[Histonet] GFAP IHC

[Nancy Herman]

We are using DAKO's ready-to-use GFAP antibody on our bovine tissue and using Envision+ HRP Rabbit detection system.  When using this antibody we see a brown color on the slide itself.  The staining was intense and quite uneven.  We have diluted the anitbody to 1:10 but there is still the brown slide.  The staining is not quite as uneven but appears more washed out.  We don't see this with any of our other antibodies we are using and our no primary controls for GFAP are clean.  Any advice or explanations for the slides picking up the brown color or improving GFAP IHC on bovine tissue?
Thanks

Nancy Herman
CFIA Lethbridge Laboratory
Lethbridge, Alberta