Single cell analysis of human tissues and solid tumors with mass cytometry

Area of Science:

• Biomedical Engineering
• Immunology
• Oncology

Background:

• Mass cytometry offers comprehensive cellular phenotyping of human tissues and tumors.
• Established protocols for tissue disaggregation and fluorescence cytometry may not be optimal for mass cytometry.
• Maintaining cancer and stromal cell diversity during sample preparation is critical.

Purpose of the Study:

• To systematically compare tissue preparation techniques for mass cytometry.
• To identify optimal enzyme combinations and dissociation times for preserving cell viability and diversity.
• To establish standard procedures for preparing single-cell suspensions from human tissues for mass cytometry.

Main Methods:

• Systematic comparison of tissue preparation techniques for gliomas, melanomas, xenografts, and tonsil tissue.
• Assessment of various enzymes including DNase, HyQTase, TrypLE, and collagenases (Col II, IV, V, XI).
• Utilized fluorescence and mass cytometry to evaluate cell subset abundance after different enzymatic treatments.

Main Results:

• Mechanical disaggregation combined with 1-hour enzymatic dissociation (Col II, IV, V, or XI plus DNase) yielded the highest viable cell count.
• Extended dissociation times increased cell death and disproportionately reduced cell subset representation.
• Mass and fluorescence cytometry showed comparable frequencies for cancer cells, leukocytes, and endothelial cells in glioma and tonsil samples.

Conclusions:

• Established standard procedures for preparing viable single-cell suspensions from human tissues.
• Preservation of cellular diversity in human tissue microenvironments is achievable.
• Optimized protocols enhance the utility of mass cytometry in cancer research and diagnostics.