Barbetta Andrea, Massimi Mara, Conti Devirgiliis Laura, Dentini Mariella
Department of Chemistry, University of Rome La Sapienza, P.le A. Moro 5, 00185 Rome, Italy.
Biomacromolecules. 2006 Nov;7(11):3059-68. doi: 10.1021/bm060533l.
Highly open porous biodegradable scaffolds, based on gelatin A3, were fabricated with the aim of using them for tissue-engineering applications. The fabrication process is based on an emulsion-templating technique. In the preparation of gelatin scaffolds two different cross-linking procedures were adopted: (I) radical polymerization of the methacrylate functionalities, previously introduced onto the gelatin chains and (II) formation of isopeptide bridges among the gelatin chains promoted by the enzyme microbial transglutaminase. The method of cross-linking exerts a pronounced effect on the morphology of the porous biomaterials: radical polymerization of methacrylated gelatin allowed the production of scaffolds with a better defined porous structure, while the enzymatically cross-linked scaffolds were characterized by a thinner skeletal framework. A suitable sample of each kind of the differently cross-linked porous biomaterials was tested for the culture of hepatocytes. The scaffold obtained by radical polymerization possessed a morphology characterized by relatively large voids and interconnects, and as a consequence, it was more suitable for hepatocytes colonization. On the other hand, the enzymatically cross-linked scaffold resulted in less cytotoxicity and the cultured hepatocytes expressed a better differentiated phenotype, as evidenced by a greater expression and more correct localization of key adhesion proteins.
以明胶A3为基础，制备了高度开放的多孔可生物降解支架，旨在将其用于组织工程应用。制备过程基于乳液模板技术。在明胶支架的制备中，采用了两种不同的交联方法：（I）对预先引入明胶链上的甲基丙烯酸酯官能团进行自由基聚合，以及（II）通过酶微生物转谷氨酰胺酶促进明胶链之间形成异肽桥。交联方法对多孔生物材料的形态有显著影响：甲基丙烯酸化明胶的自由基聚合使得能够制备出具有更明确多孔结构的支架，而酶交联支架的特征是骨架框架较薄。对每种不同交联的多孔生物材料的合适样品进行了肝细胞培养测试。通过自由基聚合获得的支架具有以相对较大的空隙和互连为特征的形态，因此，它更适合肝细胞定植。另一方面，酶交联支架的细胞毒性较小，培养的肝细胞表现出更好的分化表型，关键粘附蛋白的表达增加和定位更正确证明了这一点。
