Name: an in vitro 3d model and computational pipeline to quantify the vasculogenic potential of ipsc-derived endothelial progenitors
Uploaded: 2019-05-13T13:00:00
Description: Watch this Scientific Journal Video about An In Vitro 3D Model and Computational Pipeline to Quantify the Vasculogenic Potential of iPSC-Derived Endothelial Progenitors at JoVE.com

这项工作得到了美国心脏协会(授予J.Z.的15SDG25740035号)、美国国家卫生研究院国家生物医学成像和生物工程研究所(NIBIB)的支持(授予C.C.的赠款号EB007507),以及再生康复研究与培训联盟(AR3T,授予编号1 P2C HD086843-01,授予J.Z.)。我们要感谢Jeanne Stachowiak教授(德克萨斯大学奥斯汀分校)就共聚焦显微镜提供的技术建议。我们还感谢与塞缪尔·米赫利奇(德克萨斯大学奥斯汀分校)、艾丽西亚·艾伦博士(德克萨斯大学奥斯汀分校)、朱莉·雷特莱夫斯基博士(适应性生物技术)和莱昂·贝兰博士(范德比尔特大学)的讨论,以表达他们对三维网络的计算分析。最后,我们感谢鲍小平博士(加州大学伯克利分校)关于将iPSC区分为iPSC-EP的建议。

1. 培养介质和涂层解决方案的准备
<ol><li>要制备体外内丁涂层溶液,在Dulbecco的磷酸盐缓冲盐水(DPBS)中稀释体外奈丁1:100。 注意:一旦稀释,不建议存储此解决方案供将来使用。</li>
	<li>从制造商处收到无苯酚红、生长因子减少的胶状蛋白混合物(见材料表)后,在4°C的冰上解冻,直到混合物透明且流畅。将混合物放在冰上,放在层流罩中,将混合物75 μL移液器放入1.8 mL微离心管中,并立即在-20...

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该协议涉及三种细胞培养基基中细胞的长期培养:E8、LaSR巴塞尔和EGM-2。因此,应非常小心,适当地消毒所有材料。此外,在实验室的层流罩中工作时,应始终佩戴实验室外套和乙醇清洁手套。建议经常检测支原体污染;如果在 iPSC 培养期间观察到大量碎屑或观察到分化效率突然下降,则支原体污染是可能的原因。使用该协议生成的 iPSC-EP 往往会沉积大量的 ECM,从而延长分离时间,并导致单个细胞悬浮液分离?...

人类脐带静脉内皮细胞(HUVECs)和其他原发内皮细胞类型已经使用了20年,以模型血管发芽和在体外发育1。这种血管平台有望阐明心血管疾病的分子和组织级机制,并可能为原始血管网络2、3的发展提供生理见解。尽管血管建模领域取得了显著进展,但能够定量建模和评估生理血管发育的"金本位"测定仍然遥遥无期。大多数已公布的协议没有充分重述血管利基,以鼓励成熟、功能性血管的形成,或者没有方法在三维上定量比较评估细胞类型的血管生成电位(3D)。
许多目前的血管模型是有限的,他们的能力,模仿生理血管利基。最常用的体外平台之一是胶状蛋白混合物的管形成测定。简单地说,HUVECs被播种为单细胞,在薄薄的凝胶层上,由从肉瘤细胞外基质(ECM)中采集的蛋白质组成;在一至两天内,HUVECs自组装成原始管4。然而,这个过程发生在双维(2D)和内皮细胞(ECs)用于这个测定不形成封闭的,空心流明,从而限制了这些研究的生理意义。最近,EC和支持细胞(例如,中生干细胞(MSCs)和围细胞)在模拟原生ECM纤维结构的3D微环境中共同培养,如胶原蛋白或纤维蛋白水凝胶5。为了模拟这种微环境下的血管发育,通常采用涂有EC的聚合物珠子。加入其他细胞分泌的外源生长因子和/或生长因子,这些细胞间质嵌入在水凝胶中,可以诱导ECs,涂覆聚合物珠子,发芽并形成单流明;然后可以计算芽和容器的数量和直径。然而,这些芽是奇异的,不形成一个封闭的,连接的网络,如在生理条件下看到,因此更让人想起肿瘤血管模型。微流体装置也被用来模拟血管利基,并促进在EC载水凝胶7,8的血管的形成。通常,血管生成生长因子梯度应用于循环细胞培养基,以诱导EC迁移和发芽。构成发达容器流明的ECs对通过微流体装置的流体流动引起的剪切应力敏感;因此,这些微流体装置捕获静态模型中不可访问的关键生理参数。但是,这些设备需要昂贵的微制造能力。
最重要的是,所有三种血管模型(2D、3D、微流体)绝大多数使用初级EC以及主要支持细胞类型。原发性细胞不能发展成有效的心血管治疗,因为细胞在植入后会产生免疫反应;此外,HUVEC 和类似的原发性细胞类型不是患者特异性的,并且不会捕获遗传倾向或预先存在的健康状况(如糖尿病)患者发生的血管异常。诱导多能干细胞(iPSCs)在过去十年中已经作为一种患者特异性增殖细胞源出现,可以分化成人体中的所有体细胞9。特别是,已经发布了协议,概述了iPSC衍生的内皮祖子(iPSC-EP)10、11的生成和隔离。iPSC-EP 是双能的,因此可以进一步分化为内皮细胞和平滑肌细胞/细胞,成熟、功能性血管的构建基块。只有一项研究令人信服地详细说明了iPSC-EP在3D微环境中的初级毛细管丛的发育12;尽管本研究对于了解iPSC-EP总成和天然和合成水凝胶的分化至关重要,但它没有定量地比较所产生血管的网络拓扑。另一项最近的研究使用聚合物珠模型比较了HUVECs和iPSC衍生的EC5的发芽。因此,显然需要进一步阐明调节iPSC-EP血管生成的物理和化学信号机制,并确定这些细胞是否适合缺血治疗和心血管疾病建 模。
在过去十年中,开发了不同的开源计算管道和骨架化算法,以量化和比较血管网络长度和连接性。例如,Charwat等人开发了一种基于Photoshop的管道,从纤维蛋白基质13、14中脂肪衍生干细胞和生长EC的共同培养中提取出一个过滤的、双光化的血管网络图像。也许最广泛使用的拓扑比较工具是AngioTool,一个由国家癌症研究所15在线发布的程序;尽管该计划被广泛采用和充分记录保真度,该计划仅限于分析两维的容器状结构和其他程序,包括AngioSys和Wimasis,共享相同的维数限制16。开发了强大的软件套件,如 Imaris、Lucis 和变形,以分析工程微血管的网络拓扑;但是,对于大多数学术实验室来说,这些套件成本高昂,并且限制了对源代码的访问,这可能会妨碍最终用户根据特定应用程序自定义算法的能力。3D切片机,一个开源磁共振成像/计算机断层扫描包,包含一个血管建模工具包,可以有效地分析3D血管网络的拓扑17;但是,分析依赖于用户手动放置网络的端点,这在分析大型数据集时可能会变得单调乏味,并且可能受用户潜意识偏见的影响。在本手稿中,详细介绍了一个可量化 3D 血管网络的计算管道。为了克服上述限制,此开源计算管道利用 ImageJ 预处理获取的共聚焦图像,将 3D 卷加载到骨架分析器中。骨架分析仪采用平行中轴变薄算法,最初由Kerschnitzki等人开发,用于分析骨细胞网络18的长度和连通性;该算法可有效地描述工程微血管的长度和连通性。
总之,该协议概述了在3D微环境中微血管网络的创建,并提供了一个开源和用户偏差自由计算管道,以随时比较iPSC-EP的血管电位。

<table>
	<tbody>
		<tr>
			<td>&#181;-Slide Angiogenesis</td>
			<td>Ibidi</td>
			<td>N/A</td>
			<td>A flat, glass bottom tissue-culture plate with side walls enables facile confocal imaging</td>
		</tr>
		<tr>
			<td>96 well, round bottom, ultra low attachment microplate, sterile</td>
			<td>Corning</td>
			<td>7007</td>
			<td>Prevents the binding of cell-laden collagen hydrogels to the cell culture dish</td>
		</tr>
		<tr>
			<td>Accutase</td>
			<td>STEMCELL Technologies</td>
			<td>7920</td>
			<td>Gentle cell detachment solution; does not degrade extracellular epitopes vital for FACS</td>
		</tr>
		<tr>
			<td>Advanced DMEM/F12</td>
			<td>Thermo Scientific</td>
			<td>12634010</td>
			<td>The base media for iPSC-EP differentiation.&#160;</td>
		</tr>
		<tr>
			<td>Barnstead GenPure xCAD Plus&#160;</td>
			<td>Thermo Fisher Scientific</td>
			<td>50136165</td>
			<td>Water purification system; others can be readily substituted</td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin solution,7.5% in DPBS, sterile-filtered, BioXtra, suitable for cell culture</td>
			<td>Fisher Scientific</td>
			<td>A8412</td>
			<td>To preserve cell viability when FACs sorting</td>
		</tr>
		<tr>
			<td>CD34-PE, human (clone: AC136)</td>
			<td>Miltenyi Biotec</td>
			<td>130-098-140</td>
			<td>Antibody used for FACs isolation of iPSC-EPs</td>
		</tr>
		<tr>
			<td>CHIR99021</td>
			<td>LC Laboratories</td>
			<td>C-6556</td>
			<td>Induces the formation of mesoderm from pluripotent stem cells</td>
		</tr>
		<tr>
			<td>Collagen I Rat Tail High Protein 100 mg</td>
			<td>VWR</td>
			<td>354249</td>
			<td>Main component of the 3D microenvironment</td>
		</tr>
		<tr>
			<td>Conical centrifuge tubes (15/50 mL)</td>
			<td>Fisher Scientific</td>
			<td>14-959-49D/A</td>
			<td>Used to store and mix relatively large volumes of reagents and cell culture media</td>
		</tr>
		<tr>
			<td>DAPI (4&#39;,6-Diamidino-2-Phenylindole, Dihydrochloride)</td>
			<td>Thermo Fisher Scientific</td>
			<td>D1306</td>
			<td>To counterstain and visualize cell nuclei</td>
		</tr>
		<tr>
			<td>DMEM/F12</td>
			<td>Thermo Fisher Scientific</td>
			<td>11320-082</td>
			<td>For dilution of Matrigel and thawing of pluripotent stem cells</td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s phosphate-buffered saline (DPBS)</td>
			<td>ThermoFisher</td>
			<td>14190-250</td>
			<td>To wash monolayer cultures</td>
		</tr>
		<tr>
			<td>EDTA</td>
			<td>Sigma-Aldrich</td>
			<td>E8008</td>
			<td>For passaging of pluripotent stem cell colonies and to prevent cell aggregation when FACs sorting</td>
		</tr>
		<tr>
			<td>Endothelial Cell Growth Medium 2</td>
			<td>PromoCell</td>
			<td>C-22011</td>
			<td>Promotes endothelial cell viability and proliferation</td>
		</tr>
		<tr>
			<td>Essential 8 Medium</td>
			<td>Thermo Fisher Scientific</td>
			<td>A1517001&#160;&#160;</td>
			<td>For maintenance of pluripotent stem cells</td>
		</tr>
		<tr>
			<td>Glycine,BioUltra, for molecular biology, &#62;=99.0% (NT)</td>
			<td>Sigma-Aldrich</td>
			<td>50046</td>
			<td>Neutralizes remaining detergent</td>
		</tr>
		<tr>
			<td>L-Ascorbic acid 2-phosphate sesquimagnesium salt hydrate,&#62;=95%</td>
			<td>Sigma-Aldrich</td>
			<td>A8960</td>
			<td>Component of iPSC-EP differentiation medium</td>
		</tr>
		<tr>
			<td>MATLAB</td>
			<td>MathWorks</td>
			<td>1.8.0_152</td>
			<td>Multi-paradigm numerical computing environment (free available at most academic institutions)</td>
		</tr>
		<tr>
			<td>Matrigel Matrix GFR PhenolRF Mouse 10 mL (gelatinous protein mixture)</td>
			<td>Fisher Scientific</td>
			<td>356231</td>
			<td>Diluted in DMEM/F12 to coat plates for iPSC-EP differentiation</td>
		</tr>
		<tr>
			<td>Medium-199 10X</td>
			<td>Thermo Fisher Scientific</td>
			<td>1825015</td>
			<td>Used to balance final hydrogel osmolarity and pH</td>
		</tr>
		<tr>
			<td>Microcentrifuge tubes (1.7 mL)</td>
			<td>VWR</td>
			<td>87003-294</td>
			<td>Stores small volumes of reagents</td>
		</tr>
		<tr>
			<td>Phosphate-buffered saline (PBS)</td>
			<td>Sigma-Aldrich</td>
			<td>P3813</td>
			<td>The main ingredient of the immunostaining solutions</td>
		</tr>
		<tr>
			<td>Penicillin-Streptomycin (10,000 U/mL)</td>
			<td>Thermo Fisher Scientific</td>
			<td>15140122</td>
			<td>Antibiotic used after sorting to remove possible contamination from FACS instrument</td>
		</tr>
		<tr>
			<td>Recombinant Human VEGF 165 Protein</td>
			<td>R&#38;D Systems</td>
			<td>293-VE</td>
			<td>Mitogen that stimulates endothelial cell proliferation and tubulogenesis</td>
		</tr>
		<tr>
			<td>Rhodamine phalloidin</td>
			<td>Themo Fisher Scientific</td>
			<td>R415</td>
			<td>To identify F-actin deposition and therfore outline the borders of the vascular networks</td>
		</tr>
		<tr>
			<td>Triton X-100 (nonionic surfactant)</td>
			<td>Sigma-Aldrich</td>
			<td>X-100</td>
			<td>Detergent used to gently permeabilize cells</td>
		</tr>
		<tr>
			<td>Tween-20 (emulsifying reagent)</td>
			<td>Fisher Scientific</td>
			<td>BP337</td>
			<td>Increases the binding specificity of the added antibodies</td>
		</tr>
		<tr>
			<td>VE-Cadherin (F-8)</td>
			<td>Santa Cruz Biotechnology</td>
			<td>sc-9989&#160;</td>
			<td>To identify 3D endothelial lumen in collagen hydrogels</td>
		</tr>
		<tr>
			<td>Vitronectin</td>
			<td>ThermoFisher</td>
			<td>A14700</td>
			<td>For maintenance of pluripotent stem cells</td>
		</tr>
		<tr>
			<td>Y-27632</td>
			<td>Selleck Chemicals</td>
			<td>S1049</td>
			<td>Preserves pluripotent stem cell and iPSC-EP viability when dissociated and re-seeded</td>
		</tr>
	</tbody>
</table>

an in vitro 3d model and computational pipeline to quantify the vasculogenic potential of ipsc-derived endothelial progenitors

诱导多能干细胞(iPSCs)是一种患者特异性增殖细胞源,可分化成任何体细胞类型。双能内皮祖细胞(EP),可以分化成组装成熟、功能性血管所必需的细胞类型,从胚胎和诱导多能干细胞中提取。然而,这些细胞在三维环境中尚未得到严格评估,其血管生成潜力的定量测量仍然难以实现。在这里,首先概述了通过荧光激活细胞分类生成和分离 iPSC-EP,然后介绍了 iPSC-EP 在胶原蛋白水凝胶中的封装和培养。这种细胞外基质(ECM)模拟微环境鼓励强健的血管反应;血管网络形成后一个星期的文化。使用开源软件量化此血管反应的计算管道的创建进行了划定。此管道专为保留毛细管丛的 3D 体系结构而设计,以以最少的用户输入可靠地识别分支数、分支点和总网络长度。

分化(图1),FACS和iPSC-EP封装在胶原蛋白水凝胶中,细胞通常会保持四舍五入24小时,然后开始迁移并形成初始流明。经过大约6天的培养后,当用明场显微镜观察时,水凝胶中可以看到一个原始的毛细管丛(图2)。在共聚焦显微镜(电影1,补充电影1)上成像固定、染色的含细胞水凝胶后,预先处理的图像将转换为骨架,从而能够分析...

Watch this Scientific Journal Video about An In Vitro 3D Model and Computational Pipeline to Quantify the Vasculogenic Potential of iPSC-Derived Endothelial Progenitors at JoVE.com

An In Vitro 3D Model and Computational Pipeline to Quantify the Vasculogenic Potential of iPSC-Derived Endothelial Progenitors

来自诱导多能干细胞(iPSC-EP)的内皮祖子有可能彻底改变心血管疾病的治疗,并能够创建更忠实的心血管疾病模型。本文介绍了iPSC-EP在三维(3D)胶原蛋白微环境中的封装,并对这些细胞的血管生成电位进行了定量分析。

用于量化 iPSC 衍生内皮孕激素的血管生成潜力的体外 3D 模型和计算管道

Induced pluripotent stem cells (iPSCs) are a patient-specific, proliferative cell source that can differentiate into any somatic cell type. Bipotent ...

我们的协议使独特的洞察血管生成分子和散装组织水平机制，可能有助于工程功能血管心血管疾病治疗建模。该协议允许创建强大的三维血管网络，用于评估各种平台的血管生成潜力，并提供一个免费的开源计算管道，用于分析最终的网络拓扑。首先，D5D6 分化细胞培养井每井添加 250 微升细胞分离溶液，在 37 摄氏度下 10 分钟。在孵育结束时，使用P1000移液器尖端将细胞分离成单细胞悬浮液。将细胞溶液汇集在单个 15 毫升锥形管中，用于离心。我们悬浮在200微升冰冷分拣缓冲液中的颗粒，并在4摄氏度下用5微升浓缩荧光结合CD34抗体标记细胞10分钟。在孵育结束时，用五升冰冷分拣缓冲液清洗细胞。通过 40 微米浇注滤网将悬浮液过滤到 5 毫升荧光激活细胞分拣或 FACS 管中。在运行样品之前，对荧光计上第四个未标记的细胞的十分之一进行排序，以荧光强度高、不包含任何未标记的细胞作为负对照区。然后对标记的样本进行排序，其中包含基于高CD34表达的诱导多能干细胞的内皮祖细胞。在排序结束时，将内皮祖细胞转移到微离心管进行离心。对于祖细胞的胶原蛋白水凝胶封装，我们悬浮在内皮生长介质2的200微升中，并辅以10微牛奶的 ROCK 抑制剂Y-27632。在冰上1.8英里微离心管中，将细胞加入400微升播种介质。将350微升胶原蛋白混合到细胞悬浮液中。溶液将变成淡黄色。接下来，将1-Muller氢氧化钠的10微升混合到胶原蛋白和细胞溶液中。解决方案现在将变为明亮的粉红色。这种中和胶原蛋白细胞溶液的移液 56 微升到 96 孔超低附着 U 型细胞培养板的单个孔中，在 37 摄氏度下孵育 30 分钟。在孵育结束时，在明亮的田间显微镜下检查孔，检查细胞的分布不均匀。然后添加100微升新鲜准备的内皮生长介质2，辅以 ROCK抑制剂和血管内皮生长因子到每一个井，并返回板到37摄氏度的培养箱。培养一周后，将250微升4%的甲醛加入每块水凝胶48井板的一个井中，然后从水凝胶中去除介质。然后使用细尖的钳子将水凝胶转移到含有甲醛的井中。在室温下10分钟后，用PBS快速清洗水凝胶，并在室温下用250微升0.5%非离子表面活性剂渗透3-D培养物5分钟。在室温下用250微升PBS洗涤水凝胶，每次洗涤300毫升甘氨酸，然后将每个水凝胶浸入250微升的阻尼缓冲液中，在室温下浸泡30分钟。在4摄氏度下用适当的原抗体在阻断缓冲液中稀释，随后在0.5%乳化试剂和Dulbecco的PBS中洗两次。第二次洗涤后，在室温下用适当的二级抗体标记细胞两小时，防止光线，然后用0.5%乳化试剂和Dulbecco的PBS两次清洗3D培养物，如证明。要可视化细胞核，请添加DAPI，在PBS中以1至10000浓度稀释，在室温下孵育两分钟，随后在0.5%乳化试剂和Dulbecco的PBS中进行两次洗涤。然后使用细尖的钳子将每个样品转移到适当的观察容器中。在胶原蛋白水凝胶中分化、分拣和封装后，细胞通常会保持圆周24小时，然后开始迁移并形成初始流明。经过大约六天的培养后，用明亮的磁场显微镜看，在水凝胶中就会看到原始的毛细管丛。在共体显微镜上对固定、染色、细胞载重水凝胶进行成像后，预处理的图像将转换为骨架，从而能够分析网络的整体长度和连通性。在 FACS 之后添加抗生素势在必行，因为对本仪器内部进行消毒很困难，并且在细胞封装后 24 小时取出抗生素。利用这项技术，我们能够确定哪些物理和化学特征的细胞外基质模仿生物材料控制 iPSC 衍生的衍生内皮祖细胞的血管生成潜力。

Research

JoVE Journal

Developmental Biology

Characterization of Thymic Settling Progenitors in the Mouse Embryo Using In Vivo and In Vitro Assays

Characterization of Thymic Settling Progenitors in the Mouse Embryo Using In Vivo and In Vitro Assays

胸腺表征祖定居在小鼠胚胎使用<em&gt;在体内</em&gt;和<em&gt;在体外</em&gt;测定

Characterizing thymic settling progenitors is important to understand the pre-thymic stages of T cell development, essential to devise strategies for T ...

科研

发育生物学

Development of an In Vitro Assay to Evaluate Contractile Function of Mesenchymal Cells that Underwent Epithelial-Mesenchymal Transition

Development of an In Vitro Assay to Evaluate Contractile Function of Mesenchymal Cells that Underwent Epithelial-Mesenchymal Transition

的发展<em&gt;体外</em&gt;检测以确定间充质细胞将经历上皮 - 间质转化的收缩功能

Fibrosis is often involved in the pathogenesis of various chronic progressive diseases such as interstitial pulmonary disease. Pathological hallmark is ...

In Vitro and In Vivo Models to Study Corneal Endothelial-mesenchymal Transition

In Vitro and In Vivo Models to Study Corneal Endothelial-mesenchymal Transition

在体外和体内模型来研究角膜内皮-间充质转换

Corneal endothelial cells (CECs) play a crucial role in maintaining corneal clarity through active pumping. A reduced CEC count may lead to corneal edema ...

Directed Differentiation of Primitive and Definitive Hematopoietic Progenitors from Human Pluripotent Stem Cells

人多能干细胞对原始和最终造血祖细胞定向分化的研究

One of the major goals for regenerative medicine is the generation and maintenance of hematopoietic stem cells (HSCs) derived from human pluripotent stem ...

Generation of iPSC-derived Human Brain Organoids to Model Early Neurodevelopmental Disorders

源自iPSC的人脑组织体的一代新型早期神经发育障碍

The restricted availability of suitable in vitro models that can reliably represent complex human brain development is a significant bottleneck that ...

The Aortic Ring Co-culture Assay: A Convenient Tool to Assess the Angiogenic Potential of Mesenchymal Stromal Cells In Vitro

The Aortic Ring Co-culture Assay: A Convenient Tool to Assess the Angiogenic Potential of Mesenchymal Stromal Cells In Vitro

主动脉环共培养法: 一种方便的工具, 可以评估骨髓间质细胞的血管生成潜能体外

Angiogenesis is a complex, highly regulated process responsible for providing and maintaining adequate tissue perfusion. Insufficient vasculature ...

Corneal Tissue Engineering: An In Vitro Model of the Stromal-nerve Interactions of the Human Cornea

Corneal Tissue Engineering: An In Vitro Model of the Stromal-nerve Interactions of the Human Cornea

角膜组织工程: 人角膜间质神经相互作用的体外模型

Tissue engineering has gained substantial recognition due to the high demand for human cornea replacements with an estimated 10 million people worldwide ...

Incorporating Pericytes into an Endothelial Cell Bead Sprouting Assay

将毛细血管纳入内皮细胞珠发芽试验

Angiogenesis is the growth of new vessels from pre-existing vasculature and is an important component of many biological processes, including ...

Generation of Scaffold-free, Three-dimensional Insulin Expressing Pancreatoids from Mouse Pancreatic Progenitors In Vitro

Generation of Scaffold-free, Three-dimensional Insulin Expressing Pancreatoids from Mouse Pancreatic Progenitors In Vitro

无支架三维胰岛素表达 Pancreatoids 的实验研究体外培养的小鼠胰祖细胞

The pancreas is a complex organ composed of many different cell types that work together to regulate blood glucose homeostasis and digestion. These cell ...

Computational Analysis of the Caenorhabditis elegans Germline to Study the Distribution of Nuclei, Proteins, and the Cytoskeleton

Computational Analysis of the Caenorhabditis elegans Germline to Study the Distribution of Nuclei, Proteins, and the Cytoskeleton

秀丽线虫生殖的计算分析研究细胞核、蛋白质和细胞骨架的分布

The Caenorhabditis elegans (C. elegans) germline is used to study several biologically important processes including stem cell development, apoptosis, and ...