primary astrocyte culture - infections (Dec/21/2010 )

hello,

I am a young scientist and for about a year now I have been trying to optimize my protocol to establish primary newborm rat astrocyte cell cultures.
The procedure an sich is not a problem, I am just having lots of problems due to infections.

I used have a lot of fungal infections but this problem seemed to be solved by adding some amphotericin B in my culture medium.
Today I discovered a yeast infection. This is the first time I encouter this. Does anyone know what it is coming from, how to avoid it or even how te clean my cultures from it?

many thanks

Yeasts are present on the hair and skin of everyone, it has most likely come from you or a co-worker or even from the rat you used to make the cultures.

With most cultures it is not worth eliminating the contamination - you are better off getting fresh cultures as the drugs used to treat the contamination affect how the cells behave and can cause cryptic contaminations to be present but not visible - which alter how the cells respond to treatments.

How do you sterilise the animal before extracting the brain?

Since we use the newborn rats at age 3-5 days, they are very small.

The only thing we do to minimize infection coming from the rat itself is that after decapitation, we put the head in 70% ethanol...
Do you think we should try something else?

thanks

You could try iodine swabs like they use in surgery, though 70% should also do it.