Zigova Tanja, Song Shijie, Willing Alison E, Hudson Jennifer E, Newman Mary B, Saporta Samuel, Sanchez-Ramos Juan, Sanberg Paul R
Center for Aging and Brain Repair, Department of Neurosurgery, University of South Florida College of Medicine, Tampa 33612, USA.
Cell Transplant. 2002;11(3):265-74.
Recently, our laboratory began to characterize the mononuclear cells from human umbilical cord blood (HUCB) both in vitro and in vivo. These cryopreserved human cells are available in unlimited quantities and it is believed that they may represent a source of cells with possible therapeutic and practical value. Our previous molecular and immunocytochemical studies on cultured HUCB cells revealed their ability to respond to nerve growth factor (NGF) by increased expression of neural markers typical for nervous system-derived stem cells. In addition, the DNA microarray detected downregulation of several genes associated with development of blood cell lines. To further explore the survival and phenotypic properties of HUCB cells we transplanted them into the developing rat brain, which is known to provide a conducive environment for development of neural phenotypes. Prior to transplantation, HUCB cells were either cultured with DMEM and fetal bovine serum or were exposed to retinoic acid (RA) and nerve growth factor (NGF). Neonatal pups (1 day old) received unilateral injection of cell suspension into the anterior part of subventricular zone. One month after transplantation animals were perfused, their brains cryosectioned, and immunocytochemistry was performed for identification of neural phenotypes. Our results clearly demonstrated that approximately 20% of transplanted HUCB survived (without immunosuppression) within the neonatal brain. Additionally, double-labeling with cell-type-specific markers revealed that some HUCB-derived cells (recognized by anti-human nuclei labeling) were immunopositive for glial fibrillary acidic protein (GFAP) and few donor cells expressed the neuronal marker TuJ1 (class III beta-tubulin). These findings suggest that at least some of the transplanted HUCB cells differentiated into cells with distinct glial or neuronal phenotypes after being exposed to instructive signals from the developing brain.
最近，我们的实验室开始在体外和体内对人脐带血（HUCB）中的单核细胞进行特性分析。这些冷冻保存的人类细胞数量不限，据信它们可能代表了具有潜在治疗和实用价值的细胞来源。我们之前对培养的HUCB细胞进行的分子和免疫细胞化学研究表明，它们能够通过增加表达神经系统来源干细胞典型的神经标志物来响应神经生长因子（NGF）。此外，DNA微阵列检测到与血细胞系发育相关的几个基因表达下调。为了进一步探索HUCB细胞的存活和表型特性，我们将它们移植到发育中的大鼠脑中，已知该脑为神经表型的发育提供了有利环境。在移植前，HUCB细胞要么用DMEM和胎牛血清培养，要么暴露于视黄酸（RA）和神经生长因子（NGF）。新生幼鼠（1日龄）接受单侧脑室下区前部细胞悬液注射。移植后一个月，对动物进行灌注，将其大脑冷冻切片，并进行免疫细胞化学鉴定神经表型。我们的结果清楚地表明，大约20%的移植HUCB细胞（无需免疫抑制）在新生脑内存活。此外，用细胞类型特异性标志物进行双重标记显示，一些HUCB来源的细胞（通过抗人核标记识别）对胶质纤维酸性蛋白（GFAP）呈免疫阳性，少数供体细胞表达神经元标志物TuJ1（III类β-微管蛋白）。这些发现表明，至少一些移植的HUCB细胞在受到发育中大脑的诱导信号后分化为具有不同胶质或神经元表型的细胞。
