How long can viably frozen cells stay good in -80 degree? - (Oct/14/2009 )

I heard some people keep viably frozen cells in -80 freezer for years. Can cells be stored in -80 for that long?

Yup - recently unthawed some cells that were frozen in 2003. They were quite healthy!

Good to know! We have a very mal-designed liquid nitrogen tank and I am trying to avoid using it too frequently.

It depends on the cell type... some are tougher than others.

It is best not to store them at -80 for too long, they will degrade and any cells you get out of a tube older than about a year are quite likely to be different to the population you put in there. If you need to store them at -80, make sure you get them up every 6 months of so and re-freeze them to ensure that they are as similar to the original population as possible.

depends on your cell type and the using frequency of freezer. I usually store the frozen cells in -80 no more than 3 months.

We ve stored the cells in -80 now for 4 long years now and every 6 months do teh basic characterization tests to see if they are still in a healthy shape. Basic ch will include things like viability, if its a recombinant host, then the DNA insert etc!!!