Relationship between light scattering in flow cytometry and changes in shape, volume, and actin polymerization in...

Area of Science:

• Immunology
• Cell Biology
• Biophysics

Background:

• Flow cytometry is widely used to analyze cellular properties.
• Polymorphonuclear leukocytes (PMNs) undergo significant shape changes upon stimulation.
• Assessing PMN activation often relies on changes in cell scatter properties.

Purpose of the Study:

• To evaluate the reliability of forward and right angle scatter in flow cytometry for measuring PMN shape, volume, and actin polymerization.
• To determine if distinct PMN shape changes can be identified using different cytometers.

Main Methods:

• Comparison of Epics Profile II and FACScan cytometers.
• Analysis of forward and right angle scatter changes in stimulated human PMNs.
• Assessment of correlation between scatter properties and PMN morphology/actin polymerization.

Main Results:

• PMN stimulation altered scatter plots on FACScan, but not Epics Profile II.
• FACScan could detect the occurrence of PMN shape change, but not its type.
• Neither cytometer reliably indicated PMN volume or actin polymerization changes.
• Distinguishing between spherical, polarized, or nonpolar PMN shapes was not possible with either instrument.

Conclusions:

• Forward and right angle scatter are not consistently reliable indicators of PMN activation status, particularly for specific shape changes or intracellular events like actin polymerization.
• The FACScan offers limited utility in detecting PMN shape alterations compared to the Epics Profile II.
• Further development of flow cytometry methods is needed for detailed analysis of PMN activation states.