CyTOF combines the single cell high-speed analysis associated with flow cytometry with the ability to resolve up to 100 different metal probes with minimal signal overlap associated with atomic mass spectrometry.
In contrast to flow cytometry, antibodies coupled to stable transition element isotopes are used to stain cellular epitopes.
CyTOF technology currently allows the simultaneous measurement of up to forty cell surface and intracellular antigens at the single cell level. Coupled with powerful high dimensional analysis software this technology allows the comprehensive phenotyping of heterogeneous cell populations combined with functional profiling of signaling and cytokine pathways active within individual cells.
How mass cytometry works
The workflow for a CyTOF experiment is very similar to flow cytometry. However, in contrast to using fluorochrome-conjugated antibodies, cells are stained with metal-conjugated antibodies directed against cell surface and intracellular proteins.
Cells are introduced individually into an Inductively Coupled Plasma (ICP) by droplet nebulization. Here cells are atomized to release the metal ions, with ions derived from each stained cell maintained in discrete clouds.
Metal ions of interest are resolved by mass in the time-of-flight (TOF) chamber
The time-resolved detector produces a mass spectrum that represents the identity and quantity of each isotopic metal tag on a per-cell basis.
Data is generated in .fcs format and can be analyzed using standard flow cytometry data analysis programs or newer data analysis software for high-dimensional data such as Cytobank, Spade, and others.