半乳糖化海藻酸钠-壳低聚糖微胶囊是如何包裹肝细胞的?  

Galactosylated alginate-chitosan oligomer microcapsule: How to encapsulate hepatocytes?

作　　者：田猛[1,2,3] 韩波[3] 游潮[1] 万昌秀[2] 

机构地区：[1]四川大学华西医院神经外科,四川省成都市610041 [2]四川大学高分子科学与工程学院生物医学工程系,四川省成都市610065 [3]南加州大学Keck医学院外科系,美国加利福利亚州洛杉矶市90032

出　　处：《中国组织工程研究》2013年第47期8215-8221,共7页Chinese Journal of Tissue Engineering Research

基　　金：国家自然科学基金项目(30870614);课题名称:第三代生物材料的生物学界面反应及其生物相容性和功能性评价方法的研究;成都市科技局&四川大学华西医院转化医学创新基金项目研究专项资助项目~~

摘　　要：背景:前期实验成功制备了一种新型半乳糖化海藻酸钠-壳低聚糖微胶囊,国内外尚未见以壳低聚糖和海藻酸钠制备的微胶囊用于肝细胞包裹的研究。目的:研究半乳糖化海藻酸钠-壳低聚糖微胶囊的结构和性能,然后将这种微胶囊用于肝细胞包裹,研究肝细胞的形态和功能表达。方法:激光共聚焦显微镜观察半乳糖化海藻酸钠含量分别为50%,30%时,半乳糖化海藻酸钠-壳低聚糖微胶囊的膜结构和膜厚,机械破碎百分率测定微胶囊的力学性能,通过包裹FITC标记的白蛋白和球蛋白的释放来测定微胶囊通透性。倒置相差显微镜观察肝细胞在半乳糖化海藻酸钠-壳低聚糖微胶囊中的形态,检测肝细胞白蛋白和尿素的合成。结果与结论:半乳糖化海藻酸钠-壳低聚糖微胶囊的膜内层致密而外层疏松,呈一种非对称膜的结构。随着半乳糖化海藻酸钠含量的增加,微胶囊的膜也越来越疏松,这些现象表明半乳糖的引入削弱了海藻酸钠分子链上负电荷的密度,影响了静电复合反应。微胶囊的力学性能与胶囊膜的结构和厚度有关;随着半乳糖化海藻酸钠含量的增加,膜结构越来越疏松,同时膜的厚度也减小,因此其力学性能变差。微胶囊的通透性主要决定于皮层的孔径,而疏松的亚层结构对通透性影响不大。制备的微胶囊具有选择性通过白蛋白,截留球蛋白的能力,表明胶囊膜的皮层孔径介于白蛋白和球蛋白尺寸之间。肝细胞在半乳糖化微胶囊中呈球形聚集体形态,并且肝细胞在半乳糖化微胶囊中的白蛋白分泌和尿素合成能力明显强于在海藻酸钠-壳低聚糖微胶囊中的效果。BACKGROUND： A novel galactosylated alginate-chitosan oligomer microcapsule has been prepared successfully.There is no report on hepatocytes encapsulated into the microcapsule prepared with chitosan oligomer and alginate sodium.OBJECTIVE： To study the structure and properties of the previous novel galactosylated alginate-chitosanoligomer microcapsule, and then explore the morphology and function expression of the hepatocytes encapsulated.METHODS： The membrane structure and thickness of the microcapsule（containing 50% or 30% galactosylated alginate） were observed using a laser confocal microscopy. Mechanical property was determined by mechanical rupture rate. Permeability was evaluated by release profile of fluoresceine isothiocyanate-labeled human serum albumin and immunoglobulin G. The morphology of hepatocytes in the microcapsule was observed using an inverted phase contrast microscopy. Function expression of the hepatocytes included albumin secretion and urea synthesis.RESULTS AND CONCLUSION： The microcapsule had an asymmetry structure, with dense inner and loosened outer surfaces. With the increase of the galactosylated alginate, the membrane became loose, which indicated the negative charge on the alginate molecular chains was weakened after introduction of galactose, and thus electrostatic complex was affected. Mechanical property was correlated with both membrane structure and thickness. With the increase of the galactosylated alginate, the membrane structure became loose and the thickness was decreased, resulting in poor mechanical properties. The permeability was dependent mainly on the pore size of the skin layer of the membrane other than the loose sublayer. The prepared microcapsule can selectively pass through the human serum albumin and cut off immunoglobulin G, indicating skin pore size between human serum albumin and immunoglobulin G. The hepatocytes can form sphere assemble in the galactosylated alginate-chitosan oligomer microcapsule and exhibit improved albumin secretion and urea syn

关 键 词：生物材料 生物材料与药物控释 药物控释材料 半乳糖 壳低聚糖 海藻酸钠 微胶囊 肝细胞 国家自然科学基金 

分 类 号：R318[医药卫生—生物医学工程]