Imaging mass cytometry - elemental immunohistochemistry for multiparametric imaging and quantitation

Abstract

Abstract Pathology assessment of tissue sections provides prognostic evaluation and helps select optimum treatment regimens. Digital pathology has made significant strides in the analysis of several markers. There is a growing understanding of cell heterogeneity within tumor tissue, role of microenvironment, and the impact of immune cells on cancer development. Sophisticated tools are needed to provide quantitative information for a large number of biomarkers, low-abundance small molecules and chemotherapeutic drugs, while retaining spatial resolution of cells and tissue architecture. Imaging mass cytometry (IMC) is a novel technology that can simultaneously detect and quantitatively measure more than 50 metal-containing reagents in tissue sections at 1 μm resolution. IMC combines laser ablation with the Helios CyTOF®. We will describe in detail technology, workflow, multiplexing protocols, image analysis and show representative data for human and mouse sections. We will demonstrate the use of metal-containing histological stains for tissue architecture, and endogenous element identification [iodine, platinum]. Combined detection of protein targets and transcripts within cells will be presented. Validation will be demonstrated on sequential tissue sections prepared by conventional immunohistochemistry. Precision medicine is based on access to high-density data (proteomics and genomics) which provides accurate diagnosis and information on the best therapeutic approach. IMC is a highly multiparametric, quantitative method for phenotypic, signaling pathway, and cell state protein identification together with spatial information within tissue sections.