Yamaji H, Fukuda H
Engineering Research Laboratories, Kaneka Corporation, Hyogo, Japan.
Appl Microbiol Biotechnol. 1994 Dec;42(4):531-5. doi: 10.1007/BF00173916.
The growth kinetics of anchorage-independent animal cells [mouse myeloma MPC-11 (ATCC CCL 167)] immobilized within porous polyvinyl formal resin biomass support particles (BSPs; 3 x 3 x 3 mm cubes; mean pore diameter, 60 microns) was analyzed by measuring intracellular and extracellular lactate dehydrogenase (LDH) activities in a perfusion culture. First, the intracellular LDH content of cells immobilized within the BSPs was assayed in a shake-flask culture and found to remain almost comparable to that of non-immobilized cells in the exponential growth phase under static culture. Then, cells inoculated in the BSPs were grown in a continuous stirred-tank bioreactor. Using the LDH content of non-immobilized cells, the density of immobilized cells and the numbers of leaked and dead cells were evaluated, respectively, by the intracellular LDH activity of immobilized and leaked cells and the LDH activity in cell-free culture supernatant. In the initial period, immobilized cells exhibited exponential growth at a constant apparent specific growth rate; however, the actual specific growth rate, which takes into consideration cell death and cell leakage, decreased significantly. In the stationary phase, the actual specific growth rate maintained a constant but markedly lower value than during exponential growth.
通过测量灌注培养中细胞内和细胞外乳酸脱氢酶（LDH）的活性，分析了固定在多孔聚乙烯醇缩甲醛树脂生物质支持颗粒（BSPs；3×3×3毫米立方体；平均孔径60微米）内的非贴壁动物细胞[小鼠骨髓瘤MPC-11（ATCC CCL 167）]的生长动力学。首先，在摇瓶培养中测定固定在BSPs内的细胞的细胞内LDH含量，发现在静态培养的指数生长期，其与未固定细胞的细胞内LDH含量几乎相当。然后，接种在BSPs中的细胞在连续搅拌罐式生物反应器中生长。利用未固定细胞的LDH含量，分别通过固定化细胞和泄漏细胞的细胞内LDH活性以及无细胞培养上清液中的LDH活性来评估固定化细胞的密度以及泄漏细胞和死亡细胞的数量。在初始阶段，固定化细胞以恒定的表观比生长速率呈指数生长；然而，考虑到细胞死亡和细胞泄漏的实际比生长速率显著下降。在稳定期，实际比生长速率保持恒定，但明显低于指数生长期。
