作者要感谢微生物学，免疫学和生物化学系高级插图师Tim Higgins先生提供技术视频协助; Matthew W. Wilson博士进行讨论，还有Jablonski和Morales-Tirado实验室的成员对他们的帮助意见。这项工作得到了阿尔康研究院青年研究员奖（VMM-T），田纳西大学研究基金会（VMM-T），国家眼科学院EY021200（MMJ），格温奖学金（VMM-T）等的支持。格温博士后研究金（ZKG），国防军医学研究和物资司令部（VMM-T）以及研究预防盲人无限制赠款。

<ol>
	<li>Flammer, J., Orgul, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optic+nerve+blood-flow+abnormalities+in+glaucoma.">Optic nerve blood-flow abnormalities in glaucoma.</a> Prog Retin Eye Res. 17 (2), 267-289 (1998).</li><li>Bathija, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optic+nerve+blood+flow+in+glaucoma.">Optic nerve blood flow in glaucoma.</a> Clin Exp Optom. 83 (3), 180-184 (2000).</li><li>Osborne, N. N., Melena, J., Chidlow, G., Wood, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+hypothesis+to+explain+ganglion+cell+death+caused+by+vascular+insults+at+the+optic+nerve+head:+possible+implication+for+the+treatment+of+glaucoma.">A hypothesis to explain ganglion cell death caused by vascular insults at the optic nerve head: possible implication for the treatment of glaucoma.</a> Br J Ophthalmol. 85 (10), 1252-1259 (2001).</li><li>Morgan, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circulation+and+axonal+transport+in+the+optic+nerve.">Circulation and axonal transport in the optic nerve.</a> Eye (Lond). 18 (11), 1089-1095 (2004).</li><li>Tian, N., Hwang, T. N., Copenhagen, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+excitatory+and+inhibitory+spontaneous+synaptic+activity+in+mouse+retinal+ganglion+cells.">Analysis of excitatory and inhibitory spontaneous synaptic activity in mouse retinal ganglion cells.</a> J Neurophysiol. 80 (3), 1327-1340 (1998).</li><li>Schmidt, K. G., Bergert, H., Funk, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neurodegenerative+diseases+of+the+retina+and+potential+for+protection+and+recovery.">Neurodegenerative diseases of the retina and potential for protection and recovery.</a> Curr Neuropharmacol. 6 (2), 164-178 (2008).</li><li>Dreher, B., Sefton, A. J., Ni, S. Y., Nisbett, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+morphology,+number,+distribution+and+central+projections+of+Class+I+retinal+ganglion+cells+in+albino+and+hooded+rats.">The morphology, number, distribution and central projections of Class I retinal ganglion cells in albino and hooded rats.</a> Brain Behav Evol. 26 (1), 10-48 (1985).</li><li>Williams, R. W., Strom, R. C., Rice, D. S., Goldowitz, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+and+environmental+control+of+variation+in+retinal+ganglion+cell+number+in+mice.">Genetic and environmental control of variation in retinal ganglion cell number in mice.</a> J Neurosci. 16 (22), 7193-7205 (1996).</li><li>Jeon, C. J., Strettoi, E., Masland, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+major+cell+populations+of+the+mouse+retina.">The major cell populations of the mouse retina.</a> J Neurosci. 18 (21), 8936-8946 (1998).</li><li>Surgucheva, I., Weisman, A. D., Goldberg, J. L., Shnyra, A., Surguchov, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gamma-synuclein+as+a+marker+of+retinal+ganglion+cells.">Gamma-synuclein as a marker of retinal ganglion cells.</a> Mol Vis. 14, 1540-1548 (2008).</li><li>Nadal-Nicolas, F. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brn3a+as+a+marker+of+retinal+ganglion+cells:+qualitative+and+quantitative+time+course+studies+in+naive+and+optic+nerve-injured+retinas.">Brn3a as a marker of retinal ganglion cells: qualitative and quantitative time course studies in naive and optic nerve-injured retinas.</a> Invest Ophthalmol Vis Sci. 50 (8), 3860-3868 (2009).</li><li>Kwong, J. M., Caprioli, J., Piri, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA+binding+protein+with+multiple+splicing:+a+new+marker+for+retinal+ganglion+cells.">RNA binding protein with multiple splicing: a new marker for retinal ganglion cells.</a> Invest Ophthalmol Vis Sci. 51 (2), 1052-1058 (2010).</li><li>Van Bergen, N. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recharacterization+of+the+RGC-5+retinal+ganglion+cell+line.">Recharacterization of the RGC-5 retinal ganglion cell line.</a> Invest Ophthalmol Vis Sci. 50 (9), 4267-4272 (2009).</li><li>Wood, J. P., Chidlow, G., Tran, T., Crowston, J. G., Casson, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+differentiation+protocols+for+RGC-5+cells.">A comparison of differentiation protocols for RGC-5 cells.</a> Invest Ophthalmol Vis Sci. 51 (7), 3774-3783 (2010).</li><li>Barres, B. A., Silverstein, B. E., Corey, D. P., Chun, L. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunological,+morphological,+and+electrophysiological+variation+among+retinal+ganglion+cells+purified+by+panning.">Immunological, morphological, and electrophysiological variation among retinal ganglion cells purified by panning.</a> Neuron. 1 (9), 791-803 (1998).</li><li>Hong, S., Iizuka, Y., Kim, C. Y., Seong, G. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+primary+mouse+retinal+ganglion+cells+using+immunopanning-magnetic+separation.">Isolation of primary mouse retinal ganglion cells using immunopanning-magnetic separation.</a> Mol Vis. 18, 2922-2930 (2012).</li><li>Julius, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+sensitivity+of+exponentials+and+other+curves+to+their+parameters.">The sensitivity of exponentials and other curves to their parameters.</a> Comput Biomed Res. 5 (5), 473-478 (1972).</li><li>Reif, A. E., Allen, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Akr+Thymic+Antigen+and+Its+Distribution+in+Leukemias+and+Nervous+Tissues.">The Akr Thymic Antigen and Its Distribution in Leukemias and Nervous Tissues.</a> J Exp Med. 120, 413-433 (1964).</li><li>Watanabe, M., Noguchi, T., Tsukada, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regional,+cellular,+and+subcellular+distribution+of+Thy-1+antigen+in+rat+nervous+tissues.">Regional, cellular, and subcellular distribution of Thy-1 antigen in rat nervous tissues.</a> Neurochem Res. 6 (5), 507-519 (1981).</li><li>Haeryfar, S. M., Hoskin, 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=Thy-1:+more+than+a+mouse+pan-T+cell+marker.">Thy-1: more than a mouse pan-T cell marker.</a> J Immunol. 173 (6), 3581-3588 (2004).</li><li>Sahagun, G., Moore, S. A., Fabry, Z., Schelper, R. L., Hart, M. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+of+murine+endothelial+cell+cultures+by+flow+cytometry+using+fluorescein-labeled+griffonia+simplicifolia+agglutinin.">Purification of murine endothelial cell cultures by flow cytometry using fluorescein-labeled griffonia simplicifolia agglutinin.</a> Am J Pathol. 134 (6), 1227-1232 (1989).</li><li>Shoge, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rat+retinal+ganglion+cells+culture+enriched+with+the+magnetic+cell+sorter.">Rat retinal ganglion cells culture enriched with the magnetic cell sorter.</a> Neurosci Lett. 259 (2), 111-114 (1999).</li><li>Chintalapudi, S. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+Molecular+Profiling+of+Primary+Mouse+Retinal+Ganglion+Cells:+Comparison+of+Phenotypes+from+Healthy+and+Glaucomatous+Retinas.">Isolation and Molecular Profiling of Primary Mouse Retinal Ganglion Cells: Comparison of Phenotypes from Healthy and Glaucomatous Retinas.</a> Front Aging Neurosci. 8, 93 (2016).</li><li>Nagdeve, N. G., Yaddanapudi, S., Pandav, S. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+different+doses+of+ketamine+on+intraocular+pressure+in+anesthetized+children.">The effect of different doses of ketamine on intraocular pressure in anesthetized children.</a> J Pediatr Ophthalmol Strabismus. 43 (4), 219-223 (2006).</li><li>Ding, C., Wang, P., Tian, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+general+anesthetics+on+IOP+in+elevated+IOP+mouse+model.">Effect of general anesthetics on IOP in elevated IOP mouse model.</a> Exp Eye Res. 92 (6), 512-520 (2011).</li><li>Schmittgen, T. D., Livak, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analyzing+real-time+PCR+data+by+the+comparative+C(T)+method.">Analyzing real-time PCR data by the comparative C(T) method.</a> Nat Protoc. 3 (6), 1101-1108 (2008).</li><li>Aerts, J., Nys, J., Arckens, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+highly+reproducible+and+straightforward+method+to+perform+in+vivo+ocular+enucleation+in+the+mouse+after+eye+opening.">A highly reproducible and straightforward method to perform in vivo ocular enucleation in the mouse after eye opening.</a> J Vis Exp. (92), e51936 (2014).</li><li>Li, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Loss+of+AP-2delta+reduces+retinal+ganglion+cell+numbers+and+axonal+projections+to+the+superior+colliculus.">Loss of AP-2delta reduces retinal ganglion cell numbers and axonal projections to the superior colliculus.</a> Mol Brain. 9 (1), 62 (2016).</li><li>Moshiri, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Near+complete+loss+of+retinal+ganglion+cells+in+the+math5/brn3b+double+knockout+elicits+severe+reductions+of+other+cell+types+during+retinal+development.">Near complete loss of retinal ganglion cells in the math5/brn3b double knockout elicits severe reductions of other cell types during retinal development.</a> Dev Biol. 316 (2), 214-227 (2008).</li><li>Danias, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+analysis+of+retinal+ganglion+cell+(RGC)+loss+in+aging+DBA/2NNia+glaucomatous+mice:+comparison+with+RGC+loss+in+aging+C57/BL6+mice.">Quantitative analysis of retinal ganglion cell (RGC) loss in aging DBA/2NNia glaucomatous mice: comparison with RGC loss in aging C57/BL6 mice.</a> Invest Ophthalmol Vis Sci. 44 (12), 5151-5162 (2003).</li><li>Jakobs, T. C., Ben, Y., Masland, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD15+immunoreactive+amacrine+cells+in+the+mouse+retina.">CD15 immunoreactive amacrine cells in the mouse retina.</a> J Comp Neurol. 465 (3), 361-371 (2003).</li><li>Uusitalo, M., Schlotzer-Schrehardt, U., Kivela, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrastructural+localization+of+the+HNK-1+carbohydrate+epitope+to+glial+and+neuronal+cells+of+the+human+retina.">Ultrastructural localization of the HNK-1 carbohydrate epitope to glial and neuronal cells of the human retina.</a> Invest Ophthalmol Vis Sci. 44 (3), 961-964 (2003).</li><li>Jackson, C. J., Garbett, P. K., Nissen, B., Schrieber, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Binding+of+human+endothelium+to+Ulex+europaeus+I-coated+Dynabeads:+application+to+the+isolation+of+microvascular+endothelium.">Binding of human endothelium to Ulex europaeus I-coated Dynabeads: application to the isolation of microvascular endothelium.</a> J Cell Sci. 96 ( Pt 2), 257-262 (1990).</li><li>Pennartz, S., Perraut, M., Pfrieger, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+of+retinal+ganglion+cells+from+postnatal+rats+by+magnetic+cell+sorting.">Purification of retinal ganglion cells from postnatal rats by magnetic cell sorting.</a> MACSmore. 12 (2), 16-18 (2010).</li><li>Nadal-Nicolas, F. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Displaced+retinal+ganglion+cells+in+albino+and+pigmented+rats.">Displaced retinal ganglion cells in albino and pigmented rats.</a> Front Neuroanat. 8, 99 (2014).</li><li>Nadal-Nicolas, F. M., Salinas-Navarro, M., Vidal-Sanz, M., Agudo-Barriuso, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two+methods+to+trace+retinal+ganglion+cells+with+fluorogold:+from+the+intact+optic+nerve+or+by+stereotactic+injection+into+the+optic+tract.">Two methods to trace retinal ganglion cells with fluorogold: from the intact optic nerve or by stereotactic injection into the optic tract.</a> Exp Eye Res. 131, 12-19 (2015).</li><li>Barnstable, C. J., Drager, U. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thy-1+antigen:+a+ganglion+cell+specific+marker+in+rodent+retina.">Thy-1 antigen: a ganglion cell specific marker in rodent retina.</a> Neuroscience. 11 (4), 847-855 (1984).</li><li>Chiu, K., Lau, W. M., Yeung, S. C., Chang, R. C., So, K. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Retrograde+labeling+of+retinal+ganglion+cells+by+application+of+fluoro-gold+on+the+surface+of+superior+colliculus.">Retrograde labeling of retinal ganglion cells by application of fluoro-gold on the surface of superior colliculus.</a> J Vis Exp. (16), (2008).</li></ol>

作者宣称他们没有竞争的经济利益。

FACS是净化细胞群体的首选技术。其他分离方法包括免疫沉淀，磁珠和补体固定消耗。 FACS与这些其他方法的优点是基于同时鉴别具有不同程度的强度的细胞表面标志物。分子的荧光强度与蛋白质表达量成比例。到目前为止，RGC的分离仅基于Thy1（CD90）阳性和CD48阴性15,16,22,34，而不管使用的分离方法如何。最近已经显示，Thy1 + CD48 neg表型不足以分离表达RGC细胞内标志物23的细胞的均匀群体。鉴定RGC群体对其分离至关重要，特别是因为它们包含小百分比的视网膜细胞7,8,9 。大多数RGC位于视网膜的最内层，而少数位于内丛状层（置换RGC35）中。因此，通过立体定向注射和跟踪羟睾丸素（用于引导神经元的逆行示踪剂）追踪RGC，成为许多实验室36,37,38的有吸引力的选择。这些系统需要注射示踪剂，如果不适当地执行，可能导致一些视网膜区域未被标记。此外，它们在技术上要求更高，并且像其他方法如免疫方法一样冗长。使用抗Thy1和-CD48抗体的免疫染色需要48小时才能完成，不能达到95以上％纯度。该工作描述了基于FACS的方法，其提供了快速和可重现的方案，以分离具有CD90.2 + CD48 阴性 CD15 阴性 CD57 阴性表型的活的RGC的均质群体，而不使用任何示踪剂，磁珠或免疫调节技术。 通过FACS成功分离纯RGC需要以下因素:1）分类效率，这取决于所使用的设备; 2）抗体标记的荧光染料的最佳组合，以减少噪音;和3）细胞分选设置。排序效率是通过将所选择的目标事件的数量除以检测到的目标事件的数量，以百分比表示来计算的。排序效率是由设备提供的计算。这种效率取决于分选系统的设置和细胞分选模式。选择荧光染料的最佳组合是一个复杂的过程。每次流感色相具有不同的特性，其特征在于其激发和发射波长。当用激光读取激发时，发射由光电倍增管读取，该光电倍增管由FACS分选设备中可用的光学滤波器限制。在此，提供抗体标记的荧光染料PE，PE-Cyanine7，AF700和BV421的组合。这是考虑到提供最佳分辨率同时减少光谱重叠的多种荧光染料组合来确定的。最后，排序设置至关重要。一般来说，视网膜细胞是脆弱的。因此，最好使用较低的压力来运行样品，以最小化细胞上的应力。将样品保持在4°C是关键的，因为在室温下保持鼠RGCs较长时间可以降低细胞产量，特别是当分选大量细胞时。 基于FACS的排序是隔离组成细胞的理想方法少量细胞悬液。与免疫沉淀和示踪剂系统相比，从视网膜剥离到细胞分选完成的过程需要大约5-6小时，这需要几天的时间才能完成。 FACS的多维分析和设备收集几个可行的群体的能力允许细胞的进一步功能分析。这里描述的方案是分离原代鼠RGCs的有力工具。尽管它具有多重优点，包括其灵敏度，重现性和立即鉴定活细胞，但是存在一些限制。首先，它需要昂贵的仪器和高度训练的操作员。通常，操作者是实地的免疫学家或训练有素的个人，在实验设置时与他们会面。如今，学术设施有多个核心设施，可以促进执行这些类型的实验。其次，RGCs失去了自己的力量由于排毒引起的皮肤形态，使其尺寸非常小。在这个时候，不知道他们的一些基因是否可能由于排毒而被调节。 本文介绍的方法可以在体外对RGC功能进行下游分析，是在视觉和健康科学领域中使用的有价值的工具。维持神经节细胞输出到大脑是视觉感知所必需的，并且在多种疾病中处于危险之中。这些细胞可以在健康和疾病模型中用于受控的体外实验。可以对这些细胞进行电生理，药理，生物化学和分子研究，这对于未来治疗靶标的发展是理想的。

RGC是终末分化的神经元，因此，原代细胞是实验所必需的。用于分离和富集原代小鼠视网膜神经节细胞（RGC）的方案的开发是揭示RGC健康和体外变性的机制的基础。这对于寻求产生潜在疗法以促进RGC功能并尽量减少死亡率的研究尤为重要。 RGC的变性与视网膜退行性疾病如青光眼，糖尿病性视网膜病变和正常衰老有关。虽然RGC损失的具体细胞机制尚不清楚，但已经确定了一系列危险因素。缺乏视神经头1,2,3的氧合导致RGC死亡4 ，并且作为兴奋性和i激活之间的动态平衡的干扰个体RGCs内的抑制性受体5,6 。一系列挑战妨碍了使用这些细胞进行深入研究的进展。首先，鼠视网膜中RGCs的数量很少。 RGC占总视网膜细胞7,8,9的不到1％。第二，大多数RGC特异性标记物是细胞内蛋白质10,11,12 。基于这些标记的选择使细胞不可行，这排除了下游功能分析。最后，目前可用的协议冗长，缺乏标准化13,14 。早期RGC分离方案是基于免疫方法。 Barres 等人 15 适应经典免疫基于对抗胸腺细胞抗原（也称Thy1）（细胞表面标记）的免疫阳性，在阳性选择之前，将大部分视网膜细胞从单核细胞和内皮细胞排除第二步。几年后，Hong et al。组合磁珠分离技术与细胞分选策略分离更高纯度的RGC 16 。在许多科学应用中仍然使用磁珠。一起，磁珠和流式细胞术方案提高了分离细胞的纯度。然而，这些纯化系统尚未被标准化用于从解离的视网膜分离鼠RGCs。 流式细胞仪是一种强大的分析方法，可以测量细胞悬浮液的光学和荧光特性。以高水平的灵敏度定量和定性分析细胞，为细胞群体提供多维分析通货膨胀。细胞鉴别基于两个主要物理性质:细胞大小或表面积，粒度或内部复杂性17 。可以通过组合具有类似激发波长和不同排放物的荧光染料标记的抗体来进行多维分析。流式细胞术是快速，可重复和敏感的。多重激光器通过流式细胞术允许单个细胞的更多的多维分析。因此，它是研究细胞学标本的有吸引力的方法。荧光激活细胞分选（FACS）使用通过流式细胞术鉴定的多维表型差异将单个细胞分类为不同的亚群。 在过去十年中，多种表面和细胞内蛋白已被鉴定为用于选择细胞（包括神经元）的潜在生物标志物。试图从大鼠中分离RGC的初步研究使用Thy1作为神经节细胞l标记。不幸的是，Thy1， 也就是 CD90，在其他啮齿动物物种18,19,20中具有多个同种型，并且由多个视网膜细胞类型19,20表达，使其成为RGC的非特异性标记。在视网膜中的单核细胞群体中发现另一个表面标志物CD48，包括巨噬细胞和小神经胶质细胞。使用这两个表面标记，修饰的RGC特征-Thy1 +和CD48 neg细胞 - 被开发出15,16,21,22。不幸的是，这两个选择标准不足以选择高度富集的研资局人口。为了解决这一未满足的需求，基于多层次正，负选择标准，开发了流式细胞仪方案23已知的细胞表面标志物以富集和纯化原代鼠RGC。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Anti-mouse CD15 PE</td>
			<td>BioLegend</td>
			<td>125606</td>
			<td>Clone MC-480</td>
		</tr>
		<tr>
			<td>Anti-mouse CD48 PE-Cy7</td>
			<td>BioLegend</td>
			<td>103424</td>
			<td>Clone HM48-1</td>
		</tr>
		<tr>
			<td>Anti-mouse CD57</td>
			<td>Sigma Aldrich</td>
			<td>C6680-100TST</td>
			<td>Clone VC1.1</td>
		</tr>
		<tr>
			<td>Anti-mouse CD90.2 AF700</td>
			<td>BioLegend</td>
			<td>105320</td>
			<td>Clone 30-H12</td>
		</tr>
		<tr>
			<td>Brilliant Violet 421 Goat Anti-mouse IgG</td>
			<td>BioLegend</td>
			<td>405317</td>
			<td>Clone Poly4053</td>
		</tr>
		<tr>
			<td>Purified Anti-mouse CD16/32</td>
			<td>BioLegend</td>
			<td>101302</td>
			<td>FcgRII/III block, Clone 93</td>
		</tr>
		<tr>
			<td>Zombie Aqua&#160;</td>
			<td>BioLegend</td>
			<td>423102</td>
			<td>Live cell/ Dead cell discrimination</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum</td>
			<td>Hyclone</td>
			<td>SH30071.03</td>
			<td>U.S. origin</td>
		</tr>
		<tr>
			<td>AbC Total Antibody Compensation Bead Kit</td>
			<td>Thermo Fisher Scientific</td>
			<td>A10497</td>
			<td>Multi-species Ig</td>
		</tr>
		<tr>
			<td>Neurobasal Medium</td>
			<td>Thermo Fisher Scientific</td>
			<td>21103049</td>
			<td>Add serum to media prior to culture.</td>
		</tr>
		<tr>
			<td>Phosphate-Buffered Saline (PBS)</td>
			<td>Thermo Fisher Scientific</td>
			<td>10010049</td>
			<td>Saline solution</td>
		</tr>
		<tr>
			<td>Dissection Microscope</td>
			<td>Olympus</td>
			<td>SZ-PT Model</td>
			<td>Stereo Microscope</td>
		</tr>
		<tr>
			<td>Sorvall Centrifuge</td>
			<td>Thermo Scientific</td>
			<td>ST 16R</td>
			<td>All centrifugation performed&#160; at RT</td>
		</tr>
		<tr>
			<td>Base Plate &#8211; Dissection Pan</td>
			<td>Fisher Scientific</td>
			<td>SB15233FIM</td>
			<td>A wax plate can also be used</td>
		</tr>
		<tr>
			<td>Forceps</td>
			<td>Aesculap</td>
			<td>5002-7</td>
			<td>4 &#189; inches</td>
		</tr>
		<tr>
			<td>Iris Scissors, Straight</td>
			<td>Aesculap</td>
			<td>1360</td>
			<td>5 &#189; inches</td>
		</tr>
		<tr>
			<td>Falcon 15 mL conical tubes</td>
			<td>Fisher Scientific</td>
			<td>352097</td>
			<td>Polypropylene tubes</td>
		</tr>
		<tr>
			<td>Falcon 50 mL conical tubes</td>
			<td>Fisher Scientific</td>
			<td>352098</td>
			<td>Polypropylene tubes</td>
		</tr>
		<tr>
			<td>BD FACS Tubes</td>
			<td>Fisher Scientific</td>
			<td>352003</td>
			<td>Polypropylene tubes</td>
		</tr>
		<tr>
			<td>40 mm dishes</td>
			<td>MidSci</td>
			<td>TP93040</td>
			<td>Tissue culture treated</td>
		</tr>
		<tr>
			<td>70 &#956;m nylon strainer</td>
			<td>MidSci</td>
			<td>70ICS</td>
			<td>sterile</td>
		</tr>
		<tr>
			<td>40 &#956;m nylon strainer</td>
			<td>MidSci</td>
			<td>40ICS</td>
			<td>sterile</td>
		</tr>
		<tr>
			<td>&#160;BD 10 mL syringe</td>
			<td>Fisher Scientific</td>
			<td>301604</td>
			<td>Disposable Syringe without needle</td>
		</tr>
		<tr>
			<td>Pestles</td>
			<td>MidSci</td>
			<td>PEST</td>
			<td>sterile</td>
		</tr>
		<tr>
			<td>Wheaton Vials</td>
			<td>Fisher Scientific</td>
			<td>986734</td>
			<td>No Liner</td>
		</tr>
		<tr>
			<td>BD 30 G needle</td>
			<td>Fisher Scientific</td>
			<td>305128</td>
			<td>1 inch</td>
		</tr>
		<tr>
			<td>Hausser Scientific Bright-Line Glass Counting Chamber</td>
			<td>Fisher Scientific</td>
			<td>0267151B</td>
			<td>Hemocytometer</td>
		</tr>
		<tr>
			<td>Gibco Trypan blue 0.4% Solution</td>
			<td>Fisher Scientific</td>
			<td>15250061</td>
			<td>Viability Dye</td>
		</tr>
		<tr>
			<td>Eppendorf tubes</td>
			<td>Fisher Scientific</td>
			<td>05-402-25</td>
			<td>1.5mL</td>
		</tr>
		<tr>
			<td>EVOS Floid Cell Imaging</td>
			<td>Thermo Fisher Scientific</td>
			<td>447113</td>
			<td>Fluorescence Imaging with a 20x objective</td>
		</tr>
		<tr>
			<td>100% Ethanol</td>
			<td>Fisher Scientific</td>
			<td>04-355-452</td>
			<td>Used to make 70% Ethanol</td>
		</tr>
		<tr>
			<td>Pipet-Lite LTS Pipette L-1000XLS+</td>
			<td>Rainin</td>
			<td>17014282</td>
			<td>LTS Pipette</td>
		</tr>
		<tr>
			<td>Pipet-Lite LTS Pipette L-200XLS+</td>
			<td>Rainin</td>
			<td>17014391</td>
			<td>LTS Pipette</td>
		</tr>
		<tr>
			<td>Pipet-Lite LTS Pipette L-20XLS+</td>
			<td>Rainin</td>
			<td>17014392</td>
			<td>LTS Pipette</td>
		</tr>
		<tr>
			<td>Rack LTS 1000 mL &#8211; GPS-L1000S</td>
			<td>Rainin</td>
			<td>17005088</td>
			<td>Blue Rack Sterile Tips</td>
		</tr>
		<tr>
			<td>Rack LTS 250 mL &#8211; GPS-L250S</td>
			<td>Rainin</td>
			<td>17005092</td>
			<td>Green Rack Sterile Tips</td>
		</tr>
		<tr>
			<td>Rack LTS 20 mL &#8211; GPS-L10S</td>
			<td>Rainin</td>
			<td>17005090</td>
			<td>Red Rack Sterile Tips</td>
		</tr>
		<tr>
			<td>FACSAria II Cell Sorter</td>
			<td>BD Biosciences</td>
			<td>N/A</td>
			<td>Custom order</td>
		</tr>
		<tr>
			<td>LSR II Cytometer</td>
			<td>BD Biosciences</td>
			<td>N/A</td>
			<td>Custom order</td>
		</tr>
		<tr>
			<td>Abca8a</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00462440_m1</td>
			<td>M&#252;ller cells</td>
		</tr>
		<tr>
			<td>Aldh1al</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00657317_m1</td>
			<td>M&#252;ller cells</td>
		</tr>
		<tr>
			<td>Aqp4</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00802131_m1</td>
			<td>Astrocytes</td>
		</tr>
		<tr>
			<td>Calb2</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00801461_m1</td>
			<td>Amacrine, Horizontal</td>
		</tr>
		<tr>
			<td>Cd68</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm03047340_m1</td>
			<td>Retinal Pigment Epithelial Cells</td>
		</tr>
		<tr>
			<td>Gad2</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00484623_m1</td>
			<td>Amacrine</td>
		</tr>
		<tr>
			<td>Hprt</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm01545399_m1</td>
			<td>House keeping gene</td>
		</tr>
		<tr>
			<td>Lhx1</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm01297482_m1</td>
			<td>Horizontal</td>
		</tr>
		<tr>
			<td>Lim2</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00624623_m1</td>
			<td>Horizontal</td>
		</tr>
		<tr>
			<td>Nrl</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00476550_m1</td>
			<td>Photoreceptors</td>
		</tr>
		<tr>
			<td>Ntrk1</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm01219406_m1</td>
			<td>Horizontal</td>
		</tr>
		<tr>
			<td>Pcp4</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00500973_m1</td>
			<td>Bipolar, Amacrine</td>
		</tr>
		<tr>
			<td>Pou4f1</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm02343791_m1</td>
			<td>Retinal Ganglion Cells</td>
		</tr>
		<tr>
			<td>Prdx6</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00725435_s1</td>
			<td>Astrocytes</td>
		</tr>
		<tr>
			<td>Prkca</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00440858_m1</td>
			<td>Bipolar</td>
		</tr>
		<tr>
			<td>Prox1</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00435969_m1</td>
			<td>Horizontal</td>
		</tr>
		<tr>
			<td>Pvalb</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00443100_m1</td>
			<td>Amacrine</td>
		</tr>
		<tr>
			<td>Rbpms</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm02343791_m1</td>
			<td>Retinal Ganglion Cells</td>
		</tr>
		<tr>
			<td>Rom1</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00436364_g1</td>
			<td>Photoreceptors</td>
		</tr>
		<tr>
			<td>Rpe65</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00504133_m1</td>
			<td>Retinal Pigment Epithelial cells</td>
		</tr>
		<tr>
			<td>Slc1a3</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00600697_m1</td>
			<td>Astrocytes</td>
		</tr>
		<tr>
			<td>Slc6a9</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00433662_m1</td>
			<td>Amacrine</td>
		</tr>
		<tr>
			<td>Sncg</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00488345_m1</td>
			<td>Retinal Ganglion Cells</td>
		</tr>
		<tr>
			<td>Tubb3</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm00727586_s1</td>
			<td>Retinal Ganglion Cells</td>
		</tr>
		<tr>
			<td>Vim</td>
			<td>Thermo Fisher Scientific</td>
			<td>Mm01333430_m1</td>
			<td>M&#252;ller cells</td>
		</tr>
		<tr>
			<td>Taqman Universal Master Mix</td>
			<td>Thermo Fisher Scientific</td>
			<td>4440047</td>
			<td>qPCR Reagent</td>
		</tr>
		<tr>
			<td>miRNeasy Mini Kit</td>
			<td>Qiagen</td>
			<td>217004</td>
			<td>RNA Isolation</td>
		</tr>
		<tr>
			<td>SuperScript VILO cDNA Synthesis Kit</td>
			<td>Thermo Fisher Scientific</td>
			<td>11754250</td>
			<td>cDNA synthesis</td>
		</tr>
		<tr>
			<td>Taqman PreAmp Master Mix</td>
			<td>Thermo Fisher Scientific</td>
			<td>4391128</td>
			<td>Pre-Amplification step</td>
		</tr>
		<tr>
			<td>BD Cytofix/ Cytoperm</td>
			<td>BD Biosciences</td>
			<td>554714</td>
			<td>Fixation/ Permeabilization Buffer</td>
		</tr>
		<tr>
			<td>BD Perm/ Wash</td>
			<td>BD Biosciences</td>
			<td>554723</td>
			<td>Permeabilization Solution</td>
		</tr>
		<tr>
			<td>RBPMS</td>
			<td>Santa Cruz Biotechnology</td>
			<td>sc-86815</td>
			<td>intracellular antibody</td>
		</tr>
		<tr>
			<td>SNCG</td>
			<td>Gene Tex</td>
			<td>GTX110483</td>
			<td>intracellular antibody</td>
		</tr>
		<tr>
			<td>BRN3A</td>
			<td>Santa Cruz Biotechnology</td>
			<td>sc-8429</td>
			<td>intracellular antibody</td>
		</tr>
		<tr>
			<td>TUJ1</td>
			<td>BioLegend</td>
			<td>801202</td>
			<td>intracellular antibody</td>
		</tr>
	</tbody>
</table>

isolation of primary murine retinal ganglion cells (rgcs) by flow cytometry

神经退行性疾病往往对受影响者有破坏性的影响。除了正常老化之外，视网膜神经节细胞（RGC）损失也涉及一系列疾病，包括糖尿病性视网膜病变和青光眼。尽管它们的重要性，RGC迄今为止非常难以研究，部分原因在于它们仅占视网膜中各种细胞的一小部分。此外，目前的分离方法使用细胞内标记来鉴定产生非活细胞的RGC。这些技术还涉及冗长的分离方案，因此缺乏获得和分离RGC的实用，标准化和可靠的方法。这项工作描述了一种有效，全面和可靠的方法，使用基于正选择标准和阴性选择标准的方案从小鼠视网膜分离原代RGC。所提出的方法允许未来RGCs的研究，目的是更好地了解专业由神经退行性疾病中功能性RGCs的丧失导致的视力下降。

<html> RGC的深入研究受到许多因素的阻碍，包括其频率低，缺乏强大和标准化的隔离方法。 图1显示了用于视网膜分离的方法。根据分析方法存在摘除程序的变化，例如摘除核素是体内实验的一部分27 。在安乐死小鼠中进行该方案的摘除。 如图1A- B所示，镊子被放置在眼睛下方并被拉起以引起最小的出血并用完整的视神经去除眼球。 在不同小鼠品系中RGC的数量存在差异，特别是在遗传改变的小鼠中，当确定使用的小鼠数量时，意识到这些差异是重要的，老的C57BL / 6J小鼠的视网膜比其年轻的对应物23具有更少的活的视网膜细胞，因此必须仔细地进行视网膜剥离视网膜剥离的逐步程序如图1C -J 所示，视网膜细胞是脆弱的，因此，将解剖的视网膜置于尼龙过滤器中，并用注射器的后端浸渍，如如图2A所示，或用于细胞过滤器的研杵，直接在细胞过滤器中浸泡细胞是快速的并且减少细胞团块， 图2B中示出了细胞悬浮液的代表性图像，可以观察到多个内部视网膜细胞。在这一点上，RGCs已经失去了他们的签名形象由于细胞分离期间的轴突切除术和细胞悬浮液的制备。 该方法的劳动密集度最高的步骤是细胞分选设置。这个阶段是多色FACS中的关键步骤，因为它可以最大限度地提高信噪比。 图3A显示了用于分离RGC的门控策略。该策略旨在从细胞悬浮液中除去污染细胞，其包括单核细胞，胶质细胞，无长大细胞和感光细胞。作为方法的一部分，在作为排除策略的一部分使用额外的表面标记物之前，通过免疫组织化学分析确认。以前的数据表明，少量的CD90.2 +细胞是CD48 + 。排除这些细胞从视网膜细胞池中除去单核细胞和可能的小胶质细胞。之前已经显示出经典的Thy1 + CD48 neg </sup&gt;表面表型不足以鉴定和分离鼠RGCs 23 ，因为这些细胞表达与无远处，Müller，双极，水平感光体和视网膜色素上皮细胞相关的基因（ 图4A ）。通过调查细胞排斥的其他标记来进一步解决这个问题。 CD15已被描述为无远处和双极细胞的标志物31 ，促使其作为负选择的附加标记物。 Uusitalo 等人的工作32描述了CD57作为胶质细胞和光感受器的鉴定标记。因此，将该抗体加入到细胞分选策略中。 接下来，这些细胞的特征在于验证分离鼠RGC的方法。 CD90.2 + CD48 阴性 CD15 阴性 CD57 阴性分类细胞（&lt;评估与RGC 10,11,12,33 :SNCG，BRN3A，TUJ1和RBPMS相关的以下细胞内标志物的表达的强力类="xfig"&gt;图3B）。 如图3C所示，分选的细胞表达所有四种与RGC相关的细胞内蛋白质。接下来， 图3D中使用成像流式细胞术显示RBPMS的细胞内定位和CD90.2的细胞表面表达。这些结果在多个细胞仪系统中进行了测试，证实了其重现性和标准化。 如图3E所示，一些分选的细胞开始显示体外细胞培养后与RGC相关的形态。 最后，比较浓缩前后细胞通过qPCR分析进行了分析。 Thy1 + CD48 neg表型与CD90.2 + CD48 neg CD15 neg CD57 neg分选细胞的比较表明Thy1 + CD48 neg表型与RGC相关的基因，也与其他视网膜细胞相关。然而，高度富集的分选细胞群体（ 图4B ）显示编码RGC特异性细胞内标志物Sncg （SNCG）， Pouf4I （BRN3A）， Tubb3 （TUJ1）和Rbpms （RBPMS）的基因的多倍增加。总的来说，mRNA和蛋白质评估验证了该方法。 <img alt="图1" class="xfigimg" src="/files/ftp_upload/55785/55785fig1.jpg" /> 图1 。视网膜分离的摘除和眼部解剖。年轻C57BL / 6J小鼠在t前进行安乐死o眼球去除与二氧化碳和子宫颈脱位。 A）将镊子放在眼睛下方，并在一个运动中拉起眼睛。 B）眼睛被去除，包括视神经。 CJ）逐步引导去除视网膜。 C）在去除角膜之前使用30G针进行穿刺，以允许房水离开眼睛。 D）用镊子保持角膜，做一个小切口。 EF）使用镊子可以剥离角膜，视网膜色素上皮，脉络膜和巩膜。视网膜与巩膜分离，滚动并移除。 G）将镜头取出并丢弃。 HJ）将收集的视网膜置于含有PBS / 1％FBS的小盘中，以保持其始终保持湿润。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55785/55785fig1large.jpg" target="_blank">请点击这里查看更大的版本</a>数字。 <img alt="图2" class="xfigimg" src="/files/ftp_upload/55785/55785fig2.jpg" /> 图2 。收集视网膜后视网膜细胞悬浮液。将收集的视网膜置于小盘中以分离细胞。 A）将视网膜置于70μm尼龙过滤器中，并使用注射器的后端浸渍。 B）细胞悬浮液的代表性图像，其中观察到不同的视网膜细胞。刻度棒为10μm。 <img alt="图3" class="xfigimg" src="/files/ftp_upload/55785/55785fig3.jpg" /> 图3 。用CD90.2 + CD48 neg CD15 neg CD57 分离细胞的分选策略 <strong&gt; neg 表型和后排序分析。分选策略基于CD90.2细胞的包含以及作为污染细胞的CD48-，CD15-和CD57-阳性细胞的排除。 A）作为第一步，绘图尺寸（FSC）和内部复杂度（SSC）以获得细胞群体的概述。初始门控群体（P1）用于使用SSC高度（H）对宽度（W），P2来区分单个细胞和结块细胞或聚集体。单细胞的选择用于选择CD90.2 + CD48 neg细胞。为了确认所有双峰的去除，执行FSC-H与FSC-W的图，P3（ 中间图 ）。用AF700缀合的抗小鼠CD90.2，PE-Cyanine7缀合的抗小鼠CD48，PE缀合的CD15和抗小鼠CD57标记细胞。作为标记抗小鼠CD57的二抗，使用抗小鼠BV421。人口3（P3）绘制在第四个&lt;/ em&gt;面板选择CD90.2 + CD48 neg细胞，去除大部分污染细胞。接下来，使用所选择的CD90.2 + CD48 neg细胞产生CD57对CD15图。选择象限4（Q4），因为它代表对CD15和CD57均为阴性的CD90.2 + CD48 neg细胞。所得门控群体的表型是CD90.2 + CD48 neg CD15 neg CD57 neg 。 B） A）中使用的表面标记的分类分析。排序的细胞的大小是均匀的，如第一个图所示。随后的直方图显示在A）中详细列出的排序策略中使用的每个表面标记的百分比。总共95％的细胞是CD90.2 + ，如黑色线所示，与Ig对照相比，由实心直方图表示。将这些细胞门控以评估由红色，蓝色和灰色代表的CD48，CD15和CD57的百分比n行。结果显示这些细胞表面标记的最小表达。 C）通过使用RGC特异性细胞内标记SNCG，BRN3A，TUJ1和RBPMS来确认RGC表型。黑线代表表达每个细胞内标志物的细胞的百分比。 D）在成像细胞分选器中拍摄的代表性图像，其显示RBPMS的细胞内定位，RGC特异性细胞内标志物和细胞表面标志物CD90.2。比例尺为20μm。 E）使用共焦显微镜培养24小时后分类的RGC的代表性图像。比例尺为20μm。图像BE改编自以前发布的工作，许可23 。图像DE在20X拍摄。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55785/55785fig3large.jpg" target="_blank">请点击此处查看此图的较大版本。</a> 图4 。前后分选mRNA分析。通过使用一组由视网膜细胞表达的25个基因的qPCR分析评估Thy1 + CD48 阴性和具有表型CD90.2 + CD48 neg CD15 neg CD57 neg的分选细胞。目标基因表达水平作为Log 2倍变化，使用Hprt作为管家基因，水作为阴性对照。基于ΔCT法进行计算。平均值±SEM; n = 3次生物重复进行一式三份。从以前出版的作品获得的数字23 。

Watch this Scientific Journal Video about Isolation of Primary Murine Retinal Ganglion Cells RGCs by Flow Cytometry at JoVE.com

Isolation of Primary Murine Retinal Ganglion Cells RGCs by Flow Cytometry

数百万人患有导致不可逆失明的视网膜退行性疾病。许多这些疾病的常见因素是视网膜神经节细胞（RGC）的丧失。该详细方案描述了通过流式细胞术的阳性和阴性选择分离原代鼠RGC。

通过流式细胞术分离原代小鼠视网膜神经节细胞（RGC）

Neurodegenerative diseases often have a devastating impact on those affected. Retinal ganglion cell (RGC) loss is implicated in an array of diseases, ...

isolation-primary-murine-retinal-ganglion-cells-rgcs-flow

Nanyang Technological University

Research

JoVE Journal

Bioengineering

Isolation of Primary Murine Retinal Ganglion Cells (RGCs) by Flow Cytometry

14.8K 次观看.  University of Tennessee Health Science Center. 数百万人患有导致不可逆失明的视网膜退行性疾病。许多这些疾病的常见因素是视网膜神经节细胞（RGC）的丧失。该详细方案描述了通过流式细胞术的阳性和阴性选择分离原代鼠RGC。 

视频: Isolation of Primary Murine Retinal Ganglion Cells RGCs by Flow Cytometry

Parallel-plate Flow Chamber and Continuous Flow Circuit to Evaluate Endothelial Progenitor Cells under Laminar Flow Shear Stress

The overall goal of this method is to describe a technique to subject adherent cells to laminar flow conditions and evaluate their response to well quantifiable fluid shear stresses1.
Our flow chamber design and flow circuit (Fig. 1) contains a transparent viewing region that enables testing of cell adhesion and imaging of cell morphology immediately before flow (Fig. 11A, B), at various time points during flow (Fig. 11C), and after flow (Fig. 11D). These experiments are illustrated with human umbilical cord blood-derived endothelial progenitor cells (EPCs) and porcine EPCs2,3.
This method is also applicable to other adherent cell types, e.g. smooth muscle cells (SMCs) or fibroblasts.
The chamber and all parts of the circuit are easily sterilized with steam autoclaving. In contrast to other chambers, e.g. microfluidic chambers, large numbers of cells (&gt; 1 million depending on cell size) can be recovered after the flow experiment under sterile conditions for cell culture or other experiments, e.g. DNA or RNA extraction, or immunohistochemistry (Fig. 11E), or scanning electron microscopy5. The shear stress can be adjusted by varying the flow rate of the perfusate, the fluid viscosity, or the channel height and width. The latter can reduce fluid volume or cell needs while ensuring that one-dimensional flow is maintained. It is not necessary to measure chamber height between experiments, since the chamber height does not depend on the use of gaskets, which greatly increases the ease of multiple experiments. Furthermore, the circuit design easily enables the collection of perfusate samples for analysis and/or quantification of metabolites secreted by cells under fluid shear stress exposure, e.g. nitric oxide (Fig. 12)6.

We are describing a method to subject adherent cells to laminar flow shear stress in a sterile continuous flow circuit. The cells' adhesion, morphology can be studied through the transparent chamber, samples obtained from the circuit for metabolite analysis and cells harvested after shear exposure for future experiments or culture.

平行板流动腔和评估内皮祖细胞层流剪应力下连续流电路

The overall goal of this method is to describe a technique to subject adherent cells to laminar flow conditions and evaluate their response to well ...

科研

生物工程

Analyzing Cellular Internalization of Nanoparticles and Bacteria by Multi-spectral Imaging Flow Cytometry

Nanoparticulate systems have emerged as valuable tools in vaccine delivery through their ability to efficiently deliver cargo, including proteins, to antigen presenting cells1-5. Internalization of nanoparticles (NP) by antigen presenting cells is a critical step in generating an effective immune response to the encapsulated antigen. To determine how changes in nanoparticle formulation impact function, we sought to develop a high throughput, quantitative experimental protocol that was compatible with detecting internalized nanoparticles as well as bacteria. To date, two independent techniques, microscopy and flow cytometry, have been the methods used to study the phagocytosis of nanoparticles. The high throughput nature of flow cytometry generates robust statistical data. However, due to low resolution, it fails to accurately quantify internalized versus cell bound nanoparticles. Microscopy generates images with high spatial resolution; however, it is time consuming and involves small sample sizes6-8. Multi-spectral imaging flow cytometry (MIFC) is a new technology that incorporates aspects of both microscopy and flow cytometry that performs multi-color spectral fluorescence and bright field imaging simultaneously through a laminar core. This capability provides an accurate analysis of fluorescent signal intensities and spatial relationships between different structures and cellular features at high speed.
	Herein, we describe a method utilizing MIFC to characterize the cell populations that have internalized polyanhydride nanoparticles or Salmonella enterica serovar Typhimurium. We also describe the preparation of nanoparticle suspensions, cell labeling, acquisition on an ImageStreamX system and analysis of the data using the IDEAS application. We also demonstrate the application of a technique that can be used to differentiate the internalization pathways for nanoparticles and bacteria by using cytochalasin-D as an inhibitor of actin-mediated phagocytosis.

In this article, we describe a method utilizing multi-spectral imaging flow cytometry to quantify the internalization of polyanhydride nanoparticles or bacteria by RAW 264.7 cells.

由多光谱成像流式细胞仪分析细胞内化纳米粒子和细菌

Nanoparticulate  systems have emerged as valuable tools in vaccine delivery through their  ability to efficiently deliver cargo, including proteins, to ...

Evaluation of Polymeric Gene Delivery Nanoparticles by Nanoparticle Tracking Analysis and High-throughput Flow Cytometry

Non-viral gene delivery using polymeric nanoparticles has emerged as an attractive approach for gene therapy to treat genetic diseases1 and as a technology for regenerative medicine2. Unlike viruses, which have significant safety issues, polymeric nanoparticles can be designed to be non-toxic, non-immunogenic, non-mutagenic, easier to synthesize, chemically versatile, capable of carrying larger nucleic acid cargo and biodegradable and/or environmentally responsive. Cationic polymers self-assemble with negatively charged DNA via electrostatic interaction to form complexes on the order of 100 nm that are commonly termed polymeric nanoparticles. Examples of biomaterials used to form nanoscale polycationic gene delivery nanoparticles include polylysine, polyphosphoesters, poly(amidoamines)s and polyethylenimine (PEI), which is a non-degradable off-the-shelf cationic polymer commonly used for nucleic acid delivery1,3 . Poly(beta-amino ester)s (PBAEs) are a newer class of cationic polymers4 that are hydrolytically degradable5,6 and have been shown to be effective at gene delivery to hard-to-transfect cell types such as human retinal endothelial cells (HRECs)7, mouse mammary epithelial cells8, human brain cancer cells9 and macrovascular (human umbilical vein, HUVECs) endothelial cells10.
A new protocol to characterize polymeric nanoparticles utilizing nanoparticle tracking analysis (NTA) is described. In this approach, both the particle size distribution and the distribution of the number of plasmids per particle are obtained11. In addition, a high-throughput 96-well plate transfection assay for rapid screening of the transfection efficacy of polymeric nanoparticles is presented. In this protocol, poly(beta-amino ester)s (PBAEs) are used as model polymers and human retinal endothelial cells (HRECs) are used as model human cells. This protocol can be easily adapted to evaluate any polymeric nanoparticle and any cell type of interest in a multi-well plate format.

A protocol for nanoparticle tracking analysis (NTA) and high-throughput flow cytometry to evaluate polymeric gene delivery nanoparticles is described. NTA is utilized to characterize the nanoparticle particle size distribution and the plasmid per particle distribution. High-throughput flow cytometry enables quantitative transfection efficacy evaluation for a library of gene delivery biomaterials.

高分子基因传递纳米粒子的纳米粒子跟踪分析和高通量流式细胞仪评价

Non-viral gene delivery using polymeric nanoparticles has emerged as an attractive approach for gene therapy to treat genetic diseases1 and as a ...

Wide-field Fluorescent Microscopy and Fluorescent Imaging Flow Cytometry on a Cell-phone

Fluorescent microscopy and flow cytometry are widely used tools in biomedical research and clinical diagnosis. However these devices are in general relatively bulky and costly, making them less effective in the resource limited settings. To potentially address these limitations, we have recently demonstrated the integration of wide-field fluorescent microscopy and imaging flow cytometry tools on cell-phones using compact, light-weight, and cost-effective opto-fluidic attachments. In our flow cytometry design, fluorescently labeled cells are flushed through a microfluidic channel that is positioned above the existing cell-phone camera unit. Battery powered light-emitting diodes (LEDs) are butt-coupled to the side of this microfluidic chip, which effectively acts as a multi-mode slab waveguide, where the excitation light is guided to uniformly excite the fluorescent targets. The cell-phone camera records a time lapse movie of the fluorescent cells flowing through the microfluidic channel, where the digital frames of this movie are processed to count the number of the labeled cells within the target solution of interest. Using a similar opto-fluidic design, we can also image these fluorescently labeled cells in static mode by e.g. sandwiching the fluorescent particles between two glass slides and capturing their fluorescent images using the cell-phone camera, which can achieve a spatial resolution of e.g. ~ 10 &mu;m over a very large field-of-view of ~ 81 mm2. This cell-phone based fluorescent imaging flow cytometry and microscopy platform might be useful especially in resource limited settings, for e.g. counting of CD4+ T cells toward monitoring of HIV+ patients or for detection of water-borne parasites in drinking water.

We review our recent results on the integration of fluorescent microscopy and imaging flow cytometry tools on a cell-phone using compact and cost-effective opto-fluidic attachments. These cell-phone based micro-analysis devices might be useful for cytometric analysis, such as performing various cell counting tasks as well as for high-throughput screening of e.g., water samples in resource limited settings.

一个手机上的宽视场荧光显微镜和荧光成像流式细胞仪

Fluorescent microscopy and flow cytometry are widely used tools in biomedical research and clinical diagnosis. However these devices are in general ...

Localization and Relative Quantification of Carbon Nanotubes in Cells with Multispectral Imaging Flow Cytometry

Carbon-based nanomaterials, like carbon nanotubes (CNTs), belong to this type of nanoparticles which are very difficult to discriminate from carbon-rich cell structures and de facto there is still no quantitative method to assess their distribution at cell and tissue levels. What we propose here is an innovative method allowing the detection and quantification of CNTs in cells using a multispectral imaging flow cytometer (ImageStream, Amnis). This newly developed device integrates both a high-throughput of cells and high resolution imaging, providing thus images for each cell directly in flow and therefore statistically relevant image analysis. Each cell image is acquired on bright-field (BF), dark-field (DF), and fluorescent channels, giving access respectively to the level and the distribution of light absorption, light scattered and fluorescence for each cell. The analysis consists then in a pixel-by-pixel comparison of each image, of the 7,000-10,000 cells acquired for each condition of the experiment. Localization and quantification of CNTs is made possible thanks to some particular intrinsic properties of CNTs: strong light absorbance and scattering; indeed CNTs appear as strongly absorbed dark spots on BF and bright spots on DF with a precise colocalization.
This methodology could have a considerable impact on studies about interactions between nanomaterials and cells given that this protocol is applicable for a large range of nanomaterials, insofar as they are capable of absorbing (and/or scattering) strongly enough the light.

In this study, the main purpose was to monitor the cellular uptake and eventual exocytosis of carbon nanotubes (CNTs). From this perspective, we proposed here a unique method using multispectral imaging flow cytometry allowing a quantification and localization of CNTs in a statistically relevant number of cells.

Carbon-based nanomaterials, like carbon nanotubes (CNTs), belong to this type of nanoparticles which are very difficult to discriminate from carbon-rich ...

Isolation of Primary Human Colon Tumor Cells from Surgical Tissues and Culturing Them Directly on Soft Elastic Substrates for Traction Cytometry

Cancer cells respond to matrix mechanical stiffness in a complex manner using a coordinated, hierarchical mechano-chemical system composed of adhesion receptors and associated signal transduction membrane proteins, the cytoskeletal architecture, and molecular motors1, 2. Mechanosensitivity of different cancer cells in vitro are investigated primarily with immortalized cell lines or murine derived primary cells, not with primary human cancer cells. Hence, little is known about the mechanosensitivity of primary human colon cancer cells in vitro. Here, an optimized protocol is developed that describes the isolation of primary human colon cells from healthy and cancerous surgical human tissue samples. Isolated colon cells are then successfully cultured on soft (2 kPa stiffness) and stiff (10 kPa stiffness) polyacrylamide hydrogels and rigid polystyrene (~3.6 GPa stiffness) substrates functionalized by an extracellular matrix (fibronectin in this case). Fluorescent microbeads are embedded in soft gels near the cell culture surface, and traction assay is performed to assess cellular contractile stresses using free open access software. In addition, immunofluorescence microscopy on different stiffness substrates provides useful information about primary cell morphology, cytoskeleton organization and vinculin containing focal adhesions as a function of substrate rigidity.

A protocol is described to extract primary human cells from surgical colon tumor and normal tissues. The isolated cells are then cultured on soft elastic substrates (polyacrylamide hydrogels) functionalized by an extracellular matrix protein, and embedded with fluorescent microbeads. Traction cytometry is performed to assess cellular contractile stresses.

从手术组织小学的人结肠癌细胞的分离和培养直接它们柔软的弹性基底牵引术

Cancer cells respond to matrix mechanical stiffness in a complex manner using a coordinated, hierarchical mechano-chemical system composed of adhesion ...

Sensitive Detection of Proteopathic Seeding Activity with FRET Flow Cytometry

Increasing evidence supports transcellular propagation of toxic protein aggregates, or proteopathic seeds, as a mechanism for the initiation and progression of pathology in several neurodegenerative diseases, including Alzheimer's disease and the related tauopathies. The potentially critical role of tau seeds in disease progression strongly supports the need for a sensitive assay that readily detects seeding activity in biological samples. 
By combining the specificity of fluorescence resonance energy transfer (FRET), the sensitivity of flow cytometry, and the stability of a monoclonal cell line, an ultra-sensitive seeding assay has been engineered and is compatible with seed detection from recombinant or biological samples, including human and mouse brain homogenates. The assay employs monoclonal HEK 293T cells that stably express the aggregation-prone repeat domain (RD) of tau harboring the disease-associated P301S mutation fused to either CFP or YFP, which produce a FRET signal upon protein aggregation. The uptake of proteopathic tau seeds (but not other proteins) into the biosensor cells stimulates aggregation of RD-CFP and RD-YFP, and flow cytometry sensitively and quantitatively monitors this aggregation-induced FRET. The assay detects femtomolar concentrations (monomer equivalent) of recombinant tau seeds, has a dynamic range spanning three orders of magnitude, and is compatible with brain homogenates from tauopathy transgenic mice and human tauopathy subjects. With slight modifications, the assay can also detect seeding activity of other proteopathic seeds, such as &#945;-synuclein, and is also compatible with primary neuronal cultures. The ease, sensitivity, and broad applicability of FRET flow cytometry makes it useful to study a wide range of protein aggregation disorders.

Cell-to-cell transfer of protein aggregates, or proteopathic seeds, may underlie the progression of pathology in neurodegenerative diseases. Here, a novel FRET flow cytometry assay is described that enables specific and sensitive detection of seeding activity from recombinant or biological samples.

与FRET流式细胞仪灵敏地检测Proteopathic播种活动

Increasing evidence supports transcellular propagation of toxic protein aggregates, or proteopathic seeds, as a mechanism for the initiation and ...

Microfluidic Flow Chambers Using Reconstituted Blood to Model Hemostasis and Platelet Transfusion In Vitro

Blood platelets prepared for transfusion gradually lose hemostatic function during storage. Platelet function can be investigated using a variety of (indirect) in vitro experiments, but none of these is as comprehensive as microfluidic flow chambers. In this protocol, the reconstitution of thrombocytopenic fresh blood with stored blood bank platelets is used to simulate platelet transfusion. Next, the reconstituted sample is perfused in microfluidic flow chambers which mimic hemostasis on exposed subendothelial matrix proteins. Effects of blood donation, transport, component separation, storage and pathogen inactivation can be measured in paired experimental designs. This allows reliable comparison of the impact every manipulation in blood component preparation has on hemostasis. Our results demonstrate the impact of temperature cycling, shear rates, platelet concentration and storage duration on platelet function. In conclusion, this protocol analyzes the function of blood bank platelets and this ultimately aids in optimization of the processing chain including phlebotomy, transport, component preparation, storage and transfusion.

Microfluidic Flow Chambers Using Reconstituted Blood to Model Hemostasis and Platelet Transfusion In Vitro

Platelet transfusion and hemostasis was modeled using blood reconstitution and microfluidic flow chambers to investigate the function of blood banking platelets. The data demonstrate the consequences of platelet storage lesion on hemostasis, in vitro.

微流体流钱伯斯再造使用血止血建模和血小板输注<em&gt;体外</em

Blood platelets prepared for transfusion gradually lose hemostatic function during storage. Platelet function can be investigated using a variety of ...

A Microfluidic Flow Chamber Model for Platelet Transfusion and Hemostasis Measures Platelet Deposition and Fibrin Formation in Real-time

Microfluidic models of hemostasis assess platelet function under conditions of hydrodynamic shear, but in the presence of anticoagulants, this analysis is restricted to platelet deposition only. The intricate relationship between Ca2+-dependent coagulation and platelet function requires careful and controlled recalcification of blood prior to analysis. Our setup uses a Y-shaped mixing channel, which supplies concentrated Ca2+/Mg2+ buffer to flowing blood just prior to perfusion, enabling rapid recalcification without sample stasis. A ten-fold difference in flow velocity between both reservoirs minimizes dilution. The recalcified blood is then perfused in a collagen-coated analysis chamber, and differential labeling permits real-time imaging of both platelet and fibrin deposition using fluorescence video microscopy. The system uses only commercially available tools, increasing the chances of standardization. Reconstitution of thrombocytopenic blood with platelets from banked concentrates furthermore models platelet transfusion, proving its use in this research domain. Exemplary data demonstrated that coagulation onset and fibrin deposition were linearly dependent on the platelet concentration, confirming the relationship between primary and secondary hemostasis in our model. In a timeframe of 16 perfusion min, contact activation did not take place, despite recalcification to normal Ca2+ and Mg2+ levels. When coagulation factor XIIa was inhibited by corn trypsin inhibitor, this time frame was even longer, indicating a considerable dynamic range in which the changes in the procoagulant nature of the platelets can be assessed. Co-immobilization of tissue factor with collagen significantly reduced the time to onset of coagulation, but not its rate. The option to study the tissue factor and/or the contact pathway increases the versatility and utility of the assay.

This paper describes an experimental model of hemostasis that simultaneously measures platelet function and coagulation. Platelet and fibrin fluorescence is measured in real-time, and platelet adhesion rate, coagulation rate, and onset of coagulation are determined. The model is used to determine platelet procoagulant properties under flow in concentrates for transfusion.

微流体流室模型血小板输注与止血措施，实时血小板沉积和纤维蛋白形成

Microfluidic models of hemostasis assess platelet function under conditions of hydrodynamic shear, but in the presence of anticoagulants, this analysis is ...

Detection of Endotoxin in Nano-formulations Using Limulus Amoebocyte Lysate (LAL) Assays

When present in pharmaceutical products, a Gram-negative bacterial cell wall component endotoxin (often also called lipopolysaccharide) can cause inflammation, fever, hypo- or hypertension, and, in extreme cases, can lead to tissue and organ damage that may become fatal. The amounts of endotoxin in pharmaceutical products, therefore, are strictly regulated. Among the methods available for endotoxin detection and quantification, the Limulus Amoebocyte Lysate (LAL) assay is commonly used worldwide. While any pharmaceutical product can interfere with the LAL assay, nano-formulations represent a particular challenge due to their complexity. The purpose of this paper is to provide a practical guide to researchers inexperienced in estimating endotoxins in engineered nanomaterials and nanoparticle-formulated drugs. Herein, practical recommendations for performing three LAL formats including turbidity, chromogenic and gel-clot assays are discussed. These assays can be used to determine endotoxin contamination in nanotechnology-based drug products, vaccines, and adjuvants.

Detection of Endotoxin in Nano-formulations Using Limulus Amoebocyte Lysate LAL Assays

Detection of endotoxins in engineered nanomaterials represents one of the grand challenges in the field of nanomedicine. Here, we present a case study that describes the framework composed of three different LAL formats to estimate potential endotoxin contamination in nanoparticles.

通过流式细胞术分离原代小鼠视网膜神经节细胞（RGC）

摘要

探索更多视频

此视频中的章节