海藻酸钠水凝胶中粘附位点及空间构建促进MG-63细胞铺展及成骨分化  

The Construct of Cell Adhesion Sites and Degradation Space in Alginate Hydrogels to Enhance Spreading and Osteogenic Differentiation of MG-63 Cells

作　　者：孙静[1] 卫丹[1] 朱禹达 钟美玲[1] 左一聪 范红松[1] 

机构地区：[1]四川大学国家生物医学材料工程技术研究中心,四川成都610064

出　　处：《中国材料进展》2013年第10期623-630,共8页Materials China

基　　金：国家自然科学基金资助项目(81071272;51273121)

摘　　要：细胞粘附与铺展是三维水凝胶基质中贴壁依赖型细胞存活所必须的两个条件,将细胞粘附位点的引入和凝胶中细胞铺展空间的构建相结合,提出了同时含有RGD多肽和明胶微球的粘附型大孔水凝胶模型,以促进细胞在其中的铺展与分化。该模型采用光交联海藻酸钠水凝胶为基础,同时引入RGD多肽和明胶微球,通过RGD多肽的共价接枝为细胞粘附提供前提,利用明胶微球在37℃下的快速降解性,为细胞的进一步增殖和铺展以及分化提供所需空间。结果显示,明胶微球的加入提高了凝胶的力学性能,同时降低了凝胶的溶胀率。RGD和明胶微球的引入能够很好地支持MG-63细胞在其中的增殖、粘附与铺展,并显著提高其碱性磷酸酶活性,上调成骨相关基因(BMP-2,COL-I和OCN)的表达。而在不含微球的RGD-ALG和ALG凝胶中,细胞铺展及成骨分化均受到很大抑制。Adhesion and spreading of anchorage-dependent cells are two essential factors for their subsequent settlement and commitment in 3D hydrogel substrate. An adhesive macroporous alginate hydrogel system was suggested here to over- come the low cell affinity and high cell constraint of hydrogel substrates for cells encapsulated in them. RGD peptide was grafted onto the alginate molecule to support cell adhesion and gelatin microspheres were introduced into photocrosslinked alginate hydrogels to create macropores by their degradation at 37~C for cell spreading and facilitate cell ingrowth as well as prolonged cell survival within hydrogels. With the incorporation of gelatin microspheres, the hybrid alginate hydrogels ex- hibited significantly enhanced mechanical properties and decreased swelling ratios. MG-63 cells in alginate hydrogel coop- erated with RGD and gelatin microspheres exhibited a rapid proliferation and spread gradually with prolonged culture time, and their osteogenic differentiation was greatly facilitated, such as the high expression of BMP-2, COL-I and OCN genes. While in the pure alginate hydrogel （ALG） and hydrogels only capable of cell affinity （ RGD-ALG）, cells could just ex- hibit either a rounded shape or a spreading morphology with a very limited degree, and the osteogenic differentiation was also inhibited.

关 键 词：水凝胶 明胶微球 RGD 细胞铺展 成骨分化 

分 类 号：R318.08[医药卫生—生物医学工程]