壳聚糖纳米纤维电纺膜体外对肝细胞作用的研究

Effects of Chitosan Nanofiber Scaffold on Hepatocytes in vitro

生物人工肝作为肝功能衰竭的一种有效支持手段，近年来得到很大的进展，但如何长期维持其中肝细胞的活性及功能一直是困扰人们的难题。纳米生物材料的应用为这一问题的解决提供了可能的方案。用静电纺丝的方法将壳聚糖制备成纳米纤维电纺膜，同时采用经典的两步原位胶原酶灌注法分离大鼠肝细胞，观察肝细胞在纳米纤维电纺膜表面的形态，同时检测其活性和功能。肝细胞在壳聚糖纳米纤维电纺膜表面展示了良好的活性，并能与支架材料紧密结合。其尿素合成、蛋白分泌及细胞色素P450的活性均为对照组的1．5—2倍，糖原合成也较对照组有明显增强。壳聚糖纳米纤维电纺膜能促进肝细胞黏附，同时具有良好的生物相容性，从而促进肝细胞的功能，是生物反应器中肝细胞黏附介质的理想材料。

As a useful means of temporary liver support for patients awaiting liver transplantation, bioartificial liver （BALI has made great progress in recent years. However, how to enhance the cell attachment and promote the liver functions of hepatocyte remains one of the major chanllenges in BAL. The application of nanofiber scaffold may afford possible solution to this problem. A new chitosan nanofiber scaffold was designed via electrospinning, and the rat hepatocytes were harvested by a two-step in situ collagenase perfusion procedure. Effects of the scaffold on hepatocyte adhesion, viability and function were then investigated. It was showed that hepatocytes on chitosan nanofiber scaffold exhibited better viability and tighter cell-substrate contact than cells on regular chitosan film. In addition, urea synthesis, albumin secretion and cytochrome P450 activity of hepatocytes on chitosan nanofiber scaffold were all 1.5 to 2 folds higher than the controls. Glycogen synthesis was also increased compared with the controls. The new nanofiber scaffold demonstrated superior abilities in cell adhesion and biocompatibility to improved the functions of hepatocytes, which suggested its potential application as a substratum for hepatocytes culturing in bioreactors.