Detection, enumeration, and characterization of immune cells infiltrating melanoma tumors.

Tumor-infiltrating immune cells have long been thought to affect tumor growth. In recent years, large retrospective studies have shown that the nature and polarization of the immune cells found within the tumor microenvironment impact not only the growth of the primary tumor, but also disease progression and patient survival. This has triggered considerable interest for an in depth analysis of the tumoral immune microenvironment and has created a need for standardized methods to characterize tumor-infiltrating immune cells. Here, we describe three approaches that can be used in mouse and human melanoma tumors.