Embryo preservation for IHC at RT?? - (Apr/02/2010 )
I have recently switched labs and will now have to do some immunostainings on sections as well as whole mount mouse embryos (dpc 10-12). I have never done this before, so I am not really aware of the importance of the storing conditions. So here is what they have done:
Embryos were dissected in PBS, fixed in 4% PFA for minimum 2 h. Then they were returned to PBS and kept at RT. They have been at RT for several weeks now, and the experiments are planned to be performed in a few weeks, so they will have been at RT for at least two months.
Does anybody have an idea if we will still be able to get good results from these samples? I have checked several protocols, and it seems that most of the time the specimens are kept in MetOH at -20°C, which would make more sence to me.
PFA seems to work for a short while (a week or so) at 4 degrees C before the crosslinking starts to break apart. The storage conditions your lab has been using may not affect the things you are looking at, but I have found it is best to store appropriately.