激光捕获显微切割技术在植物基因组研究中的应用

植物的生长和发育在很大程度上取决于组织和(或)器官特异表达的基因, 但要获取某一发育阶段的特异细胞类群来进行基因表达分析又是相当困难的。近年发展起来的激光捕获显微切割技术可以在显微镜下快速准确地获取单一的细胞类群, 甚至单个细胞, 成功地解决了组织中细胞的异质性问题。介绍了该技术的原理, 并对其在植物中的应用进展情况做了综述, 同时指出了该技术在植物中应用的可能发展方向。     

激光捕获显微切割技术新进展

最近发展起来的激光捕获显微切割技术,成功地解决了从所需标本不同成分中获取纯净细胞这一问题,具有简单、快速、不需熟练技巧以及精确度高等多功能特点,目前,广泛用于肿瘤学、细胞发生学和其他学科的研究。可以预测,激光捕获显微切割技术,作为一个链接研究形态学与分子事件联系的上下游技术平台,必将在人类后基因组时代发挥重要作用。     

激光捕获显微切割技术在膀胱移行细胞癌相关基因研究中的应用

背景与目的:激光捕获显微切割技术 (LCM)是获取均一目的细胞的有效方法。利用LCM技术从膀胱粘膜中分离膀胱移行上皮细胞从肿瘤间质细胞中分离膀胱癌细胞,进行RNA提取、纯化、浓缩以备进一步研究。方法:采用LCM技术分别从正常膀胱粘膜及膀胱癌组织冰冻切片中获取膀胱移行上皮细胞及膀胱癌细胞,提取RNA,并对微量RNA进行纯化、浓缩。然后用RT PCR验证TotalRNA中β actin基因表达水平。结果:对照实验Ⅰ证实经LCM后RNA完整性较好;经对照实验Ⅱ初步确定设定条件下LCMshooting次数与可获得RNA量间对应关系。从膀胱粘膜中捕获膀胱移行上皮细胞 2 5万shootings;从膀胱癌组织中获取癌细胞 2 0万shootings。经RT PCR验证β actin基因表达表达完整。结论:使用LCM技术能成功地获取较为均一的研究目的细胞,RNA完整性较好,能用于进一步研究中。     

激光显微切割植物细胞的研究新趋势

2006年以来,激光显微切割技术(LM)逐渐发展成为植物及植物-微生物互作领域的常用技术.从激光技术方面,激光捕获显微切割(LCM)和激光显微切割及压力弹射(LMPC)成为两大主流技术.在材料准备方面,改良的石蜡包埋切片技术在植物成熟组织切割中应用日益广泛,而冰冻包埋切片则在幼嫩组织切割中十分有效。激光显微切割所得样品主要仍用于RNA水平的基因表达分析,而且能从全基因组规模上深度分析基因表达谱.此外,对激光显微切割所得细胞进行小分子代谢物的分析也取得了实质性成果。总之,激光显微切割技术作为从复杂背景中直接分离特定细胞(群)的一种有效工具,在植物分子生物学研究中的应用已经成熟,正为提高植物研究的精准度做出贡献.     

激光捕获显微切割技术在肿瘤研究中的进展

激光捕获显微切割技术(LCM,Laser Capture Microdissection)是目前最先进的组织纯化技术,LCM结合各种基于细胞、DNA、RNA、及蛋白质的分子生物学技术成功运用于肿瘤学研究的各个方面,通过对切割后细胞的基因组,转录组,蛋白组等分析研究后得到了大量有用的结论.本文就其在肿瘤学研究中的应用进行综述.     

激光捕获显微切割在肿瘤多组学研究中的应用进展

当今社会,肿瘤因其高发病率和高死亡率成为威胁人类健康的重要疾病,研究者们对其发病机制及治疗手段的研究和探索也在不断深入。随着单细胞多组学测序技术的发展,肿瘤组织的异质性问题逐渐被研究人员所认识。为了解决这一问题,激光捕获显微切割（laser capture microdissection,LCM）技术应运而生。LCM技术是一种在显微镜直视下从器官或组织中准确获取某种特定的细胞群或单个细胞的样本收集技术。LCM技术结合多种分子生物学手段可以对异质性组织进行多组学研究,丰富了现有的肿瘤蛋白质组学、基因组学以及转录组学图谱,因此,LCM技术成为研究特异性表达及分子机制的有力工具,在肿瘤学领域得到广泛应用。基于此,对LCM的原理、优势及其在肿瘤多组学研究中的应用进行了综述,并对其未来可能的发展方向进行了展望,以期为肿瘤的研究和治疗提供新的思路。     

激光显微切割技术及其在植物学研究中的应用

激光显微切割技术是目前最为成功的解决组织中细胞异质性问题的技术。介绍了激光显微切割技术的产生和影响因素,并对其在植物基因表达分析、植物生殖和胚胎发育研究、代谢物分析以及植物与微生物互作等方面的研究做简单综述。     

激光捕获显微切割技术结合^18O标记定量蛋白质组技术在胃癌标志物筛查中的应用研究

建立一种更加精确地分离鉴定胃癌特异肿瘤标志物的定量蛋白质组学技术.首先采用激光捕获显微切割技术(LCM)纯化胃腺癌细胞及胃黏膜良性上皮细胞,将裂解的样本总蛋白经过1D SDS-PAGE预分离,然后采用17O/16O分别标记两种样本酶切后的多肽混合物.结合纳升级液相色谱(Nano-HPLC-MS/MS)定量地鉴定胃癌细胞和胃黏膜良性上皮细胞的差异表达蛋白.共筛选出78个差异表达蛋白,其中42个蛋白质在胃癌组织中表达上调,36个蛋白质下调.Western blot技术验证了其中几个差异蛋白(moesin,periostin,annexin A2,annexin A4)的表达,与蛋白质组学研究的结果一致.LOM技术结合18O稳定同位素标记的定量蛋白质组学技术,为研究胃癌发生机制、筛选胃癌的分子标志物提供了新的思路,亦为诸如胃癌等复杂体系蛋白质的分离鉴定提供了新的技术选择.     

胶片吸附的激光显微切割技术及其在蛋白质组研究中的应用

组织显微切割在特定细胞亚群的比较研究中起着重要作用.新近发展的胶片吸附激光显微切割技术能从复杂的生物组织中快速准确地分离纯化出特定细胞亚群.在这项技术中,透明的乙烯乙酸乙烯基酯热塑性胶片覆盖于病理组织切片表面,CO₂激光束特异性作用于目的细胞群表面的胶片,胶片对细胞较强的吸附作用使得选择性自动移取目的细胞群成为可能.目前,这项技术已在蛋白质组分析中获得成功应用,并有望对其产生较深远的影响.     

应用激光显微切割技术检测单个结肠细胞的基因表达

目的：探讨检测单个结肠细胞的基因表达的方法。方法：应用激光显微切割技术(1aser micmdissection)从冰冻切片上将单个结肠细胞切下,提取总RNA,将RNA逆转录成cDNA,采用巢式逆转录聚合酶链反应(nested RT—PCR)检测mRNA的表达。结果：在显微镜下用紫外激光显微切割机,将单个结肠细胞成功切下,提取RNA后,逆转录成cDNA,经过巢式RT—PCR扩增后,扩增产物在琼脂糖凝胶上清晰可见。结论：联合应用激光显微切割和巢式RT—PCR可以检测单个结肠细胞的基因表达。     

Laser Capture Microdissection in the Tissue Biorepository

An important need of many cancer research projects is the availability of high-quality, appropriately selected tissue. Tissue biorepositories are organized to collect, process, store, and distribute samples of tumor and normal tissue for further use in fundamental and translational cancer research. This, in turn, provides investigators with an invaluable resource of appropriately examined and characterized tissue specimens and linked patient information. Human tissues, in particular, tumor tissues, are complex structures composed of heterogeneous mixtures of morphologically and functionally distinct cell types. It is essential to analyze specific cell types to identify and define accurately the biologically important processes in pathologic lesions. Laser capture microdissection (LCM) is state-of-the-art technology that provides the scientific community with a rapid and reliable method to isolate a homogeneous population of cells from heterogeneous tissue specimens, thus providing investigators with the ability to analyze DNA, RNA, and protein accurately from pure populations of cells. This is particularly well-suited for tumor cell isolation, which can be captured from complex tissue samples. The combination of LCM and a tissue biorepository offers a comprehensive means by which researchers can use valuable human biospecimens and cutting-edge technology to facilitate basic, translational, and clinical research. This review provides an overview of LCM technology with an emphasis on the applications of LCM in the setting of a tissue biorepository, based on the author''s extensive experience in LCM procedures acquired at Fox Chase Cancer Center and Hollings Cancer Center.     

Laser Capture Microdissection of Drosophila Peripheral Neurons

The dendritic arborization (da) neurons of the Drosophila peripheral nervous system (PNS) provide an excellent model system in which to investigate the molecular mechanisms underlying class-specific dendrite morphogenesis^1,2. To facilitate molecular analyses of class-specific da neuron development, it is vital to obtain these cells in a pure population. Although a range of different cell, and tissue-specific RNA isolation techniques exist for Drosophila cells, including magnetic bead based cell purification^3,4, Fluorescent Activated Cell Sorting (FACS)^5-8, and RNA binding protein based strategies⁹, none of these methods can be readily utilized for isolating single or multiple class-specific Drosophila da neurons with a high degree of spatial precision. Laser Capture Microdissection (LCM) has emerged as an extremely powerful tool that can be used to isolate specific cell types from tissue sections with a high degree of spatial resolution and accuracy. RNA obtained from isolated cells can then be used for analyses including qRT-PCR and microarray expression profiling within a given cell type^10-16. To date, LCM has not been widely applied in the analysis of Drosophila tissues and cells^17,18, including da neurons at the third instar larval stage of development.Here we present our optimized protocol for isolation of Drosophila da neurons using the infrared (IR) class of LCM. This method allows for the capture of single, class-specific or multiple da neurons with high specificity and spatial resolution. Age-matched third instar larvae expressing a UAS-mCD8::GFP¹⁹ transgene under the control of either the class IV da neuron specific ppk-GAL4²⁰ driver or the pan-da neuron specific 21-7-GAL4²¹ driver were used for these experiments. RNA obtained from the isolated da neurons is of very high quality and can be directly used for downstream applications, including qRT-PCR or microarray analyses. Furthermore, this LCM protocol can be readily adapted to capture other Drosophila cell types a various stages of development dependent upon the cell type specific, GAL4-driven expression pattern of GFP.Download video file.^{(137M, mp4)}     

Laser Capture Microdissection of Neurons from Differentiated Human Neuroprogenitor Cells in Culture

Neuroprogenitor cells (NPCs) isolated from the human fetal brain were expanded under proliferative conditions in the presence of epidermal growth factor (EGF) and fibroblast growth factor (FGF) to provide an abundant supply of cells. NPCs were differentiated in the presence of a new combination of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), dibutyryl cAMP (DBC) and retinoic acid on dishes coated with poly-L-lysine and mouse laminin to obtain neuron-rich cultures. NPCs were also differentiated in the absence of neurotrophins, DBC and retinoic acid and in the presence of ciliary neurotrophic factor (CNTF) to yield astrocyte-rich cultures. Differentiated NPCs were characterized by immunofluorescence staining for a panel of neuronal markers including NeuN, synapsin, acetylcholinesterase, synaptophysin and GAP43. Glial fibrillary acidic protein (GFAP) and STAT3, astrocyte markers, were detected in 10-15% of differentiated NPCs. To facilitate cell-type specific molecular characterization, laser capture microdissection was performed to isolate neurons cultured on polyethylene naphthalate (PEN) membrane slides. The methods described in this study provide valuable tools to advance our understanding of the molecular mechanism of neurodegeneration.