这项工作得到了补助金1K25MH089851，1P01DA028555 - 01A1，2R01 NS034239，2R37 NS36126，P01 NS31492，P20RR 15635，P01MH64570，并从美国国立卫生研究院P01 NS43985。作者感谢罗宾泰勒女士的手稿和杰出的图形和文学支持的关键读。作者还要感谢他们的技术支持，梅丽莎 - 梅隆埃林麦金太尔和Lindsay米。

1。简介选择性的活动性疾病的和持续的微生物感染的细胞和组织的网站提供的药物和治疗大分子（多肽，蛋白质和核酸）将提高1-3在疾病的药品反应。网站是一个特定的细胞巨噬细胞是高度流动和免疫从事的主要目标是一致的人类免疫缺陷病毒（HIV）。，重要的是，巨噬细胞参与炎症也退行性，炎症，感染性的疾病，包括范围广泛的基础和癌变的疾病和细胞的流动性疾病的网站背后的组织损伤5-9进展。更重要的是，使用药物，高分子和信号运营商的血源性巨噬细胞，其翻译的潜力已经获得了最近受到关注。然而，在实现治疗潜力的重要障碍是血脑屏障（BBB）的除其他组织的障碍，滴水不漏的大分子和蛋白质谱。然而，做这些障碍，允许细胞传代。所有一起，它预计，在周边的巨噬细胞疾病，绕过障碍，可以进行感染或发炎的部位制定的药物，标记和肽的自然过程。然而，这种技术只停留在发展。 10-12人类疾病的实验室和动物模型的支持，可用于诊断和治疗等应用和应用开发，细胞介导的交付，这是通过我们的作品。 2。纳米材料的准备工作药物输送和生物分布研究纳米材料的制备是在这个问题上的平行的手稿（参考并行手稿）的主题。结晶纳米粒子制造的所有程序都进行了层流罩。所有表面进行消毒，在使用前用70％酒精。这包括工作面上，手套外，任何泄漏。涵盖所有的复制70％的酒精溶液，立即用抹布。手套使用后丢弃，并没有进入任何其他实验室区域时穿。辅料，药品，无菌水/包含任何/所有试剂用于制造毒品载货颗粒只有带入工作区时，程序需要。仅用于无菌包裹移液器和成生物危险废物的容器，使用后丢弃。以下使用前用酒精消毒湿愿意仪器。工作区是立即清洗前，后用70％的酒精。纳米粒子的解决方案是在按照FDA的指导原则测试，以评估药物粒子的解决方案，用于对动物的细菌内毒素的情况下，热原。简单地说， <ol><li> 在体内使用的候选nanoformulations被复制取代具有相同大小的颗粒或精片的超顺磁性氧化铁（SPIO）涂装前适当的表面活性剂的药物核心或液滴。 </li><li>其次是大小，电荷，形状，和细胞毒性，以确定是否超顺磁性氧化铁模型系统nanoformulated作为候选药物相同的属性的措施。 </li><li>最后，细胞加载实验，以确定使用的标记细胞悬浮在琼脂凝胶组成的幽灵的细胞内的弛豫，与候选人的超顺磁性氧化铁模型nanoformultation孵化。 "幻影"一式三份，并准备在准备了一系列的浓度，以量化的弛豫由于超顺磁性氧化铁在细胞摄取。这提供了一个敏感指数，并确定是否nanoformulations可能影响氧化状态，并因此对超顺磁性氧化铁磁共振成像（MRI）扫描的知名度。 </li></ol> 3。方法和程序:动物的制备<ol><li>注射/导管。根据感兴趣的时间，注射可能需要使用导管内注入动物的MRI。使用非磁性的针和与最小直径的油管延伸，以尽量减少死腔注射线导管准备。导管应预填充注射或生理盐水，取决于死者的空间和总接受注射量的纳米材料的解决方案。如果可能的话，注射可能会遵循与生理盐水冲洗。如果急性倍的极端重要性，可进行预扫描，并注射液可在预定的时间完成磁铁外，前生物分布的措施跟进扫描。通常导管插入静脉注射尾静脉。 </li><li>麻醉和监测。扫描前，动物被放入一腔麻醉诱导。该商会是预充70％，n与1.5％异氟醚itrous氧化物和30％的氧气，以加速麻醉在动物发病，并最大限度地减少所需的时间，以确保动物不会醒来后，从会议厅中取出。一旦动物完全麻醉，动物是从会议厅中删除，并放入配备监测动物的呼吸频率和温度的同时，继续在设置供应异氟醚和扫描立体持有。 </li><li>动物持有人及调整事项:设置包括眼部润滑剂，以防止角膜溃疡。动物是轻轻用纱布包裹，纱布是到位的录音，在扫描过程中尽量减少热损失，并提供对正压呼吸监控。动物持有人都配备了可调齿棒，使头部的垂直和水平对齐。这是特别重要的高场MRI，头喙尾方向角与磁场的不均匀性，由于磁化率造成额外的困难。磁场的不均匀性是有害的高品质的 T 2 * 核磁共振的1 H核磁共振谱（1H MRS）和磁共振扩散张量成像（DTI） 。除了头喙尾方向角的正确定位，应避免头部转动的程度是可行的。允许在磁铁的动物持有人旋转，将提供轻微的旋转，这可能发生在动物的补偿。精心安置的头部和关注的角度插入的磁共振成像系统的动物之前，这可能会进一步减少。 </li><li>校准和匀场:一旦动物是在支架上正确放置在头部表面线圈，动物的初始位置是确定的喙尾方向的一维实时读数。信号仅限于该地区各地接待使用表面线圈，限制解释观察到的波的形式的需要。初始位置确定后，3架飞机的航向拍摄图像，以确定在扫描仪的动物的精确位置，并扫描（S）的利息所需的确切位置，以便运动。其次是调整磁场的同质性或"垫补"磁铁。这是通过映射场分布和计算精确的确定的空间上的电磁铁系列或"调整领域的同质化系统​​内的"匀场线圈测量的响应校正。匀场是使用多梯度回波序列和制图软件，由博士赫瑟林顿 13开发完成。同质化的地区是每一个人的成像方法研究该地区相匹配。一旦垫补是完整的，我们可以从动物获得的利益扫描（S）。 </li></ol> 4。数据采集<ol><li>高分辨率T 2 *加权成像。高分辨率三维T 2 *加权成像检测信号损失的地区，可以由超顺磁性氧化铁含有纳米粒子的生物分布。的大脑区域是确定的航向扫描和需要本地化扫描或额外的扫描规定。 2 * 150微米的各向同性分辨率加权MRI扫描，然后收购。一个高分辨率的三维梯度回顾收购回声MRI扫描鼠标头是使用采集参数的回波时间为5毫秒​​，重复时间= 50毫秒，30％的回声，翻转角= 35度，平均25毫米鸟笼量线圈= 2，视野= 20 × 20 × 20毫米，分辨率为128 × 128 × 128（体素大小= 150 × 150 × 150 微米 ），共采集时间= 30分钟。 </li><li>扩散张量成像（DTI）:扩散张量图像定量措施，组织细胞内水分子扩散的方向和幅度。因此，信号的相位是非常敏感的议案，扫描敏或"加权"微观水的运动。因此，单杆收购所需，以防止收购之间的相移，造成信号涂抹;和呼吸门控，以防止在信号采集总值的议案。因此，一个呼吸门控自旋回波弥散加权平面回波成像（EPI）的MR序列是聘用。再次，匀场的扫描区域是非常重要的，信号的演变过程的非共振效应导致的信号频率的位置不正，因此位置，在平面图像。 EPI采集参数包括14片，200 kHz带宽，在飞机收购零填充到256 × 256 96 × 96，和一个0.5毫米的切片厚度。所使用的扩散编码是一种平衡，旋转不变性和交替极性的二十面体计划（12方向tions）14,15。编码方案的目的是减少背景扩散梯度接头16。扩散加权B因子= 800毫米的小号-2，δ= 4毫秒，Δ= 15毫秒，Gdmax = 40 G /厘米，200μs的上升时间，7 B = 0的收购平均，平均每个B = 800编码方向，共采集时间为20-40分钟，这取决于呼吸速率。 </li><li>本地化的1 H核磁共振光谱（1H MRS）:1 H MRS可从在相同的成像会议期间获得的图像规定大脑区域。解剖位置上的图像，以订明获取光谱感兴趣的区域。一旦确定了该地区，是一个匹配的收购量的地区进行垫补，检查使用本地化的水频谱。然后，水抑制脉冲电源进行了优化，是测量水的频率，以确保水共振信号，并获得一个简短的测试频谱，以提供质量控制。如果光谱质量不足，系统设置，包括射频（RF）功率和垫片设置，检查。最后，如​​果质量仍然不足，第二个3飞机航向是运行，以确保动物已经从最初的扫描移动。根据我们的经验，这的光谱收购的重现性和准确性提供了一个非常高的程度。最后，光谱获取重置与系统之间的收购频率磁场漂移，以消除影响，并确保最终扫描的重现性和质量在短期块。在收购结束时，在预定的前置放大器增益的单脉冲频谱水是用来作为一个定量信号的幅度参考。 </li><li>组织学和Blockface影像后，最终在实验的时间序列MRI扫描会话，鼠标灌注，大脑和嵌入华侨城成块，复合使用一滴印度墨水已经变黑。该块被放入一个低温恒温器，切片和病理分析。 Blockface图像是使用数码相机（佳能EOS数码反叛300D佳能60毫米镜头USM微距镜头的超声波的EFS）安装在低温恒温器的前面，用一个自定义的装载和一个遥控开关触发的收购。整个脑容量的数字图像通过收购，每50微米。切片是组织学处理和染色后的登记编号，让内卷。个人blockface片对齐重建的三维体积，使用块概述了在低温恒温器头位置的抖动。大脑的体积，然后自动分段使用种子基于区域生长算法在分析软件包（AnalyzeDirect，Lexena，KS）。 </li></ol> 5。数据分析<ol><li>超顺磁性氧化铁检测使用MRI:超顺磁性氧化铁导致T 2 *加权成像信号损失，正因为如此，MRI信号无效是一个敏感的，但不具体组织的存在超顺磁性氧化铁标记。灵敏度是核磁共振成像扫描和超顺磁性氧化铁粒子的大小的空间分辨率，单一微米大小的粒子检测100微米的各向同性分辨率。在这些作品中，150微米与200纳米超顺磁性氧化铁颗粒各向同性分辨率。要提供超顺磁性氧化铁在大脑的灵敏度和特异性，小鼠扫描前注射超顺磁性氧化铁标记的细胞，以便在稍后的时间点减法图像在大脑中的细胞呈阳性的鉴定使用。 3D MRI扫描subimaged使用约束的水平集方法，在我们的实验室开发，正如先前所描述的17。 Subimaged大脑体积，然后配准，信号强度正常化，卷减去信号损失（超顺磁性氧化铁的存在），这是沿边缘不积极，以消除任何子像素登记错误的虚假信号检测与大脑的体积内的地区。 </li><li> Coregistration组织学和MRI检查:组织学和MRI之间Coregistration是通过使用一个共同的参考blockface形象。这种方法降低了纠正在制备过程中的不对称收缩和组织切片染色二维问题，因为我们在 18,19以前的作品中描述的主要问题的复杂性。在这里，超顺磁性氧化铁含有巨噬细胞在脑MRI和组织学检测表明良好的空间相关性，与预期高估MRI信号的损失和更大的敏感性少数细胞组织学12表明音量。这两个信号的精确定位提供了一个测量精度coregistration和组织学翘曲回片的原始形状。 </li><li>利息率（ROI）分析，英国贸工部的地区:英国贸工部扫描通常是选择一个解剖的投资回报率determ分析国家统计局在一个特定的解剖下部结构的平均扩散性质的组织。 扩散加权的数据分析使用在IDL（交互式数据语言，ITT视觉信息解决方案，博尔德，一氧化碳），如前面描述的15,20编写的自定义程序执行。分析产生张扩散的地图（λ1，λ2，λ3），平均扩散系数（D AV） 其中:D AV =（λ1 +λ2 +λ3）/ 3和各向异性分数（FA），其中: <img src="/files/ftp_upload/2459/2459eq1.jpg" alt="公式1" /> 横向（λ⊥=（λ2 +λ3）/ 2）和纵向（λLL =λ1）获得其他地方21所描述的扩散张量的组成部分。地图一旦兴建，投资回报率上绘制T 2加权MRI颜色编码λ1方向性地图覆盖。图1展示了艾滋病毒的小鼠模型中进行分析选择的地区的例子。 </li><li>光谱分析:促进脑的1 H MRS峰的代谢化合物的定量确定使用各种曲线拟合的方法之一。各种曲线拟合技术已经开发出来。在我们的实验室中，我们聘请jMRUI 23信号处理包，这是一个个别的代谢物谱的线性组合，最终频谱时域拟合的方法 （ QUEST）22。我们使用22个别代谢产物的潜在因素的基础。基础光谱模拟和检查使用的解决方案的个人代谢物的光谱。从一个单一的频谱曲线拟合结果的一个例子是如图2所示。 </li></ol> 6。代表性的成果英国贸工部和1HMRS的例子是在图1和2所示。 1H MRS 24-26和DTI 27个结果的其他例子可以看出，在我们以前的出版物。注射前T 2的例子*加权成像覆盖的黄色标记细胞的位置如图3所示。鼠标尾静脉注射标记的单核细胞衍生的巨噬细胞。五天以后，T2 *加权成像收购和处理描述的那样，以上。艾滋病毒感染人类巨噬细胞注射入脑，这是检测小鼠单核细胞衍生的巨噬细胞，鼠标准备。进一步双方检测标记的细胞和组织学coregistration的例子可以看出，在我们的10,12以前的出版物。 <img src="/files/ftp_upload/2459/2459fig1.jpg" alt="图1" /> 图1。贸工部指标分析地区的写照。 <img src="/files/ftp_upload/2459/2459fig2.jpg" alt="图2" /> 图2。光谱装修使用jMRUI信号处理套件的追求。 <img src="/files/ftp_upload/2459/2459fig3.jpg" alt="图3" /> 图3。超顺磁性氧化铁标记从一个大脑区域与协调性脑炎的外周血细胞迁移检测。细胞的位置（黄色）代表片覆盖从T 2 *加权MRI在详细的文字收购。

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M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophage+delivery+of+nanoformulated+antiretroviral+drug+to+the+brain+in+a+murine+model+of+neuroAIDS.">Macrophage delivery of nanoformulated antiretroviral drug to the brain in a murine model of neuroAIDS.</a> J Immunol. 183, 661-669 (2009).</li><li>Liu, Y., Uberti, M. G., Dou, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ingress+of+blood-borne+macrophages+across+the+blood-brain+barrier+in+murine+HIV-1+encephalitis.">Ingress of blood-borne macrophages across the blood-brain barrier in murine HIV-1 encephalitis.</a> J Neuroimmunol. 200, 41-52 (2008).</li><li>Hetherington, H. P., Chu, W. J., Gonen, O., Pan, 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=Robust+fully+automated+shimming+of+the+human+brain+for+high-field+1H+spectroscopic+imaging.">Robust fully automated shimming of the human brain for high-field 1H spectroscopic imaging.</a> Magn Reson Med. 56, 26-33 (2006).</li><li>Hasan, K. M., Parker, D. L., Alexander, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+gradient+encoding+schemes+for+diffusion-tensor+MRI.">Comparison of gradient encoding schemes for diffusion-tensor MRI.</a> J Magn Reson Imaging. 13, 769-780 (2001).</li><li>Hasan, K. M., Basser, P. J., Parker, D. L., Alexander, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analytical+computation+of+the+eigenvalues+and+eigenvectors+in+DT-MRI.">Analytical computation of the eigenvalues and eigenvectors in DT-MRI.</a> J Magn Reson. 152, 41-47 (2001).</li><li>Neeman, M., Freyer, J. P., Sillerud, L. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+simple+method+for+obtaining+cross-term-free+images+for+diffusion+anisotropy+studies+in+NMR+microimaging.">A simple method for obtaining cross-term-free images for diffusion anisotropy studies in NMR microimaging.</a> Magn Reson Med. 21, 138-143 (1991).</li><li>Uberti, M. G., Boska, M. D., Liu, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+semi-automatic+image+segmentation+method+for+extraction+of+brain+volume+from+in+vivo+mouse+head+magnetic+resonance+imaging+using+Constraint+Level+Sets.">A semi-automatic image segmentation method for extraction of brain volume from in vivo mouse head magnetic resonance imaging using Constraint Level Sets.</a> J of Neurosci Methods. 179, 338-344 (2009).</li><li>Liu, Y., Uberti, M. G., Dou, H., Mosley, R. L., Gendelman, H. E., Boska, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+Image+Warping+Technique+for+Rodent+Brain+MRI-Histology+Registration+Based+On+Thin-Plate+Splines+with+Landmark+Optimization.">An Image Warping Technique for Rodent Brain MRI-Histology Registration Based On Thin-Plate Splines with Landmark Optimization.</a> Proc Soc Photo Opt Instrum Eng. 7259, 72592-K-72597-K (2009).</li><li>Uberti, M. G., Liu, Y., Dou, H., Mosley, R. L., Gendelman, H. E., Boska, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Registration+of+in+vivo+MR+to+histology+of+rodent+brains+using+blockface+imaging.">Registration of in vivo MR to histology of rodent brains using blockface imaging.</a> Proc Soc Photo Opt Instrum Eng. 7262, 726213-726213 (2009).</li><li>Basser, P. J., Mattiello, J., LeBihan, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estimation+of+the+effective+self-diffusion+tensor+from+the+NMR+spin+echo.">Estimation of the effective self-diffusion tensor from the NMR spin echo.</a> J Magn Reson B. 103, 247-254 (1994).</li><li>Hasan, K. M., Narayana, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Retrospective+measurement+of+the+diffusion+tensor+eigenvalues+from+diffusion+anisotropy+and+mean+diffusivity+in+DTI.">Retrospective measurement of the diffusion tensor eigenvalues from diffusion anisotropy and mean diffusivity in DTI.</a> Magn Reson Med. 56, 130-137 (2006).</li><li>Ratiney, H., Sdika, M., Coenradie, Y., Cavassila, S., Ormondt, D. v. a. n., Graveron-Demilly, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Time-domain+semi-parametric+estimation+based+on+a+metabolite+basis+set.">Time-domain semi-parametric estimation based on a metabolite basis set.</a> NMR Biomed. 18, 1-13 (2005).</li><li>Naressi, A., Couturier, C., Castang, I., Beer, R. d. e., Graveron-Demilly, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Java-based+graphical+user+interface+for+MRUI,+a+software+package+for+quantitation+of+in+vivo/medical+magnetic+resonance+spectroscopy+signals.">Java-based graphical user interface for MRUI, a software package for quantitation of in vivo/medical magnetic resonance spectroscopy signals.</a> Comput Biol Med. 31, 269-286 (2001).</li><li>Boska, L. e. w. i. s., Destache, T. B., J, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+1H+magnetic+resonance+spectroscopic+imaging+determines+therapeutic+immunization+efficacy+in+an+animal+model+of+Parkinson's+disease.">Quantitative 1H magnetic resonance spectroscopic imaging determines therapeutic immunization efficacy in an animal model of Parkinson's disease.</a> J Neurosci. 25, 1691-1700 (2005).</li><li>Mosley, R. L., Benner, E. J., Kadiu, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neuroinflammation,+Oxidative+Stress+and+the+Pathogenesis+of+Parkinson's+Disease.">Neuroinflammation, Oxidative Stress and the Pathogenesis of Parkinson's Disease.</a> Clin Neurosci Res. 6, 261-281 (2006).</li><li>Nelson, J. A., Dou, H., Ellison, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coregistration+of+quantitative+proton+magnetic+resonance+spectroscopic+imaging+with+neuropathological+and+neurophysiological+analyses+defines+the+extent+of+neuronal+impairments+in+murine+human+immunodeficiency+virus+type-1+encephalitis.">Coregistration of quantitative proton magnetic resonance spectroscopic imaging with neuropathological and neurophysiological analyses defines the extent of neuronal impairments in murine human immunodeficiency virus type-1 encephalitis.</a> J Neurosci Res. 80, 562-575 (2005).</li><li>Boska, H. a. s. a. n., Kibuule, K. M., D, . <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+diffusion+tensor+imaging+detects+dopaminergic+neuronal+degeneration+in+a+murine+model+of+Parkinson's+disease.">Quantitative diffusion tensor imaging detects dopaminergic neuronal degeneration in a murine model of Parkinson's disease.</a> Neurobiol Dis. 26, 590-596 (2007).</li><li>Liu, W., Frank, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+and+quantification+of+magnetically+labeled+cells+by+cellular+MRI.">Detection and quantification of magnetically labeled cells by cellular MRI.</a> Eur J Radiol. 70, 258-264 (2009).</li><li>Balchandani, P., Yamada, M., Pauly, J., Yang, P., Spielman, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Self-refocused+spatial-spectral+pulse+for+positive+contrast+imaging+of+cells+labeled+with+SPIO+nanoparticles.">Self-refocused spatial-spectral pulse for positive contrast imaging of cells labeled with SPIO nanoparticles.</a> Magn Reson Med. 62, 183-192 (2009).</li><li>Stuber, M., Gilson, W. D., Schar, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Positive+contrast+visualization+of+iron+oxide-labeled+stem+cells+using+inversion-recovery+with+ON-resonant+water+suppression+(IRON).">Positive contrast visualization of iron oxide-labeled stem cells using inversion-recovery with ON-resonant water suppression (IRON).</a> Magn Reson Med. 58, 1072-1077 (2007).</li><li>Suzuki, Y., Cunningham, C. H., Noguchi, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+serial+evaluation+of+superparamagnetic+iron-oxide+labeled+stem+cells+by+off-resonance+positive+contrast.">In vivo serial evaluation of superparamagnetic iron-oxide labeled stem cells by off-resonance positive contrast.</a> Magn Reson Med. 60, 1269-1275 (2008).</li><li>Kim, Y. B., Bae, K. H., Yoo, S. S., Park, T. G., H, P. a. r. k. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Positive+contrast+visualization+for+cellular+magnetic+resonance+imaging+using+susceptibility-weighted+echo-time+encoding.">Positive contrast visualization for cellular magnetic resonance imaging using susceptibility-weighted echo-time encoding.</a> Magn Reson Imaging. 27, 601-610 (2009).</li><li>Zhou, R., Idiyatullin, D., Moeller, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SWIFT+detection+of+SPIO-labeled+stem+cells+grafted+in+the+myocardium.">SWIFT detection of SPIO-labeled stem cells grafted in the myocardium.</a> Magn Reson Med. 63, 1154-1161 .</li></ol>

组织学与体内成像效果的准确登记，是在成像生物标志物进行检测和神经元疾病的分期发展的关键一步。一些成像指标可能与总值的形态学变化，包括用于检测脑白质病和癌症的存在组织的磁弛豫特性的变化密切相关。其他更细微的方法，如英国贸工部，有可能发现早期细胞的变化可能不被探测到由疾病引起的病理变化不出现，直到后来的疾病阶段。还有其他的标志物，如光谱标记，可能是早期和可逆的变化，即使是微妙的细胞改变之前的指标。 体内的分布，可确定的非侵入性使用的各种方法。主要的非侵入性的方法是正电子发射断层扫描（PET），单光子发射计算机断层显像（SPECT），光学成像和MRI。许多生物分布，核医学成像（PET和SPECT）多年来一直使用，但这些方法都是有限的标签，尤其是用于PET示踪剂化合物或纳米材料，使用的放射性示踪剂的半衰期。光学成像，可用于小型啮齿类动物，但不能转化人类使用容易，如表面的肿瘤，由于光吸收和光散射的地区除外。此外，它是难以量化的光信号，这些同样的原因。 MRI检查使用持久性，如超顺磁性氧化铁的一个星期内，可在体内追踪标签。 ，这也必须谨慎使用，标签可以转移到不同的细胞或身体再吸收。 可以提供多种方法检测超顺磁性氧化铁在MRI的特异性。检测方法，提供正面以及负面的信号，用于提高检测组织中存在的超顺磁性氧化铁的特异性的MRI。在这项工作中使用的加减法已被他人使用， 以及 28 。其他办法包括关闭的共振检测 29-31，相位敏感的成像产生超顺磁性氧化铁空隙32，零回波时间图像，使用的T1加权产生一个积极的信号强度，超顺磁性氧化铁33地区附近的一个特定模式。提高标签定量方法的进步，敏感性和特异性，今天是一个活跃的研究领域。

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		<th>Catalogue Number</th>
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<tr>
<td>Isoflurane</td>
<td>&nbsp;</td>
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<td>Medical Oxygen</td>
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<td>Isoflurane vaporizer</td>
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<td>Rodent gas anesthesia mask</td>
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<td>MRI compatible Stereotactic head holder</td>
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<td>Syringe</td>
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<td>Polyethylene catheter tubing</td>
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<td>Non-magnetic needle</td>
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<td>Eye lubricant</td>
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<td>Gauze</td>
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<td>Tape</td>
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<td>Perfusion media</td>
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<td>OCT compound for embedding tissue</td>
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<td>MRI system</td>
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<td>Digital Camera</td>
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<td>Tissue Sectioning Cryostat</td>
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registered bioimaging of nanomaterials for diagnostic and therapeutic monitoring

Nanomedications可以通过血液传染的单核细胞 - 巨噬细胞，成网状内皮系统（RES，脾，肝，淋巴结）进行和结束机关。后者包括肺，RES和大脑，在人类免疫缺陷病毒（HIV - 1）感染的手术。值得注意的是在积极的HIV - 1复制和炎症部位的领域进入到组织中巨噬细胞。为了评估nanocarriers，超顺磁性铁氧化物和/或涂层与表面活性剂的药物载货颗粒的巨噬细胞的潜力，肠外注入HIV - 1病毒脑炎小鼠。这样做是粒子和药物体内分布的定量评估。磁共振成像（MRI）的测试结果进行了验证，通过组织学coregistration和增强的图像处理。器官的疾病，如脑组织学改变为代表的MRI评估。 nanoformulations强劲迁移到局灶性脑炎等领域的示范规定"利用先进的生物成像技术监测巨噬细胞迁移的"概念证明"。更重要的是，在脑组织病理学异常相关疾病可行的细胞分布的研究一般实用的MRI与生物成像参数。我们断定，使用这种方法，可以提供实时翻译潜在人类疾病负担和疗效指数。

Watch this Scientific Journal Video about Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring at JoVE.com

Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring

用于评估细胞生物分布的纳米粒子的生物成像方法适用于nanoformulated化合物的治疗和诊断监测。病理coregistration评估时，此处所描述的方法的敏感性和特异性。该方法提供了一个从啮齿类动物对人类应用的翻译途径。

注册生物成像，纳米材料可用于诊断和治疗监测

Nanomedications can be carried by blood borne monocyte-macrophages into the reticuloendothelial system (RES; spleen, liver, lymph nodes) and to end ...

registered-bioimaging-nanomaterials-for-diagnostic-therapeutic

Research

JoVE Journal

Bioengineering

10.3K 次观看.  University of Nebraska Medical Center. 用于评估细胞生物分布的纳米粒子的生物成像方法适用于nanoformulated化合物的治疗和诊断监测。病理coregistration评估时，此处所描述的方法的敏感性和特异性。该方法提供了一个从啮齿类动物对人类应用的翻译途径。

视频: Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring

Low Molecular Weight Protein Enrichment on Mesoporous Silica Thin Films for Biomarker Discovery

The identification of circulating biomarkers holds great potential for non invasive approaches in early diagnosis and prognosis, as well as for the monitoring of therapeutic efficiency.1-3 The circulating low molecular weight proteome (LMWP) composed of small proteins shed from tissues and cells or peptide fragments derived from the proteolytic degradation of larger proteins, has been associated with the pathological condition in patients and likely reflects the state of disease.4,5 Despite these potential clinical applications, the use of Mass Spectrometry (MS) to profile the LMWP from biological fluids has proven to be very challenging due to the large dynamic range of protein and peptide concentrations in serum.6 Without sample pre-treatment, some of the more highly abundant proteins obscure the detection of low-abundance species in serum/plasma. Current proteomic-based approaches, such as two-dimensional polyacrylamide gel-electrophoresis (2D-PAGE) and shotgun proteomics methods are labor-intensive, low throughput and offer limited suitability for clinical applications.7-9 Therefore, a more effective strategy is needed to isolate LMWP from blood and allow the high throughput screening of clinical samples. 
Here, we present a fast, efficient and reliable multi-fractionation system based on mesoporous silica chips to specifically target and enrich LMWP.10,11 Mesoporous silica (MPS) thin films with tunable features at the nanoscale were fabricated using the triblock copolymer template pathway. Using different polymer templates and polymer concentrations in the precursor solution, various pore size distributions, pore structures, connectivity and surface properties were determined and applied for selective recovery of low mass proteins. The selective parsing of the enriched peptides into different subclasses according to their physicochemical properties will enhance the efficiency of recovery and detection of low abundance species. In combination with mass spectrometry and statistic analysis, we demonstrated the correlation between the nanophase characteristics of the mesoporous silica thin films and the specificity and efficacy of low mass proteome harvesting. The results presented herein reveal the potential of the nanotechnology-based technology to provide a powerful alternative to conventional methods for LMWP harvesting from complex biological fluids. Because of the ability to tune the material properties, the capability for low-cost production, the simplicity and rapidity of sample collection, and the greatly reduced sample requirements for analysis, this novel nanotechnology will substantially impact the field of proteomic biomarker research and clinical proteomic assessment.

We developed a technology based on mesoporous silica thin film for the selective recovery of low molecular weight proteins and peptides from human serum. The physico-chemical properties of our mesoporous chips were finely tuned to provide substantial control in peptide enrichment and consequently profile the serum proteome for diagnostic purposes.

生物标志物发现的介孔二氧化硅薄膜的低分子量蛋白质富集

The identification of circulating biomarkers holds great potential for non invasive approaches in early diagnosis and prognosis, as well as for the ...

科研

生物工程

Hollow Microneedle-based Sensor for Multiplexed Transdermal Electrochemical Sensing

The development of a minimally invasive multiplexed monitoring system for rapid analysis of biologically-relevant molecules could offer individuals suffering from chronic medical conditions facile assessment of their immediate physiological state. Furthermore, it could serve as a research tool for analysis of complex, multifactorial medical conditions. In order for such a multianalyte sensor to be realized, it must be minimally invasive, sampling of interstitial fluid must occur without pain or harm to the user, and analysis must be rapid as well as selective.
Initially developed for pain-free drug delivery, microneedles have been used to deliver vaccines and pharmacologic agents (e.g., insulin) through the skin.1-2 Since these devices access the interstitial space, microneedles that are integrated with microelectrodes can be used as transdermal electrochemical sensors. Selective detection of glucose, glutamate, lactate, hydrogen peroxide, and ascorbic acid has been demonstrated using integrated microneedle-electrode devices with carbon fibers, modified carbon pastes, and platinum-coated polymer microneedles serving as transducing elements.3-7,8
This microneedle sensor technology has enabled a novel and sophisticated analytical approach for in situ and simultaneous detection of multiple analytes. Multiplexing offers the possibility of monitoring complex microenvironments, which are otherwise difficult to characterize in a rapid and minimally invasive manner. For example, this technology could be utilized for simultaneous monitoring of extracellular levels of, glucose, lactate and pH,9 which are important metabolic indicators of disease states7,10-14 (e.g., cancer proliferation) and exercise-induced acidosis.15

This article details the construction of a multiplexed microneedle-based sensor. The device is being developed for in situ sampling and electrochemical analysis of multiple analytes in a rapid and selective manner. We envision clinical medicine and biomedical research uses for these microneedle-based sensors.

复透皮电化学传感的空心微针为基础的传感器

The development of a minimally invasive multiplexed monitoring system for rapid analysis of biologically-relevant molecules could offer individuals ...

Mass Cytometry: Protocol for Daily Tuning and Running Cell Samples on a CyTOF Mass Cytometer

In recent years, the rapid analysis of single cells has commonly been performed using flow cytometry and fluorescently-labeled antibodies. However, the issue of spectral overlap of fluorophore emissions has limited the number of simultaneous probes. In contrast, the new CyTOF mass cytometer by DVS Sciences couples a liquid single-cell introduction system to an ICP-MS.1 Rather than fluorophores, chelating polymers containing highly-enriched metal isotopes are coupled to antibodies or other specific probes.2-5 Because of the metal purity and mass resolution of the mass cytometer, there is no "spectral overlap" from neighboring isotopes, and therefore no need for compensation matrices. Additionally, due to the use of lanthanide metals, there is no biological background and therefore no equivalent of autofluorescence. With a mass window spanning atomic mass 103-203, theoretically up to 100 labels could be distinguished simultaneously. Currently, more than 35 channels are available using the chelating reagents available from DVS Sciences, allowing unprecedented dissection of the immunological profile of samples.6-7
Disadvantages to mass cytometry include the strict requirement for a separate metal isotope per probe (no equivalent of forward or side scatter), and the fact that it is a destructive technique (no possibility of sorting recovery). The current configuration of the mass cytometer also has a cell transmission rate of only ~25%, thus requiring a higher input number of cells.
Optimal daily performance of the mass cytometer requires several steps. The basic goal of the optimization is to maximize the measured signal intensity of the desired metal isotopes (M) while minimizing the formation of oxides (M+16) that will decrease the M signal intensity and interfere with any desired signal at M+16. The first step is to warm up the machine so a hot, stable ICP plasma has been established. Second, the settings for current and make-up gas flow rate must be optimized on a daily basis. During sample collection, the maximum cell event rate is limited by detector efficiency and processing speed to 1000 cells/sec. However, depending on the sample quality, a slower cell event rate (300-500 cells/sec) is usually desirable to allow better resolution between cells events and thus maximize intact singlets over doublets and debris. Finally, adequate cleaning of the machine at the end of the day helps minimize background signal due to free metal.

The steps necessary for daily tuning and optimization of the performance of a CyTOF mass cytometer are described. Comments on optimal sample preparation and flow rate are discussed

质量流式细胞术:协议，每日调整和执行细胞的样品上一个CyTOF的质量流式细胞仪

In recent years, the rapid analysis of single cells has commonly been performed using flow cytometry and fluorescently-labeled antibodies. However, the ...

Determination of the Transport Rate of Xenobiotics and Nanomaterials Across the Placenta using the ex vivo Human Placental Perfusion Model

Decades ago the human placenta was thought to be an impenetrable barrier between mother and unborn child. However, the discovery of thalidomide-induced birth defects and many later studies afterwards proved the opposite. Today several harmful xenobiotics like nicotine, heroin, methadone or drugs as well as environmental pollutants were described to overcome this barrier. With the growing use of nanotechnology, the placenta is likely to come into contact with novel nanoparticles either accidentally through exposure or intentionally in the case of potential nanomedical applications. Data from animal experiments cannot be extrapolated to humans because the placenta is the most species-specific mammalian organ 1. Therefore, the ex vivo dual recirculating human placental perfusion, developed by Panigel et al. in 1967 2 and continuously modified by Schneider et al. in 1972 3, can serve as an excellent model to study the transfer of xenobiotics or particles.
Here, we focus on the ex vivo dual recirculating human placental perfusion protocol and its further development to acquire reproducible results.
The placentae were obtained after informed consent of the mothers from uncomplicated term pregnancies undergoing caesarean delivery. The fetal and maternal vessels of an intact cotyledon were cannulated and perfused at least for five hours. As a model particle fluorescently labelled polystyrene particles with sizes of 80 and 500 nm in diameter were added to the maternal circuit. The 80 nm particles were able to cross the placental barrier and provide a perfect example for a substance which is transferred across the placenta to the fetus while the 500 nm particles were retained in the placental tissue or maternal circuit. The ex vivo human placental perfusion model is one of few models providing reliable information about the transport behavior of xenobiotics at an important tissue barrier which delivers predictive and clinical relevant data.

Determination of the Transport Rate of Xenobiotics and Nanomaterials Across the Placenta using the ex vivo Human Placental Perfusion Model

The ex vivo dual recirculating human placental perfusion model can be used to investigate the transfer of xenobiotics and nanoparticles across the human placenta. In this video protocol we describe the equipment and techniques required for a successful execution of a placenta perfusion.

通过胎盘的外来物质和纳米材料的运输率测定<em&gt;体外</em&gt;人胎盘灌注型号

Decades ago the human placenta was thought to be an impenetrable barrier between mother and unborn child. However, the discovery of thalidomide-induced ...

Rapid and Low-cost Prototyping of Medical Devices Using 3D Printed Molds for Liquid Injection Molding

Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications.

We have devised a method for low-cost and rapid prototyping of liquid elastomer rubber injection molded devices by using fused deposition modeling 3D printers for mold design and a modified desiccator as a liquid injection system.

医疗器械的使用3D印刷模具的液体注射成型快速，低成本原型

Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using ...

Multicolor Fluorescence Detection for Droplet Microfluidics Using Optical Fibers

Fluorescence assays are the most common readouts used in droplet microfluidics due to their bright signals and fast time response. Applications such as multiplex assays, enzyme evolution, and molecular biology enhanced cell sorting require the detection of two or more colors of fluorescence. Standard multicolor detection systems that couple free space lasers to epifluorescence microscopes are bulky, expensive, and difficult to maintain. In this paper, we describe a scheme to perform multicolor detection by exciting discrete regions of a microfluidic channel with lasers coupled to optical fibers. Emitted light is collected by an optical fiber coupled to a single photodetector. Because the excitation occurs at different spatial locations, the identity of emitted light can be encoded as a temporal shift, eliminating the need for more complicated light filtering schemes. The system has been used to detect droplet populations containing four unique combinations of dyes and to detect sub-nanomolar concentrations of fluorescein.

Multicolor fluorescence detection in droplet microfluidics typically involves bulky and complex epifluorescence microscope-based detection systems. Here we describe a compact and modular multicolor detection scheme that utilizes an array of optical fibers to temporally encode multicolor data collected by a single photodetector.

使用多色荧光检测液滴微流控光纤

Fluorescence assays are the most common readouts used in droplet microfluidics due to their bright signals and fast time response. Applications such as ...

The Synthesis of RGD-functionalized Hydrogels as a Tool for Therapeutic Applications

The use of polymers as biomaterials has provided significant advantages in therapeutic applications. In particular, the possibility to modify and functionalize polymer chains with compounds that are able to improve biocompatibility, mechanical properties, or cell viability allows the design of novel materials to meet new challenges in the biomedical field. With the polymer functionalization strategies, click chemistry is a powerful tool to improve cell-compatibility and drug delivery properties of polymeric devices. Similarly, the fundamental need of biomedicine to use sterile tools to avoid potential adverse-side effects, such as toxicity or contamination of the biological environment, gives rise to increasing interest in the microwave-assisted strategy.
The combination of click chemistry and the microwave-assisted method is suitable to produce biocompatible hydrogels with desired functionalities and improved performances in biomedical applications. This work aims to synthesize RGD-functionalized hydrogels. RGD (arginylglycylaspartic acid) is a tripeptide that can mimic cell adhesion proteins and bind to cell-surface receptors, creating a hospitable microenvironment for cells within the 3D polymeric network of the hydrogels. RGD functionalization occurs through Huisgen 1,3-dipolar cycloaddition. Some PAA carboxyl groups are modified with an alkyne moiety, whereas RGD is functionalized with azido acid as the terminal residue of the peptide sequence. Finally, both products are used in a copper catalyzed click reaction to permanently link the peptide to PAA. This modified polymer is used with carbomer, agarose and polyethylene glycol (PEG) to synthesize a hydrogel matrix. The 3D structure is formed due to an esterification reaction involving carboxyl groups from PAA and carbomer and hydroxyl groups from agarose and PEG through microwave-assisted polycondensation. The efficiency of the gelation mechanism ensures a high degree of RGD functionalization. In addition, the procedure to load therapeutic compounds or biological tools within this functionalized network is very simple and reproducible.

We present a protocol for the synthesis of RGD-functionalized hydrogels as devices for cell and drug delivery. The procedure involves copper catalyzed alkyne-azide cycloaddition (CuAAC) between alkyne-modified polyacrylic acid (PAA) and a RGD-azide derivative. The hydrogels are formed using microwave-assisted polycondensation and their physicochemical properties are investigated.

RGD功能化水凝胶作为治疗应用的工具合成

The use of polymers as biomaterials has provided significant advantages in therapeutic applications. In particular, the possibility to modify and ...

Synthesis of Cationized Magnetoferritin for Ultra-fast Magnetization of Cells

Many important biomedical applications, such as cell imaging and remote manipulation, can be achieved by labeling cells with superparamagnetic iron oxide nanoparticles (SPIONs). Achieving sufficient cellular uptake of SPIONs is a challenge that has traditionally been met by exposing cells to elevated concentrations of SPIONs or by prolonging exposure times (up to 72 hr). However, these strategies are likely to mediate toxicity. Here, we present the synthesis of the protein-based SPION magnetoferritin as well as a facile surface functionalization protocol that enables rapid cell magnetization using low exposure concentrations. The SPION core of magnetoferritin consists of cobalt-doped iron oxide with an average particle diameter of 8.2 nm mineralized inside the cavity of horse spleen apo-ferritin. Chemical cationization of magnetoferritin produced a novel, highly membrane-active SPION that magnetized human mesenchymal stem cells (hMSCs) using incubation times as short as one minute and iron concentrations as lows as 0.2 mM.

A protocol for the synthesis and cationization of cobalt-doped magnetoferritin is presented, as well as a method to rapidly magnetize stem cells with cationized magnetoferritin.

对细胞的超快磁化阳离子化Magnetoferritin的合成

Many important biomedical applications, such as cell imaging and remote manipulation, can be achieved by labeling cells with superparamagnetic iron oxide ...

Synthesis of Infectious Bacteriophages in an E. coli-based Cell-free Expression System

A new generation of cell-free transcription-translation (TXTL) systems, engineered to have a greater versatility and modularity, provide novel capabilities to perform basic and applied sciences in test tube reactions. Over the past decade, cell-free TXTL has become a powerful technique for a broad range of novel multidisciplinary research areas related to quantitative and synthetic biology. The new TXTL platforms are particularly useful to construct and interrogate biochemical systems through the execution of synthetic or natural gene circuits. In vitro TXTL has proven convenient to rapidly prototype regulatory elements and biological networks as well as to recapitulate molecular self-assembly mechanisms found in living systems. In this article, we describe how infectious bacteriophages, such as MS2 (RNA), &#934;&#935;174 (ssDNA), and T7 (dsDNA), are entirely synthesized from their genome in one-pot reactions using an all Escherichia coli, cell-free TXTL system. Synthesis of the three coliphages is quantified using the plaque assay. We show how the yield of synthesized phage depends on the biochemical settings of the reactions. Molecular crowding, emulated through a controlled concentration of PEG 8000, affects the amount of synthesized phages by orders of magnitudes. We also describe how to amplify the phages and how to purify their genomes. The set of protocols and results presented in this work should be of interest to multidisciplinary researchers involved in cell-free synthetic biology and bioengineering.

Synthesis of Infectious Bacteriophages in an E. coli-based Cell-free Expression System

A new generation of cell-free transcription-translation platforms has been engineered to construct biochemical systems in vitro through the execution of gene circuits. In this article, we describe how bacteriophages, such as MS2, &#934;&#935;174, and T7, are synthesized from their genome using an all E. coli cell-free TXTL system.

传染性噬菌体大肠杆菌-合成基于无细胞表达系统

A new generation of cell-free transcription-translation (TXTL) systems, engineered to have a greater versatility and modularity, provide novel ...

An Ultrahigh-throughput Microfluidic Platform for Single-cell Genome Sequencing

Sequencing technologies have undergone a paradigm shift from bulk to single-cell resolution in response to an evolving understanding of the role of cellular heterogeneity in biological systems. However, single-cell sequencing of large populations has been hampered by limitations in processing genomes for sequencing. In this paper, we describe a method for single-cell genome sequencing (SiC-seq) which uses droplet microfluidics to isolate, amplify, and barcode the genomes of single cells. Cell encapsulation in microgels allows the compartmentalized purification and tagmentation of DNA, while a microfluidic merger efficiently pairs each genome with a unique single-cell oligonucleotide barcode, allowing &gt;50,000 single cells to be sequenced per run. The sequencing data is demultiplexed by barcode, generating groups of reads originating from single cells. As a high-throughput and low-bias method of single-cell sequencing, SiC-seq will enable a broader range of genomic studies targeted at diverse cell populations.

Single-cell sequencing reveals genotypic heterogeneity in biological systems, but current technologies lack the throughput necessary for the deep profiling of community composition and function. Here, we describe a microfluidic workflow for sequencing &gt;50,000 single-cell genomes from diverse cell populations.

单细胞基因组测序的超高通量微流控平台

Sequencing technologies have undergone a paradigm shift from bulk to single-cell resolution in response to an evolving understanding of the role of ...