Quantitative Single-Cell Multielemental Analysis Using Metal-Loaded Microparticles: toward a Universal Quantification...

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Cell Biology

Background:

• Lanthanide-tagged antibodies allow multiplexed biomarker monitoring in single cells using mass cytometry.
• Accurate quantification of these tags is crucial for reliable single-cell analysis.

Purpose of the Study:

• To develop and validate a quantitative workflow for multielement determination in single-cell events using mass cytometry.
• To establish a generalizable method for quantifying lanthanide tags on cells.

Main Methods:

• Utilized multielement barcoded polystyrene beads for online calibration in mass cytometry.
• Employed time-of-flight mass spectrometry (TOF-MS) to discriminate cell and bead events.
• Developed a polynomial model for multielemental analysis and quantification of untagged elements.

Main Results:

• Demonstrated accurate quantification of Lutetium (Lu) in lymphocytic leukemia cells using a Lu-tagged antibody.
• Successfully performed multielemental analysis in ovarian cancer cells using Neodymium (Nd)-tagged antibodies and an Iridium (Ir) intercalator.
• Achieved excellent agreement with external calibrations, validating the workflow's quantitative accuracy.

Conclusions:

• The developed workflow provides a robust method for quantitative single-cell analysis using mass cytometry.
• This approach enhances the capabilities of high-dimensional single-cell mass spectrometry for biomarker discovery and diagnostics.
• The method is broadly applicable to various lanthanides and adaptable for single-cell ICP-MS with TOF analyzers.