Multiplex Immunofluorescence Assays.

Multiplexed imaging platforms to simultaneously detect multiple epitopes in the same tissue section emerged in the last years as very powerful tools to study tumor immune contexture. These revolutionary technologies are providing a deep methodology for tumor evaluation in formalin-fixed and paraffin-embedded (FFPE) to improve the understanding of tumor microenvironment, new targets for treatment, prognostic and predictive biomarkers, and translational studies. Multiplexed imaging platforms allow for the identification of several antigens simultaneously from a single tissue section, core needle biopsies, and tissue microarrays. In recent years, multiplexed imaging has improved the abilities to characterize the different types of cell populations in malignant and non-malignant tissues, and their spatial distribution in relationship to clinical outcomes. Multiplexed technologies associated with digital image analysis software offer a high-quality throughput assay to study cancer specimens at multiple time points before, during and after treatment. The aim of this chapter is to provide a review of multiplexed imaging covering its fundamentals, advantages, disadvantages, and material and methods for staining applied to FFPE tumor tissues and focusing on the use of multiplex immunofluorescence with tyramine signal amplification staining for immune profiling and translational research.