Alternative methods of viability determination in single cell mass cytometry

Area of Science:

• Cell Biology
• Immunology
• Biochemistry

Background:

• Accurate identification of viable cells is crucial for understanding cellular processes like metabolism, cell cycle, and signaling pathways.
• Cisplatin is a common viability stain in mass cytometry but can interfere with antibody staining due to its platinum-based nature.
• This interference complicates simultaneous viability and antibody staining in high-parameter analyses.

Purpose of the Study:

• To identify alternative viability stains for mass cytometry that do not interfere with platinum-based antibody staining.
• To evaluate protein antigen markers as a method for discriminating live and dead cells without a separate viability stain.
• To offer improved strategies for viability assessment in mass cytometry, especially when using platinum isotopes for antibody labeling.

Main Methods:

• Tested alternative metal salts (hafnium, niobium, and zirconium chlorides) as viability stains in mass cytometry.
• Compared the performance of these alternative stains to cisplatin in terms of live/dead cell fractions.
• Validated the use of protein antigen viability markers (pRb, Ki-67, Histone H1, cleaved PARP, GAPDH) for discriminating cell viability.

Main Results:

• Hafnium, niobium, and zirconium chlorides effectively substitute for cisplatin as viability stains, yielding comparable live/dead cell populations.
• These alternative stains identify the same dead cells as cisplatin in parallel high-parameter analyses.
• As few as two protein antigen markers can accurately identify live and dead cell populations in fixed samples, even without a dedicated viability stain.

Conclusions:

• Alternative metal salts offer viable substitutes for cisplatin in mass cytometry viability staining.
• Protein antigen markers provide a robust alternative to chemical viability stains, simplifying experimental workflows.
• These methods enhance the utility of mass cytometry by enabling platinum isotopes for antibody staining and improving live/dead cell discrimination.