Hope that someone can help.  We have just begun using the antibody CD34 in 
our lab.  Our pathologists asked us to use skin as a control (even though the 
insert specified tonsil)  We are using a Ventana automated stainer, antigen 
retrieving in citra buffer by steamer, and then pretreating slides in H2O2. 
The patient tissue is staining nicely, but the positive skin control keeps 
washing off.  The negative  skin control stays on.  We also ran a positive 
tonsil today just to see what it would look like and there was no positive 
staining, but at least it stayed on.  Any ideas why the skin would be washing 
off ????  AND what does everyone else use for controls?

Thanks for your help
Jennifer Macias, HT (ASCP)
Western Reserve Care System-Forum Health
Youngstown, Ohio