Hi John,

did you use the same slide-type all the time?

We are having actually a serious similar problem with patchy staining 
with several antibodies, but not all. It seems to correlate with a change 
 from Superfrost Plus slides to Slides called "Histobond". The tissue 
sections stick to the slides as nicely as before, and they cost onyl half 
the price. This is why we changed to this other brand. However, now, not 
just looking for tissue adherance but also evaluating immunohistochemical 
staining properties, we seem to have a difference with patchy stainign as 
you described. Next week I'll perform more experiments to come to a final 
conclusion comparing different tissues sections on both slide types in 
parallel etc.

Heike