Histological Analysis of Microencapsulated Dopamine-Secreting Cells in Agarose/Poly(styrene sulfonic acid) Mixed Gel Xenotransplanted into the Brain
Histological Analysis of Microencapsulated Dopamine-Secreting Cells in Agarose/Poly(styrene sulfonic acid) Mixed Gel Xenotransplanted into the Brain
复制标题
琼脂糖/聚苯乙烯磺酸混合凝胶中微囊化多巴胺分泌细胞异种移植到大脑中的组织学分析
作者：
Y. Miyoshi;I. Date;T. Ohmoto;H. Iwata
PC12细胞被封装在琼脂糖/聚苯乙烯磺酸（琼脂糖/PSSa）混合凝胶中，并异种移植到豚鼠的大脑中。评估琼脂糖/PSSa微胶囊的免疫保护能力和生物相容性。移植后至少 5 周，在所有豚鼠中观察到微胶囊内酪氨酸羟化酶阳性的 PC12 细胞。 PC12细胞尺寸相对均匀较小，偶尔形成细胞团；然而，细胞坏死并不明显。宿主对琼脂糖/PSSa 微胶囊的反应最小。微胶囊周围的胶质原纤维酸性蛋白阳性星形胶质细胞密度程度与注射轨迹周围相似。通过尼氏染色评估，脑/微胶囊界面周围的坏死并不明显。在胶囊附近观察到外观正常的神经元。高效液相色谱和电化学检测显示 PC12 细胞封装的微胶囊在体外有基础和钾诱发的多巴胺释放。我们得出的结论是，使用琼脂糖/PSSa混合凝胶进行封装不仅可以将封装的细胞与宿主免疫系统隔离，还可以允许营养物质和神经递质的扩散交换。使用琼脂糖/PSSa混合凝胶进行封装可以扩大神经移植供体组织的范围。
PC12 cells were encapsulated within agarose/poly-(styrene sulfonic acid) (agarose/PSSa) mixed gel and xenotransplanted into the brains of guinea pigs. The immunoprotection capability and biocompatibility of the agarose/PSSa microcapsules were evaluated. Tyrosine hydroxylase-positive PC12 cells within the microcapsules were observed in all guinea pigs at least 5 weeks after transplantation. PC12 cells had a relatively uniform small size and occasionally formed cell clusters; however, cell necrosis was not apparent. The host reaction to agarose/PSSa microcapsules was minimal. The degree of glial fibrillary acidic protein-positive astrocyte density around the microcapsules was similar to that around the injection tracks. Necrosis around the brain/microcapsule interface was not apparent as assessed by Nissl staining. Normal-appearing neurons were observed in close vicinity to the capsule. High-performance liquid chromatography with electrochemical detection showed basal and potassium-evoked release of dopamine from the PC12 cell-enclosed microcapsules in vitro. We conclude that encapsulation using agarose/PSSa mixed gel can not only isolate the enclosed cells from the host immune system but can also allow diffusional exchange of nutrients and neurotransmitters. Encapsulation using agarose/PSSa mixed gel may expand the range of donor tissues for neural transplantation.