Kathie
the answer is maybe.
It is difficult to tell, as it depends on the temperature, time of
exposure, the proteins in question and how dry the section was before
the paraffin was melted.  We used to routinely heat paraffin sections of
hard tissue but only after the section appeared dry to the eye. This
helped in section adhesion of the bone and dentin to the slide. With
these there did not seem to be any changes in staining or
immunochemistry compared to "non melted" sections.
I think you will just have to try it and see for the specific proteins
you are interested in. I would also run some other slides that have not
been heated as extra controls to make sure that you have the specificity
that you would normally expect.
Barry


Kathie Berghorn wrote:

> Dear Histonetters,
>         I am relatively new at using paraffin sections -- I had a
> student cutting paraffin sections over the weekend and to 'help'
> sections dry on the slide warmer after cutting, turned up the slide
> warmer enough that it melted the paraffin around the tissue.
>
>         My question is.... is the tissue still usable?  Did the heat
> damage proteins within the tissue affecting the antigenicity?
>
>         Thanking you in