Wu Dan-Qing, Zhang Guo-Liang, Shen Chong, Zhao Qian, Li Hui, Meng Qin
Department of Chemical Engineering and Biochemical Engineering, Zhejiang University, 38 Zheda Road, Hangzhou 310027, Zhejiang Province, China.
World J Gastroenterol. 2005 Mar 21;11(11):1599-604. doi: 10.3748/wjg.v11.i11.1599.
To investigate diffusion in mammalian cell culture by gel entrapment within hollow fibers.
Freshly isolated rat hepatocytes or human oral epidermoid carcinoma (KB) cells were entrapped in type I collagen solutions and statically cultured inside microporous and ultrafiltration hollow fibers. During the culture time collagen gel contraction, cell viability and specific function were assessed. Effective diffusion coefficients of glucose in cell-matrix gels were determined by lag time analysis in a diffusion cell.
Significant gel contractions occurred in the collagen gels by entrapment of either viable hepatocytes or KB cells. And the gel contraction caused a significant reduction on effective diffusion coefficient of glucose. The cell viability assay of both hepatocytes and KB cells statically cultured in hollow fibers by collagen entrapment further confirmed the existence of the inhibited mass transfer by diffusion. Urea was secreted about 50% more by hepatocytes entrapped in hollow fibers with pore size of 0.1 mum than that in hollow fibers with MWCO of 100 ku.
Cell-matrix gel and membrane pore size are the two factors relevant to the limited mass transfer by diffusion in such gel entrapment of mammalian cell culture.
通过中空纤维内的凝胶包埋法研究哺乳动物细胞培养中的扩散情况。
将新鲜分离的大鼠肝细胞或人口腔表皮样癌(KB)细胞包埋于I型胶原溶液中,并在微孔和超滤中空纤维内进行静态培养。在培养期间,评估胶原凝胶收缩、细胞活力及特定功能。通过在扩散池中进行滞后时间分析,测定葡萄糖在细胞 - 基质凝胶中的有效扩散系数。
无论是活的肝细胞还是KB细胞被包埋后,胶原凝胶均发生显著收缩。且凝胶收缩导致葡萄糖的有效扩散系数显著降低。通过胶原包埋在中空纤维中静态培养的肝细胞和KB细胞的细胞活力测定,进一步证实了扩散导致的传质受限现象的存在。孔径为0.1μm的中空纤维中包埋的肝细胞分泌的尿素比截留分子量为100ku的中空纤维中的肝细胞多约50%。
细胞 - 基质凝胶和膜孔径是与哺乳动物细胞培养这种凝胶包埋法中扩散传质受限相关的两个因素。