The Visium CytAssist Spatial Gene and Protein Expression assay is designed to analyze mRNA and protein expression in tissue sections derived from formalin fixed & paraffin embedded (FFPE) tissue samples. A single CytAssist run accommodates up to two tissue slides (tissue placed on a standard glass slide) as sample input. This protocol outlines deparaffinization, decrosslinking, immunofluorescence (IF) staining, and imaging of FFPE tissue for use with 10x Genomics Visium CytAssist Spatial Gene Expression assay.