人胚神经干细胞及人脐血干细胞移植治疗大鼠脑缺血的实验研究

目的 研究人胚神经干细胞（hNSCs）、人脐血干细胞（hUCBCs）移植治疗脑缺血大鼠的效果及其在缺血大鼠脑内的增殖、分化状况,并对两种干细胞移植的效果进行比较。方法 从自然流产的孕10～13周的人胚脑组织中分离、培养hNSCs;采集足月新生儿脐带血60～100ml,分离出其中的单个核细胞;移植前hNSCs、hUCBCs均经5–溴脱氧嘧啶尿苷（Brdu）标记48h。采用线栓法制作大鼠脑缺血模型,1d后经尾静脉移植未分化的hNSCs、hUCBCs入脑缺血大鼠体内,对移植后大鼠进行神经损害严重程度评分（NSS）,用免疫组化方法观察移植后hNSCs、hUCBCs的存活、迁移、分化状况。结果 从人胚脑中成功培养出hNSCs,培养条件下呈悬浮状态生长,形成神经球;hUCBCs在体外具有增殖能力。两移植组大鼠均自移植后21d起其NSS显著低于对照组（P<0.05）,两移植组移植前及移植后各时间点NSS分别比较未发现显著性差异（P>0.05）;移植后14、21、28、35d脑组织切片中均可见Brdu染色阳性细胞,缺血侧明显多于对侧（P<0.05）,移植后21、28、35d明显多于移植后14d（P<0.05）;hNSCs组Brdu染色阳性细胞数多于hUCBCs组（P<0.05）;移植组各时间点脑组织切片中均可见nestin染色阳性细胞;在Brdu阳性细胞群中,hNSCs组73.8%为胶质纤维酸性蛋白（GFAP）染色阳性细胞,16.7%为2,3–环核苷酸磷酸二脂酶（CNPase）染色阳性 细胞,9.5%为神经元特异性烯醇化酶（NSE）染色阳性细胞;hUCBCs移植组74.5%为GFAP染色阳性细胞,15.4%为CNPase染色阳性细胞,10.1%为NSE染色阳性细胞;两组比较差异无显著性（P>0.05）。结论 hNSCs、hUCBCs均具有多分化潜能,受缺血部位微环境信号的影响分化成3种主要类型的神经细胞;静脉移植hNSCs、hUCBCs能有效改善脑梗死动物的神经功能;除了hNSCs外,hUCBCs移植也是治疗缺血性脑血管病的一种可能手段。     

人胚神经干细胞移植治疗大鼠脑缺血的实验研究

目的　研究人胚神经干细胞(hNSCs)移植治疗脑缺血大鼠的效果及其在缺血大鼠脑内的状况。方法　从自然流产的孕10~13周的人胚脑组织中分离、培养神经干细胞。采用线栓法制作大鼠脑缺血模型,1d后经尾静脉移植未分化的hNSCs入脑缺血大鼠体内,对移植后大鼠进行神经损害严重程度评分(NSS),用免疫组化方法观察移植后hNSCs的存活、迁徙、分化状况。结果　从人胎脑中成功培养出hNSCs,培养条件下呈悬浮状态生长,形成神经球,绝大多数的细胞表达神经干细胞的标记物神经巢蛋白(nestin)。hNSCs移植组大鼠自移植后3周末起其NSS显著低于对照组(P<0 .05);移植后2、3、4、5周脑组织切片中均可见5 溴脱氧嘧啶尿苷(Brdu)染色阳性细胞,缺血侧明显多于对侧(P<0 .05),移植后3、4、5周末明显多于移植后2周(均P<0 .05);移植组各时间点脑组织切片中均可见nestin染色阳性细胞;在Brdu阳性细胞群中, 73 8%为胶质纤维酸性蛋白(GFAP)染色阳性的星形胶质细胞, 16 7%为2, 3 环核苷酸磷酸二脂酶(CNPase)染色阳性的少突胶质细胞, 9 5%为神经元特异性烯醇化酶(NSE)染色阳性的神经元。结论　经静脉移植hNSCs能有效改善脑梗死动物的神经功能,hNSCs体内体外均具有多向分化潜能,受缺血部位微环境信号的影响分化成3种主要类型的神经细胞。     

人脐血间充质干细胞静脉移植治疗大鼠局灶性脑缺血的实验研究

目的 探讨来源于人脐血的间充质干细胞经静脉移植治疗大鼠局灶性脑缺血的可行性及其机制.方法 将人脐血间充质干细胞在体外纯化、扩增并经BrdU标记后,经尾静脉移植到局灶性脑缺血大鼠体内,通过神经缺损评分观察移植后大鼠神经行为学改善情况,通过组织学方法观察移植到脑内的人脐血间充质干细胞表达脑源性神经营养因子和缺血灶周围微血管密度变化的情况.结果 人脐血间充质干细胞移植组大鼠的神经缺损评分显著低于对照组(P＜0.05);移植到脑内的人脐血间充质干细胞主要选择性分布于缺血灶周围区域并表达脑源性神经营养因子,移植组大鼠梗死灶周围的微血管密度显著高于对照组(P＜0.01).结论 经静脉注射移植人脐血间充质干细胞能明显促进局灶性脑缺血大鼠的神经行为功能恢复,促进缺血灶周边区微血管增生可能是人脐血间充质干细胞移植治疗局灶性脑缺血的机制之一.     

神经干细胞移植治疗大鼠脑缺血再灌注损伤的实验研究

目的探讨胎鼠皮质培养的神经干细胞移植治疗大鼠脑缺血再灌注损伤的可行性及疗效。方法取孕龄15d Sprague-Dawley(SD)胎鼠皮质细胞培养为神经干细胞;用线栓法制备大鼠脑缺血再灌注损伤模型;将24只健康SD大鼠分为假手术组、缺血对照组、缺血移植组,在移植后2周、4周依据Garcia的18分评分法对各组大鼠的神经功能进行评分;行脑灌注固定取材,免疫组化染色观察移植后神经干细胞的分化、迁移和整合情况。结果用胎鼠皮质培养的细胞nestin表达阳性;缺血移植组大鼠的神经功能评分明显高于缺血对照组(P<0.05);缺血移植组免疫组织化学染色能够检测到存活的BrdU阳性细胞,移植后4周时可见移植细胞向周围迁移、分化、参与血管形成,并可见梗死区边缘微血管明显增生;缺血移植组大鼠脑GFAP阳性细胞数较缺血对照组明显增多(P<0.05)。结论分离、培养胎鼠皮质细胞Nestin表达阳性,即是大鼠的神经干细胞;移植体外培养的神经干细胞能在脑缺血大鼠脑内存活、迁移、分化,并且对脑梗死大鼠的神经功能修复起到了积极作用。     

人脐血干细胞移植治疗实验性自身免疫性脑脊髓炎的研究

目的研究人脐血干细胞(HUCBCs)移植治疗实验性自身免疫性脑脊髓炎(EAE)的效果以及HUCBCs在EAE大鼠脑和脊髓的状况。方法从新生儿脐带血分离出单个核细胞,体外培养并予5-溴脱氧嘧啶尿苷(Brdu)标记48h。用豚鼠全脊髓匀浆免疫Wistar大鼠制备EAE模型。在免疫后14d将3&#215;106HUCBCs经尾静脉注射移植入EAE大鼠(移植组)体内,观察大鼠移植后不同时间的神经功能缺损评分、脑和脊髓脱髓鞘病灶数的变化;用免疫组化技术观察移植后的HUCBCs在EAE大鼠脑和脊髓内存活、迁徙、分化的状况,并与对照组比较。结果移植组大鼠移植后21d、28d的神经功能缺损评分显著低于对照组(均P&lt;0.05);移植后7d、14d、21d、28d脑和脊髓中均可见Brdu染色阳性细胞,移植后21d、28d明显多于移植后7d、14d(均P&lt;0.05);植入的HUCBCs在大鼠脑和脊髓内能向损伤区域迁徙并能分化为星形胶质细胞、少突胶质细胞和神经元。移植后14d、21d、28d脑和脊髓内脱髓鞘病灶数明显少于对照组(均P&lt;0.05)。结论HUCBCs移植能显著改善EAE大鼠的神经功能,并能在其脑和脊髓内存活、迁徙和分化,减少脱髓鞘...     

神经干细胞脑室内移植治疗大鼠脑缺血的实验研究

目的 探讨大鼠胚胎神经干细胞移植治疗局灶性脑缺血再灌注损伤的可行性。方法 取胎龄8～10d大鼠神经干细胞体外扩增．采用免疫组织化学方法检测神经干细胞及其分化后代的特异性标志巢蛋白（nestin）、胶质纤维酸性蛋白（GFAP）和神经元特异性烯醇化酶（NSE）的表达。以Brdu标记神经干细胞，分别于缺血后24h和4周移植至局灶性脑缺血大鼠模型的脑室内和梗死中心，比较不同移植部位和不同移植时间神经干细胞的存活、增殖和迁移情况。结果 移植后可见移植细胞存活至少8周以上．移植部位不同不影响细胞存活。脑室内移植细胞向脑缺血区域迁移．且以缺血后24h移植组较缺血后4周移植组迁移趋向性更强。结论 大鼠胚胎神经干细胞移植至局灶性脑缺血大鼠脑室内和梗死中心均可长期存活并广泛迁移．其迁移趋化能力与缺血后移植时间有关。     

神经干细胞移植治疗暂时性脑缺血的实验研究

目的:探讨神经干细胞移植治疗暂时性脑缺血的价值。方法:从孕14 d SD胎鼠海马组织中分离培养出神经干细胞,将BrdU标记的神经干细胞经立体定向移植到SD大鼠暂时性大脑中动脉梗死模型(tMCAO)纹状体缺血半暗区。移植后2～12周以神经损害严重程度评分(NSS)评价各组动物神经功能状况。移植后12周,免疫荧光染色观察移植后神经干细胞的分化、迁徙和整合情况。结果:分离和纯化出大鼠胚胎神经干细胞,呈nestin阳性,并具有自我更新及多向分化潜能。移植后的神经干细胞在宿主脑内迁徙,部分分化并表达神经元特异性标记Neurofilament。移植后8周起,神经干细胞移植组大鼠NSS评分明显低于其他2组。结论:神经干细胞移植能改善缺血后大鼠的神经功能状况。     

人脐血干细胞移植修复大鼠脊髓损伤的功能评价

背景：在脊髓损伤模型的研究中，BBB评分系统和斜板试验均与脊髓损伤程度高度相关。 目的：建立改进大鼠脊髓全横断模型，对比观察BBB评分和斜板试验在人脐血干细胞移植术后功能评价中的作用。 设计、时间及地点：观察对比实验，于2007-04/2008-07在广东省组织构建与检测重点实验室完成。 材料：脐血来自健康足月产妇。实验动物为SPF级健康成年雌性SD大鼠50只，随机分为假手术对照组（n＝10）、磷酸盐注射组（n=20）、脐血干细胞移植组（n=20）。 方法：分离和体外培养人脐血干细胞。在显微镜下纵行剖开SD大鼠硬脊膜囊后，于硬脊膜内、蛛网膜外将超薄刀片刀尖直抵椎体骨质，将蛛网膜、脊髓、两侧壁和腹侧的硬脊膜作为一个整体完全划断，制作大鼠脊髓全横断模型，假手术对照组仅打开椎板，脐血干细胞移植组大鼠于脊髓两断端分别显微注射人脐血干细胞悬液6×109 ~7×109L-1，磷酸盐注射组注射等量磷酸盐缓冲液。 主要观察指标：术后12周内每2周分别应用BBB评分和斜板试验进行1次后肢运动功能评价。 结果：假手术对照组后肢运动功能于手术前后无显著变化。从术后第2周开始，磷酸盐注射组和脐血干细胞移植组逐渐恢复部分后肢运动功能，两组的BBB评分和斜板试验检测结果均表现出一致的增长趋势，呈线性正相关关系。从术后4周开始， BBB评分<13分的磷酸盐注射组和BBB评分≥13分的脐血干细胞移植组大鼠，在斜板试验中差异非常显著（P < 0.01）。到术后第12周时，磷酸盐注射组和脐血干细胞移植组斜板试验角度和恢复程度分别为34.25°和52.94％、53.85°和83.23％，并且脐血干细胞移植组高于磷酸盐注射组（P < 0.01），而同期磷酸盐注射组和脐血干细胞移植组对应的BBB评分和恢复程度仅分别为8.15和38.81％、13.90和66.19％，可见两组斜板试验角度恢复程度亦明显高于其自身对应的BBB评分结果。 结论：与BBB评分系统相比，斜板试验能更敏感地反映大鼠爪的功能恢复，但不能特异性地反映爪的精细运动。而作为主观评分体系的BBB评分系统，虽然特异性很高，但容易受主观因素的影响，敏感性较低。因此，联合应用BBB评分和斜板试验能更好地反映脊髓神经功能恢复情况。     

骨髓间充质干细胞移植治疗脑缺血大鼠的实验研究

目的评价骨髓间充质干细胞(BMSCs)移植对大鼠脑缺血后肌力、平衡力及空间学习能力的改善作用。方法栓塞大鼠大脑中动脉,制作40只脑缺血2 h再灌注动物模型,再灌注24 h后对移植组(20只)移植异体BMSCs。采用抓绳实验、平衡木行走实验及水迷宫实验,在缺血再灌注后1周、2周、4周和12周时对大鼠肌力、平衡力及空间学习能力进行检测,观察BMSCs移植后脑缺血大鼠神经功能恢复情况。结果脑缺血可导致大鼠肌力、平衡力及空间学习能力下降。缺血后随再灌注时间延长,移植组与对照组大鼠肌力、平衡力及空间学习能力均有一定程度的恢复,而移植组较对照组有明显改善。结论BMSCs移植可较显著地促进脑缺血大鼠肌力、平衡力及空间学习能力的改善。     

神经干细胞移植治疗大鼠脑缺血再灌注损伤实验研究

目的探讨大鼠胚胎神经干细胞移植治疗局灶性脑缺血再灌注损伤的可行性。方法孕龄8~10d的大鼠神经干细胞在体外扩增后,用免疫组织化学方法分别检测神经干细胞及其分化后代的特异性标志蛋白nestin、胶质纤维酸性蛋白(GFAP)和神经元特异性烯醇化酶(NSE)的表达。分别于缺血后不同时间窗将神经干细胞移植到局灶性脑缺血大鼠模型的缺血半暗带和梗塞中心,移植4w后比较不同移植部位神经干细胞存活、增殖和迁移的差异。结果从胎鼠中成功培养出悬浮生长的可表达nestin的神经球,其在含血清条件下可分化为表达GFAP的胶质细胞和表达NSE的神经元。神经干细胞移植4w后可见所有移植动物的细胞都存活,梗塞中心移植的细胞存活、增殖水平明显低于半暗带移植的细胞。结论大鼠胚胎神经干细胞移植到局灶性脑缺血再灌注损伤大鼠梗塞中心和半暗带均可长期存活,其增殖能力与移植部位密切相关。     

Stem cell transplantation for treatment of cerebral ischemia in rats Effects of human umbilical cord blood stem cells and human neural stem cells

BACKGROUND:Exogenous neural stem cell transplantation promotes neural regeneration. However, various types of stem cells transplantation outcomes remain controversial. OBJECTIVE:To explore distribution, proliferation and differentiation of human neural stem cells (hNSCs) and human umbilical cord blood stem cells (hUCBSCs) following transplantation in ischemic brain tissue of rats, and to compare therapeutic outcomes between hNSCs and hUCBSCs. DESIGN, TIME AND SETTING:Randomized controlled animal studies were performed at the Experimental Animal Center of Nanjing Medical University and Central Laboratory of Second Affiliated Hospital of Nanjing Medical University of China from September 2008 to April 2009. MATERIALS:hNSCs were harvested from brain tissue of 10-13 week old fetuses following spontaneous abortion, and hUCBSCs were collected from umbilical cord blood of full-term newborns at the Second Affiliated Hospital of Nanjing Medical University of China. hNSCs and hUCBSCs were labeled by 5-bromodeoxyuridine (BrdU) prior to transplantation. METHODS:Rat models of cerebral ischemia were established by the suture method. A total of 60 healthy male Sprague Dawley rats aged 7-9 weeks were randomly assigned to hNSC transplantation, hUCBSC transplantation and control groups. The rat models in the hNSC transplantation, hUCBSC transplantation and control groups were infused with hNSC suspension, hUCBSC suspension and saline via the caudal vein, respectively. MAIN OUTCOME MEASURES:The distribution, proliferation and differentiation of hNSCs and hUCBSCs in ischemic brain tissue were observed using immunohistochemical methods. Neurological function in rats was assessed using the neurological severity score. RESULTS:The number of BrdU-positive cells was significantly greater in the hNSC transplantation group compared with hUCBSC transplantation group at 14 days following transplantation (P < 0.05). The number of BrdU-positive cells reached a peak at 28 days following transplantation. Nestin-positive, glial fibrillary acidic protein-positive, cyclic nucleotide 3' phosphohydrolase-positive and neuron specific enolase-positive cells were visible following transplantation. No significant difference was determined in the constituent ratio of various cells between hNSC and hUCBSC transplantation groups (P > 0.05). The neurological severity score was significantly decreased in rats at 21 days following transplantation (P < 0.05). No significant difference was detected in neurological severity score between hNSC and hUCBSC transplantation groups at various time points (P > 0.05). CONCLUSION:The transplanted hNSCs and hUCBSCs can migrate into ischemic brain tissue, proliferate and differentiate into neuron-like, astrocyte-like and oligodendrocyte-like cells, and improve neurological function in rats with cerebral ischemia.     

人脐血细胞静脉移植对自发性高血压大鼠缺血再灌注脑损伤疗效及其机制探讨

目的探讨人脐血细胞(HUCBCs)静脉移植治疗自发性高血压(SHR)大鼠缺血再灌注脑损伤疗效及其相关机制。方法人脐血细胞体外分离、扩增并以4,6-2胺-2苯基吲哚(DAPi)标记。68只雄性SHR大鼠经线栓法建立大鼠大脑中动脉栓塞(MCAO)模型,并随机分为2组:治疗组和对照组。术后48h后经尾静脉治疗组注射1×106HUCBCs,对照组注射HUCBCs细胞培养基。于移植后3、14、28d,Bederson评分观察大鼠神经功能状况;图像分析法检测计算各组TTC染色脑梗死面积;荧光显微镜对治疗组脑组织DAPi染色阳性细胞计数;免疫组化法检测脑组织内脑源性神经营养因子(BDNF)染色阳性细胞数以及逆转录聚合链式反应(RT-PCR)检测移植后14、28d缺血侧脑组织BDNFmRNA表达水平。结果(1)移植后3d2组Bederson评分无显著差别,移植后14、28d治疗组显著低于对照组(P<0.05)。(2)移植后3d两组脑梗死面积无显著差别,移植后14、28d治疗组显著低于对照组(P<0.05)。(3)治疗组移植后3d梗死侧见少量DAPi阳性染色细胞,移植后14、28d梗死侧DAPi阳性染色细胞增加(P<0.05)...     

鼻腔内长期输送脐血单个核细胞对大鼠脑梗死体积及行为学的影响

背景：通过鼻腔输送细胞和具有生物活性的因子到大脑内是一种新的非侵入性输送方法,克服了其他给药方法受到血脑屏障限制和产生外周不良反应的缺点。目的：观察鼻腔内长期输送人脐血单个核细胞大鼠脑梗死梗死体积及行为学的变化。方法：直接切断Wistar大鼠一侧大脑中动脉制作脑梗死模型,将神经功能评分相当的模型大鼠,抽签随机分成对照组、单个核细胞组,随即单个核细胞组从鼻腔滴入培养的第3代人脐血单个核细胞,对照组滴入磷酸盐缓冲液,1次/d,共6周,每周进行1次行为学评价;最后1次行为学评价后行脑梗死体积量化检测。结果与结论：与对照组比较,治疗后3周单个核细胞组脑梗死大鼠改良的神经病学严重程度评分开始改善,之后进一步改善到5周(P < 0.05,P < 0.01);治疗后1~5周单个核细胞组Morris水迷宫实验平均潜伏期明显缩短(P < 0.05,P < 0.01),并且随着时间的延长,效果越明显。与行为学改善相一致,单个核细胞组脑梗死体积(9.15±4.36)%较对照组(30.56±4.65)%显著缩小(P < 0.01)。说明经鼻腔早期长期输注单个核细胞治疗大鼠脑梗死能改善其行为能力和缩小脑梗死体积,是治疗脑梗死的一种简便易行治疗方法。     

移植人脐带间充质干细胞修复大鼠脊髓损伤

背景：已知人脐带间充质干细胞对脊髓损伤存在着潜在的治疗价值,然而,当前对移植人脐带间充质干细胞治疗脊髓损伤及机制方面研究很少。 目的：观察人脐带间充质干细胞对脊髓损伤大鼠的治疗效果。 方法：40只Wistar大鼠建立脊髓损伤模型,38只造模成功后随机摸球法分为3组：空白对照组：只接受单纯损伤,不做任何移植;DMEM移植组：损伤后1周予以5 μL DMEM局部移植;细胞移植组：损伤后1周予以5 μL准备好的人脐带间充质干细胞局部移植(细胞数1×106)。移植后对实验动物通过BBB评分、体感诱发电位与运动诱发电位观察后肢功能恢复情况。分别于损伤后2,4,6,8,10周随机于细胞移植组抽取大鼠2只,免疫组织化学染色观察人脐带间充质干细胞存活、迁移、分化,通过胶质纤维酸性蛋白阳性细胞染色比较各组损伤局部胶质瘢痕形成面积。 结果与结论：BBB评分损伤后4周细胞移植组高于其他两组(P < 0.05),损伤后12周细胞移植组与其他两组相比SEP、MEP潜伏期缩短、波幅值增高(P < 0.05)。免疫组织化学染色示人脐带间充质干细胞可向神经元、星形胶质细胞和少突胶质细胞分化,分化的少突胶质细胞并包绕轴突形成髓鞘。细胞移植组损伤局部胶质瘢痕面积均小于其他两组(P < 0.05),空白对照组、DMEM移植组间差异无显著性(P > 0.05)。提示未经体外诱导的人脐带间充质干细胞可于损伤大鼠脊髓体内向神经元、星形胶质细胞、少突胶质细胞分化,减小胶质瘢痕,并促进脊髓损伤大鼠神经功能的恢复。     

脐血内皮祖细胞尾静脉与局部注射治疗糖尿病下肢缺血

背景：内皮祖细胞治疗糖尿病下肢缺血临床及动物实验多采用局部肌肉注射。 目的：比较脐血内皮祖细胞鼠尾静脉与局部注射治疗糖尿病下肢缺血效果的差异。 方法：取Wistar雄性大鼠分成5组：①糖尿病射线照射后结扎双后肢股动脉,尾静脉注射内皮祖细胞(DLV)。②糖尿病结扎双后肢股动脉左后肢局部肌肉注射PBS(DLC),右后肢局部肌肉注射内皮祖细胞(DLM)。③正常大鼠射线照射后结扎双后肢,尾静脉注射内皮祖细胞(NLV)。④糖尿病不结扎不注射内皮祖细胞(DC)。用绿色荧光示踪内皮祖细胞,苏木精-伊红染色检测肌纤维间毛细血管数,RT-PCR检测双后肢肌肉血管内皮生长因子mRNA水平。 结果与结论：DLV组与DLM组比较,右后肢腓肠肌溃疡及缺血好转明显,二者无明显区别;有明显荧光,差别不明显,Ⅷ因子免疫组织化学染色肌纤维间毛细血管数多,相互间无明显差别;腓肠肌血管内皮生长因子表达差异无显著性意义(P > 0.05)。提示脐血内皮祖细胞治疗糖尿病大鼠下肢缺血尾静脉注射与局部肌肉注射效果相当。     

Protective effects of human umbilical cord mesenchymal stem cell vein transplantation against spinal cord ischemia/reperfusion injury in rats

BACKGROUND: The majority of studies addressing spinal cord ischemia/reperfusion injury (SCIRI) have focused on drugs, proteins, cytokines, and various surgical techniques. A recent study reports that human umbilical cord mesenchymal stem cell (hUCMSC) transplantation achieves good therapeutic effects, but the mechanisms underlying nerve protection remain poorly understood.OBJECTIVE: To observe survival of transplanted hUCMSCs in SCIRI rat models and the influence on motor function in the hind limbs, to determine interleukin-8 expression and cellular apoptosis in spinal cord tissues, and to verify the hypothesis that hUCMSC transplantation exhibits protective effects on SCIRI.DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Laboratory of the Department of Orthopedics in the First Affiliated Hospital of Soochow University,China between January 2007 and December 2008.MATERIALS: hUCMSCs were harvested from umbilical cord blood of healthy pregnant women after parturition in the Obstetrical Department of the First Affiliated Hospital of Soochow University, China. Rabbit anti-human BrdU monoclonal antibody was provided by DAKO, USA. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) Kit and enzyme-linked immunosorbent assay (ELISA) Kit were purchased by Wuhan Boster, China. METHODS: A total of 72 healthy, Wistar, adult rats were randomly assigned to three groups: sham-surgery, model, and transplantation, with 24 rats in each group. SCIRI was induced in the model and transplantation groups via the abdominal aorta block method. The inf rarenal abdominal aorta was not blocked in the sham-surgery group. Prior to abdominal aorta occlusion, 0.2-0.3 mL bromodeoxyuridine (BrdU)-labeled hUCMSCs suspension (cell concentration 5 × 10~3/μL) was injected through the great saphenous vein of the hind limb, and an equal volume of physiological saline was administered to the model and sham-surgery groups.MAIN OUTCOME MEASURES: Pathological observation of rat spinal cord tissues was performed by hematoxylin-eosin staining at 6, 24, and 48 hours post-surgery. Immunohistochemistry was applied to determine hUCMSCs survival in the spinal cord. The amount of cellular apoptosis and interleukin-8 expression in spinal cord tissues was assayed utilizing the TUNEL and ELISA methods, respectively. Motor function in the hind limbs was evaluated according to Jacob's score. RESULTS: Numerous BrdU-positive cells were observed in spinal cord tissues from the transplantation group. The number of apoptotic cells and interleukin-8 levels significantly decreased in the transplantation group (P < 0.05), pathological injury was significantly ameliorated, and motor function scores significantly increased (P < 0.05) compared with the model group. CONCLUSION: Via vein transplantation, hUCMSCs were shown to reach and survive in the injury area. Results suggested that the transplanted hUCMSCs contributed to significantly improved pathological changes in the injured spinal cord, as well as motor function, following SCIRI. The protective mechanism correlated with inhibition of cellular apoptosis and reduced production of inflammatory mediators.     

Infusion of human umbilical cord blood cells protect against cerebral ischemia and damage during heatstroke in the rat

Intravenously delivered human umbilical cord blood cells (HUCBC) have been previously shown to improve both morphologic and functional recovery of heat-stroked rats. To extend these findings, we examined both the morphologic and functional alterations in the presence of HUCBC or human peripheral mononuclear cells (PBMC) 24 h before initiation of heatstroke. Anesthetized rats, 1 day before the initiation of heatstroke, were divided into three major groups and given the following: (a) serum-free lymphocyte medium (0.3 ml) intravenously; (b) PBMC (5 x 10(6) in 0.3 ml serum-free lymphocyte medium); or (c) HUCBC (5 x 10(6) in 0.3 ml serum-free lymphocyte medium). Another group of rats were exposed to room temperature (26 degrees C) and used as normothermic controls. In vehicle-treated heatstroke rats, their mean arterial pressure, cerebral blood flow, and brain PO(2) were all lower than in normothermic controls after the onset of heatstroke. However, their body temperatures and striatal levels of inducible nitric oxide synthase (iNOS)-dependent NO, ischemia and damage markers (e.g., glycerol, glutamate, and lactate/pyruvate ratio), and neuronal damage in the striatum were all greater. The heatstroke-induced arterial hypotension, cerebral ischemia and hypoxia, and increased levels of iNOS-dependent NO in the striatum were all significantly reduced by pretreatment with HUCBC, but not with PBMC. Moreover, HUCBC were localized by immunohistochemistry and PCR analysis in the injured brain structures and spleen. These findings indicate that HUCBC transplantation, in addition to having therapeutic values, can be a good choice for preventing heatstroke occurrence.     

Transplantation of mesenchymal stem cells from human umbilical cord versus human umbilical cord blood for peripheral nerve regeneration

BACKGROUND: Mesenchymal stem cells (MSCs) appear to be a good alternative to Schwann cells in the treatment of peripheral nerve injury. Fetal stem cells, like umbilical cord blood (UCB) and umbilical cord (UC) stem cells, have several advantages over adult stem cells.OBJECTIVE: To assess the effects of UC-derived MSCs (UCMSCs) and UCB-derived MSCs (UCBMSCs) in repair of sciatic nerve defects. DESIGN, TIME AND SETTING: A randomized controlled animal experiment was performed at the laboratory of Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital, from July to December 2009. MATERIALS: UCMSCs were provided by the Research Institute of Biotechnology, Dongguk University. UCBMSCs were provided by the Laboratory of Stem Cells and Tumor Biology, College of Veterinary Medicine, Seoul National University. Dulbecco's modified Eagle's medium (DMEM) was purchased from Gibco-BRL, USA. METHODS: Seven-week-old Sprague-Dawley rats were randomly and evenly divided into three groups: DMEM, UCBMSCs, and UCMSCs. A 10-mm defect in the left sciatic nerve was constructed in all rats. DMEM (15 μL) containing 1 × 106 UCBMSCs or UCMSCs was injected into the gap between nerve stumps, with the surrounding epineurium as a natural conduit. For the DMEM group, simple DMEM was injected. MAIN OUTCOME MEASURES: At 7 weeks after sciatic nerve dissection, dorsal root ganglia neurons were labeled by fluorogold retrograde labeling. At 8 weeks, electrophysiology and histomorphometry were performed. At 2, 4, 6, and 8 weeks after surgery, sciatic nerve function was evaluated using gait analysis.RESULTS: The UCBMSCs group and the UCMSCs group exhibited similar sciatic nerve function and electrophysiological indices, which were better than the DMEM group, as measured by gait analysis (P < 0.05). Fluorogold retrograde labeling of sciatic nerve revealed that the UCBMSCs group demonstrated a higher number of labeled neurons; however, the differences were not significant. Histomorphometric indices were similar in the UCBMSCs and UCMSCs groups, and total axon counts, particularly axon density (P < 0.05), were significantly greater in the UCBMSCs and UCMSCs groups than in the DMEM group. CONCLUSION: Transplanting either UCBMSCs or UCMSCs into axotomized sciatic nerves could accelerate and promote sciatic nerve regeneration over 8 weeks. Both treatments had similar effects on nerve regeneration.