What is mass cytometry?

Mass cytometry, also known as CyTOF (Cytometry by Time-Of-Flight), is a technique used for single-cell analysis. Instead of using fluorescent labels like traditional flow cytometry, it uses heavy metal isotopes conjugated to antibodies. These metal-tagged antibodies bind to specific cellular proteins. The cells are then atomized and passed through a mass spectrometer, which measures the mass-to-charge ratio of each metal isotope, allowing for the quantification of dozens of cellular markers simultaneously. It's commonly used in immunology, cancer research, and drug discovery to deeply profile cell populations and identify rare cell types.