慢病毒介导NT-3基因转导神经干细胞体外培养生物学特性研究
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摘要
研究背景和目的:神经干细胞(Neural Stem Cells,NSCs)移植和基因治疗,是治疗缺血性脑血管疾病的两个重要的研究途径。近年来,神经干细胞已经被用作基因治疗的载体,可将治疗基因携带到病灶,通过治疗基因在缺血性损伤局部表达而发挥作用,有望为中风的治疗带来新的希望。本研究的目的:以慢病毒(Lentivirus,LV)介导,将hNT-3基因转入NSCs,并进行体外培养,探讨NSCs-hNT3在体外分化以及表达NT-3时间上的特点,为体内移植NSCs-hNT3的研究和临床应用提供必要的体外实验依据。
     方法:实验共分二部分。第一部分:从孕14天Sprague-Dawley(S-D)大鼠胚胎的脑组织分离出神经干细胞,采用无血清培养法,进行体外培养、扩增,并通过免疫荧光化学染色(巢蛋白)进行鉴定。取传至第5~6代神经干细胞,以1×10~5 cells/500μl/孔接种于24孔板,分别按复感染指数(Multiplicities of infection,MOIs值)为0、1、5、10、15、20加入携带报告基因GFP的慢病毒载体(lentiviralvector-GFP,LV/GFP)稀释液,每一滴度加六孔,共六组。2~3天后于倒置荧光显微镜下观察各组GFP的表达效率,并在3天后进行神经干细胞球进行计数,观察LV/GFP对NSCs增殖的影响。并行流式细胞仪检测,得出各组NSCs的GFP阳性转染率。第二部分:构建表达hNT-3基因的慢病毒载体(lentiviral vector-hNT-3,LV/hNT-3),实验组根据最佳MOI用LV/hNT-3转染NSCs,对照组NSCs不转染病毒。两组细胞继续无血清培养,48h~96h后,应用ELISA和免疫荧光染色方法对两组NSCs在体外的分化和NT-3的表达进行检测。
     结果:第一部分:NSCs以悬浮细胞球方式生长,nestin染色阳性。转染GFP基因后,除MOI值为0的对照组外,2~3天后各孔均有GFP表达。MOI值从0增至10,细胞的阳性表达率逐渐提高(P<0.05),MOI值为10的组能获得>85%的转染率。但MOI值从10增至20,形成的神经干细胞球数目却逐渐减少。第二部分:NT-3修饰的神经干细胞早期跟亲代无形态学区别,3-4天后,实验组中神经干细胞分化比例比对照组明显要高,已分化的细胞在形态上与对照组比较:细胞突起长而且数量多,细胞间突触联系多。转NT-3组神经干细胞,向神经元方向分化的比例明显高于对照组。
     结论:
     1) LV是将外源基因转入神经干细胞的理想载体。以MOI为10的滴度,LV可将外源基因高效转入神经干细胞内。
     2)慢病毒介导转染神经营养素-3基因的神经干细胞体外培养,能高效表达NT-3,向神经元方向分化比例增多,且能形成的突起较长,数量多。
Background and Objective:Neural stem cells(NSCs) transplantation and gene therapy are the most important approaches to novel strategies for ischemic stroke therapy.In recent years,NSCs,for their pathotropism and their longterm persistence in target tissue have,been used as a promising vehicle for targeted gene deliverys.The innate capacity of NSCs to release protective molecules can further be increased by genetically transfecting NSCs to secrete additional neuroprotective peptides or molecules that can play an important role in hypoxic-ischemic brain injury repair and regeneration.Combined gene therapy and NSCs transplanation brings a novel thinking and pathway for ischemic stroke therapy.
     NSCs,transduced by hNT-3 gene mediated by LV,were grown,expended and propagated in serum-free medium.We investigated the optimal MOI of LV.The study observed the expression of NSCs modified by NT-3 gene after transfection,as well as tested the neuronal differentiation under the influence of expression of the neuron-inducing factor,NT-3,by genetically modified NSCs.
     Methods:The study consisted of three parts.PartⅠ:Neural stem cells were extracted from rat embryonic brain(E14),then grown,expended and propagated in serum-free medium.Passage 5~6 neural stem cells were seeded at a density of 1×105/500μl/well in 24-well plates and exposed to lentiviral vector(LV) coding for GFP reporter gene(LV/GFP) at multiplicities of infection(MOIs) of 0,1,5,10,15,20 respectively.There were six groups totally,and each group had six wells seeded.The cells were incubated in a humidified atmosphere with 5%CO2 at 37℃.2~3 days later,the cells were observed under inverted fluorescence microscope.And 3 days later,neurospheres were counted followed by flow cytometer examination to get the percentage of transgene positive NSCs.PartⅡ:The lentiviral vector(LV) coding for Flag-tagged hNT-3(LV/hNT3) gene was constructed by the co-transfection of 293T cells with transfer plasmid coding for hNT-3(pGC-E1/hNT-3) and two help plasmids (pHelper 1.0 and Helper 2.0) using Lipofectamine 2000.NSCs were transduced by hNT-3 gene mediated by LV,grown as partⅠ.Immunofluorencence staining was used to label NSCs-hNT3(MAP2,GFAP,GalC) and newly proliferated cells.The proportion of neuronal differentiation was gotten.We collected the cells and medium at 48h、72h、96h,and observed the expression of NT-3 by ELISA.
     Results:PartⅠ:7~8 days after isolated from rat embryonic brain,NSCs grew as free-floating nestin-positive neurospheres.2~3 days after GFP gene transduction, GFP-expressing cells cound be seen except in the control group,Over 90%cells were GFP-positive at 3 days after transduction by LV at MOI of 10.A significant dose-response was observed with increasing virus titer for MOI 0 to 10(P<0.05), whereas the amount of neurospheres decrease with increased virus load for MOI 10 to 20.PartⅡ:When cultured in serum containing media,NSC-NT3 cells,like the parent NSCs,still differentiated into all three fundamental neural cell types((neurons, astrocytes and oligodendrocytes).However,NSCs-NT3's percentage of neurons was higher than the parent NSCs'.In NSCs-NT3,neuronal differentiation always predominated.The neurons that derived from the NSCs-NT3 cells bore more numerous and longer processes than non-engineered NSCs assayed at the same time in culture.
     Conclusion:
     1) LV is an ideal vector for gene transduction and it can transduce a foreign gene into NSCs with high efficency of over 85%at the MOI of 10.
     2) NSCs-NT3's percentage of neurons is higher than the controls.The neurons that derived from the NSCs-NT3 cells born more numerous and longer processes than non-engineered NSCs.
引文
1. Takabashi J, Palmer JD, Gage FH. Retinoic acid and neurotrophins collaborate to regulate neurogenesis in adult-derived neural stem cell cultures. J Neurobiol, 1999,38(1): 65-81
    2. Muller FJ, Snyder EY, Loring JF, et al.Gene therapyxan neural stem cells deliver? Nat. Rev. Neurosci. 2006,7 : 75-84 [review].
    3. Park KI,. Himes BT, Stieg PE, et al. Neural stem cells may be uniquely suited for combined gene therapy and cell replacement: Evidence from engraftment of Neurotrophin-3-expressing stem cells in hypoxic-ischemic brain injury. Exp Neurol 2006,199:179-190.
    4. Baldauf K, Reymann KG Influence of EGF/bFGF treatment on proliferation,early neurogenesis and infarct volume after transient focal ischemia. Brain Res, 2005,1056:158-167.
    5. Ghosh A, Greenberg ME. Distinct roles for bFGF and NT-3 in the regulation of cortical neurogenesis. Neuron, 1995,15:89-103.
    6. Vicario-Abejon C, Johe KK, Hazel TG, Collazo D, McKay RD. Functions of basic fibroblast growth factor and neurotrophins in the differentiation of hippocampal neurons. Neuron, 1995,15:105-114.
    7. Dempsey RJ, Sailor KA, Bowen KK, Tureyen K, Vemuganti R. Stroke-induced progenitor cell proliferation in adult spontaneously hypertensive rat brain:effect of exogenous IGF-1 and GDNF. Neurochem, 2003, 87:586-597.
    8. Chu K,Park KI,Lee ST,et al.Combined treatment of vascular endotheliar grouth factor and human neural stem cells in experimental focal cerebral ischemia.Neurosci Res, 2005, 84-390.
    9. Zhou L, Ma W, Yang Z,et al. VEGF165 and angiopoietin-1 decreased myocardium infarct size through phosphatidylinositol-3 kinase and Bcl-2 pathways. Gene Ther, 2005,12:196-202.
    10. Pyle AD, Lock LF, Donovan PJ. Neurotrophins mediate human embryonic stem cell surval. Nat Biotechnol, 2006,24:344-350.
    11. Ghosh A, Greenberg ME. Distinct roles for bFGF and NT-3 in the regulation of cortical neurogenesis. Neuron, 1995,15:89-103.
    12. Vicario-Abejon C, Johe KK, Hazel TG, Collazo D, McKay RD. Functions of basic fibroblast growth factor and neurotrophins in the differentiation of hippocampal neurons.Neuron,1995,15:105-114.
    13.Hossain WA,Brumwell CL,Morest DK.Sequential interactions of fibro blast growth factor-2,brain-derived neurotrophic factor,neurotrophin-3,and their receptors define critical periods in the development of cochlear ganglion cells.Exp Neurol,2002,175:138-151
    14.Aletsee C,Brors D,Mlynski R,et al.Wortmannin,a specific inhibitor of phosphatidylinostol-3-kinase influences neurotrophin induced spiral ganglion neurite growth.Laryngorhi-nootologie.2002,81:189-195
    15.Yamauchi J,Chan JR,Shooter EM.Neurotrophin 3 activation of TrkC induces Schwann cell migration through the c-Jun N-terminal kinase pathway.Proc.Nail Acad Sci,2003,100:14421-14426.
    16.Pettingill LN,Minter RL,Shepherd RK.Schwann cells genetically modified to express neurotrophins promote spiral ganglion neuron surviral in vitro.Neuroscience,2008,152:821-828
    17.Kook In Park,B.Timothy Himes,Philip E.Stieg,Alan Tessler,et al.Neural stem cells may be uniquely suited for combined gene therapy and cell replacement:Evidence from engraftment of Neurotrophin-3-expressing stem cells in hypoxic-ischemic brain injury.Experimental Neurology.2006,199:179-190.
    18.Imren S,Fabry ME,Westerman KA,et al.High-level β-globin expression and preferred intragenic integration after lentiviral transduction of human cord blood stem cells.J Clin Invest,2004,114:953-962.
    19.Vroemen M,Weidner N,Blesch A.Loss of gene expression in lentivirus- and retrovirus- transduced neural progenitor cells is correlated to migration and differentiation in the adult spinal cord.Exp Neurol,2005,195:127-139.
    1. Martono C, Pluchino S. The therapeutic potential of neural stem cells. Natute Review/Neuroscience, 2006, 5, 7:395-406.
    2. Muller F J, Snyder E Y, Loring J,F. Gene therapy: can neural stem cells deliver? Natute Review/Neuroscience, 2006, 8,7:75-84.
    
    3. Wei L, Cui T L, Snider B J,et al. Transplantation of embryonic stem cells over-expressing Bcl-2 promotes functional recovery after transient cerebral ischemia. Neurobiology of Disease, 2005,19 :183- 193.
    
    4. Pineda JR, Rubio N, Akerud P,et al. Neuroprotection by GDNF-secreting stem cells in a Huntington's disease model: optical neuroimage tracking of brain-grafted cells. Gene Therapy, 2007, 14:118-128.
    5. Gage FH.Mammalian neural stem cells.Science,2000,287:1433-1438.
    6. Park K I, Himes B T, Stieg P E,et al.Neural stem cells may be uniquely suited for combined gene therapy and cell replacement: Evidence from engraftment of Neurotrophin-3-expressing stem cells in hypoxic-ischemic brain injury. Experimental Neurology, 2006,199 :179-190.
    7. McMahon JM,Conroy S,Lyons M,et al. Gene Transfer into Rat Mesenchymal Stem Cells: A Comparative Study of Viral and Nonviral Vectors. Stem Cells and Development ,2006,15,1: 87-96.
    8.TronoD.Lentiviral vectors:turning a deadly foe into a therapeutic agent.Gene Therapy,2000,7:20-23.
    9. Perrier AL,Tabar V,Barberi T,et al. Derivation of midbrain dopamine neurons from human embryonic stem cells. Proc. Natl Acad. Sci. USA, 2004 101:12543-12548.
    10. Lindvall O, Kokaia Z. Stem cells for the treatment of neurological disorders. Nature, 2006, 441:1094-1096.
    1.Park K I,Himes B T,Stieg P E,et al.Neural stem cells may be uniquely suited for combined gene therapy and cell replacement:Evidence from engraftment of Neurotrophin-3-expressing stem cells in hypoxic-ischemic brain injury.Experimental Neurology,2006,199:179-190.
    2.Dicou,E.Peptides other than the neurotrophins that can be cleaved from proneurotrophins:a neglected story.Arch Physiol Biochem,2007,113(4-5):228-33.
    3.Lykissas,M.G.and A.K.Batistatou,et al.The role of neurotrophins in axonal growth,guidance,and regeneration.Curr Neurovasc Res,2007,4(2):143-51.
    4.Lisa N Gillespie.Regulation of axonal growth and guidance by the neurotrophin family of neurotrophinc factors.Clinical and Experimental Pharmacology and physiology,2003,30:724-733
    5.Yamauchi J,Chan JR,Shooter EM.Neurotrophin 3 activation of TrkC induces Schwann cell migration through the c-Jun N-terminal kinase pathway.Proc.Natl Acad Sci,2003,100:14421-14426
    6.Pettingill LN,Minter RL,Shepherd RK.Schwann cells genetically modified to express neurotrophins promote spiral ganglion neuron surviral in vitro.Neuroscience,2008,152:821-828.
    7.郭家松,曾园山,等.NT-3基因修饰施万细胞与神经干细胞联合移植治疗全横断脊髓损伤的实验研究.解剖学报.2004,34(5):466
    1.Das I.TrakC signaling is required for retinal progenitor cell proliferation.J Neuroscience,2000,20(8):2887-2895
    2.Gavazzi I.Growth response of different subpopulations of adult sensory neurons to neurotrophic factors in vitro.J Nwuroscience,2000,11(10):3405-3414
    3.Aleiandro F Schinder S,MuMing Poo.Neurotrophin hypothesis for synaptic plasticity.J TINS,2000,23(12):639-645
    4.Hossain WA,Brumwell CL,Morest DK.Sequential interactions of fibro blast growth factor-2,brain-derived neurotrophic factor,neurotrophin-3,and their receptors define critical periods in the development of cochlear ganglion cells.Exp Neurol,2002,175:138-151
    5.Leibrock J,Lottspeich F,Hohn A,et al.Molecular cloning and expression of brain-derived neurotrophic factor.Nature,1989,341(6237):149-152
    6.Kevin RJ,Louis FR.Molecular cloning of a human gene that is a member of the nerve growth factor family.Proc Natl Acad Sci USA.1990,87:8060-8064
    7.Cotz R,Koster R,Winkel C,et al.Neurotrophin 6 is a new member of the nerve growth factor family.Nature,1994.372:266-269
    8.Irina V.Nosrat,Sven Lindskog,Ake.Seiger et al.Lingual BDNF and NT-3mRNA expression patterns and their relation to innervation in the human tongue:similarities and differences compared with Rodents.J Comp Neural,2000,417:133
    9.郭雨霁,李盛芳.神经营养因子家族及其受体的研究进展.神经解剖学杂志,2001,17(3):288-294
    10.Reichardt,L.F.Neurotrophin-regnlated signalling pathways.Philos Trans R Soc Lond B Biol Sci,2006 361(1473):1545-64
    11.郭家松,曾园山,李海标,等.神经干细胞与NT-3基因修饰雪旺细胞联合移植促进全横断脊髓损伤大鼠功能修复的实验研究[J].中国康复医学杂志,2005,20(5):4-6
    12.Lykissas,M.G.and A.K.Batistatou,et al.The role of neurotrophins in axonal growth,guidance,and regeneration.Curr Neurovasc Res,2007,4(2):143-51.
    13.Lisa N Gillespie.Regulation of axonal growth and guidance by the neurotrophin family of neurotrophinc factors.Clinical and Experimental Pharmacology and physiology,2003,30:724-733.
    14.Ramer MS,Duraisingam I.Priestley JV,et al.Two-tiered inhibition of axon regeneration at dorsal root entry zone.J Neurosci,2001,21(8):2651-2660.
    15.Dicou,E.Peptides other than the neurotrophins that can be cleaved from proneurotrophins:a neglected story.Arch Physiol Biochem,2007,113(4-5):228-33.
    16.Castellanos RA,Tsoulfas P,Frydel BR,et al.TrkC overexpression enhances survival and migration of neural stem cells transplants in the rat spinal cord.Cell Transplant,2002,11(3):297-307
    17.Liu Y,Himes BT,Solowska J,et al.Intraspinal delivery of neurotrophin-3 using neural stem cells genetically modified by recombinant retrovirus[J].Exp Neurol,1999,158(1):9-26
    18.Vicario-Abejon C,Collin C,Tsoulfas P,et al.Hippocampus stem cells differentiate into excitatory and inhibitory neurons[J].Eur J Neurosci,2000,12(2):677-688.
    19.Lu P,Jones LL,Snyder EY,et al.Neural stem cells constitutively secrete neurotrophic factors and promote extensive host axonal growth after spinal cord injury[J].2003,181(2):115-129
    20.Zhang L,Gu S,Zhao C,et al.Combined treatment of neurotrophin-3 gene and neural stem cells is propitious to functional recovery after spinal cord injury[J].Cell Transplant,2007,16(5):475-481.
    21.Tsai,-E-C,Dalton,-P-D,Shoichet,-M-S,Tator,-C-H.Matrix inclusion within synthetic hydrogel guidance channels improves specific supraspinal and local axonal regeneration after complete spinal cord transection.Biomaterials.2006 Jan;27(3):519-33
    22.王德华,徐建光,姜浩,等.神经干细胞移植再支配失神经骨骼肌的实验研究.中华手外科杂志.2004,20:96-99.
    23.林森,徐建光,胡韶楠,等.神经营养因子-3诱导大鼠脊髓神经干细胞分化为胆碱能神经元的实验研究.中华创伤骨科杂志.2007,9(6):546-549.
    24.Kook In Park,B.Timothy Himes,Philip E.Stieg,Alan Tessler,et al.Neural stem cells may be uniquely suited for combined gene therapy and cell replacement:Evidence from engraftment of Nenrotrophin-3-expressing stem cells in hypoxic-ischemic brain injury.Experimental Neurology.2006,199:179-190.
    25.Bates B,Hirt L,Thomass SS,et al.Neurotrophin-3 promotes cell death induced in cerebral ischemia,oxygen-glucose deprivation,and oxidative stress:possible involvement of oxygen free radicals.Neurobiol Dis,2002,9(1):24-37.
    26.Schindowski,K.and K.Belarbi,et al.Neurotrophie factors in Alzheimer's disease:role of axonal transport.Genes Brain Behav.20087 Suppl 1:43-56.

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