摘要:
Increased yields of enzymes, particularly tissue plasminogen activator (tPA), are produced from cells, particularly CNCM I-222 cells, by a process using less concentrated lectin, particularly concanavalin A, in culture medium added to replace initial growth medium than has been used hitherto. After first harvesting of enzyme in supernatants, the culture can be reactivated by the addition of fresh culture medium containing an even lower lectin concentration, and a further harvest of enzyme obtained. The two harvests of enzyme together can give a greater overall yield than a single harvest after a single induction step employing the conventionally used higher lectin concentrations. Enzyme yield can be further increased by repeating the last incubation step once or twice to obtain one or two further harvests.
摘要:
A process for culturing biological material capable of multiplication, especially cells securely adhering to microcarriers, employs a bioreactor having a vessel for a culture medium having means for controlling the environmental conditions in the culture medium and a stirring device for the homogeneous distribution of the cells in the culture medium which has a rotary drive and a rotation axle running in the interior of the vessel, wherein the stirring device has at least one flat stirrer blade fixed on to the rotation axle and inclined to the rotation axle.
摘要:
The invention presents a method for the culturing of mammalian cells. This method involves the use of a bioreactor, which contains a sample of mammalian cells in a culture medium containing large molecules. Positioned inside the bioreactor is a semipermeable membrane which defines a space separated from the bioreactor by the semipermeable membrane. A nutrient medium flows through this separated space and, via virtue of the semipermeable nature of the separating membrane, nutrient pass therethrough into the culture medium, while cellular waste products pass into the separated space. The semipermeable membrane is selected so that the cells and large molecules, such as proteinaceous materials, cannot pass through the membrane, but remain in the bioreactor.