Kim, I assume they are going to run the slide like an EM sample and then put
their molds right over the areas of interest. Morpholgy of a paraffin
sections won't be much different than a frozen section when viewed by EM -
the paraffin makes huge holes in the tissue when seen at the EM level. What
may make a difference in your immuno staining is the fixation before you
stain. Is your antigen likely to diffuse on a cryostat section?

Tim Morkne
CDC, Atlanta



-----Original Message-----
From: Kimberly L Merriam [mailto:kmerriam@tktx.com]
Sent: Thursday, August 23, 2001 5:18 PM
To: Histonet
Subject: EM sample prep


Hi all,

I have been asked to prepare IHC-stained slides for EM.
What I was told to do (by the EM lab we are working with) is
to stain cryostat sections with my antibodies (a directly
biotinylated primary and immunogold secondary), then
post-fix them in glutaraldehyde/sodium cacodylate fixative
and send them to the EM lab for further processing.

Here are my questions:  Do these samples need to be cryostat
or can I do this with paraffin?  Wouldn't paraffin-embedded
samples have better morphology?

I have never done any type of EM, so I am clueless!

Thanks,
Kim Merriam