Differentiation and neurological benefit of the mesenchymal stem cells transplanted into the rat brain following intracerebral hemorrhage

Spontaneous intracerebral hemorrhage (ICH) is often a fatal event. In a patient who survives the initial ictus, the resulting hematoma within brain parenchyma can trigger a series of events that lead to secondary insults and severe neurological deficits. Great efforts have been focused on searching for new approaches to help patients recover neurological function after ICH. Previous studies indicate that mesenchymal stem cells (MSCs) grafted into the ischemic rat brain can improve neurological function. However, there is no report regarding whether MSCs can be used in the same way to improve the neurological function after ICH. We generated the ICH model by injecting collagenase VII into rat brain. Subsequently, 5-bromo-2-deoxyuridine (BrdU)-labeled mesenchymal stem cells were delivered into the brain through carotid artery, cervical vein or lateral ventricle. The distribution and differentiation of MSCs were investigated by methods of immunohistochemistry. We found that MSCs were able to differentiate into neural cells in vitro as well as in the rat brain after ICH. The injected MSCs were able to migrate into hippocampus, blooding foci and ipsilateral cortex. In the hippocampus, MSCs differentiated into neurons; but in surrounding bleeding foci, they differentiated into neurons and astrocytes. In the ipsilateral cortex, MSCs differentiated into neurons, astrocytes and oligodendrocytes. Notably, the motor function of the rats in the carotid artery (CA) group and the lateral ventricle (LV) group improved significantly. Collectively, our study indicates that MSCs are able to differentiate into neural cells in the rat brain after ICH and can significantly improve motor function.     

骨髓基质细胞源神经干细胞移植对脑出血大鼠行为及神经细胞凋亡的动态影响

目的 探讨骨髓基质细胞源神经干细胞对实验性脑出血大鼠行为及神经细胞凋亡的影响.方法 采用自体血注入法建立大鼠脑出血模型.32只健康Sprague-Dawley(SD)大鼠分为假手术组、出血对照组、出血骨髓基质细胞移植组和出血骨髓基质细胞源神经干细胞移植组.分别于移植后1d、7d、14d对大鼠进行神经功能缺损评分和空间学习能力检测,并在移植后7d和14d,分别应用TUNEL法检测神经细胞凋亡.结果 移植后7d各组神经功能均有不同程度的恢复(P<0.05),BMSCs源神经干细胞移植组大鼠的神经功能评分显著优于BMSCs移植组(P<0.01).移植7d后可提高大鼠空间学习能力,且各时间点BMSCs源神经干细胞移植组的空间学习能力改善优于BMSCs组(P<0.05).BMSCs源神经干细胞移植组出血边缘区凋亡细胞数明显少于BMSCs移植(P<0.05).结论 骨髓基质细胞源神经干细胞移植可改善脑出血大鼠神经行为,减少神经细胞凋亡,显著优于BMSCs移植.

Abstract：

Objective To study the effects of bone marrow stromal cells ( BMSCs) derived neural stem cells on behavior and celluar apoptosis in experimental intracerebral hemorrhage (ICH) . Methods The model was established by ster-otactic infusing autologous caudate artery blood into right nucleus caudatus of SD rats. 32 Sprague-Dawley rats were divided into sham-operated group,ICH control group,BMSCs transplanted group and BMSCs derived neural stem cells transplanted group. The neurogenic behavior of the rats were evaluated on 1,7,14 days after transplantation. The rats were killed separat-edly on 7,14days after transplantation. The brain sections were used for TUNEL staining. Result The neurological function of rats were recovery on 7 days later after transplantation( P < 0. 05 ) . The recovery of neurological function in BMSCs derived neural stem cells transplantation group was much evidentl than BMSCs transplantation group( P < 0. 01). The abilities of spatial learning and memory of rats on 7 days later after transplantation got improved (P < 0. 05). More satisfactory outcome got in BMSCs derived neural stem cells transplanted group than in BMSCs transplanted group ( P < 0. 05 ) . The number of apoptotic cells in the group of BMSCs derived neural stem cells transplanted group decreased evidently compared with that of the BMSCs transplantation group (P <0.05). Conclusion BMSCs derived neural stem cells may make the neurogenic behavior recovery, and decrease the infarct volumes and the number of apoptotic cells in ICH.     

大鼠胚胎神经干细胞移植治疗脑出血的实验研究

目的 研究大鼠胚胎神经干细胞移植治疗脑出血的可行性。方法 从孕龄16天的大鼠胚胎脑组织中分离、培养神经干细胞并诱导其分化，通过免疫组化学技术研究其特性。制作大鼠脑出血模型，3天后将未分化的神经干细胞注入血肿同侧或对侧的尾状核内，记录损伤和移植后的大鼠运动功能。不同时间杀死大鼠，研究移植后的干细胞在体内分化和迁徙的情况。结果 实验中分离、培养的神经干细胞体外能够被诱导分化成神经元、光突胶质细胞和星形胶质细胞，血肿同侧移植干细胞的大鼠运动功能的改善显著好于血肿对侧移植干细胞组及未移植干细胞的对照组。免疫组化方法证实移植后的干细胞在体内可分化成神经元和胶质细胞，并向损伤区域迁徙。结论 大鼠胚胎神经干细胞体内、体外均具有多向分化潜能，其分化成各种类型神经细胞的比例与所处的外界环境有关，在脑内靠近损伤部位移植胚胎神经干细胞后能够有效改善脑出血动物的运动功能。     

Transplantation of embryonic stem cells overexpressing Bcl-2 promotes functional recovery after transient cerebral ischemia

The study tested the hypothesis that transplantation of embryonic stem (ES) cells into rat cortex after a severe focal ischemia would promote structural repair and functional recovery. Overexpression of the human anti-apoptotic gene bcl-2 in ES cells was tested for increasing survival and differentiation of transplanted cells and promoting functional benefits. Mouse ES cells, pretreated with retinoic acid to induce differentiation down neural lineages, were transplanted into the post-infarct brain cavity of adult rats 7 days after 2-h occlusion of the middle cerebral artery (MCA). Over 1-8 weeks after transplantation, the lesion cavity filled with ES cell-derived cells that expressed markers for neurons, astrocytes, oligodendrocytes, and endothelial cells. ES cell-derived neurons exhibited dendrite outgrowth and formed a neuropil. ES cell-transplanted animals exhibited enhanced functional recovery on neurological and behavioral tests, compared to control animals injected with adult mouse cortical cells or vehicle. Furthermore, transplantation with ES cells overexpressing Bcl-2 further increased the survival of transplanted ES cells, neuronal differentiation, and functional outcome. This study supports that ES cell transplantation and gene modification may have values for enhancing recovery after stroke.     

Human fetal neural stem cells grafted into contusion-injured rat spinal cords improve behavior

Grafted human neural stem cells (hNSCs) may help to alleviate functional deficits resulting from spinal cord injury by bridging gaps, replacing lost neurons or oligodendrocytes, and providing neurotrophic factors. Previously, we showed that primed hNSCs differentiated into cholinergic neurons in an intact spinal cord. In this study, we tested the fate of hNSCs transplanted into a spinal cord T10 contusion injury model. When grafted into injured spinal cords of adult male rats on either the same day or 3 or 9 days after a moderate contusion injury, both primed and unprimed hNSCs survived for 3 months postengraftment only in animals that received grafts at 9 days postinjury. Histological analyses revealed that primed hNSCs tended to survive better and differentiated at higher rates into neurons and oligodendrocytes than did unprimed counterparts. Furthermore, only primed cells gave rise to cholinergic neurons. Animals receiving primed hNSC grafts on the ninth day postcontusion improved trunk stability, as determined by rearing activity measurements 3 months after grafting. This study indicates that human neural stem cell fate determination in vivo is influenced by the predifferentiation stage of stem cells prior to grafting. Furthermore, stem cell-mediated facilitation of functional improvement depends on the timing of transplantation after injury, the grafting sites, and the survival of newly differentiated neurons and oligodendrocytes.     

Isolation of neural stem cells from the forebrain of deceased early postnatal and adult rats with protracted post-mortem intervals

Neural stem cells were isolated from deceased early postnatal and adult rats with varying post-mortem intervals. Animals were killed by deep anesthesia and stored in a refrigerator at 4 degrees C for 1-6 days before use. Neurospheres were obtained from the forebrain tissue, including the lateral ventricle in the early postnatal rats, and from the striatal wall of lateral ventricle, including the subventricular zone (SVZ) in adult rats. The number of neurospheres obtained in the primary culture from early postnatal animals was much larger than that from the adult rats. There was no significant difference in the population of neurospheres between the living and the deceased animals at least within 2 days after death. A few neurospheres were still obtainable at 6 days after death in early postnatal animals, but almost no neurospheres were obtained at 5 days after death in the adult rats. The differentiation capacity of neural stem cells in neurospheres was similar between the deceased and the living animals. The rich vascular bed in the SVZ of the lateral ventricle suggests that the vascular architecture might be in part responsible for the survival of the neural stem cells in the deceased animals. Neurosphere cells derived from deceased adult rats survived and differentiated mainly into glial cells in the host spinal cord tissue after transplantation into the injured spinal cord. Therefore, the neural stem cells from deceased animals express the same phenotypes as those from living animals in terms of neurosphere formation, proliferation, and differentiation at least 2 days after death. The neural stem cells from cadavers have great significance in terms of their clinical use as homografts for CNS regeneration.     

骨髓间充质干细胞移植治疗脑出血大鼠的实验研究

目的探讨骨髓间充质干细胞移植对脑出血大鼠的行为和血肿周围神经细胞凋亡的影响。方法全骨髓贴壁法分离培养大鼠骨髓间充质干细胞,使用立体定向纹状体注入胶原酶法制作大鼠脑出血模型。SD大鼠30只,随机分为对照组和移植组(各15只),对照组制作脑出血模型,不移植;移植组制作脑出血模型并于造模后48 h经立体定向脑内注射1×105个干细胞,并于移植后1 d、3 d、5 d、7 d、14 d进行神经功能缺损评分,对照组在相应时间点同样评分,各组再根据时间的不同随机分成五个亚组(每组3只),在相应时间点处死大鼠行免疫组织化学法检测细胞凋亡。结果在移植后1 d、3 d,两组大鼠评分及血肿周围脑组织内凋亡细胞的数量均较高,两组之间无显著性差异。在移植后第5 d、7 d,两组大鼠评分及血肿周围脑组织内凋亡细胞的数量开始下降,移植组下降幅度大于对照组,两组之间差异显著。移植后14 d,两组之间无显著性差异。结论骨髓间充质干细胞移植可明显促进大鼠脑出血后神经功能的恢复,其机制可能与下调血肿周围神经细胞凋亡有关。     

人羊膜上皮细胞侧脑室移植治疗脑出血大鼠实验研究

目的 探讨人羊膜上皮细胞(hAECs)侧脑室移植对脑出血(ICH)大鼠脑水肿与神经功能恢复的影响.方法 分离培养hAECs,用Hoechst33258和增强绿色荧光蛋白(EGFP)标记hAECs,将其移植入脑出血大鼠侧脑室中,测试大鼠28 d内的运动功能变化与脑水肿的动态变化,并行免疫组织化学观察.结果 移植hAECs沿大鼠侧脑室壁生长,细胞存活4 w以上.巢蛋白(nestin)与波形蛋白(vim)免疫组化检测呈阳性表达,病灶周围小胶质细胞OX-42染色阳性细胞减少.移植组ICH大鼠脑含水量减少,神经功能明显改善.结论 hAECs移植到ICH大鼠侧脑室可存活,表达神经元特异性抗原,并减轻ICH大鼠脑水肿,改善运动功能.     

HNG抗脑出血炎性损伤的神经保护作用

目的 研究[Gly14]-humanin(HNG)对脑出血(ICH)模型大鼠的神经保护作用. 方法 将健康雄性SD大鼠30只采用随机数字表法分为HNG治疗组(10只)、模型组(10只)、假手术组(10只),立体定向注射自体血制作ICH模型,假手术组仪插入针,HNG治疗组大鼠在造模后侧脑室注射HNG,72 h后观察血肿周围胶质细胞和凋亡细胞的变化. 结果 术后72 h,HNG治疗组星形胶质细胞和小胶质细胞形态与模型组比较胞体小,突起短、细;HNG治疗组血肿周围胶质纤维酸性蛋白GFAP、OX42阳性细胞数以及凋亡细胞数量005.3±10.19,173.2±21.72.26.1±5.97)较模型组(141.8±9.77,212.2±15.38,48.6±10.94)明显减少,但仍高于假手术组,差异有统计学意义(P均<0.05). 结论 HNG在大鼠ICH后血肿周围脑组织中具有抗炎症性神经保护作用.     

Transplantation of primed human fetal neural stem cells improves cognitive function in rats after traumatic brain injury

Traumatic brain injury (TBI) often produces cognitive impairments by primary or secondary neuronal loss. Stem cells are a potential tool to treat TBI. However, most previous studies using rodent stem or progenitor cells failed to correlate cell grafting and cognitive improvement. Furthermore, the efficacy of fetal human neural stem cells (hNSCs) for ameliorating TBI cognitive dysfunction is undetermined. This study therefore characterized phenotypic differentiation, neurotrophic factor expression and release and functional outcome of grafting hNSCs into TBI rat brains. Adult Sprague-Dawley rats underwent a moderate parasagittal fluid percussion TBI followed by ipsilateral hippocampal transplantation of hNSCs or vehicle 1 day post-injury. Prior to grafting, hNSCs were treated in vitro for 7 days with our previously developed priming procedure. Significant spatial learning and memory improvements were detected by the Morris water maze (MWM) test in rats 10 days after receiving hNSC grafts. Morphological analyses revealed that hNSCs survived and differentiated mainly into neurons in the injured hippocampus at 2 weeks after grafting. Furthermore, hNSCs expressed and released glial-cell-line-derived neurotrophic factor (GDNF) in vitro and when grafted in vivo, as detected by RT-PCR, immunostaining, microdialysis and ELISA. This is the first direct demonstration of the release of a neurotrophic factor in conjunction with stem cell grafting. In conclusion, human fetal neural stem cell grafts improved cognitive function of rats with acute TBI. Grafted cells survived and differentiated into neurons and expressed and released GNDF in vivo, which may help protect host cells from secondary damage and aid host regeneration.     

Primate embryonic stem cell-derived neuronal progenitors transplanted into ischemic brain.

Transplantation of stem cells has the possibility of restoring neural functions after stroke damage. Therefore, we transplanted neuronal progenitors generated from monkey embryonic stem (ES) cells into the ischemic mouse brain to test this possibility. Monkey ES cells were caused to differentiate into neuronal progenitors by the stromal cell-derived inducing activity method. Focal cerebral ischemia was induced by occluding the middle cerebral artery by the intraluminal filament technique. The donor cells were transplanted into the ischemic lateral striatum at 24 h after the start of reperfusion. The cells transplanted into the ischemic brain became located widely around the ischemic area, and, moreover, the transplanted cells differentiated into various types of neurons and glial cells. Furthermore, at 28 days after the transplantation, over 10 times more cells in the graft were labeled with Fluorogold (FG) by stereotactic focal injection of FG into the anterior thalamus and substantia nigra on the grafted side when compared with the number at 14 days. From these results we confirmed the survival and differentiation of, as well as network formation by, monkey ES-cell-derived neuronal progenitors transplanted into the ischemic mouse brain.     

Transplantation of neural stem cells that overexpress SOD1 enhances amelioration of intracerebral hemorrhage in mice

Previous studies have shown that intraparenchymal transplantation of neural stem cells (NSCs) ameliorates neurologic deficits in animals with intracerebral hemorrhage (ICH). However, massive grafted cell death after transplantation, possibly caused by a hostile host brain environment, lessens the effectiveness of this approach. We focused on the effect of oxidative stress against grafted NSCs and hypothesized that conferring antioxidant properties to transplanted NSCs may overcome their death and enhance neuroprotection after ICH. Copper/zinc-superoxide dismutase (SOD1) is a specific antioxidant enzyme that counteracts superoxide anions. We investigated whether genetic manipulation to overexpress SOD1 enhances survival of grafted NSCs and accelerates amelioration of ICH. Neural stem cells that overexpress SOD1 were administered intracerebrally 3 days after ICH in a mouse model. Histologic and behavioral tests were examined after ICH. Copper/zinc-superoxide dismutase overexpression protected the grafted NSCs via a decrease in production of reactive oxygen species. This resulted in an increase in paracrine factors released by the NSCs, and an increase in surviving neurons in the striatum and a reduction in striatal atrophy. In addition, SOD1 overexpression showed progressive improvement in behavioral recovery. Our results suggest that enhanced antioxidative activity in NSCs improves efficacy of stem cell therapy for ICH.     

大鼠脑出血后内源性神经干细胞激活和增殖的实验研究

目的 观察大鼠脑出血模型内源性神经干细胞(NSCs)的激活、增殖情况及其对神经行为学表现的影响.方法 将72只SD大鼠按单双号分为脑出血组和假手术组.每组36只.脑出血组利用立体定向技术,将一定量的Ⅳ型胶原酶用微量进样器分别精确注入大鼠内囊诱导脑出血模型.假手术组注射等量体积的PBS.分别于术后1、7、14、21、28和35 d观察大鼠的神经功能表现.所有大鼠处死前1 d腹腔内注射5.溴脱氧尿嘧啶(BrdU),免疫组织化学方法动态检测大鼠脑内巢蛋白(nestin)和BrdU的表达.结果 假手术组大鼠脑内未见nestin和BrdU的表达.脑出血组血肿周围基底节和脑室下区可见nestin和BrdU的表达.脑出血后7 d后开始明显增加.14 d达高峰,21 d开始下降.28d恢复正常.脑出血后l～35d大鼠神经功能无明显恢复,与内源性NSCs的增殖程度无明显相关.结论 脑出血可导致内源性NSCs的激活和诱导其增殖:然而这种状态下NSCs的增殖能力和内源性NSCs对脑出血后神经功能缺损的修复均有限.     

骨髓间质干细胞联合脑源性神经营养因子用于大鼠脑出血的实验研究

目的观察骨髓间质干细胞(MSCs)联合脑源性神经营养因子(BDNF)治疗大鼠脑出血(ICH)的疗效。方法建立大鼠ICH模型,体外培养标记纯化的MSCs,经侧脑室植入脑部,同时局部注入BDNF。记录对照组、BDNF组、MSCs组和MSCs+BDNF组7d、14d、21d大鼠神经功能改善程度;免疫组化法检测MSCs脑内迁移及分化;电子显微镜观察神经凋亡细胞。结果 MSCs组大鼠运动功能有明显改善,MSCs+BDNF组对ICH损伤的修复作用最明显。MSCs+BDNF组各时间点MSCs阳性细胞数及NEUN、GFAP、CNP免疫阳性细胞数均高于MSCs组(P<0.01),且MSCs+BDNF组神经细胞凋亡程度最轻。结论 MSCs脑部移植可促进大鼠ICH损伤部位结构和功能修复,BDNF对其修复具有协同作用。     

TH基因修饰的神经干细胞移植治疗帕金森病的实验研究

目的 探讨TH基因修饰的神经干细胞脑内移植对帕金森病(PD)的治疗作用。方法 构建pN：ATH逆转录病毒载体质粒，用PA317细胞包装，G418筛选阳性克隆，病毒上清感染神经干细胞，将表达TH的神经干细胞植入：PD大鼠纹状体内，测定：PD大鼠旋转行为改善，DA和DOPAC含量变化，以及TH在纹状体的表达。结果 TH基因修饰的神经干细胞移植8周时能显著降低PD大鼠旋转行为，增加纹状体DA和DOPAC含量，TH在纹状体内的表达增加，疗效好于单纯神经干细胞移植组。结论 TH基因修饰的神经干细胞移植对PD大鼠有明显的治疗作用，可望为PD治疗提供新的途径。     

脑出血大鼠脑内神经干细胞移植的研究

目的分离并克隆新生大鼠神经干细胞,研究其移植入脑出血大鼠脑内的生物学特征,了解神经干细胞移植治疗脑出血的可行性.方法用尾状核注射Ⅶ型胶原酶制作脑出血模型,从Wistar新生大鼠脑室下区分离并克隆神经干细胞,经Brdu(5-溴脱氧尿嘧啶)掺入标记后移植入脑出血同侧的侧脑室或脑出血对侧的尾状核中.经免疫组织化学鉴定了解移植细胞在大鼠脑内的生存、迁移及分化情况.结果将稳定培养的神经干细胞移植入脑出血大鼠脑内,发现移植后4 d移植细胞仍存在.侧脑室移植组中移植细胞多在侧脑室周边区存在,尾状核移植组可见移植细胞开始向对侧迁移.免疫荧光双标证实细胞大多分化成神经元,少部分分化成胶质细胞.结论神经干细胞移植入脑出血大鼠脑内后能够存活,并能有效地穿过室管膜和向脑出血部位迁移.移植细胞在脑内大部分分化成神经元,少部分分化成胶质细胞.     

Therapeutic effect of human umbilical cord mesenchymal stem cells on neonatal rat hypoxic–ischemic encephalopathy

The therapeutic potential of umbilical cord blood mesenchymal stem cells has been studied in several diseases. However, the possibility that human umbilical cord Wharton's jelly‐derived mesenchymal stem cells (hUCMSCs) can be used to treat neonatal hypoxic–ischemic encephalopathy (HIE) has not yet been investigated. This study focuses on the potential therapeutic effect of hUCMSC transplantation in a rat model of HIE. Dermal fibroblasts served as cell controls. HIE was induced in neonatal rats aged 7 days. hUCMSCs labeled with Dil were then transplanted into the models 24 hr or 72 hr post‐HIE through the peritoneal cavity or the jugular vein. Behavioral testing revealed that hUCMSC transplantation but not the dermal fibroblast improved significantly the locomotor function vs. vehicle controls. Animals receiving cell grafts 24 hr after surgery showed a more significant improvement than at 72 hr. More hUCMSCs homed to the ischemic frontal cortex following intravenous administration than after intraperitoneal injection. Differentiation of engrafted cells into neurons was observed in and around the infarct region. Gliosis in ischemic regions was significantly reduced after hUCMSC transplantation. Administration of ganglioside (GM1) enhanced the behavioral recovery on the base of hUCMSC treatment. These results demonstrate that intravenous transplantation of hUCMSCs at an early stage after HIE can improve the behavior of hypoxic–ischemic rats and decrease gliosis. Ganglioside treatment further enhanced the recovery of neurological function following hUCMSC transplantation. © 2013 Wiley Periodicals, Inc.     

Recruiting new neurons from the subventricular zone to the rat postnatal cortex: an organotypic slice culture model

The neurogenic subventricular zone (SVZ) of the lateral ventricle is a potential source for neuronal replacement in the postnatal or adult neocortex after injury. Here we present a novel model system to directly explore the cellular mechanisms of this process. In order to visualize directed migration from the SVZ towards the cortex, we transplanted green fluorescent protein-labeled progenitor/stem cells into the SVZ of newborn rats. At 2 days after transplantation, we generated organotypic slice cultures and applied fluorescent time-lapse imaging to explore directly the migration and integration of donor cells into the host tissue for up to 2 weeks. Our studies revealed that subventricular grafts provide a significant number of immature neurons to neocortical regions. In the cortex, immature neurons first migrate radially towards the pial surface and then differentiate into GABAergic interneurons. We conclude that our model system presents a novel and effective experimental paradigm to evaluate the recruitment of SVZ-derived neurons into the postnatal cortex, a phenomenon that may represent a potential route for cortical repair.     

Mesencephalic neural stem (progenitor) cells develop to dopaminergic neurons more strongly in dopamine-depleted striatum than in intact striatum

Epidermal growth factor (EGF)/fibroblast growth factor (FGF)-responsive stem (progenitor) cells from embryonic brain have self-renewing and multipotent properties and thus are good candidates for donor cells in neural transplantation. However, the survival and differentiation to mature neurons after grafting of stem cells into adult brain are rather poor. We hypothesize that the differentiation of stem cells to mature neurons, such as dopaminergic (DAergic) neurons, is dependent on environmental cues that control the ontogenic development. We compared the survival and differentiation between mesencephalic (MS) and cortical (CTx) stem (progenitor) cells, following grafting into bilateral striata of hemiparkinsonian model rats. MS and CTx stem cells were prepared from E12 rats and proliferated in serum-free medium with EGF or basic FGF for 2 weeks. One day after being primed to differentiate, the cell suspensions of both origins were grafted into the bilateral striata of adult rats that had unilateral 6-OHDA lesions in the substantia nigra. MS cells differentiated to tyrosine hydroxylase (TH)-positive neurons more strongly in DA-depleted striatum than in intact striatum, and methamphetamine-induced rotation was ameliorated in half of the grafted animals. Rosette-like cell aggregation and dysfunction of the blood-brain barrier (BBB) were less in and around the grafts in DA-depleted striatum, suggesting less proliferation and more differentiation of MS stem cells in DA-depleted striatum. Neither TH-positive neurons nor behavioral amelioration were detected following CTx stem (progenitor) cell transplantation in the striata. Data suggest that the DA-depleted striatum offers a suitable environment for MS stem (progenitor) cells to differentiate into mature DAergic neurons.     

Transplantation of neural cells derived from retinoic acid-treated cynomolgus monkey embryonic stem cells successfully improved motor function of hemiplegic mice with experimental brain injury

We induced neural cells by treating cynomolgus monkey embryonic stem (ES) cells with retinoic acid. The treated cells mainly expressed betaIIItubulin. They further differentiated into neurons expressing neurofilament middle chain (NFM) in elongated axons. Half of the cells differentiated into Islet1+ motoneurons in vitro. The monkey ES-derived neural cells were transplanted to hemiplegic mice with experimental brain injury mimicking stroke. The neural cells that had grafted into periventricular area of the mice distributed extensively over the injured cortex. Some of the transplanted cells expressed the neural stem/progenitor marker nestin 2 days after transplantation. The cells expressed markers characteristic of mature motoneurons 28 days after transplantation. Mice with the neural cell graft gradually recovered motor function, whereas control animals remained hemiplegic. This is the first demonstration that neural cells derived from nonhuman primate ES cells have the ability to restore motor function in an animal model of brain injury.