Richard,

If the frozen sections have benn fixed in ethanol and not been in contact
with formalin, then I would probably not retrieve. Even a short time in
formalin may not be a problem (ie urgent frozen sections that are "fixed"
in formalin tend to be only for a very short time ?1minute or less and the
crosslinking probably may not have occured).
Would it be possible to try on another case that has been frozen
sectioned, stained H&E and yet has confirmed positive staining on
parraffin sections?
Regards,
Tony Henwood JP, BappSc, GradDipSysAnalys, CT(ASC)
Laboratory Manager
The Children's Hospital at  Westmead,
Locked Bag 4001, Westmead, 2145, AUSTRALIA.
Tel: (02) 9845 3306
Fax: (02) 9845 3318

>>> Richard Cartun <Rcartun@harthosp.org> 28/February/2001 06:20am
>>>
Has anyone tried doing heat-induced epitope retrieval on de-stained
(H&E) frozen tissue sections?  I have been asked to stain two frozen
section slides, one for ER (clone 6F11) and one for TTF-1 (clone
8G7G3/1) because there is no tumor left in the permanent sections. 
Thanks!

R. Cartun