Department of Cell Technologies and Applied Stem Cell Biology, Biomedical-Biotechnological Center, Medical Faculty, University Leipzig, Deutscher Platz 5, Leipzig 04103, Germany.
Biomaterials. 2009 Nov;30(33):6514-21. doi: 10.1016/j.biomaterials.2009.08.024. Epub 2009 Sep 2.
Biomaterials can potentially influence stem and progenitor cell proliferation and differentiation in both a positive and a negative way. Herein, we report on the expansion and differentiation of rat embryonic (E17) liver (RLC-18) cells on new bioactive membrane made of PEEK-WC-PU, whose surface was grafted with nitrogen functionalities by means of NH(3) glow discharges. The performance of the developed membrane was evaluated by analyzing the expression of the liver specific functions of cells cultured in a 6-well gas-permeable bioreactor. It was found that native and NH(3) plasma-grafted PEEK-WC-PU membranes enabled expansion of liver cells in the bioreactor. Liver embryonic cells on the membranes exhibited higher functional activities compared to those cultured on conventional culture dishes as demonstrated by higher albumin and urea production. They showed gene expression of alpha-fetoprotein and albumin in a time-dependent manner of the hepatic differentiation process. LDH assay and SEM analyses revealed that a high number of viable liver stem cells attached to the membranes. Unexpectedly, liver progenitors cultured on membranes had higher telomerase activity than ones in the plates, preventing cell senescence. Thus, membranes are able to sustain in vitro the same in vivo liver functions and to allow the expansion of progenitor cells.
生物材料可以通过正负两方面来潜在地影响干细胞和祖细胞的增殖和分化。在此，我们报告了一种新型的生物活性膜的大鼠胚胎（E17）肝脏（RLC-18）细胞的扩增和分化，该膜由 PEEK-WC-PU 制成，其表面通过 NH3 辉光放电接枝了氮官能团。通过分析在 6 孔透气生物反应器中培养的细胞的肝脏特异性功能的表达来评估所开发膜的性能。结果发现，天然和 NH3 等离子体接枝的 PEEK-WC-PU 膜可在生物反应器中扩增肝脏细胞。与在常规培养皿中培养的细胞相比，膜上的肝胚胎细胞表现出更高的功能活性，表现为白蛋白和尿素的产生更高。它们表现出α-胎蛋白和白蛋白的基因表达，呈时间依赖性的肝分化过程。LDH 测定和 SEM 分析表明，大量有活力的肝干细胞附着在膜上。出乎意料的是，与在平板上培养的细胞相比，在膜上培养的肝祖细胞具有更高的端粒酶活性，从而防止细胞衰老。因此，该膜能够在体外维持与体内相同的肝脏功能，并允许祖细胞的扩增。
