这项工作由国家卫生研究院赠款资助:NS100624、DA013137、HD043680、MH106392 – T32 培训补助金 5T32GM081740

所有动物协议都经过南卡罗来纳大学动物护理和使用委员会的审查和批准。
1. 库存解决方案准备
<ol><li>解决方案 1 （1 L）: 到 900 mL 的去离子 H2O 添加 100 mL 的 10 倍磷酸盐缓冲盐水 （PBS） 和 2 mL 的 Triton X-100。</li>
	<li>解决方案 2 （1 L）: 至 900 mL 的去离子 H2O， 添加 100 mL 的 10 倍 PBS， 2mL 的 Tween-20 和 1 mL 的 10 毫克/mL 肝素库存解决方案。</li>
	<li>解决方案 3 （500 mL）: 至 400 mL 的解决方案 1，添加 11.5 克甘氨酸和 100 mL 二甲基硫化物 （DMSO）。</li>
	<li>解决方案 4 （50 mL）:要达到 42 mL 的解决方案 1，添加 3 mL 的相应血清和 5 mL 的 DMSO。</li>
	<li>初级抗体溶液 （50 mL）:要达到 46 mL 的解决方案 2，添加 2.5 mL 的 DMSO 和 1.5 mL 的相应血清。</li>
	<li>二级抗体溶液 （50 mL）:要达到 48.5 mL 的解决方案 2，添加 1.5 mL 的相应血清。 注:对于解决方案 4、初级溶液和二级溶液，请使用与二级抗体（例如山羊、马、牛）对应的血清。</li>
</ol>2. 样品制备
注:由于限制对 PFA 的暴露，请在烟雾罩中执行步骤 2.1 至 2.7。
<ol><li>使用 sevoflurane 对幼鼠（3-6 周）进行深度麻醉;当大鼠没有反应，对脚趾和尾巴捏没有反应时，继续到2.2。</li>
	<li>将老鼠放在一个超音位，用一把虹膜剪刀切开腹部壁。</li>
	<li>用梅奥剪刀切开肋骨笼底部，切到肋骨笼两侧的锁骨上。</li>
	<li>用下皮将胸骨和肋骨与心脏和肺部擦开。</li>
	<li>用23G针刺穿左心室，连接到灌注泵上，用虹膜剪刀切开右心房。</li>
	<li>用约 75 mL 的 100 mM （1x） PBS 进行跨心灌注。</li>
	<li>继续转心灌注，在 1x PBS 中缓冲约 100 mL 的 4% 半甲醛 （PFA）。</li>
	<li>用钳子把大脑从头骨上取下。</li>
	<li>将大脑置于下垂位置，然后使用剃须刀刀片和鼠脑矩阵切成4个相等部分（宽度约3毫米）。</li>
	<li>在密封的 5mL 塑料管中将每个部分在 1x PBS 中将每个部分在 4% PFA 中固定在摇床上，在 4 °C 处过夜。</li>
	<li>在室温下（RT）在摇床上将 4% PFA 固定在 1x PBS 中，持续固定 1 小时。</li>
	<li>在 RT 中用 1x PBS 清洗每个部分 30 分钟，3 次。</li>
</ol>3. 脱水和脱皮
<ol><li>在 RT 的 20% 甲醇/80% 去离子水溶液中孵育样品 1 小时。</li>
	<li>在 RT 的 40% 甲醇/60% 去离子水溶液中将样品孵育 1 小时。</li>
	<li>在 RT 的 60% 甲醇/40% 去离子水溶液中孵育样品 1 小时。</li>
	<li>在 RT 的 80% 甲醇/20% 去离子水溶液中将样品孵育 1 小时。</li>
	<li>在 Rt. 用超过 100% 甲醇重复 1 小时的 100% 甲醇孵化样品， 在 Rt 孵育 1 小时。</li>
	<li>将样品在 4° C 下 100% 甲醇中冷却约 10 分钟。</li>
	<li>准备 66% 二氯甲烷 （DCM）/33% 甲醇溶液。</li>
	<li>在 RT 的 DCM/甲醇溶液中将样品在一夜之间孵化，并进行摇晃。</li>
	<li>在 Rt 用甲醇清洗 30 分钟， 2 次。</li>
	<li>将样品在 4° C 下 100% 甲醇中冷却约 10 分钟。</li>
	<li>在 4° C 下，在甲醇中冷冻、新鲜制备的 5% 过氧化氢中漂白过夜。</li>
	<li>在 RT 的 80% 甲醇/20% 去离子水溶液中将样品孵育 1 小时。</li>
	<li>在 RT 的 60% 甲醇/40% 去离子水溶液中孵育样品 1 小时。</li>
	<li>在 RT 的 40% 甲醇/60% 去离子水溶液中将样品孵育 1 小时。</li>
	<li>在 RT 的 20% 甲醇/80% 去离子水溶液中孵育样品 1 小时。</li>
	<li>在 RT 将样品在 1x PBS 中孵育 1 小时。</li>
	<li>在 RT 中将溶液 1 洗涤 1 小时，2 次。</li>
</ol>4. 霍乱毒素子字组 B 标签
<ol><li>将 1 mL 注射器的针尖插入原子核累积位点。</li>
	<li>慢慢注射 2.5 μL 的 1% 生物素 CTB 超过 20 秒。</li>
	<li>将针尖留在原位 1 分钟，然后缓慢取出超过 10 秒，以防止泄漏。</li>
</ol>5. 抗体应用
<ol><li>在水浴中将样品在 37 °C 下在解决方案 3 中孵育 2 天。</li>
	<li>在水浴中将样品在溶液 4 中孵育 2 天，在 37 °C 下。</li>
	<li>在水浴中用原性抗体在 37 °C 下孵育 7 天。</li>
	<li>在解决方案 2 中清洗 5 次，每次洗涤孵育 1 小时。在 Rt 过夜存储解决方案 2 。</li>
	<li>在水浴中37°C下用二次抗体孵育7天。</li>
	<li>在解决方案 2 中清洗 5 次，每次洗涤孵化 1 小时;在 Rt 过夜的解决方案 2 中存储。 注:从 5.6 开始的所有步骤，包括最终存储，应在低光下进行。样品管可以用铝箔屏蔽。本协议中用于抗体的浓度为:TH在1:100，Iba1在1:200，二级抗体在1:100。在步骤 5.1-5.6 中添加额外的解决方案 2，以确保管子完全充满。</li>
</ol>6. 组织清除
<ol><li>在 RT 的 20% 甲醇/80% 去离子水溶液中孵育样品 1 小时。</li>
	<li>在 RT 的 40% 甲醇/60% 去离子水溶液中将样品孵育 1 小时。</li>
	<li>在 RT 的 60% 甲醇/40% 去离子水溶液中孵育样品 1 小时。</li>
	<li>在 RT 的 80% 甲醇/20% 去离子水溶液中将样品孵育 1 小时。</li>
	<li>在 RT 将样品在 100% 甲醇中孵育 1 小时。</li>
	<li>在 Rt 过夜孵育新鲜 100% 甲醇。</li>
	<li>在室温下以 66% DCM/33% 甲醇孵育 3 小时，并具有抖动。</li>
	<li>在二苯醚 （DBE） 中孵育，无需摇晃。将样品留在 DBE 中直到清除，并存储在 DBE 中直到成像。</li>
</ol>7. 安装
<ol><li>获取由 Visijet M3 水晶树脂制成的 3D 打印室（idisco.info 网站上提供模板）。</li>
	<li>使用环氧树脂将腔室固定在显微镜滑动器上。</li>
	<li>将样品放在房间中间的方形空间中。</li>
	<li>将房间完全填充 DBE。</li>
	<li>将 0.17 毫米厚的盖唇放在腔室上并施加压力，直到盖唇与腔室墙壁完全接触。</li>
	<li>使用环氧树脂将盖唇边缘密封到腔室。</li>
	<li>旋转腔室，让气泡从填充入口中逸出。</li>
	<li>给会议厅加满额外的 DBE。</li>
	<li>用环氧树脂密封灌装入口，并允许治愈。 注意:在安装过程中，多余的 DBE 会溢出。</li>
</ol>8. 成像
<ol><li>使用共聚焦显微镜系统进行 4 倍放大的 z 扫描（参见所附 的 3D 视频）。</li>
	<li>使用激光设置以类似于二级抗体指定的波长的波长发出样品的荧光激发。利用 HeNe 激光集以 632 nm 的速度发射，实现了 TH 激发。</li>
	<li>将探测器设置为接近激光发射的波长。对于当前协议，TH 探测器设置为 650 nm。</li>
	<li>提高探测器的增益，直到有可见信号。图像的 650LP 增益设置为 7.50 B。</li>
	<li>使用共聚焦成像软件中的 扫描 选项，移动显微镜阶段，直到样品成为焦点。</li>
	<li>在所有平原的组织周围导航，并使用共焦成像软件获取单个图像或 z 堆栈图像。</li>
	<li>成像完成后，将样品从腔室中取出。将其放回完全充满 DBE 的管子中，并存放在 RT 的黑暗地方，最好用铝箔覆盖。 注:只要荧光信号仍然强烈，样品就可以重新安装并成像。</li>
</ol>

<ol>
	<li>Chung, 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=Structural+and+molecular+interrogation+of+intact+biological+systems.">Structural and molecular interrogation of intact biological systems.</a> Nature. 497 (7449), 332-337 (2013).</li><li>Susaki, E. 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=Whole-brain+imaging+with+single-cell+resolution+using+chemical+cocktails+and+computational+analysis.">Whole-brain imaging with single-cell resolution using chemical cocktails and computational analysis.</a> Cell. 157 (3), 726-739 (2014).</li><li>Ueda, H. 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=Tissue+clearing+and+its+applications+in+neuroscience.">Tissue clearing and its applications in neuroscience.</a> Nature Reviews Neuroscienc. 21, 298 (2020).</li><li>Renier, N., 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=iDISCO:+a+simple,+rapid+method+to+immunolabel+large+tissue+samples+for+volume+imaging.">iDISCO: a simple, rapid method to immunolabel large tissue samples for volume imaging.</a> Cell. 159 (4), 896-910 (2014).</li><li>Renier, N., 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=Mapping+of+brain+activity+by+automated+volume+analysis+of+immediate+early+genes.">Mapping of brain activity by automated volume analysis of immediate early genes.</a> Cell. 165 (7), 1789-1802 (2016).</li><li>Reid, W., 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=An+HIV-1+transgenic+rat+that+develops+HIV-related+pathology+and+immunologic+dysfunction.">An HIV-1 transgenic rat that develops HIV-related pathology and immunologic dysfunction.</a> Proceedings of the National Academy of Science U. S. A. 98, 9271-9276 (2001).</li><li>Vigorito, M., Connaghan, K. P., Chang, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+HIV-1+transgenic+rat+model+of+neuroHIV.">The HIV-1 transgenic rat model of neuroHIV.</a> Brain, Behavior, and Immunity. 48, 336-349 (2015).</li><li>McLaurin, K. 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=Synaptic+connectivity+in+medium+spiny+neurons+of+the+nucleus+accumbens:+A+sex-dependent+mechanism+underlying+apathy+in+the+HIV-1+transgenic+rat.">Synaptic connectivity in medium spiny neurons of the nucleus accumbens: A sex-dependent mechanism underlying apathy in the HIV-1 transgenic rat.</a> Frontiers in Behavior Neurosciences. 12, 285 (2018).</li><li>Fitting, S., Booze, R. M., Mactutus, C. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=HIV-1+proteins,+Tat+and+gp120,+target+the+developing+dopamine+system.">HIV-1 proteins, Tat and gp120, target the developing dopamine system.</a> Current HIV Research. 13, 135-137 (2015).</li><li>Javadi-Paydar, M., Roscoe, R. F., Denton, A. R., Mactutus, C. F., Booze, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=HIV-1+and+cocaine+disrupt+dopamine+reuptake+and+medium+spiny+neurons+in+female+rat+striatum.">HIV-1 and cocaine disrupt dopamine reuptake and medium spiny neurons in female rat striatum.</a> PLos One. 12 (11), 0188404 (2017).</li><li>Bertrand, S. J., Mactutus, C. F., Harrod, S. B., Moran, L. M., Booze, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=HIV-1+proteins+dysregulate+motivational+processes+and+dopamine+circuitry.">HIV-1 proteins dysregulate motivational processes and dopamine circuitry.</a> Science Report. 8, 6152 (2018).</li><li>Denton, A. 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=Selective+monoaminergic+and+histaminergic+circuit+dysregulation+following+long-term+HIV-1+protein+exposure.">Selective monoaminergic and histaminergic circuit dysregulation following long-term HIV-1 protein exposure.</a> Journal of neurovirology. 25 (4), 540-550 (2019).</li><li>Berendse, H. W., Groenewegen, H. J., Lohman, A. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Compartmental+distribution+of+ventral+striatal+neurons+projecting+to+the+mesencephalon+in+the+rat.">Compartmental distribution of ventral striatal neurons projecting to the mesencephalon in the rat.</a> Journal of Neuroscienc. 12 (6), 2079-2103 (1992).</li><li>Peyron, C., Petit, J. M., Rampon, C., Jouvet, M., Luppi, P. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Forebrain+afferents+to+the+rat+dorsal+raphe+nucleus+demonstrated+by+retrograde+and+anterograde+tracing+methods.">Forebrain afferents to the rat dorsal raphe nucleus demonstrated by retrograde and anterograde tracing methods.</a> Neuroscience. 82 (2), 443-468 (1998).</li><li>Barrot, 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=Braking+dopamine+systems:+a+new+GABA+master+structure+for+mesolimbic+and+nigrostriatal+functions.">Braking dopamine systems: a new GABA master structure for mesolimbic and nigrostriatal functions.</a> The Journal of Neuroscience: The Official Journal of the Society for Neuroscienc. 32 (41), 14094-14101 (2012).</li><li>Roostalu, U., 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+whole-brain+3D+imaging+of+tyrosine+hydroxylase-labeled+neuron+architecture+in+the+mouse+MPTP+model+of+Parkinson's+disease.">Quantitative whole-brain 3D imaging of tyrosine hydroxylase-labeled neuron architecture in the mouse MPTP model of Parkinson's disease.</a> Disease Models &amp; Mechanisms. 12 (11), (2019).</li><li>Ransohoff, R., Cardona, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+myeloid+cells+of+the+central+nervous+system+parenchyma.">The myeloid cells of the central nervous system parenchyma.</a> Nature. 468, 253-262 (2010).</li><li>Rocha, M. D., 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=Tissue+Clearing+and+Light+Sheet+Microscopy:+Imaging+the+Unsectioned+Adult+Zebra+Finch+Brain+at+Cellular+Resolution.">Tissue Clearing and Light Sheet Microscopy: Imaging the Unsectioned Adult Zebra Finch Brain at Cellular Resolution.</a> Frontiers in Neuroanatomy. 13, 13 (2019).</li><li>Richardson, D. S., Lichtman, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clarifying+tissue+clearing.">Clarifying tissue clearing.</a> Cell. 162 (2), 246-257 (2015).</li></ol>

作者没有利益冲突要申报。

组织清除为传统 IHC 协议的局限性提供了解决方案。透明的样品可最大限度地减少光的散射和吸收，从而提供细胞水平的光学访问到完整的组织18，19。组织清除技术通过脱毛、去装饰和贴花与溶剂的管理使组织透明化。一旦组织样本的折射指数与所选成像介质的折射索引匹配，样本将呈现完全透明，并可以正确成像3。目前的疏水方案?...

一些组织清除技术已被验证用于大脑:水凝胶，亲水性和疏水性。这些技术旨在通过溶剂的管理，通过脱毛、去装饰和贴花来使组织透明化。一旦组织样本的折射指数与所选成像介质的折射指数匹配，就可以获得样本的清晰图像。水凝胶技术，如 CLARITY，通过将生物分子与丙烯酸酯水凝胶连接起来，确保组织中的生物分子的安全，从而防止结构损伤和蛋白质损失1.然而，水凝胶技术使用的苛刻化学物质比有可能损害更脆弱的组织，更密集的组织样本可能不符合水凝胶协议。某些水凝胶技术可能需要昂贵的设备或导致组织扩张。亲水技术，如立方体，通过在组织2内形成氢键来保存3D结构。组织扩张也可能发生在某些亲水协议中。亲水技术的清除能力往往与疏水技术的能力不相称，这对更稠密、更厚的组织非常重要。
疏水技术通常速度快，不需要特殊设备，并产生易于处理和存储的样品。iDISCO 是一种疏水技术，可消除其他疏水协议中可能发生的收缩。最初，DISCO组织清除技术是由Renier等人描述的 ，用于小鼠的胚胎和密集的成人器官。该技术在初始脱水步骤中去除组织中的水，从而减少光散射。组织在预处理过程中渗透，允许深层抗体渗透。远红光谱中的亚历克萨氟染料用于免疫标签，以避免组织在低波长5的自身发光。经过疏水清除协议的组织能够轻松处理，并且由于 Alexa 氟染料的寿命长，可以成像几次。如果储存得当，组织可以在初始处理后提供数月到一年的图像。
在本协议中，酪氨酸羟基酶（TH）抗体、Iba1抗体和霍乱毒素亚细胞B（CTB）用于男性和女性控制以及HIV-1转基因（Tg）大鼠大脑。HIV-1 Tg大鼠拥有构成HIV-1病毒基因组的9个基因中的7个，这导致了长期HIV-1蛋白暴露的非传染性模型6，7，8。多巴胺变种以前在HIV-1 Tg大鼠身上已经证明，HIV-1本身是一种炎症性疾病，所以抗体选择与实验设计9，10，11，12有关。CTB是一种通过结核结合附着在神经元的示踪器，可用于追踪大脑中令人不关心的投影。CTB以前曾被用来研究从细胞核到亚斯坦蒂娅黑鬼区域的投影，大脑的两个区域严重涉及多巴胺性通路13、14、15。
在此协议中，TH 将作为多巴胺生产的标志，Iba1 将标记激活的微胶质。TH 抗体使用选择性地标记单个带在大约 62 kDa，对应酪氨酸羟基酶。Iba1 抗体对应于 Iba1 卡盒终端序列。这两种抗体都是在兔子身上培养的，是多克隆的。CTB 将用于逆行追踪神经元从细胞核区到亚斯坦蒂娅黑鬼区域。当前协议还以两种不同的方式为原 iDISCO 协议的调整提供了指导:1） 通过更改阻塞步骤中的血清试剂来全面减少背景染色，2） 扩大孵化时间以适合较大的组织样本。总体而言，本协议提供了持续的证据，证明疏水清除技术在大鼠的脑组织中是可行的，与HIV-1病毒蛋白没有明显的有害相互作用，并且与TH抗体、Iba1抗体和CTB相容。

<table>
	<tbody>
		<tr>
			<td>Cholera Toxin Subunit B (Recombinant), Alexa Fluor 488</td>
			<td>Invitrogen</td>
			<td>C34775</td>
			<td></td>
		</tr>
		<tr>
			<td>DBE</td>
			<td>Sigma-Aldrich</td>
			<td>108014-1KG</td>
			<td></td>
		</tr>
		<tr>
			<td>DCM</td>
			<td>Sigma-Aldrich</td>
			<td>270997-100mL</td>
			<td></td>
		</tr>
		<tr>
			<td>DMSO</td>
			<td>Sigma-Aldrich</td>
			<td>472301-1L</td>
			<td></td>
		</tr>
		<tr>
			<td>Glycine</td>
			<td>Fisher Chemical</td>
			<td>G46-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti-rabbit Alexa Fluor Plus 647</td>
			<td>Invitrogen</td>
			<td>A32733</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat serum</td>
			<td>Sigma Life Science</td>
			<td>G9023-10mL</td>
			<td></td>
		</tr>
		<tr>
			<td>Heparin</td>
			<td>Acros Organics</td>
			<td>41121-0010</td>
			<td></td>
		</tr>
		<tr>
			<td>Iba1 primary antibody</td>
			<td>FUJIFILM Wako</td>
			<td>019-19741</td>
			<td></td>
		</tr>
		<tr>
			<td>Kwik-sil epoxy</td>
			<td>VWR</td>
			<td>70730-062</td>
			<td></td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>Sigma-Aldrich</td>
			<td>34860-1l-R</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS</td>
			<td>Fisher Bioreagents</td>
			<td>BP2944-100</td>
			<td></td>
		</tr>
		<tr>
			<td>Perfusion machine</td>
			<td>VWR</td>
			<td>70730-062</td>
			<td>mini pump variable flow</td>
		</tr>
		<tr>
			<td>PFA</td>
			<td>Sigma-Aldrich</td>
			<td>158127-3KG</td>
			<td></td>
		</tr>
		<tr>
			<td>TH primary antibody</td>
			<td>Millipore Sigma</td>
			<td>AB152</td>
			<td></td>
		</tr>
		<tr>
			<td>TritonX-100</td>
			<td>Fisher Bioreagents</td>
			<td>BP151-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Tween-20</td>
			<td>Fisher Bioreagents</td>
			<td>BP337-500</td>
			<td></td>
		</tr>
	</tbody>
</table>

a hydrophobic tissue clearing method for rat brain tissue

疏水组织清除方法易于调节、快速和低成本的程序，允许研究未受变组织样本中感兴趣的分子。传统的免疫标签程序要求将样品切成薄部分，这限制了标记和检查完整结构的能力。但是，如果脑组织在处理过程中能够保持完整，则结构和回路可以保持完好无损进行分析。先前建立的清除方法需要大量时间才能完全清除组织，而苛刻的化学物质通常会损害敏感的抗体。iDISCO 方法快速、完全地清除组织，与许多抗体兼容，无需特殊的实验室设备。这项技术最初被验证用于小鼠组织，但目前的协议使这种方法适应了控制半球和转基因大鼠大脑的图像。除此之外，本协议还对预先存在的协议进行了若干调整，以提供更清晰的图像，减少背景污渍。使用目前的疏水组织清除方法，在HIV-1转基因大鼠和F344/N控制大鼠中验证了Iba-1和酪氨酸羟基酶的抗体。大脑是一个交织在一起的网络，结构相互作用的频率高于彼此的相互作用。分析整个系统的大脑，而不是单个片段的组合，是整个大脑清理方法的最大好处。

利用这种经过修改的疏水组织清除方案，实现了F344/N和HIV-1大鼠脑组织的大面积完全清除。 图1 显示了在亚斯坦蒂娅尼格拉区域TH的典型共聚焦图像。 图 1A 表示密集、正色。通过"Z"平面聚焦以确认正染色和适当的细胞形态，可以分析出像这样的密集区域。 图1B 表示稀疏的正染色，可以通过TH神经元独特的形态来识别。 <strong class="...

Watch this Scientific Journal Video about A Hydrophobic Tissue Clearing Method for Rat Brain Tissue at JoVE.com

A Hydrophobic Tissue Clearing Method for Rat Brain Tissue

在这里，我们提出了一个疏水组织清除方法，允许查看目标分子作为完整的大脑结构的一部分。这项技术现已得到F344/N控制和艾滋病毒-1转基因两性大鼠的验证。

鼠脑组织疏水组织清除方法

Hydrophobic tissue clearing methods are easily adjustable, fast, and low-cost procedures that allows for the study of a molecule of interest in unaltered ...

a-hydrophobic-tissue-clearing-method-for-rat-brain-tissue

Research

JoVE Journal

Neuroscience

3.8K 次观看.  University of South Carolina. 在这里，我们提出了一个疏水组织清除方法，允许查看目标分子作为完整的大脑结构的一部分。这项技术现已得到F344/N控制和艾滋病毒-1转基因两性大鼠的验证。

视频: A Hydrophobic Tissue Clearing Method for Rat Brain Tissue

Intact Histological Characterization of Brain-implanted Microdevices and Surrounding Tissue

Research into the design and utilization of brain-implanted microdevices, such as microelectrode arrays, aims to produce clinically relevant devices that interface chronically with surrounding brain tissue. Tissue surrounding these implants is thought to react to the presence of the devices over time, which includes the formation of an insulating "glial scar" around the devices. However, histological analysis of these tissue changes is typically performed after explanting the device, in a process that can disrupt the morphology of the tissue of interest.
Here we demonstrate a protocol in which cortical-implanted devices are collected intact in surrounding rodent brain tissue. We describe how, once perfused with fixative, brains are removed and sliced in such a way as to avoid explanting devices. We outline fluorescent antibody labeling and optical clearing methods useful for producing an informative, yet thick tissue section. Finally, we demonstrate the mounting and imaging of these tissue sections in order to investigate the biological interface around brain-implanted devices.

Here we present a histological method for capturing, labeling, optically clearing, and imaging the intact brain tissue interface around chronically implanted microdevices in rodent brain tissue. Results from the techniques comprising this method are useful for understanding the impact of various penetrating brain-implants on their surrounding tissue.

脑植入的微型器件及周围组织的完整的组织学特性研究

Research  into the design and utilization of brain-implanted microdevices, such as  microelectrode arrays, aims to produce clinically relevant devices ...

科研

神经科学

Immunohistochemical Analysis in the Rat Central Nervous System and Peripheral Lymph Node Tissue Sections

Immunohistochemistry (IHC) provides highly specific, reliable and attractive protein visualization. Correct performance and interpretation of an IHC-based multicolor labeling is challenging, especially when utilized for assessing interrelations between target proteins in the tissue with a high fat content such as the central nervous system (CNS).
Our protocol represents a refinement of the standard immunolabeling technique particularly adjusted for detection of both structural and soluble proteins in the rat CNS and peripheral lymph nodes (LN) affected by neuroinflammation. Nonetheless, with or without further modifications, our protocol could likely be used for detection of other related protein targets, even in other organs and species than here presented.

We here present an optimized, detailed protocol for double immunostaining in formalin-fixed, paraffin-embedded rat central nervous system (CNS) and peripheral lymph node (LN) tissue sections.

免疫组化分析大鼠中枢神经系统和周围淋巴结组织切片

Immunohistochemistry (IHC) provides highly specific, reliable and attractive protein visualization. Correct performance and interpretation of an IHC-based ...

Primer for Immunohistochemistry on Cryosectioned Rat Brain Tissue: Example Staining for Microglia and Neurons

Immunohistochemistry is a widely used technique for detecting the presence, location, and relative abundance of antigens in situ. This introductory level protocol describes the reagents, equipment, and techniques required to complete immunohistochemical staining of rodent brain tissue, using markers for microglia and neuronal elements as an example. Specifically, this paper is a step-by-step protocol for fluorescent visualization of microglia and neurons via immunohistochemistry for Iba1 and Pan-neuronal, respectively. Fluorescence double-labeling is particularly useful for the localization of multiple proteins within the same sample, providing the opportunity to accurately observe interactions between cell types, receptors, ligands, and/or the extracellular matrix in relation to one another as well as protein co-localization within a single cell. Unlike other visualization techniques, fluorescence immunohistochemistry staining intensity may decrease in the weeks to months following staining, unless appropriate precautions are taken. Despite this limitation, in many applications fluorescence double-labeling is preferred over alternatives such as 3,3&#39;-diaminobenzidine tetrahydrochloride (DAB) or alkaline phosphatase (AP), as fluorescence is more time efficient and allows for more precise differentiation between two or more markers. The discussion includes troubleshooting tips and advice to promote success.

This introductory level protocol describes the reagents, equipment, and techniques required to complete immunohistochemical staining of rodent brains, using markers for microglia and neuronal elements as an example.

引物对免疫冰冻切片大鼠脑组织:例为染色小胶质细胞和神经元

Immunohistochemistry is a widely used technique for detecting the presence, location, and relative abundance of antigens in situ. This introductory level ...

Using Fluorescence Activated Cell Sorting to Examine Cell-Type-Specific Gene Expression in Rat Brain Tissue

The brain is comprised of four primary cell types including neurons, astrocytes, microglia and oligodendrocytes. Though they are not the most abundant cell type in the brain, neurons are the most widely studied of these cell types given their direct role in impacting behaviors. Other cell types in the brain also impact neuronal function and behavior via the signaling molecules they produce. Neuroscientists must understand the interactions between the cell types in the brain to better understand how these interactions impact neural function and disease. To date, the most common method of analyzing protein or gene expression utilizes the homogenization of whole tissue samples, usually with blood, and without regard for cell type. This approach is an informative approach for examining general changes in gene or protein expression that may influence neural function and behavior; however, this method of analysis does not lend itself to a greater understanding of cell-type-specific gene expression and the effect of cell-to-cell communication on neural function. Analysis of behavioral epigenetics has been an area of growing focus which examines how modifications of the deoxyribonucleic acid (DNA) structure impact long-term gene expression and behavior; however, this information may only be relevant if analyzed in a cell-type-specific manner given the differential lineage and thus epigenetic markers that may be present on certain genes of individual neural cell types. The Fluorescence Activated Cell Sorting (FACS) technique described below provides a simple and effective way to isolate individual neural cells for the subsequent analysis of gene expression, protein expression, or epigenetic modifications of DNA. This technique can also be modified to isolate more specific neural cell types in the brain for subsequent cell-type-specific analysis.

The goal of this protocol is to use the fluorescence activated cell sorting (FACS) technique to sort specific types of neural cells for subsequent analysis of cell-type-specific gene expression, epigenetic markers, and or protein expression.

在大鼠脑组织用荧光活化细胞分选，以检查细胞类型特异性基因表达

The brain is comprised of four primary cell types including neurons, astrocytes, microglia and oligodendrocytes. Though they are not the most abundant ...

Sublimation of DAN Matrix for the Detection and Visualization of Gangliosides in Rat Brain Tissue for MALDI Imaging Mass Spectrometry

Sample preparation is key for optimal detection and visualization of analytes in Matrix-assisted Laser Desorption/Ionization (MALDI) Imaging Mass Spectrometry (IMS) experiments. Determining the appropriate protocol to follow throughout the sample preparation process can be difficult as each step must be optimized to comply with the unique characteristics of the analytes of interest. This process involves not only finding a compatible matrix that can desorb and ionize the molecules of interest efficiently, but also selecting the appropriate matrix deposition technique. For example, a wet matrix deposition technique, which entails dissolving a matrix in solvent, is superior for desorption of most proteins and peptides, whereas dry matrix deposition techniques are particularly effective for ionization of lipids. Sublimation has been reported as a highly efficient method of dry matrix deposition for the detection of lipids in tissue by MALDI IMS due to the homogeneity of matrix crystal deposition and minimal analyte delocalization as compared to many wet deposition methods 1,2. Broadly, it involves placing a sample and powdered matrix in a vacuum-sealed chamber with the samples pressed against a cold surface. The apparatus is then lowered into a heated bath (sand or oil), resulting in sublimation of the powdered matrix onto the cooled tissue sample surface. Here we describe a sublimation protocol using 1,5-diaminonaphthalene (DAN) matrix for the detection and visualization of gangliosides in the rat brain using MALDI IMS.

A protocol for the sublimation of DAN matrix onto rat brain tissue for the detection of gangliosides using MALDI Imaging Mass Spectrometry is presented.

DAN矩阵升华为神经节苷脂对大鼠脑组织的检测和可视化MALDI成像质谱

Sample preparation is key for optimal detection and visualization of analytes in Matrix-assisted Laser Desorption/Ionization (MALDI) Imaging Mass ...

A Rat Model of Mild Intrauterine Hypoperfusion with Microcoil Stenosis

Intrauterine hypoperfusion/ischemia is one of the major causes of intrauterine/fetal growth restriction, preterm birth, and low birth weight. Most studies of this phenomenon have been performed in either models with severe intrauterine ischemia or models with gradient degree of intrauterine hypoperfusion. No study has been performed in a model on uniform mild intrauterine hypoperfusion (MIUH). Two models have been used for studies of MIUH: a model based on suture ligation of either side of the arterial arcade formed with the uterine and ovarian arteries, and a transient model based on clipping the bilateral ovarian arteries and aorta having patency. Those two rodent models of MIUH have some limitations, e.g., not all fetuses are subjected to MIUH, depending on their position in the uterine horn. In our MIUH model, all fetuses are subjected to a comparable level of intrauterine hypoperfusion. MIUH was achieved by mild stenosis of all four arteries feeding the uterus, i.e., the bilateral uterine and ovarian arteries.
Arterial stenosis was induced by metal microcoils wrapped around the feeding arteries. Producing arterial stenosis with microcoils allowed us to control, optimize, and reproduce decreased blood flow with very little inter-animal variability and a low mortality rate, thus enabling accurate evaluation. When microcoils with an inner diameter of 0.24 mm were used, the blood flow in both the placenta and fetus was mildly decreased (approximately 30% from the pre-stenosis level in the placenta). The offspring of our MIUH model clearly demonstrates long-lasting alterations in neurological, neuroanatomical and behavioral test results.

Mild intrauterine hypoperfusion was produced by artery stenosis with metal microcoils wrapped around the uterine and ovarian arteries in rats at embryonic day 17. This procedure produced prenatal hypoperfusion and intrauterine growth restriction.

轻度宫内灌注圈狭窄的大鼠模型

Intrauterine hypoperfusion/ischemia is one of the major causes of intrauterine/fetal growth restriction, preterm birth, and low birth weight. Most studies ...

Novel Passive Clearing Methods for the Rapid Production of Optical Transparency in Whole CNS Tissue

Since the development of CLARITY, a bioelectrochemical clearing technique that allows for three-dimensional phenotype mapping within transparent tissues, a multitude of novel clearing methodologies including CUBIC (clear, unobstructed brain imaging cocktails and computational analysis), SWITCH (system-wide control of interaction time and kinetics of chemicals), MAP (magnified analysis of the proteome), and PACT (passive clarity technique), have been established to further expand the existing toolkit for the microscopic analysis of biological tissues. The present study aims to improve upon and optimize the original PACT procedure for an array of intact rodent tissues, including the whole central nervous system (CNS), kidneys, spleen, and whole mouse embryos. Termed psPACT (process-separate PACT) and mPACT (modified PACT), these novel techniques provide highly efficacious means of mapping cell circuitry and visualizing subcellular structures in intact normal and pathological tissues. In the following protocol, we provide a detailed, step-by-step outline on how to achieve maximal tissue clearance with minimal invasion of their structural integrity via psPACT and mPACT.

Here, we present two novel methodologies, psPACT and mPACT, for achieving maximal optical transparency and subsequent microscopic analysis of tissue vasculature in the intact rodent whole CNS.

一种新的用于全中枢神经系统光透明快速生成的无源清除方法

Since the development of CLARITY, a bioelectrochemical clearing technique that allows for three-dimensional phenotype mapping within transparent tissues, ...

Isolation of Cerebral Capillaries from Fresh Human Brain Tissue

Understanding blood-brain barrier function under physiological and pathophysiological conditions is critical for the development of new therapeutic strategies that hold the promise to enhance brain drug delivery, improve brain protection, and treat brain disorders. However, studying the human blood-brain barrier function is challenging. Thus, there is a critical need for appropriate models. In this regard, brain capillaries isolated from human brain tissue represent a unique tool to study barrier function as close to the human in vivo situation as possible. Here, we describe an optimized protocol to isolate capillaries from human brain tissue at a high yield and with consistent quality and purity. Capillaries are isolated from fresh human brain tissue using mechanical homogenization, density-gradient centrifugation, and filtration. After the isolation, the human brain capillaries can be used for various applications including leakage assays, live cell imaging, and immune-based assays to study protein expression and function, enzyme activity, or intracellular signaling. Isolated human brain capillaries are a unique model to elucidate the regulation of the human blood-brain barrier function. This model can provide insights into central nervous system (CNS) pathogenesis, which will help the development of therapeutic strategies for treating CNS disorders.

Isolated brain capillaries from human brain tissue can be used as a preclinical model to study barrier function under physiological and pathophysiological conditions. Here, we present an optimized protocol to isolate brain capillaries from fresh human brain tissue.

新鲜人脑组织中毛细血管的分离

Understanding blood-brain barrier function under physiological and pathophysiological conditions is critical for the development of new therapeutic ...

Preparation of Newborn Rat Brain Tissue for Ultrastructural Morphometric Analysis of Synaptic Vesicle Distribution at Nerve Terminals

Our laboratory and many others have exploited the high resolving power of transmission electron microscopy to study the morphology and spatial organization of synaptic vesicles. In order to obtain high-quality electron micrographs that can yield the degree of morphological detail necessary for quantitative analysis of pre-synaptic vesicle distribution, optimal specimen preparation is critical. Chemical fixation is the first step in the process of specimen preparation, and of utmost importance to preserve fine ultrastructure. Vascular fixation with a glutaraldehyde-formaldehyde solution, followed by treatment of vibratome-sectioned specimens with osmium tetroxide, stabilizes the maximum number of molecules, especially proteins and lipids, and results in superior conservation of ultrastructure. Tissue is then processed with counterstaining, sequential dehydration and resin-embedding. En bloc staining with uranyl acetate (i.e., staining of vibratome-sectioned tissue before resin embedding) enhances endogenous contrast and stabilizes cell components against extraction during specimen processing. Contrast can be further increased by applying uranyl acetate as a post-stain on ultrathin sections. Double-staining of ultrathin sections with lead citrate after uranyl acetate treatment also improves image resolution, by intensifying electron-opacity of nucleic acid-containing structures through selective binding of lead to uranyl acetate. Transmission electron microscopy is a powerful tool for characterization of the morphological details of synaptic vesicles and quantification of their size and spatial organization in the terminal bouton. However, because it uses fixed tissue, transmission electron microscopy can only provide indirect information regarding living or evolving processes. Therefore, other techniques should be considered when the main objective is to study dynamic or functional aspects of synaptic vesicle trafficking and exocytosis.

We describe procedures for processing newborn rat brain tissue to obtain high-resolution electron micrographs for morphometric analysis of synaptic vesicle distribution at nerve terminals. The micrographs obtained with these methods can also be used to study the morphology of a number of other cellular components and their dimensional structural relationships.

新生大鼠脑组织在神经端子突形圆锥花序分布超微结构形态分析中的制备

Our laboratory and many others have exploited the high resolving power of transmission electron microscopy to study the morphology and spatial ...

Immunostaining of Whole-Mount Retinas with the CLARITY Tissue Clearing Method

The tissue hydrogel delipidation method (CLARITY), originally developed by the Deisseroth laboratory, has been modified and widely used for immunostaining and imaging of thick brain samples. However, this advanced technology has not yet been used for whole-mount retinas. Although the retina is partially transparent, its thickness of approximately 200 &#181;m (in mice) still limits the penetration of antibodies into the deep tissue as well as reducing light penetration for high-resolution imaging. Here, we adapted the CLARITY method for whole-mount mouse retinas by polymerizing them with an acrylamide monomer to form a nanoporous hydrogel and then clearing them in sodium dodecyl sulfate to minimize protein loss and avoid tissue damage. CLARITY-processed retinas were immunostained with antibodies for retinal neurons, glial cells, and synaptic proteins, mounted in a refractive index matching solution, and imaged. Our data demonstrate that CLARITY&#160;can improve the quality of standard immunohistochemical staining and imaging for retinal neurons and glial cells in whole-mount preparation. For instance, 3D resolution of fine axon-like and dendritic structures of dopaminergic amacrine cells were much improved by CLARITY. Compared to non-processed whole-mount retinas, CLARITY can reveal immunostaining for synaptic proteins such as postsynaptic density protein 95. Our results show that CLARITY renders the retina more optically transparent after the removal of lipids and preserves fine structures of retinal neurons and their proteins, which can be routinely used for obtaining high-resolution imaging of retinal neurons and their subcellular structures in whole-mount preparation.

Here we present a protocol to adapt the CLARITY method of the brain tissues for whole-mount retinas to improve the quality of standard immunohistochemical staining and high-resolution imaging of retinal neurons and their subcellular structures.

使用清晰组织清除方法对全山视网膜进行免疫染色

The tissue hydrogel delipidation method (CLARITY), originally developed by the Deisseroth laboratory, has been modified and widely used for immunostaining ...