Ask the manufacturer of the antibody if it works on
1. formalin fixed, paraffin embedded sections.
2. formalin fixed, frozen sections.
3. unfixed sections.

Morphology will be much better if you can fix the tissue. If the antigen 
can survive fixation, its localization will be more accurate. Paraffin 
is not a fixative, it is an embedding medium.

Geoff

sanjeev francis wrote:

> I am interested in immunostaining mouse aortic cross-sections to look 
> for the tissue distribution of a particular protein.  I will be using 
> a polyclonal Ab.  My question is how to prepare the tissue sections.  
> I have read that frozen sections preserve the antigenic integrity of 
> tissues but have also heard that paraffin fixation is "milder" on the 
> tissue.  Which technique should I use to optimize my immunostaining?
>
> Thanks,
> Sanjeev Francis, MD
> Research Fellow
> Weill Medical College of Cornell University
>
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-- 
--
**********************************************
Geoff McAuliffe, Ph.D.
Neuroscience and Cell Biology
Robert Wood Johnson Medical School
675 Hoes Lane, Piscataway, NJ 08854
voice: (732)-235-4583; fax: -4029 
mcauliff@umdnj.edu
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