Chemosensitivity test using immunoprotected culture system in vivo.

低分子量物质如葡萄糖可以通过由聚赖氨酸和海藻酸盐组成的膜，但高分子量物质如免疫球蛋白不能通过这种膜。因此，活细胞的微囊化可以保护异种移植细胞免受排斥。本研究的目的是建立一种新的微囊化人癌细胞移植到小鼠体内的化疗药物敏感性检测系统。1.细胞培养微囊的制备采用Lin报道的方法，以子宫内膜腺癌细胞系石川细胞为囊化细胞。将细胞以1 × 10^6/ml的浓度悬浮在海藻酸钠中。用多聚赖氨酸包被细胞悬液后，再用海藻酸钠和氯化钙洗涤凝胶。用柠檬酸钠进一步洗涤以液化胶囊内的凝胶。具有夹在2层藻酸盐之间的聚赖氨酸膜的胶囊的适当尺寸为直径为0.5mm以用于操作。2.微囊的体外培养将微囊悬浮于培养基中，密闭培养，倒置显微镜下观察发现，早期的孤立癌细胞，在微胶囊中迅速生长发泡聚集体。通过SDI分析评估的包封细胞的生长曲线显示细胞的指数生长。

Low molecular weight substances such as glucose can pass through the membrane composed of polylysine and alginate, but the high molecular weight substances such as immunoglobulin can not pass through this membrane. Therefore, microencapsulation of living cells can protect heterotransplanted cells from rejection. This research aims to establish a new chemosensitivity test system using microencapsulated human cancer cells transplanted into mouse in vivo.1.Cell encapsulationThe microcapsules were produced according to the procedure originally reported by Lin, using the Ishikawa cells (an established endometrial adenocarcinoma cell line) for encapsulated cells. Cells were suspended in sodium alginate at a concentration of 1x10^6/ml. This cell suspension formed gelled spherical microdroplets by atomizing into CaCl_2 After coated with polylysine, the gels were washed with sodium alginate and CaCl_2 again. Further washing was employed with sodium citrate to liquify the gel inside the capsules. The adequate size of the capsules with a membrane of polylysine sandwiched between 2 layrs of alginate were 0.5 mm in diameter for manipulation.After several trials and errors, the microcapsules could be produced smoothly.2.Cultivation of the microcapsules in vitroThe capsules were suspended in the culture media and cultured under the closed condition.The phasecontrast microscopic findings revealed that the solitary cancer cells in its early stage grow rapidly foaming aggregates in the microcapsules. The growth curves of the encapsulated cells assessed by SDI analysis showed exponential growth of the cells.