Insulin releasing cells derived from embryonic stem cells and new semipermeable membranes for bioartificial pancreas.

ES细胞来源的多巴胺能神经元：收集PA6细胞洗涤后产生的神经诱导因子。包裹在半透膜中的ES细胞在含有NIF的培养液中可以有效地分化为多巴胺能神经元。培养16d后，ES细胞中可见明显的β-微管蛋白III型阳性细胞和酪氨酸羟化酶阳性细胞，56 mM KCl15 mM作用于ES细胞可见多巴胺释放。ES细胞在半透膜中的分化是实现帕金森病细胞治疗的关键步骤之一。ES细胞来源的胰岛素释放细胞：用四步法在有无胎牛血清的培养液中获得胰岛素释放的ES细胞后代。取细胞质分别用抗胰岛素抗体和抗C肽抗体进行染色。这些细胞可以传代9次。结果表明，从ES细胞中可以获得足够数量的胰岛素释放细胞用于糖尿病患者的细胞移植治疗。免疫隔离膜：一种氨基封端的聚乙二醇偶联磷脂(PEG脂，MW：5000)，当它们加入细胞悬浮液中时，会自发地在细胞上形成一层薄层。通过聚乙二醇链末端氨基与海藻酸钠和多L赖氨酸形成的多离子络合物，可以在聚乙二醇脂素层上形成逐层膜。这种方法可以在不增加细胞体积的情况下将细胞微囊化。

Dopaminergic Neurons Derived from ES Cells : Neural inducing factors (NIFs) produced by washing PA6 cells were collected. ES cells enclosed in semipermeable membranes could be efficiently differentiated to dopaminergic neurons using medium containing NIFs. β-tubulin type III positive cells and tyrosine hydroxylase positive cells were clearly observed in ES cell progenies after 16 days culture, and dopamine release were seen when cells were exposed to 56 mM KCl for 15 mm through deporization of neurons. Differentiation of ES cells in semipermeable membranes is one of crucially important procedures when cell therapy of Parkinson's disease will be realized.Insulin Releasing Cells Derived from ES Cells : Insulin releasing ES cell progeny was derived in culture media with/without fetal calf serum by the 4 step procedure. Cells of which cytoplasm was stained by the anti-insulin antibody and by anti-C-peptide antibodies were obtained. Those cells can be subculture 9 times. The results suggest that a sufficient number of insulin releasing cells could be obtained from ES cells for the cell transplantation therapy of diabetic patients.Membrane for Immunoisolation : An amino groups-terminated poly (ethylene glycol)-conjugated phospholipids (PEG-lipids, Mw : 5000) spontaneously formed a thin layer on cells, when they were added to cells suspension. The layer-by-layer membrane could be further formed on the PEG-lipid layer through the polyion complex formation between amino groups at the end of PEG chains, sodium alginate and poly-L-lysine. Cells could be microencapsulated by this method without volume increase.