Deciphering functional tumor-immune crosstalk through highly multiplexed imaging and deep visual proteomics

Summary Deciphering the intricate tumor-immune interactions within the microenvironment is crucial for advancing cancer immunotherapy. Here, we developed a novel approach integrating highly multiplexed imaging, laser microdissection, and deep visual proteomics (DVP) to spatially profile the proteomes of 21 distinct cell populations in human colorectal and tonsil cancers with high sensitivity. We selected colorectal tumor as an example of a cold tumor, uncovering an immunosuppressive macrophage barrier impeding T cell infiltration and regionally altering lymphocyte proteomes. Spatial proteomic analysis revealed distinct functional states of T cells in different tumor compartments. In tonsil cancer - a hot tumor, we identified significant heterogeneity of cell proteomes influenced by proximity to cytotoxic T cell subtypes. Tumor-infiltrating T cells exhibited metabolic adaptations and enhanced stress resilience, enabling migration into hypoxic regions. Our spatially-resolved, highly multiplexed strategy deciphers the complex cellular interplay within the tumor microenvironment, with implications for identifying new immunotherapy targets and signatures. Highlights Novel approach integrates multiplexed imaging and deep proteomics to profile the tumor microenvironment Identified 21 distinct cell populations and thousands of proteins from single cell types Macrophage barrier impedes T cell tumor infiltration and T cells adapt to hypoxia Spatial insights may guide new immunotherapy targets and personalized oncology