[Histonet] Alcohol fixation and immuno

[Martin, Erin]

Good morning everyone,
We occasionally receive specimens that were fixed in alcohol but processed on our machine, which starts in formalin.  In our typical antigen retrieval we either use a 95 degree waterbath for an hour or enzyme for 5 minutes.  On alcohol fixed tissues this chews up the tissue but we get staining.  If we repeat the stains with no retrieval to try to minimize the damage, we get very weak or no staining at all (in a general sense - I'm not speaking about any particular antibody).  Is this because we have a small degree of formalin fixation because of the formalin step on the processor?  Enough to require some retrieval but not as much as formalin fixed tissue?  Has anyone else run into this problem?  If so, how did you solve it?

Thank you for you help!
Erin Martin
UCSF Dermatopathology