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。 <p class="jove_conten...

<table><tbody><tr><td>Medimachine system</td><td>BD</td><td>340587</td><td></td></tr><tr><td>Medicon unit (50 &amp;mu;m)</td><td>BD</td><td>340591</td><td></td></tr><tr><td>Filcon unit (50 &amp;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>H&amp;#8211;chst 33342</td><td>Sigma-Aldrich</td><td>14533</td><td>Stock solution 5 mg/ml; used at a final concentration of 5 &amp;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 &amp;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?...

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

Research

JoVE Journal

Biology

18.9K 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

A Standardized Approach for Multispecies Purification of Mammalian Male Germ Cells by Mechanical Tissue Dissociation and Flow Cytometry

Fluorescence-activated cell sorting (FACS) has been one of the methods of choice to isolate enriched populations of mammalian testicular germ cells. Currently, it allows the discrimination of up to 9 murine germ cell populations with high yield and purity. This high-resolution in discrimination and purification is possible due to unique changes in chromatin structure and quantity throughout spermatogenesis. These patterns can be captured by flow cytometry of male germ cells stained with fluorescent DNA-binding dyes such as Hoechst-33342 (Hoechst). Herein is a detailed description of a recently developed protocol to isolate mammalian testicular germ cells. Briefly, single cell suspensions are generated from testicular tissue by mechanical dissociation, double stained with Hoechst and propidium iodide (PI) and processed by flow cytometry. A serial gating strategy, including the selection of live cells (PI negative) with different DNA content (Hoechst intensity), is used during FACS sorting to discriminate up to 5 germ cell types. These include, with corresponding average purities (determined by microscopy evaluation): spermatogonia (66%), primary (71%) and secondary (85%) spermatocytes, and spermatids (90%), further separated into round (93%) and elongating (87%) subpopulations. Execution of the entire workflow is straightforward, allows the isolation of 4 cell types simultaneously with the appropriate FACS machine, and can be performed in less than 2 h. As reduced processing time is crucial to preserve the physiology of ex vivo cells, this method is ideal for downstream high-throughput studies of male germ cell biology. Moreover, a standardized protocol for multispecies purification of mammalian germ cells eliminates methodological sources of variables and allows a single set of reagents to be used for different animal models.

This work describes the standardization of a method to obtain purified germ cell populations from testicular tissue of different mammalian species. It is a straightforward protocol that combines mechanical testis dissociation, staining with Hoechst-33342 and propidium iodide, and FACS sorting, with wide applications in comparative studies of male reproductive biology.

通过机械组织分离和流式细胞术对哺乳动物雄性生殖细胞多特异性纯化的标准化方法

Fluorescence-activated cell sorting (FACS) has been one of the methods of choice to isolate enriched populations of mammalian testicular germ cells. ...

科研

发育生物学

Enrichment of Pachytene Spermatocytes and Spermatids from Mouse Testes Using Standard Laboratory Equipment

To characterize each step of spermatogenesis, researchers must separate different subpopulations of germ cells from testes. However, isolating discrete populations is challenging, because the adult testis contains a complex mix of germ cells from all steps of spermatogenesis along with certain populations of somatic cells. Over the past few decades, different techniques such as centrifugal elutriation, fluorescence-activated cell sorting (FACS), and STA-PUT have been successfully applied to the isolation of germ cells. A drawback is that they all require dedicated devices and specialized training. Following principles underlying the STA-PUT method, a simple protocol has been developed for the isolation of pachytene spermatocytes, round spermatids, and elongating spermatids from mouse testes. After preparing a single cell suspension of testicular cells, specific cell populations are enriched by gravity sedimentation through a discontinuous bovine serum albumin (BSA) density gradient. The cell fractions are then manually collected and microscopically analysed. This modified density gradient for round spermatids (MDR) sedimentation protocol can be widely applied, because it requires only standard laboratory equipment. Furthermore, the protocol requires minimal starting materials, reducing its cost and use of laboratory animals.

Presented here is a protocol for enriching pachytene spermatocytes, round spermatids, and elongating spermatids from adult mouse testes using a discontinuous bovine serum albumin density gradient with standard laboratory equipment.

使用标准实验室设备从小鼠测试中浓缩帕西滕苯细胞和精子

To characterize each step of spermatogenesis, researchers must separate different subpopulations of germ cells from testes. However, isolating discrete ...

Isolation of Sertoli Cells and Peritubular Cells from Rat Testes

The testis, and in particular the male gamete, challenges the immune system in a unique way because differentiated sperm first appear at the time of puberty - more than ten years after the establishment of systemic immune tolerance. Spermatogenic cells express a number of proteins that may be seen as non-self by the immune system. The testis must then be able to establish tolerance to these neo-antigens on the one hand but still be able to protect itself from infections and tumor development on the other hand. Therefore the testis is one of a few immune privileged sites in the body that tolerate foreign antigens without evoking a detrimental inflammatory immune response. Sertoli cells play a key role for the maintenance of this immune privileged environment of the testis and also prolong survival of cotransplanted cells in a foreign environment. Therefore primary Sertoli cells are an important tool for studying the immune privilege of the testis that cannot be easily replaced by established cell lines or other cellular models. Here we present a detailed and comprehensive protocol for the isolation of Sertoli cells - and peritubular cells if desired - from rat testes within a single day.

Primary Sertoli cells are required for studying testis-immune privilege, signal transduction during inflammation or infection, and utilization of their immunoprotective properties. Here we describe an enzyme-based protocol for the isolation of highly purified primary Sertoli cells and peritubular cells from rat testes.

从大鼠睾丸支持细胞的分离和管周细胞

The testis, and in particular the male gamete, challenges the immune system in a unique way because differentiated sperm first appear at the time of ...

免疫与感染

Preparation of Drosophila Larval and Pupal Testes for Analysis of Cell Division in Live, Intact Tissue

Experimental analysis of cells dividing in living, intact tissues and organs is essential to our understanding of how cell division integrates with development, tissue homeostasis, and disease processes. Drosophila spermatocytes undergoing meiosis are ideal for this analysis because (1) whole Drosophila testes containing spermatocytes are relatively easy to prepare for microscopy, (2) the spermatocytes&#8217; large size makes them well suited for high resolution imaging, and (3) powerful Drosophila genetic tools can be integrated with in vivo analysis. Here, we present a readily accessible protocol for the preparation of whole testes from Drosophila third instar larvae and early pupae. We describe how to identify meiotic spermatocytes in prepared whole testes and how to image them live by time-lapse microscopy. Protocols for fixation and immunostaining whole testes are also provided. The use of larval testes has several advantages over available protocols that use adult testes for spermatocyte analysis. Most importantly, larval testes are smaller and less crowded with cells than adult testes, and this greatly facilitates high resolution imaging of spermatocytes. To demonstrate these advantages and the applications of the protocols, we present results showing the redistribution of the endoplasmic reticulum with respect to spindle microtubules during cell division in a single spermatocyte imaged by time-lapse confocal microscopy. The protocols can be combined with expression of any number of fluorescently tagged proteins or organelle markers, as well as gene mutations and other genetic tools, making this approach especially powerful for analysis of cell division mechanisms in the physiological context of whole tissues and organs.

Preparation of Drosophila Larval and Pupal Testes for Analysis of Cell Division in Live, Intact Tissue

The goal of this protocol is to analyze cell division in intact tissue by live and fixed cell microscopy using Drosophila meiotic spermatocytes. The protocol demonstrates how to isolate whole, intact testes from Drosophila larvae and early pupae, and how to process and mount them for microscopy.

用于活、完整组织中细胞分部分析的果蝇拉瓦尔和普帕尔睾试验的制备

Experimental analysis of cells dividing in living, intact tissues and organs is essential to our understanding of how cell division integrates with ...

Extra Cellular Matrix-Based and Extra Cellular Matrix-Free Generation of Murine Testicular Organoids

Testicular organoids provide a tool for studying testicular development, spermatogenesis, and endocrinology in vitro. Several methods have been developed in order to create testicular organoids. Many of these methods rely upon extracellular matrix (ECM) to promote de novo tissue assembly, however, there are differences between methods in terms of biomimetic morphology and function of tissues. Moreover, there are few direct comparisons of published methods. Here, a direct comparison is made by studying differences in organoid generation protocols, with provided outcomes. Four archetypal generation methods: (1) 2D ECM-free, (2) 2D ECM, (3) 3D ECM-free, and (4) 3D ECM culture are described. Three primary benchmarks were used to assess the testicular organoid generation. These are cellular self-assembly, inclusion of major cell types (Sertoli, Leydig, germ, and peritubular cells), and appropriately compartmentalized tissue architecture. Of the four environments tested, 2D ECM and 3D ECM-free cultures generated organoids with internal morphologies most similar to native testes, including the de novo compartmentalization of tubular versus interstitial cell types, the development of tubule-like-structures, and an established long-term endocrine function. All methods studied utilized unsorted, primary murine testicular cell suspensions and used commonly accessible culture resources. These testicular organoid generation techniques provide a highly accessible and reproducible toolkit for research initiatives into testicular organogenesis and physiology in vitro.

Here, four methods for generating testicular organoids from primary neonatal murine testicular cells are described i.e., extracellular matrix (ECM) and ECM-free 2D and 3D culture environments. These techniques have multiple research applications and are especially useful for studying testicular development and physiology in vitro.

基于细胞基和细胞外矩阵的Murine睾丸器官生成

Testicular organoids provide a tool for studying testicular development, spermatogenesis, and endocrinology in vitro. Several methods have been developed ...

Isolation of Murine Spermatogenic Cells using a Violet-Excited Cell-Permeable DNA Binding Dye

Isolation of meiotic spermatocytes is essential to investigate molecular mechanisms underlying meiosis and spermatogenesis. Although there are established cell isolation protocols using Hoechst 33342 staining in combination with fluorescence-activated cell sorting, it requires cell sorters equipped with an ultraviolet laser. Here we describe a cell isolation protocol using the DyeCycle Violet (DCV) stain, a low cytotoxicity DNA binding dye structurally similar to Hoechst 33342. DCV can be excited by both ultraviolet and violet lasers, which improves the flexibility of equipment choice, including a cell sorter not equipped with an ultraviolet laser. Using this protocol, one can isolate three live-cell subpopulations in meiotic prophase I, including leptotene/zygotene, pachytene, and diplotene spermatocytes, as well as post-meiotic round spermatids. We also describe a protocol to prepare single-cell suspension from mouse testes. Overall, the procedure requires a short time to complete (4-5 hours depending on the number of needed cells), which facilitates many downstream applications.

Here we present a simple and efficient method to isolate live meiotic and post-meiotic germ cells from adult mouse testes. Using a low-cytotoxicity, violet-excited DNA binding dye and fluorescence-activated cell sorting, one can isolate highly enriched spermatogenic cell populations for many downstream applications.

使用紫罗兰兴奋细胞渗透DNA结合染料分离穆林精子生成细胞

Isolation of meiotic spermatocytes is essential to investigate molecular mechanisms underlying meiosis and spermatogenesis. Although there are established ...

Flow Cytometry Purification of Mouse Meiotic Cells

The heterogeneous nature of cell types in the testis and the absence of meiotic cell culture models have been significant hurdles to the study of the unique differentiation programs that are manifest during meiosis. Two principal methods have been developed to purify, to varying degrees, various meiotic fractions from both adult and immature animals: elutriation or Staput (sedimentation) using BSA and/or percoll gradients. Both of these methods rely on cell size and density to separate meiotic cells1-5. Overall, except for few cell populations6, these protocols fail to yield sufficient purity of the numerous meiotic cell populations that are necessary for detailed molecular analyses. Moreover, with such methods usually one type of meiotic cells can be purified at a given time, which adds an extra level of complexity regarding the reproducibility and homogeneity when comparing meiotic cell samples.
Here, we describe a refined method that allows one to easily visualize, identify, and purify meiotic cells, from germ cells to round spermatids, using FACS combined with Hoechst 33342 staining7,8. This method provides an overall snapshot of the entire meiotic process and allows one to highly purify viable cells from most stage of meiosis. These purified cells can then be analyzed in detail for molecular changes that accompany progression through meiosis, for example changes in gene expression9,10and the dynamics of nucleosome occupancy at hotspots of meiotic recombination11.

An efficient method to obtain highly purified viable meiotic fractions from mouse testis is described, which combines a refined cell dissociation protocol with fluorescent activated cell sorting (FACS). This method takes advantage of differences in the DNA content and nuclear density of discrete meiotic fractions.

流动小鼠减数分裂细胞的流式细胞仪净化

The heterogeneous nature of cell types in the testis and the absence of meiotic cell culture models have been significant hurdles to the study of the ...

生物学

Serial Enrichment of Spermatogonial Stem and Progenitor Cells (SSCs) in Culture for Derivation of Long-term Adult Mouse SSC Lines

Spermatogonial stem and progenitor cells (SSCs) of the testis represent a classic example of adult mammalian stem cells and preserve fertility for nearly the lifetime of the animal. While the precise mechanisms that govern self-renewal and differentiation in vivo are challenging to study, various systems have been developed previously to propagate murine SSCs in vitro using a combination of specialized culture media and feeder cells1-3.
Most in vitro forays into the biology of SSCs have derived cell lines from neonates, possibly due to the difficulty in obtaining adult cell lines4. However, the testis continues to mature up until ~5 weeks of age in most mouse strains. In the early post-natal period, dramatic changes occur in the architecture of the testis and in the biology of both somatic and spermatogenic cells, including alterations in expression levels of numerous stem cell-related genes. Therefore, neonatally-derived SSC lines may not fully recapitulate the biology of adult SSCs that persist after the adult testis has reached a steady state.
Several factors have hindered the production of adult SSC lines historically. First, the proportion of functional stem cells may decrease during adulthood, either due to intrinsic or extrinsic factors5,6. Furthermore, as with other adult stem cells, it has been difficult to enrich SSCs sufficiently from total adult testicular cells without using a combination of immunoselection or other sorting strategies7. Commonly employed strategies include the use of cryptorchid mice as a source of donor cells due to a higher ratio of stem cells to other cell types8. Based on the hypothesis that removal of somatic cells from the initial culture disrupts interactions with the stem cell niche that are essential for SSC survival, we previously developed methods to derive adult lines that do not require immunoselection or cryptorchid donors but rather employ serial enrichment of SSCs in culture, referred to hereafter as SESC2,3.
The method described below entails a simple procedure for deriving adult SSC lines by dissociating adult donor seminiferous tubules, followed by plating of cells on feeders comprised of a testicular stromal cell line (JK1)3. Through serial passaging, strongly adherent, contaminating non-germ cells are depleted from the culture with concomitant enrichment of SSCs. Cultures produced in this manner contain a mixture of spermatogonia at different stages of differentiation, which contain SSCs, based on long-term self renewal capability. The crux of the SESC method is that it enables SSCs to make the difficult transition from self-renewal in vivo to long-term self-renewal in vitro in a radically different microenvironment, produces long-term SSC lines, free of contaminating somatic cells, and thereby enables subsequent experimental manipulation of SSCs.

Serial Enrichment of Spermatogonial Stem and Progenitor Cells SSCs in Culture for Derivation of Long-term Adult Mouse SSC Lines

A simple method to derive and maintain spermatogonial stem and progenitor cell lines from adult mice is presented here. The method utilizes feeder cells originating from the somatic cell compartment of the adult mouse testis. This technique is applicable to common mouse strains, including transgenic, knock-out, and knock-in mice.

在文化序列富集的精原干细胞和祖细胞（SSCS）推导长期成年小鼠SSC线

Spermatogonial stem and progenitor cells (SSCs) of the testis represent a classic example of adult mammalian stem cells and preserve fertility for nearly ...

Separation of Spermatogenic Cell Types Using STA-PUT Velocity Sedimentation

Mammalian spermatogenesis is a complex differentiation process that occurs in several stages in the seminiferous tubules of the testes. Currently, there is no reliable cell culture system allowing for spermatogenic differentiation in vitro, and most biological studies of spermatogenic cells require tissue harvest from animal models like the mouse and rat. Because the testis contains numerous cell types - both non-spermatogenic (Leydig, Sertoli, myeloid, and epithelial cells) and spermatogenic (spermatogonia, spermatocytes, round spermatids, condensing spermatids and spermatozoa) - studies of the biological mechanisms involved in spermatogenesis require the isolation and enrichment of these different cell types. The STA-PUT method allows for the separation of a heterogeneous population of cells - in this case, from the testes - through a linear BSA gradient. Individual cell types sediment with different sedimentation velocity according to cell size, and fractions enriched for different cell types can be collected and utilized in further analyses. While the STA-PUT method does not result in highly pure fractions of cell types, e.g. as can be obtained with certain cell sorting methods, it does provide a much higher yield of total cells in each fraction (~1 x 108 cells/spermatogenic cell type from a starting population of 7-8 x 108 cells). This high yield method requires only specialized glassware and can be performed in any cold room or large refrigerator, making it an ideal method for labs that have limited access to specialized equipment like a fluorescence activated cell sorter (FACS) or elutriator.

The STA-PUT method allows for the separation of different populations of spermatogenic cells based on size and density.

生精细胞类型使用STA把速度沉降分离

Mammalian spermatogenesis is a complex  differentiation process that occurs in several stages in the seminiferous  tubules of the testes. Currently, there ...

Slide Preparation Method to Preserve Three-dimensional Chromatin Architecture of Testicular Germ Cells

During testicular germ cell differentiation, the structure of nuclear chromatin dynamically changes. The following describes a method designed to preserve the three-dimensional chromatin arrangement of testicular germ cells found in mice; this method has been termed as the three-dimensional (3D) slide method. In this method, testicular tubules are directly treated with a permeabilization step that removes cytoplasmic material, followed by a fixation step that fixes nuclear materials. Tubules are then dissociated, the cell suspension is cytospun, and cells adhere to slides. This method improves sensitivity towards detection of subnuclear structures and is applicable for immunofluorescence, DNA, and RNA fluorescence in situ hybridization (FISH) and the combination of these detection methods. As an example of a possible application of the 3D slide method, a Cot-1 RNA FISH is shown to detect nascent RNAs. The 3D slide method will facilitate the detailed examination of spatial relationships between chromatin structure, DNA, and RNA during testicular germ cell differentiation.

The material here describes a method developed to preserve the three-dimensional chromatin structure of testicular germ cells. This has been termed the three-dimensional (3D) slide method. This method improves sensitivity for detection of subnuclear structures and is applicable for immunofluorescence, DNA, and RNA fluorescence in situ hybridization (FISH).

幻灯片制备方法，以保存睾丸细菌细胞的三维染色质结构

During testicular germ cell differentiation, the structure of nuclear chromatin dynamically changes. The following describes a method designed to preserve ...