Thank you to all who replied!

It seems like the good news is that I don't need to make any changes to my paraffin. 

As the reference was a 2002 book which was recently recomended here on histonet, I thought maybe somebody knew something I hadn't heard of yet.

I think I have enough comments printed out to appease my Immuno Pathologist if he comes across this reference like I did.

Thank you all

Ross Stapf


>>> "J. A. Kiernan"  10/18/02 01:18AM >>>
Ross Stapf (or was it Patsy Ruegg) wrote:
> On searching ... why heat in paraffin ... might be more 
> detrimental than heat in antigen retrieval solution.
> ... can't find if anyone came to a conclusion that this was true ...
> I'm sure someone has studied this in order to come up with this 56

The cited temperature 56C must mean that this is another urban
laboratory
legend!  Anyone studying effects of wax temperature would
investigate
steps such as 50-55-60. An investigation with a precision of one
degree would need 20 lots of trials to cover the range, and what
agency would fund such a study? 

Several anecdotal Histonet replies have reported exactly the 
opposite - that temperatures well above the mid-50s does more 
good than harm when it comes to detecting antigens
immunohistochemically.
These informal reports, based on firt-hand experience, carry much
more
weight than "someone said that..." or a photocopy of some piece
of
paper found in a cardboard box. 

There is also a Common Wisdom of Immunohistochemistry that says
coagulation of proteins by heat or coagulant fixatives liberates
the epitopes of insolubilized protein molecules.
 
If the routine fixative everywhere was a simple alcohol-acetic
mixture, would there be any of these problems with masked
antigens?

-- 
-------------------------
John A. Kiernan
Department of Anatomy and Cell Biology
The University of Western Ontario
London,   Canada   N6A 5C1
   kiernan@uwo.ca 
   http://publish.uwo.ca/~jkiernan/