AW: [Histonet] Long term storage for IHC?

[Gudrun Lang]

I guess the formalin-fixation will be reversed although in a very slow
manner in the 70% ethanol. And I think, overnight fixation depending on the
tissue size will give insufficient formalin-fixation. This will result in
ethanol-fixation in the 70% and especially in the 100% ethanol.
If you want long time storage in ethanol, be sure that formalin-fixation is
sufficient. 
In my opinion your regular immunhistoprotocol has also to be adapted after
long time storage (more than 2 months), no matter if in formaldehyd or
ethanol.
What is more effort? Storage and administration of large numbers of wet
tissue in refrigerator or processing to paraffin blocks and storage in
drawers?

Gudrun Lang

-----Ursprüngliche Nachricht-----
Von: histonet-bounces <@t> lists.utsouthwestern.edu
[mailto:histonet-bounces <@t> lists.utsouthwestern.edu] Im Auftrag von Mikael
Niku
Gesendet: Samstag, 25. April 2009 22:25
An: histonet <@t> lists.utsouthwestern.edu
Betreff: [Histonet] Long term storage for IHC?

Dear Histonetters,

what do you think is the best way to store formalin-fixed tissues for 
immunohistochemistry, long-term (several years)?

We are currently fixing overnight, then rinsing in buffer and storing in 
70% or 100% ethanol, +4C or -20C. However, I don't really KNOW what 
happens here and how the tissues will work after the years. I guess 
basically the formalin fixation will be at least somewhat reversed and 
after some time the tissues will be more like ethanol fixed. But are 
there better options? Long term storage in formalin will make IHC 
difficult. And this is about large numbers of tissue samples, only some 
of which will be actually used later, so we wouldn't like to process all 
of them to paraffin either.

With best regards,
Mikael Niku
University of Helsinki, Finland

_______________________________________________
Histonet mailing list
Histonet <@t> lists.utsouthwestern.edu
http://lists.utsouthwestern.edu/mailman/listinfo/histonet