Microencapsulated Multicell Tumor Spheroids

本研究的目的是建立评价放射或药物治疗恶性实体瘤疗效的体内检测体系。微囊的形成方法我们尝试建立了以海藻酸钠和聚L赖氨酸为原料制备球状微囊的体系。微胶囊的大小和形状、膜的通透性取决于海藻酸盐的聚合度和杀菌方法、空气喷嘴的形状、空气流量和聚L赖氨酸的相对分子质量。结果表明，聚合度为118、粘度为500CP的海藻酸钠在1%溶液中过滤杀菌，可得到直径约500微米的微囊。结论：1.使用相对分子质量为22,000的多聚L赖氨酸时，膜的稳定性和透过性均好于低分子量和高分子量的聚赖氨酸。微囊包裹的人癌细胞在体外原位快速增殖，形成多细胞肿瘤球体。当这些胶囊被移植到腹膜内或皮下时，大量的血细胞附着在微囊的表面，很难从小鼠体内回收这些微囊，时间间隔较长。细胞存活率：每孔细胞数与每孔平均光密度之间呈线性关系。曲线的斜率取决于细胞的存活率。利用这种关系。‘获得了GBA-7和TE-2人癌细胞对X射线剂量的存活曲线。结果表明，GBA-7细胞比TE-2细胞对X射线具有更强的耐受性，这与集落形成实验得到的结果相当。

The purpose of this investitgation is to establish the assay system in vivo for evaluating the therapeutic effect of radiation or drugs on malignant solid tumors.1. Method of microcapsules FormationWe tried to set up the system for making microcapsules of perfect spherical shape using sodium alginate and poly-L-lysine. The size and shape of the microcapsules, membrane permeability depended on the degree of polymerization and sterilization method of the alginate, shape of air jet nozzle, flow rate of air and molecular weight of poly-L-lysine. It was concluded for obtaining microcapsules of about 500 mum diameter to use the sodium alginate of polymerization degree 118 and viscosity of 500 CP at 1% solution, the sterilization by filtration. The stability and permeability of the membrance was better to use poly-L-lysine of MW 22, 000 than that of lower or higher molecular weight.2. Proliferation of Cancer Cells and In Vivo Transplantation.Human cancer cells encapsulated in the microcapsules proliferated rapidly in situ to forny a multicell tumor spheroid in vitro. When these capsules were transplanted either intraperitoneally or subcutaneously, numerous blood cells were attached to the surface of the microcapsules and it became difficult to recover these microcapsules from mice with a longer time interval.3. Cell Survival Assay.A linear proportional relationship was obtained between the number of cells plated per well and the mean optical density per well. The slope of the curve depended upon the surviving fraction of cells. Using this relationship. ' the survival curves of GBA-7 and TE-2 human cancer cells against the dose of X-ray were obtained. The result indicates that GBA-7 cells were more resistant to X-ray than TE-2 cells which is comparable to that obtained from the colony forming assay.