Advances in Mass Spectrometry-Based Single Cell Analysis

SIMPLE SUMMARY: Cell-to-cell variation exists within a population of the same cell type due to stochastic gene and protein expression and environmental factors. Studying such cellular heterogeneity is the key to understanding the underlying mechanisms of fundamental biology and complex diseases, highly demanding developments in advanced technologies for molecular profiling at the single-cell level. The growth of single-cell RNA sequencing techniques has significantly contributed to this field. Moreover, the development of mass spectrometry (MS)-based methods for analyzing proteins and metabolites in a single cell is rapidly progressing. This review aims to present recent advances in MS-based single-cell analysis and their applications in biology and medicine. ABSTRACT: Technological developments and improvements in single-cell isolation and analytical platforms allow for advanced molecular profiling at the single-cell level, which reveals cell-to-cell variation within the admixture cells in complex biological or clinical systems. This helps to understand the cellular heterogeneity of normal or diseased tissues and organs. However, most studies focused on the analysis of nucleic acids (e.g., DNA and RNA) and mass spectrometry (MS)-based analysis for proteins and metabolites of a single cell lagged until recently. Undoubtedly, MS-based single-cell analysis will provide a deeper insight into cellular mechanisms related to health and disease. This review summarizes recent advances in MS-based single-cell analysis methods and their applications in biology and medicine.