[Histonet] Strange circles in IHC slides

[V. Neubert]

Those appear in all 14 slides I stained - I doubt to have made the same 
mistake of leaving bubbles fourteen times when mounting them.


> That my friend is the result of a air bubble on the section. If it had
> been unremoved xylene the hematoxylin would have been absent as well.

> I have seen something (rarely) like this.  We always assume that a few
> bubbles developed that impeded the flow of one or more critical reagents
> to the tissue underlying the bubble.  Somehow, the impediment vanished
> later in staining to allow for the Hematoxylin counterstain to take.  It
> would only take the omission of one reagent to halt the immunochemical
> reaction in that area.  Just a thought.