Rapid Transgene Expression in Multiple Precursor Cell Types of Adult Rat Subventricular Zone Mediated by Adeno-Associated Type 1 Vectors
Rapid Transgene Expression in Multiple Precursor Cell Types of Adult Rat Subventricular Zone Mediated by Adeno-Associated Type 1 Vectors
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DOI：
10.1089/hum.2011.216
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发表时间：
2012-07-01
影响因子：
4.2
通讯作者：
Tenenbaum, Liliane
中科院分区：
文献类型：
--
作者：
Bockstael, Olivier;Melas, Catherine;Tenenbaum, Liliane
成年大鼠脑室下区（SVZ）含有增殖的前体细胞，这些前体细胞迁移到嗅球（OB）并分化为成熟的神经元。前体的招募构成了大脑修复的潜在途径。我们已经研究了由AAV 2/1载体介导的转基因表达的动力学和细胞特异性（即，用AAV 1衣壳假型化的腺相关病毒2型）。自身互补（sc）和单链（ss）AAV 2/1载体分别在注射后17和24小时介导有效的GFP表达。转基因表达在所有快速增殖的细胞类型中都是有效的，即Mash 1（+）前体细胞（30%的GFP（+）细胞）、Dlx 2（+）神经元祖细胞（55%）、Olig 2（+）少突胶质细胞祖细胞（35%）和双皮质素阳性（Dcx（+））迁移细胞（40%），而在缓慢增殖的胶质细胞酸性蛋白阳性（GFAP（+））神经干细胞池中（5%）则没有。因为在原代培养中已经描述了野生型和重组AAV引起的细胞周期阻滞，所以我们检测了载体注射后SVZ的增殖活性。事实上，细胞增殖在载体注射后立即降低，但在1个月后正常。相反，GFP（+）前体的迁移和分化没有改变。事实上，Dcx（+）细胞的比例在注射的半球和对侧半球是相似的。此外，在载体注射到SVZ后1个月，如预期的那样，在OB颗粒细胞层中发现GFP（+）细胞是成熟的GABA能神经元。总之，由scAAV 2/1载体介导的SVZ神经前体中的快速和有效的转基因表达强调了它们通过募集未成熟细胞用于脑修复的潜在有用性。观察到的短暂前体增殖抑制，不影响其迁移和分化，可能不会损害这种策略。
The adult rat brain subventricular zone (SVZ) contains proliferative precursors that migrate to the olfactory bulb (OB) and differentiate into mature neurons. Recruitment of precursors constitutes a potential avenue for brain repair. We have investigated the kinetics and cellular specificity of transgene expression mediated by AAV2/1 vectors (i.e., adeno-associated virus type 2 pseudotyped with AAV1 capsid) in the SVZ. Self-complementary (sc) and single-stranded (ss) AAV2/1 vectors mediated efficient GFP expression, respectively, at 17 and 24 hr postinjection. Transgene expression was efficient in all the rapidly proliferating cells types, that is, Mash1(+) precursors (30% of the GFP(+) cells), Dlx2(+) neuronal progenitors (55%), Olig2(+) oligodendrocyte progenitors (35%), and doublecortin-positive (Dcx(+)) migrating cells (40%), but not in the slowly proliferating glial fibrillary acidic protein-positive (GFAP(+)) neural stem cell pool (5%). Because cell cycle arrest by wild-type and recombinant AAV has been described in primary cultures, we examined SVZ proliferative activity after vector injection. Indeed, cell proliferation was reduced immediately after vector injection but was normal after 1 month. In contrast, migration and differentiation of GFP(+) precursors were unaltered. Indeed, the proportion of Dcx(+) cells was similar in the injected and contralateral hemispheres. Furthermore, 1 month after vector injection into the SVZ, GFP(+) cells, found, as expected, in the OB granular cell layer, were mature GABAergic neurons. In conclusion, the rapid and efficient transgene expression in SVZ neural precursors mediated by scAAV2/1 vectors underlines their potential usefulness for brain repair via recruitment of immature cells. The observed transient precursor proliferation inhibition, not affecting their migration and differentiation, will likely not compromise this strategy.