Process Sciences, Global Manufacturing Sciences, Biogen International GmbH, Solothurn, Switzerland.
Process Sciences, Global Manufacturing Sciences, Biogen, Research Triangle Park, Durham, North Carolina, USA.
Biotechnol Prog. 2020 Nov;36(6):e3040. doi: 10.1002/btpr.3040. Epub 2020 Jul 9.
Mammalian cells were grown to high density in a 3,000 L culture using perfusion with hollow fibers operated in a tangential flow filtration mode. The high-density culture was used to inoculate the production stage of a biomanufacturing process. At constant permeate flux operation, increased transmembrane pressures (TMPs) were observed on the final day of the manufacturing batches. Small scale studies suggested that the filters were not irreversibly fouled, but rather exposed to membrane concentration polarization that could be relieved by tangential sweeping of the hollow fibers. Studies were undertaken to analyze parameters that influence the hydrodynamic profile within hollow fibers; including filter area, cell density, recirculation flow rate, and permeate flow rate. Results indicated that permeate flow rate had the greatest influence on modulating TMP. Further evaluation showed a significant decrease in TMP when permeate flow was reduced, and this occurred without any negative effect on cell growth or viability. Hence, a 30% reduction of permeate flow rate was implemented at manufacturing scale. A stable operation was achieved as TMP was successfully reduced by 75% while preserving all critical factors for performance in the perfusion bioreactor.
哺乳动物细胞在使用中空纤维进行灌注的 3000L 培养物中生长到高密度，中空纤维以切向流过滤模式运行。高密度培养物用于接种生物制造过程的生产阶段。在恒透过通量操作下，在生产批次的最后一天观察到跨膜压力（TMP）增加。小规模研究表明，过滤器没有不可逆地堵塞，而是暴露于膜浓差极化，可以通过中空纤维的切向吹扫来缓解。进行了研究来分析影响中空纤维内流体动力学特性的参数；包括过滤器面积、细胞密度、再循环流速和透过流速。结果表明，透过流速对调节 TMP 的影响最大。进一步的评估表明，当透过流速降低时，TMP 会显著降低，而这对细胞生长或活力没有任何负面影响。因此，在生产规模上实施了 30%的透过流速降低。通过成功降低 75%的 TMP 实现了稳定的操作，同时保留了灌注生物反应器中所有性能的关键因素。
