Lundberg C, Martínez-Serrano A, Cattaneo E, McKay R D, Björklund A
Wallenberg Neuroscience Center, Department of Physiology and Neuroscience, University of Lund, Sweden.
Exp Neurol. 1997 Jun;145(2 Pt 1):342-60. doi: 10.1006/exnr.1997.6503.
The in vivo properties of four different neural stem cell lines, generated from embryonic striatum or hippocampus by immortalization with the temperature-sensitive (s) A58/U19 allele of the SV40 Large T-antigen, have been studied with respect to their ability to survive, differentiate, and integrate after transplantation to the adult rat striatum. The cells were labeled with [3H]thymidine prior to grafting, and combined autoradiography and immunohistochemistry was used to characterize their phenotypic differentiation within the adult brain environment. The results show that all four types of cells survived well, up to at least 1.5-6 months postgrafting, without any signs of tissue perturbation or tumor formation. The cells underwent, on average, 2-3 cell divisions during the first 5 days after implantation and exhibited extensive migration over a distance of 1-1.5 mm from the injection site to become morphologically integrated with the surrounding host striatum. The cell number and tissue distribution attained by 2 weeks remained stable for up to 6 months postgrafting with the exception of one cell line, which showed a 40% loss of cells between 2 and 6 weeks. Twice the number of [3H]thymidine-labeled cells were recovered when the cells were grafted into a 1-week-old excitotoxic striatal lesion, probably due to an increased proliferation of the cells in response to the neuron-depleting depleting lesion. The immortalized cells behaved as multipotent neural progenitors. The vast majority of the cells developed a glial-like morphology, 6-14% being clearly GFAP-positive; however, a small but consistent proportion of them (1-3%) expressed MAP-2 and exhibited neuron-like morphology. In mature transplants about 75-80% of the grafted cells were located in the striatal grey matter, and 10-15% in white matter, some of which are proposed to have differentiated into oligodendrocytes. Remaining 5-10% occurred around small blood vessels (resembling pericytes) and in the subventricular zone underneath the ependyma of the lateral ventricle. It is concluded that the ts cell lines are highly suitable for intracerebral transplantation and that they allow the creation of a regionally confined cellular chimeras where the graft-derived glial cells become stably integrated with the resident glial cell matrix.
利用温度敏感型SV40大T抗原的A58/U19等位基因永生化技术，从胚胎纹状体或海马体中生成了四种不同的神经干细胞系，并对其在移植到成年大鼠纹状体后的存活、分化和整合能力进行了体内研究。移植前，细胞用[3H]胸腺嘧啶核苷进行标记，并结合放射自显影和免疫组织化学来表征它们在成年脑环境中的表型分化。结果表明，所有四种类型的细胞存活良好，移植后至少存活1.5 - 6个月，没有任何组织扰动或肿瘤形成的迹象。植入后的前5天，细胞平均经历2 - 3次细胞分裂，并从注射部位迁移1 - 1.5毫米的距离，表现出广泛的迁移，从而在形态上与周围的宿主纹状体整合。除了一个细胞系在2至6周内细胞数量减少40%外，移植后2周时达到的细胞数量和组织分布在长达6个月的时间内保持稳定。当将细胞移植到1周龄的兴奋性毒性纹状体损伤中时，回收的[3H]胸腺嘧啶核苷标记细胞数量增加了一倍，这可能是由于细胞对神经元耗竭性损伤的增殖反应增加所致。永生化细胞表现为多能神经祖细胞。绝大多数细胞呈现出胶质样形态，6 - 14%明显为GFAP阳性；然而，其中一小部分但比例一致的细胞（1 - 3%）表达MAP - 2并呈现神经元样形态。在成熟移植中，约75 - 80%的移植细胞位于纹状体灰质中，10 - 15%位于白质中，其中一些被认为已分化为少突胶质细胞。其余5 - 10%出现在小血管周围（类似于周细胞）和侧脑室室管膜下方的室下区。结论是，ts细胞系非常适合脑内移植，并且它们允许创建局部受限的细胞嵌合体，其中移植来源的胶质细胞与驻留的胶质细胞基质稳定整合。
