Yeast Contamination - Serum vs. Serum Free Media - (Feb/13/2008 )

I have been growing a primary line of cardiomyocytes that I purchased for about a month. The company supplies two types of media for cell growth and culture, one media contains serum, the other is serum free. Every time I switch my cells from the media with serum to the serum free media, I develop a yeast contamination. My question is: Is it possible that the cells themselves are carrying the contamination, and the serum media is inhibiting it's growth? Or could it be that the serum free media I purchased is contaminated? Is there a way to determine if the cell line is contaminated?

It is possible that the cell line does have a contamination. Have you tried testing the media for contamination? If that comes up positive, than most likely it is your cells that are contaminated.

Hope that helps.

Have you tried just putting small samples of the media in the incubator and seeing if anything grows? Test both media. It could be that the serum media has the contamination that is suppressed by the the other things in the media and when you change it gives the infection chance to grow.
If you fix your cells and stain with DAPI and see any blue dots with in the cells (but not the nucleus) it might tell you that you've got something else aside from your cells- I use this for testing for mycoplasma. If should work for yeast I would think. I'm not sure if you have a yeast infection in your cells- I would look at the media before making that choice

Another thought- are these cells- fresh from the manufacturer or have you made stocks and are using those?

Good Luck