Wittmer Corinne R, Phelps Jennifer A, Lepus Christin M, Saltzman William M, Harding Martha J, Van Tassel Paul R
Department of Chemical Engineering, Yale University, New Haven, CT 06520-8286, USA.
Biomaterials. 2008 Oct;29(30):4082-90. doi: 10.1016/j.biomaterials.2008.06.027. Epub 2008 Jul 23.
Multilayer nanofilms, formed by the layer-by-layer (LbL) adsorption of positively and negatively charged polyelectrolytes, are promising substrates for tissue engineering. We investigate here the attachment and function of hepatic cells on multilayer films in terms of film composition, terminal layer, rigidity, charge, and presence of biofunctional species. Human hepatocellular carcinoma (HepG2) cells, adult rat hepatocytes (ARH), and human fetal hepatoblasts (HFHb) are studied on films composed of the polysaccharides chitosan (CHI) and alginate (ALG), the polypeptides poly(l-lysine) (PLL) and poly(l-glutamic acid) (PGA), and the synthetic polymers poly(allylamine hydrochloride) (PAH) and poly(styrene sulfonate) (PSS). The influence of chemical cross-linking following LbL assembly is also investigated. We find HepG2 to reach confluence after 7 days of culture on only 2 of 18 candidate multilayer systems: (PAH-PSS)(n) (i.e. nPAH-PSS bilayers) and cross-linked (PLL-ALG)(n)-PLL. Cross-linked PLL-ALG and PLL-PGA films support attachment and function of ARH, independently of the terminal layer, provided collagen is adsorbed to the top of the film. (PAH-PSS)(n), cross-linked (PLL-ALG)(n), and cross-linked (PLL-PGA)(n)-PLL films all support attachment, layer confluence, and function of HFHb, with the latter film promoting the greatest level of function at 8 days. Overall, film composition, terminal layer, and rigidity are key variables in promoting attachment and function of hepatic cells, while film charge and biofunctionality are somewhat less important. These studies reveal optimal candidate multilayer biomaterials for human liver tissue engineering applications.
通过带正电和负电的聚电解质逐层（LbL）吸附形成的多层纳米膜是组织工程中有前景的基质。我们在此从膜组成、终端层、刚性、电荷和生物功能物种的存在等方面研究肝细胞在多层膜上的附着和功能。对由多糖壳聚糖（CHI）和藻酸盐（ALG）、多肽聚（L-赖氨酸）（PLL）和聚（L-谷氨酸）（PGA）以及合成聚合物聚（烯丙胺盐酸盐）（PAH）和聚（苯乙烯磺酸盐）（PSS）组成的膜上的人肝癌细胞（HepG2）、成年大鼠肝细胞（ARH）和人胎儿肝母细胞（HFHb）进行了研究。还研究了LbL组装后化学交联的影响。我们发现，在18种候选多层系统中，只有2种上培养7天后HepG2能达到汇合状态：（PAH-PSS）（n）（即n个PAH-PSS双层）和交联的（PLL-ALG）（n）-PLL。交联的PLL-ALG和PLL-PGA膜支持ARH的附着和功能，与终端层无关，前提是胶原蛋白吸附在膜的顶部。（PAH-PSS）（n）、交联的（PLL-ALG）（n）和交联的（PLL-PGA）（n）-PLL膜都支持HFHb的附着、层汇合和功能，后一种膜在8天时促进的功能水平最高。总体而言，膜组成、终端层和刚性是促进肝细胞附着和功能的关键变量，而膜电荷和生物功能则不太重要。这些研究揭示了用于人类肝脏组织工程应用的最佳候选多层生物材料。
