Spectral, Semi-Spectral, and Bandwidth Flow Cytometric Implementation of Multiplex Cytokine Bead Assays

Area of Science:

• Biotechnology
• Analytical Chemistry
• Immunology

Background:

• Multiplex cytokine bead assays (MCBA) traditionally use conventional flow cytometers.
• Conventional flow cytometry faces challenges with unmixing distortions when analyzing full-spectrum data.
• Existing manufacturer setup beads are unsuitable for full-spectrum flow cytometry MCBA.

Purpose of the Study:

• To implement and characterize the first full-spectrum flow cytometry for MCBA.
• To develop and validate in-house reference fluorophore controls (RFCs) for spectral unmixing.
• To compare the performance of spectral, semi-spectral, and bandwidth modes in MCBA.

Main Methods:

• Developed in-house RFCs using streptavidin-conjugated carboxylated polystyrene beads titrated with PE-biotin.
• Utilized full-spectrum flow cytometry for spectral data acquisition and analysis.
• Compared spectral, semi-spectral, and bandwidth modes using established and in-house RFCs.

Main Results:

• In-house conjugated PE beads demonstrated autofluorescence profiles matching kit beads.
• Proper use of PE and APC RFCs enabled accurate spectral unmixing without distortions.
• Spectral mode exhibited superior precision and resolution compared to semi-spectral and bandwidth modes.

Conclusions:

• Full-spectrum flow cytometry, with optimized RFCs, enables accurate and distortion-free MCBA.
• The spectral mode offers significant advantages in precision and resolution for MCBA.
• Full-spectrum flow cytometry expands possibilities for complex multi-analyte bead assays.