High-density culture of FM-3A cells using a bioreactor with an external tangential-flow filtration device

Abstract

A novel bioreactor system developed for high-density cultures of suspended mammalian cells is described using a tangential-flow filtration device outside the culture vessel to separate viable cells from spent medium. The filtration device is based on thin porous microfiltration membranes with a pore size of 0.20-0.65 microns. Because cells have a diameter of about 10-20 microns, they cannot permeate these membranes with the spent medium. So, allowing a perfusion culture to be created using this system. In most membrane filtration systems, clogging of the membranes has made long-term operation difficult. In this system, however, high pressure is not applied directly to the membrane, thus minimizing clogging. Also, clogging of the membrane was prevented by washing the membrane surface once a day, and increasing the membrane surface area. With this system, FM-3A cells were cultured and maintained at a high density of 3.0 x 10(7) cells/ml for two weeks, and a continuous culture was supported for as long as 34 days.

Potential of cell retention techniques for large‐scale high‐density perfusion culture of suspended mammalian cells

“…In this system, the flow rate in the retention loop has to be optimized in order to minimize fouling and to avoid shearinduced disruption of the cells. Despite membrane rinsing or back-flushing, authors reported frequent fouling and clogging problems (de la Broise et al, 1991(de la Broise et al, , 1992Kawahara et al, 1994). Attempts to increase the efficiency of this technique were mainly conducted to increase membrane surface and tangential flow through module design, using channels in zigzag (de la Broise et al, 1991(de la Broise et al, , 1992 or spiral (Caron et al, 1994).…”

“…This principle was tested by several investigators at small scale using specifically built modules with membranes in PVDF (Kawahara et al, 1994), Nucleopore (de la Broise et al, 1991Broise et al, , 1992, and polycarbonate (Caron et al, 1994). In this system, the flow rate in the retention loop has to be optimized in order to minimize fouling and to avoid shearinduced disruption of the cells.…”

Perfusion Processes

“…depth filter (de la Broise et al 1991;Velez et al 1989;Caron et al 1994;Kawahara et al 1994). The tangential movement reduces the filter fouling since the particles are not pressed into the filter membrane.…”

Separation of CHO cells using hydrocyclones

“…Filtration-based techniques present problems of filter fouling after a relatively short period of operation (Kawahara et al 1994;Van Reis and Zydney 2001). Centrifuges may suffer from cell adhesion and clogging, besides their high mechanical complexity and high cost (Jäger 1992;Tokashiki et al 1990).…”