HepG2 cells, ideal passage number for western blot - (Jul/21/2006 )

Dear colleagues,

For HepG2 cells, is there an ideal passage that people use to prepare their samples for
protein determination (e.g Western Blotting)?

Would too high of a passage cause some proteins not to be expressed (due to
mutation)?

The HepG2 cells that was sent to our lab is in passage 85, and I am using
passage 89 for my experiment. Is passage 89 still okay for protein
determination?

Thanks!!

Hi.

I cultured HepG2 before and I did western blot for several proteins such as phospho-CREB, HMG-CoA reductase. LDL receptor, etc. It seemed to me the passage number wasn't that critical. At least for those proteins I checked were stable.
I usually brought up new cells when the cells started growing too many "clumps".