PFA fixed, sucrose dehydration then cryosectioned. Is the tissue usable for immu - (Jan/21/2015 )

So I treated my tissue quite differently from other protocols and wanted to know whether it would still be usable for immunofluorescence staining? I fixed a fresh small block of liver tissue in 4% PFA (without perfusing) and then did a 15, 20, 30% sucrose gradient and subsequently cryosectioned it. I've since kept it in -20C. 

Most protocols I've looked at, the tissue was either snap frozen or perfused and sucrose dehydrated prior to cryosectioning. 

What is the best way to prepare (mouse) liver for immunofluorescence staining?

Yep, it is usable. It is over-processed for IF purposes (snap freezing in OCT would have sufficed), but there should be no deterioration of antigens.