Here we describe a procedure based on the use of lentiviral particles for the long-term genetic modification of neural stem cells and/or their adjacent ependymal cells in the adult ventricular-subventricular neurogenic niche which allows the separate analysis of cell autonomous and non-autonomous, niche-dependent effects on neural stem cells.
相对静止的成体干细胞支持在大多数成人组织终身细胞更新。在成年哺乳动物脑的神经干细胞被限制在两个特定神经源性龛:在海马的齿状回和心室脑室下区的颗粒下区(V-SVZ;也称为室管膜下区或SEZ)在横向的壁心室。的成人干细胞群在体内基因转移策略导致干细胞所需的转基因的长期表达和它们的衍生后代的发展(即那些哺乳动物大脑的)是在当前生物医学和生物技术研究的一个重要工具。这里,一个直接的体内方法提出了成年小鼠的V-SVZ细胞的稳定遗传修饰采用由LV的细胞周期无关的感染和V SVZ龛的高度专业化的细胞结构的优势。具体地,目前的协议涉及是空的LV(对照)或LV编码特定基因的表达盒插入相应的V-SVZ本身的注入,对于所有类型的壁龛细胞的体内靶向 ,或进入侧脑室管腔,为室管膜的定位只有细胞。然后表达盒被整合到转导的细胞和荧光蛋白,也被的LV编码的基因组中,允许在检测到转导的细胞的对的细胞中自主和非自主,小生依赖效应的标记的细胞并分析它们的后代。
鼠心室脑室下区(V-SVZ),在面对纹状体侧脑室的壁,是一种非常活跃的生发区域,其中在持久生产嗅球祖细胞复制和分化的结果的一个持续的过程(OB )的interneurons和胼胝体少突胶质细胞1。终身代这些细胞似乎是由在神经干细胞(NSCs;也称为B1细胞)的此区域中的存在来支持,该表达星形细胞抗原胶质纤维酸性蛋白(GFAP)和干细胞标记物如巢蛋白,ID1和Sox2 2。 GFAP表达B1细胞产生的过境放大祖(TAP)细胞(C细胞),表达转录因子DLX2(远端无同源2)和ASCL1(哺乳动物achaete-schute同源物1)和除法迅速几次就会使人产生之前在迁移神经母细胞(A细胞)或oligodendroblasts 3。 prolif新生成erative神经细胞迁移前方,形成喙迁移流(RMS)的OB,在那里他们融入颗粒和肾小球层的分化抑制性。迁移年轻oligodendroblasts移动到CC,在那里他们成为未成熟的NG2阳性细胞继续分裂本地或分化为成熟的少突胶质细胞髓鞘形成1,4。
B1细胞,胎儿放射状胶质细胞获得,留住他们的前辈的拉长和偏光形态和表现出与自己的优势高度专业化的关系。他们跨越室管膜哪些行了心室和血管灌溉V-SVZ利基的网络之间。 multiciliated室管膜细胞之间B1细胞插层的小心尖进程和单一非能动初级纤毛结束,而其基底处理延伸很长的距离接近平面血管丛,在将b灌溉这个利基结局丛毛细血管2,5-8的荒漠和半荒漠层。
从非神经胶质细胞,这也是GFAP +在完整的V-SVZ利基区分B1〜神经干细胞的最可靠的方法是基于整个安装由三维共聚焦显微镜心室侧壁的制剂和它们的分析后免疫染色GFAP标记薄B1-NSC心尖过程,β连环蛋白划定细胞膜,和任一γ微管蛋白作为纤毛基体或乙酰化α微管蛋白的标记物来标记每个纤毛5,8的程度。从室面这些全坐骑观测表明,B1和室管膜细胞被布置在“风车”5,其中一个或几个GFAP + B1细胞的uniciliated根尖过程由multiciliated室管膜细胞的莲座包围。
B1细胞的形态特征与实验相关的证据我ndicating该血管/内皮细胞和心室脑脊液(CSF)构成作用于神经干细胞2,6,9-11可溶性信号调节源。在心室的表面,同型和室管膜参与和B1细胞异型apico侧向相互作用包括紧密连接和粘着路口5,12。此外,在B1和室管膜细胞,如N-钙粘蛋白和V-CAM之间的连接复合牵连粘附分子,已显示出调节不仅B1的高度组织定位在V SVZ小生,而且它们的静止12 13。室管膜-B1细胞单层似乎充当扩散屏障,允许水和小分子从CSF调节的流量,但限制大蛋白10,11的细胞间通道。实验证据表明,独特的定位B1根尖细胞纤毛可以发挥信令存在于CSF 2多肽的传感器的作用,5-7。室管膜细胞本身,也具有在NSC行为14,15的调节作用的可溶性和膜结合信号源。
可追踪核苷,如溴代脱氧尿苷(BrdU)标记,或逆转录病毒已被广泛地用于标记的祖细胞,包括神经干细胞, 在体内 。然而,这些方法不是最佳的长期命运跟踪因为BrdU的信号稀释经过反复的细胞分裂和逆转录病毒似乎优先靶向瞬时放大,由于其为转导16,17的细胞增殖的必要条件的细胞。为了检查体内 NSC生理学,包括与小生组分的相互作用,这是至关重要的,以建立到标签和跟踪很少分裂细胞,如B1〜神经干细胞基本上是静止的和它们相邻室管膜细胞从未生理条件3下分割的方法。这里,我们表明,慢病毒载体(LVS)允许高效率基因标记ING和成人神经干细胞和非分裂室管膜细胞的长期维护,由于最合理其转导,并整合到靶细胞中的细胞周期无关的方式的基因组中的能力。此外,我们显示如何递送和病毒滴度的帮助路由特异性转导室管膜细胞,但不是B1细胞从而允许对神经干细胞生态位依赖性,室管膜影响的分析。
LV的提供超过成人神经干细胞的16,18遗传修饰其他病毒系统的重要优势。到V-SVZ利基立体递送慢病毒的代表一个有效的方法来标记和跟踪不常除以B1-的NSCs克服其他常用的方法,例如BrdU的,这是多种细胞分裂,或逆转录病毒稀释后,只靶细胞的局限这是在应用程序的时刻增殖。的LV,与腺病毒一起,可以独立的其循环状态感染细胞,这是对于那些不循环,如室管膜细胞,或者是相对静止…
The authors have nothing to disclose.
我们承认MJ帕洛普的帮助和技术支持大学去瓦伦西亚SCSIE的。我们也感谢安东尼Follenzi了有益的意见和手稿的讨论。如果这个是由基金会博坦,由桑坦德银行通过其桑坦德大学全球业务部门,并通过从Generalitat瓦伦西亚(Programa PROMETEO,acomp中,与ISIC)和部:EconomìaŸCompetitividad资助项目(MINECO:SAF2011-23331,CIBERNED和网织红细胞雄鹰) 。这项工作也由MINECO 和欧洲研究委员会(ERC)2012年STG BFU2010-21823和网织红细胞雄鹰资助项目(260511- PD-HUMMODEL)到交流 BM-P上。是MINECO的西班牙FPI奖学金的获得者。
Part 1: Generation of LV for in vivo delivery. | |||
Equipment: | |||
Ultracentrifuge | Beckman Coulter | Optima XL-100K | |
Ultracentrifuge rotor | Beckman Coulter | SW-28 | |
Ultracentrifuge rotor | Beckman Coulter | SW-55 | |
Ultracentrifuge tubes | Beckman Coulter | 358126 | 25X89 mm |
Ultracentrifuge tubes | Beckman Coulter | 326819 | 13X51 mm |
Ultracentrifuge adapters | Beckman Coulter | 358156 | |
6-well plate | SPL | PLC-30006 | |
24-well plate | SPL | PLC-30024 | |
10 cm dish | SPL | PLC-20101 | 100×20 style |
FACS tubes | Afora | DE400800 | 12×75 mm, 5 ml |
Cup sterile FACS filter | BD | 340626 | 30 µm |
Nitrocellulose filter | Millipore | SCGPU05RE | 0.22 μm |
Flow cytometer | BD | LSR Fortessa | Blue laser 488 nm |
Steritop filter | Biofil | FPE-204-500 | 0.22 µm |
Reagents: | |||
pMDLg/pRRE plasmid | Addgene | #12251 | Core packaging plasmid |
pRSV.REV plasmid | Addgene | #12253 | Core packaging plasmid |
pMD2G plasmid | Addgene | #12259 | Envelope plasmid |
pRRL-SIN-PPT.PGK.EGFP.Wpre plasmid | Addgene | #12252 | Transfer vector plasmid |
Dulbecco's Modified Eagle's Medium | Biowest | L0101-500 | For HeLa cell culture |
Iscove's Modified Dulbecco's Medium | Life technologies | 12440-053 | For 293T cell culture |
Tris-EDTA (TE) | Tris-HCl (sigma, T5941), 0.1 mM EDTA (sigma, E5134), pH 7.6, DNAse/RNAse-free, 0.2 µm sterile-filtered | ||
2X HBS | 0.28 M NaCl (Sigma, S7653), 0.05 M HEPES (Sigma, H7523), 1.5 mM anhydrous Na2HPO4 (Sigma, S7907) in dH2O (preferably not MilliQ). Adjust pH to 7.0 with NaOH solution (Calbiochem, 567530). | ||
Fetal bovine serum (FBS) | Biowest | S181B-500 | Stock solution at 100X, used to prepare HeLa and 293T culture medium at a final concentration of 10X. |
Glutamine | Sigma-Aldrich | G7513-100 | Stock solution at 200 mM, used to prepare HeLa and 293T culture medium at a final concentration of 6 mM. |
Sodium pyruvate | Life technologies | 11360-039 | Stock solution at 100 mM, used to prepare HeLa and 293T culture medium at a final concentration of 1 mM. |
GlutaMAX Supplement | Life technologies | 35050-061 | Used to prepare 293T culture medium at a final concentration of 1%. |
Penicillin/streptomycin | Sigma-Aldrich | P4458 | Stock solution contains 5,000 units/ml penicillin and 5 mg/ml streptomycin. Used to prepare HeLa and 293T culture medium at a final concentration of 1%. |
Trypsin-EDTA | Life Technologies | 25200-056 | With phenol red, contains 2.5 g porcine trypsin and 0.2 g EDTA 4Na/L HBSS. |
Phosphate buffered saline (PBS) | Sigma-Aldrich | D1408 | Without calcium chloride and magnesium chloride, 10X, liquid, sterile-filtered, suitable for cell culture. Stock solution used to prepare 1X PBS in cell culture grade water. |
Polybrene (hexadimethrine bromide) | Sigma-Aldrich | H9268 | Powder. Prepare a 1000X stock solution at 8 mg/ml in dH2O |
Paraformaldehyde EM grade 16% | EM Sciences | 15710 | |
Name | Company | Catalog Number | Comments |
Part 2: Sterotaxic injection of LV into the SEZ proper or the lateral ventricle. | |||
Equipment: | |||
Vernier stereotaxic instrument | NeuroLab, Leica | 39463001 | |
Cunningham mouse and neonatal rat adaptor | NeuroLab, Leica | 39462950 | |
Syringe holder | KD Scientific | KDS-311-CE | |
33-gauge syringe | Hamilton | P/N 84851/00 | #85RN |
Electric drill | Fine Science Tool | 98096 | |
Thermal blanket | Ufesa | AL5512/01 | 230-240 V, 100-110 W, type C_AL01 |
Shaver | Jata | MP373N | Model: beauty, 3 V, 300 mA, type HT-03. |
Reagents: | |||
Medetomidine | Esteve | DOMTOR | Comercial solution at 1 mg/ml. |
Ketamine | Merial | Imalgene 500 | Comercial solution at 50 mg/ml |
Medetomidina/ketamine mixture | Prepare a working mixture of medetomidine at a final concentration of 0.2 mg/ml dilution and ketamine at a final concentration of 15 mg/ml in saline solution. Use as anesthesia injecting a volume to get a final concentration of 0.5-1 mg medetomidina per kg body weight and 50-75 mg ketamine per kg body weight | ||
Butorphanol | Pfizer | Torbugesic | Stock solution at 10 mg/ml. Used as analgesia at 1 mg/ml in saline solution. |
Atipamezole | Esteve | Antisedan | Stock solution at 5 mg/ml, used in a final concentration of 0.5 mg/ml in saline solution to exit from anesthesia. |
0.9% saline solution | Braun | 13465412 | |
Histoacryl | Braun | 1050052 | Topical skin adhesive |
HydroGel | Clear H2O | 70-01-5022 | |
Kimwipes | Kimberly-Clark | 34120 | 11×21 cm |
Bleach/Virkon | Dupont | ||
Surgical marker pen | Staedler | 313-9 | Permanent lumocolor |
Ophthalmic lubricant | SICCAFLUID | 0.5 g/dosis, carbomer 974P | |
Povidone-iodine | Betadine | 694109.6 | 10% povidone-iodine |
Name | Company | Catalog Number | Comments |
Part 3: Histological analysis. | |||
Equipment: | |||
Automatic peristaltic pump | Cole-Parmer Inst. Co. | HV-07524-55 | Masterflex L/S variable-speed economy drive, 1.6-100 rpm, 230 V |
Pump head | Cole-Parmer Inst. Co. | HV-07518-00 | Masterflex L/S Easy-Load pump head for precision tubing; PSF housing, CRS rotor |
Silicone tube | Cole-Parmer Inst. Co. | HV-96410-16 | Platinum L/S 16 |
Scalp vein set | Vygon V-green | 70246.05T | 25G, 30 cm tube length |
Vibratome | Leica | VT1000 | |
Confocal microscope | Olympus | FluoView FV10i | |
Hot plate | Tehtnica | SHP-10 | |
Reagents: | |||
Phosphate buffer (PB) | 0.2 M PB: 0.2 M Na2HPO4 (Sigma, S7907) and 0.2 M NaH2PO4 (Panreac, 141965.1211) in dH2O, adjust pH to 7.2-7.4 | ||
Paraformaldehyde (PFA) | Panreac | 141451.1211 | Prepare fresh every time. Heat dH2O up to 55–60 °C using a hot plate placed in a fume hood and pour PFA powder while stirring to obtain an 8% solution. The solution is cloudy white as PFA does not dissolve easily. Add 1N NaOH drop by drop just until the solution clears. Cool down, filter through Whatman paper and add an equivalent volume of 0.2 M PB. |
Saline solution | 0.9% NaCl in dH2O | ||
Superglue | LOCTITE | 767547 | |
Sodium azide | Panreac | 122712.1608 | |
Glycine | Sigma-Aldrich | G7126-100 | |
Normal goat serum | Millipore | S30-100 | |
Triton X-100 | Sigma-Aldrich | T9284 | Detergent |
Anti-GFP rabbit antibody | ROCKLAND | 600-401-215 | Use at a 1:500 dilution |
Alexa Fluor 488 Donkey Anti-Rabbit IgG (H+L) Antibody | Molecular probes | A-21206 | Use at a 1:750 dilution |
6-Diamindino-2-phenylindole dihydrochloride hydrate (DAPI) | Sigma-Aldrich | D9542 | Fluorescent nuclear staining. Use at 2 mg/ml in ddH2O. Keep in the dark at 4 °C. |
Fluoromount-G | EM Sciences | 17984-25 | Mounting medium for fluorescent preparations |