adaptation to different medium? - (Aug/18/2008 )
how long would it take for a cell line to adapt to a change in medium (I will begin with adding small percentages of one medium diluted in the other and gradually increase the amount of "unusual medium)?
The thing is that upon doing experiments in 2 different cell lines I noticed a difference in result and upon trying to exclude a lot of other factors I tried to do the experiment in different media (as one cell line is a suspension cell line grown in RPMI and the other is an adherent line grown in DMEM, the serum used for both cell lines is from the same batch (even the same bottle!)) and in the suspension cell line I got the "DMEM-phenotype" and in the adherent line I got the 'RPMI-phenotype". I stress that this is performed just once but I am going to do a lot of repeats etc and include the necessary controls (flow cytometric detection of expression levels of severall membrane proteins involved in the process I'm studying, analysing growth of the cells in the different media, check for cell cycle at different time points using PI-staining and flow cytometry etc).
Apart from this, I believe that the expression levels of the membrane proteins will not be the issue, as for the experiment I performed last week I just counted the cells, spinned them down and changed medium and carried on with the experiments right away, so I didn't "give the cells time to alter their expression" (though I will obviously check this!).
I'm not really sure how much this helps: but I've adapted a cell line to different type of serum and I've found diluting by 50% for each passage didn't drop the cell viability too much and they were pretty happy.
Like I said, I'm not entirely sure if that really answers your question.. but I tried.