adjusted to allow for differences in protein turn-over kinetics and to minimize cell trauma/death if the target protein is important for viability. Next, the treated cells are transferred to a dish containing a coverslip pre-coated with conA to induce cells to spread and tightly adhere to the glass. Finally, cells are imaged with the researcher's choice of microscopy modes. S2 cells are particularly good for studies requiring extended visualization of live cells since these cells stay healthy at room temperature and normal atmosphere.

Preparation of Drosophila S2 cells for Light Microscopy

Drosophila Schneider (S2) cells are an increasingly popular system for the discovery and functional analysis of genes. Our goal is to describe some of the microscopic techniques that make S2 cells such an increasingly important experimental system.

制备果蝇 S2细胞，光学显微镜

The ideal experimental system would be cheap and easy to maintain, amenable to a variety of techniques, and would be supported by an extensive literature ...

Preparation of Quality Inositol Pyrophosphates

Myo-inositol is present in nature either unmodified or in more complex phosphorylated derivates. Of the latest, the two most abundant in eukaryotic cells are inositol pentakisphosphate (IP5) and inositol hexakisphosphate (phytic acid or IP6). IP5 and IP6 are the precursors of inositol pyrophosphate molecules that contain one or more pyrophosphate bonds1. Phosphorylation of IP6 generates diphoshoinositolpentakisphosphate (IP7 or PP-IP5) and bisdiphoshoinositoltetrakisphosphate (IP8 or (PP)2-IP4). Inositol pyrophosphates have been isolated from all eukaryotic organisms so far studied. In addition, the two distinct classes of enzymes responsible for inositol pyrophosphate synthesis are highly conserved throughout evolution2-4.
The IP6 kinases (IP6Ks) posses an enormous catalytic flexibility, converting IP5 and IP6 to PP-IP4 and IP7 respectively and subsequently, by using these products as substrates, promote the generation of more complex molecules5,6. Recently, a second class of pyrophosphate generating enzymes was identified in the form of the yeast protein VIP1 (also referred as PP-IP5K), which is able to convert IP6 to IP7 and IP87,8.
Inositol pyrophosphates regulate many disparate cellular processes such as insulin secretion9, telomere length10,11, chemotaxis12, vesicular trafficking13, phosphate homeostasis14 and HIV-1 gag release15. Two mechanisms of actions have been proposed for this class of molecules. They can affect cellular function by allosterically interacting with specific proteins like AKT16. Alternatively, the pyrophosphate group can donate a phosphate to pre-phosphorylated proteins17. The enormous potential of this research field is hampered by the absence of a commercial source of inositol pyrophosphates, which is preventing many scientists from studying these molecules and this new post-translational modification. The methods currently available to isolate inositol pyrophosphates require sophisticated chromatographic apparatus18,19. These procedures use acidic conditions that might lead to inositol pyrophosphate degradation20 and thus to poor recovery. Furthermore, the cumbersome post-column desalting procedures restrict their use to specialized laboratories.
In this study we describe an undemanding method for the generation, isolation and purification of the products of the IP6-kinase and PP-IP5-kinases reactions. This method was possible by the ability of polyacrylamide gel electrophoresis (PAGE) to resolve highly phosphorylated inositol polyphosphates20. Following IP6K1 and PP-IP5K enzymatic reactions using IP6 as the substrate, PAGE was used to separate the generated inositol pyrophosphates that were subsequently eluted in water.

Inositol pyrophosphates play an important role in human pathologies such cancer, diabetes and obesity; however, the exact mechanism of action is a matter of dispute. The lack of commercially available inositol pyrophosphates renders detailed studies problematic. Here we describe a simple protocol to produce and isolate milligrams of inositol pyrophosphates.

编制质量肌醇Pyrophosphates

Myo-inositol is present in nature either unmodified or in more complex phosphorylated derivates. Of the latest, the two most abundant in eukaryotic cells ...

Measurement of Vacuolar and Cytosolic pH In Vivo in Yeast Cell Suspensions

Vacuolar and cytosolic pH are highly regulated in yeast cells and occupy a central role in overall pH homeostasis. We describe protocols for ratiometric measurement of pH in vivo using pH-sensitive fluorophores localized to the vacuole or cytosol. Vacuolar pH is measured using BCECF, which localizes to the vacuole in yeast when introduced into cells in its acetoxymethyl ester form. Cytosolic pH is measured with a pH-sensitive GFP expressed under control of a yeast promoter, yeast pHluorin. Methods for measurement of fluorescence ratios in yeast cell suspensions in a fluorimeter are described. Through these protocols, single time point measurements of pH under different conditions or in different yeast mutants have been compared and changes in pH over time have been monitored. These methods have also been adapted to a fluorescence plate reader format for high-throughput experiments. Advantages of ratiometric pH measurements over other approaches currently in use, potential experimental problems and solutions, and prospects for future use of these techniques are also described.

Measurement of Vacuolar and Cytosolic pH In Vivo in Yeast Cell Suspensions

Vacuolar and cytosolic pH can be measured in live yeast (S. cerevisiae) cells using ratiometric fluorescent dyes localized to specific cellular compartments. We describe procedures for measuring vacuolar pH with BCECF-AM, which localizes to the vacuole in yeast, and cytosolic pH with a cytosolic ratiometric pH-sensitive GFP (yeast pHluorin).

液泡和胞质pH值的测量<em&gt;在体内</em在酵母细胞悬浮液

Vacuolar and  cytosolic pH are highly regulated in yeast cells and occupy a central role in  overall pH homeostasis. We describe  protocols for ...

Efficient Agroinfiltration of Plants for High-level Transient Expression of Recombinant Proteins

Mammalian cell culture is the major platform for commercial production of human vaccines and therapeutic proteins. However, it cannot meet the increasing worldwide demand for pharmaceuticals due to its limited scalability and high cost. Plants have shown to be one of the most promising alternative pharmaceutical production platforms that are robust, scalable, low-cost and safe. The recent development of virus-based vectors has allowed rapid and high-level transient expression of recombinant proteins in plants. To further optimize the utility of the transient expression system, we demonstrate a simple, efficient and scalable methodology to introduce target-gene containing Agrobacterium into plant tissue in this study. Our results indicate that agroinfiltration with both syringe and vacuum methods have resulted in the efficient introduction of Agrobacterium into leaves and robust production of two fluorescent proteins; GFP and DsRed. Furthermore, we demonstrate the unique advantages offered by both methods. Syringe infiltration is simple and does not need expensive equipment. It also allows the flexibility to either infiltrate the entire leave with one target gene, or to introduce genes of multiple targets on one leaf. Thus, it can be used for laboratory scale expression of recombinant proteins as well as for comparing different proteins or vectors for yield or expression kinetics. The simplicity of syringe infiltration also suggests its utility in high school and college education for the subject of biotechnology. In contrast, vacuum infiltration is more robust and can be scaled-up for commercial manufacture of pharmaceutical proteins. It also offers the advantage of being able to agroinfiltrate plant species that are not amenable for syringe infiltration such as lettuce and Arabidopsis. Overall, the combination of syringe and vacuum agroinfiltration provides researchers and educators a simple, efficient, and robust methodology for transient protein expression. It will greatly facilitate the development of pharmaceutical proteins and promote science education.

Plants offer a novel system for the production of pharmaceutical proteins on a commercial scale that is more scalable, cost-efficient and safe than current expression paradigms. In this study, we report a simple and convenient, yet scalable approach to introduce target-gene containing Agrobacterium tumefaciens into plants for protein transient expression.

高级别瞬态表达重组蛋白的植物高效的农杆菌

Mammalian cell culture is the major platform for commercial production of human vaccines and therapeutic proteins. However, it cannot meet the increasing ...

Efficient iPS Cell Generation from Blood Using Episomes and HDAC Inhibitors

This manuscript illustrates a protocol for efficiently creating integration-free human induced pluripotent stem cells (iPSCs) from peripheral blood using episomal plasmids and histone deacetylase (HDAC) inhibitors. The advantages of this approach include: (1) the use of a minimal amount of peripheral blood as a source material; (2) nonintegrating reprogramming vectors; (3) a cost effective method for generating vector free iPSCs; (4) a single transfection; and (5) the use of small molecules to facilitate epigenetic reprogramming. Briefly, peripheral blood mononuclear cells (PBMCs) are isolated from routine phlebotomy samples and then cultured in defined growth factors to yield a highly proliferative erythrocyte progenitor cell population that is remarkably amenable to reprogramming. Nonintegrating, nontransmissible episomal plasmids expressing OCT4, SOX2, KLF4, MYCL, LIN28A, and a p53 short hairpin (sh)RNA are introduced into the derived erythroblasts via a single nucleofection. Cotransfection of an episome that expresses enhanced green fluorescent protein (eGFP) allows for easy identification of transfected cells. A separate replication-deficient plasmid expressing Epstein-Barr nuclear antigen 1 (EBNA1) is also added to the reaction mixture for increased expression of episomal proteins. Transfected cells are then plated onto a layer of irradiated mouse embryonic fibroblasts (iMEFs) for continued reprogramming. As soon as iPSC-like colonies appear at about twelve days after nucleofection, HDAC inhibitors are added to the medium to facilitate epigenetic remodeling. We have found that the inclusion of HDAC inhibitors routinely increases the generation of fully reprogrammed iPSC colonies by 2 fold. Once iPSC colonies exhibit typical human embryonic stem cell (hESC) morphology, they are gently transferred to individual iMEF-coated tissue culture plates for continued growth and expansion.

Here we describe a protocol for generating human induced pluripotent stem cells from peripheral blood using an episome based reprogramming strategy and histone deacetylase inhibitors.

从血液高效的iPS细胞生成使用附加体和HDAC抑制剂

This manuscript illustrates a protocol for efficiently creating integration-free human induced pluripotent stem cells (iPSCs) from peripheral blood using ...

Efficient Mammalian Cell Expression and Single-step Purification of Extracellular Glycoproteins for Crystallization

Production of secreted mammalian proteins for structural and biophysical studies can be challenging, time intensive, and costly. Here described is a time and cost efficient protocol for secreted protein expression in mammalian cells and one step purification using nickel affinity chromatography. The system is based on large scale transient transfection of mammalian cells in suspension, which greatly decreases the time to produce protein, as it eliminates steps, such as developing expression viruses or generating stable expressing cell lines. This protocol utilizes cheap transfection agents, which can be easily made by simple chemical modification, or moderately priced transfection agents, which increase yield through increased transfection efficiency and decreased cytotoxicity. Careful monitoring and maintaining of media glucose levels increases protein yield. Controlling the maturation of native glycans at the expression step increases the final yield of properly folded and functional mammalian proteins, which are ideal properties to pursue X-ray crystallography. In some cases, single step purification produces protein of sufficient purity for crystallization, which is demonstrated here as an example case.

This is a quick, cost-efficient protocol for the production of secreted, glycosylated mammalian proteins and subsequent single-step purification with sufficient yields of homogenous protein for X-ray crystallography and other biophysical studies.

高效的哺乳动物细胞表达和细胞外糖蛋白的结晶一步纯化

Production of secreted mammalian proteins for structural and biophysical studies can be challenging, time intensive, and costly. Here described is a time ...