3 replies to this topic

[Damour]

I apologize if this I am writing under wrong topic, but this is concerning mammalian cell culture in small scale STR's.

In long-term continuous cultivations (or shorter fed-batch cultivations with aged cells) I have observed a significant decrease in productivity when using mammalian cells.

I am referring to cells which have been continuously cultivated in a bioreactor for at least 1 month, or cells that have been passaged for at least 2 months and then inoculated into a bioreactor.

I have also observed a significant increase in cell growth rate.

How does cell age affect productivity and cell growth rate?

thank you

[bob1]

Have a look for this paper:  Mortality and Immortality at the Cellular Level. A Review. L. Hayflick, 1997.

[Damour]

bob1, on 10 October 2012 - 12:12 PM, said:

Have a look for this paper:  Mortality and Immortality at the Cellular Level. A Review. L. Hayflick, 1997.

Yes, I have read some of Hayflick's work and I accept his argumentation about molecular disorder, longevity and replicometer. However, I still dont feel that I can explain the fact that the growth rate increased significantly with cell age. I believe I observed the "hayflick limit" when cultivation the oldest cells, but I do not understand the high cell growth rate prior to that limit.

[bob1]

besides cells reaching the Hayflick limit, you will also be getting a sub population of (a) cell(s) that have transformed - hence the growth rate.  This event is rare, about 1 in 10^7 cells will transform.