I want to do a co-labelling immunofluorescence experiment on mouse parafin-embedded tissue sections. The first primary antibody is a Anti-X raised in rabbit, IgG fraction and the second primary is Anti-Y raised in mouse. Since I know there can be issues with background staining using mouse monoclonal antibodies in mouse tissues, I'm not sure how I can account for this in my double staining protocol. I have optimized the protocol for Anti-X using a goat anti-rabbit secondary but haven't tried the mouse Anti-Y antibody yet since the tissue sections I have are valuable and can't be wasted. Can someone help with ideas/protocol to double stain with these primaries?