Summary

一个的趋电含量为神经前体细胞迁移的动力学分析外部施加直流电场

Published: October 13, 2012
doi:

Summary

在这个协议中,我们将演示如何构建自定义室,允许应用程序的直流电场,使时间的推移成像的成人脑源性神经前体细胞转趋电性。

Abstract

神经干细胞和祖细胞(统称为神经前体细胞)(的NPC)在成年哺乳动物大脑的发现已导致一个机构的研究,目的是在利用这些细胞的多能和增殖特性的发展的神经再生策略。这种战略成功的一个关键步骤是动员的NPC外源性移植后向病变部位或提高内源性的前体,发现脑室周围白质区域的中枢神经系统的反应。因此,有必要了解的机制,促进,引导,增强人大迁移。我们的工作主要集中在利用直流电场(量增多),以促进和直接的NPC迁移 – 这种现象被称为趋电性。内源性生理电场的正常发育和伤口修复细胞迁移过程中发挥作用的关键线索。药理中断在蝾螈胚胎的的跨神经管潜力会导致严重的发育畸形。的速度修复受伤的角膜伤口愈合的情况下,直接与上皮损伤后产生的伤害潜力的幅度,药理增强或中断,这DCEF 2-3所示。我们已经证明,成年室管膜下的NPC进行快速和导演的阴极迁移的影响 ,当暴露在外部施加的dcEF。在这个协议中,我们将介绍创建一个简单而有效的高分辨率,长期观察的细胞体易位(迁移)在单细胞水平的趋电检测实验室的技术。该测定中,将适合于调查机制调节dcEF转导到细胞运动通过使用转基因或基因敲除小鼠,短干扰RNA,或特定的受体激动剂/拮抗剂。

Protocol

多伦多大学的动物保健委员会批准了在所有涉及动物处理的程序,按照制度指引(协议。20009387)。应当执行下面的方法,使用无菌的工具和技术,在层流罩(如适用)。 在下面的协议文本中,短语“EFH-SFM”是指以与表皮生长因子,碱性成纤维细胞生长因子和肝素的无血清培养基中。 EFH-SFM调查时,未分化的NPC,因为这些有丝分裂原的趋电维持其未分化状态的NPC 4。?…

Representative Results

运动学分析表明,在250毫伏/毫米dcEF的存在下,未分化的NPC表现出高度定向和快速的趋电向阴极( 图5A,电影1)。在一个dcEF缺席,随机运动的细胞中观察到( 图5B,电影2)。在此输入强度,> 98%的未分化的NPC迁移整个6-8小时,这是他们的成像,并自死细胞不迁移,这表明,它们在此期间,在存在或不存在的dcEF仍然可行。 有区别的表型进行可以忽…

Discussion

该协议已经进行了调整,从以前的研究7-9的行之有效的方法。可以使用各种不同的技术,包括建造一个单独的玻璃以及禁闭细胞接种中部槽10,11的微细化,或使用CO 2激光烧蚀构造galvanotactic室。有些技术可能比别人更费力,代价高昂的。我们描述了一个简单和成本效益的分析,为构建全国人民代表大会趋电性室使用的材料通常存在于大多数细胞生物学实验室。我们的协议,…

Disclosures

The authors have nothing to disclose.

Acknowledgements

这项工作的经费由自然科学和工程研究理事会,加拿大(拨款#249669,#482986)和加拿大心脏及中风基金会(拨款#485508)。作者感谢优素福埃尔 – 哈耶克和博士齐哇嗯为他们的协助开发实验的协议。

Materials

Name of item Company Catalogue number Comments
Neural Precursor Cell Isolation
2M NaCl Sigma S5886 11.688 g dissolved in 100 ml dH2O
1M KCl Sigma P5405 7.456 g dissolved in 100 ml dH2O
1M MgCl2 Sigma M2393 20.33 g dissolved in 100 ml dH2O
155 mM NaHCO3 Sigma S5761 1.302 g dissolved in 100 ml dH2O
0.5M Glucose Sigma G6152 9.01 g dissolved in 100 ml dH2O
108 mM CaCl2 Sigma C7902 1.59 g dissolved in 100 ml dH2O
Penicillin-streptomycin Gibco 15070
Bovine pancreas trypsin Sigma T1005
Sheep testes hyaluronidase Sigma H6254
Kynurenic acid Sigma K3375
Ovomucoid trypsin inhibitor Worthington LS003086
DMEM Invitrogen 12100046
F12 Invitrogen 21700075
30% Glucose Sigma G6152
7.5% NaHCO3 Sigma S5761
1M HEPES Sigma H3375 23.83 g dissolved in 100 ml dH2O
L-glutamine Gibco 25030
EGF Invitrogen PMG8041 Reconstitute in 1 ml of hormone mix and aliquot into 20 μl units.
FGF Invitrogen PHG0226 Reconstitute in 0.5 ml of hormone mix and aliquot into 20 μl units.
Heparin Sigma H3149
Apo-transferrin R&D Systems 3188-AT 0.1 g dissolved into 4 ml dH20
Putrescine Sigma P7505 Dissolve 9.61 mg into Apo-transferrin solution
Insulin Sigma I5500 Dissolve 25 mg into 0.5 ml of 0.1N HCl and add to 3.5 ml of dH20
Selenium Sigma S9133
Progesterone Sigma P6149
Standard Dissection Tools Fine Science Tools
Dissection microscope Zeiss Stemi 2000
Galvanotaxis Chamber Preparation
Square glass cover slides VWR 16004
6N Hydrochloric Acid VWR BDH3204-1
High vacuum grease Dow Corning
60 mm Petri dishes Fisher Scientific 0875713A
Poly-L-lysine Sigma P4707
Matrigel BD Biosciences 354234 Thaw and aliquot into 150 μl units
FBS Invitrogen 10082139 Only use if inducing NPC differentiation, otherwise use SFM + EFH culture media as indicated above
Counting microscope Olympus CKX41
Live Cell Time-Lapse Imaging
Silver wire Alfa Aesar 11434
UltraPure Agarose Invitrogen 15510-027
Heat Inactivated FBS Sigma 16140071
PVC tubing Fisher Scientific 80000006 3/32″ID x 5/32″OD
Bleach Clorox
10 cc syringe BD 309604
18 gauge needle BD 305195
Dremel drill Dremel Model 750
Inverted microscope equipped with humidified, incubated chamber Zeiss Axiovert-200M

Recipes

Item Volume
2M NaCl 6.2 ml
1M KCl 0.5 ml
1M MgCl2 0.32 ml
155mM NaHCO3 16.9 ml
1M Glucose 1 ml
108 mM CaCl2 0.09256 ml
Penicillin-streptomycin 1 ml
Autoclaved water 74 ml

Artificial cerebrospinal fluid

Item Volume or Mass
Artificial cerebrospinal fluid 30 ml
Bovine pancreas trypsin 40 mg
Sheep testes hyaluronidase 22.8 mg
Kynurenic acid 5 mg

Trypsin Solution

Item Volume or Mass
SFM 15 ml
Ovomucoid trypsin inhibitor 10 mg

Trypsin Inhibitor Solution

Item Volume
Autoclaved water 37 ml
10X DMEM/F12 10 ml
30% Glucose 2 ml
7.5% NaHCO3 1.5 ml
1M HEPES 0.5 ml
Transferrin, Putrescine solution 4 ml
25 mg insulin solution 4 ml
Selenium 100 μl
Progesterone 100 μl

Hormone Mix (100 ml total, store at -20 °C)

Item Volume
Autoclaved water 37.5 ml
10X DMEM/F12 (3:1) 5 ml
30% Glucose 1 ml
7.5% NaHCO3 0.75 ml
1M HEPES 0.25 ml
Hormone mix 5 ml
L-glutamine 0.5 ml
Penicillin-streptomycin 0.5 ml

Serum Free Media EFH-SFM: add 10 μl of EGF, 10 μl of FGF, and 3.66 μl of Heparin FBS-SFM: add 0.5 ml FBS

Item Volume
Matrigel 150 μl
SFM 3.6 ml

Matrigel Solution Matrigel aliquot should be placed in a box of ice and allowed to thaw slowly over 4-5 hours to form a viscous liquid before mixing with SFM. This will ensure the formation of a smooth layer of Matrigel substrate. If not thawed slowly, the resulting substrate will contain clumps of Matrigel, possibly hindering cell migration.

Item Volume or Mass
UltraPure Agarose 300 mg in 10 ml ddH20
SFM
Heat Inactivated FBS
8 ml
2 ml

Matrigel Solution Mix 8 ml of SFM with 2 ml heat inactivated FBS in a 15 cc falcon tube. Mix agarose with 10 ml ddH20 in an Erlenmeyer flask, and heat in a microwave for 30 sec in 10-sec intervals, ensuring to remove the solution from the microwave after each 10-sec interval and thoroughly mix. Following the final 10-sec microwave period, mix the agarose solution with the SFM/FBS solution and store in a 57 °C water bath.

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Cite This Article
Babona-Pilipos, R., Popovic, M. R., Morshead, C. M. A Galvanotaxis Assay for Analysis of Neural Precursor Cell Migration Kinetics in an Externally Applied Direct Current Electric Field. J. Vis. Exp. (68), e4193, doi:10.3791/4193 (2012).

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