[Histonet] Nuclear artefacts in FFPE tissues

[James S.]

I've been attempting to do some multi-colour fluorescence labelling of FFPE lymphoma tissue - usually I only use frozen tissue. It was all going smoothly on some FFPE tonsil sections but with the lymphoma tissues I see punctate nuclear staining with an epitope that should not be nuclear (CD32) - in some samples it appears as punctate staining all over the nuclei but in other samples it appears as a perinuclear halo. It only occurred with one particular antibody (rabbit anti-CD32) and not with rabbit anti-CD20 or mouse anti-CD68. Could this staining just be an artefact - is this common with FFPE tissue and is there something I can do to get rid of it.

Thanks
Sonya