Hex-MASP for mapping the whole-tissue spatial proteome and the intrabrain distribution of monoclonal antibodies

Abstract

Significance Spatial proteomics at the whole-tissue level is essential for deciphering spatially organized biological regulation yet remains out of reach for most existing methods. Here we introduce hex-MASP (micro-scaffold assisted spatial proteomics), a next-generation spatial proteomics platform that uses a 3D-printed hexagonal micro-scaffold to enable high-resolution, reproducible, and quantitative mapping of thousands of proteins across entire tissues. Applied to mouse brain treated with monoclonal antibody drugs, hex-MASP quantified over 6,000 proteins with extensive depth and high accuracy and resolved the whole-brain distribution of therapeutic antibodies. These data revealed previously unrecognized mechanisms of antibody penetration and region-specific regulation, providing a powerful resource for understanding biotherapeutic tissue penetration and spatially organized biological processes at the whole-tissue scale.