Cellular function is largely governed by the complex, heterogeneous and dynamic proteome, influencing key processes such as tissue localization, cell-cycle progression, response to external stimuli, functional polarization, differentiation, disease states or therapeutic responses. While microscopy and sequencing-based approaches have provided extensive insights into cell-type diversity and subcellular organization, comprehensive characterization of the global proteome and its post-translational modifications at single-cell resolution remains challenging. Single-Cell Proteomics (SCP) enables proteome-wide measurements at single-cell resolution through sensitive mass spectrometry instrumentation and dedicated workflows. The field has seen rapid growth, with multiple dedicated international conferences and increasing representation at major scientific meetings, including HUPO and ASMS.

Continued developments in SCP will be critical for refining our understanding of cellular function and heterogeneity, ultimately advancing applications in biomedical research and precision medicine.