Method for detection and isolation of cholesteryl ester-containing "foam" cells using flow cytometry

Area of Science:

• Cardiovascular Biology
• Cellular Metabolism
• Atherosclerosis Research

Background:

• Cholesteryl ester accumulation in vascular cells defines atherosclerotic lesions.
• Monitoring this cellular event is crucial for understanding atherosclerosis development.

Purpose of the Study:

• To develop a method for detecting cholesteryl ester-containing cells (foam cells) in aortic cell suspensions.
• To enable specific detection of cholesteryl ester in the context of atherosclerosis.

Main Methods:

• Developed a method using the fluorescent dye filipin for selective cholesteryl ester staining.
• Employed ethanol extraction to remove unesterified cholesterol, preventing interference.
• Utilized enzymatic hydrolysis to make esterified cholesterol available for detection.
• Analyzed stained cell suspensions via flow cytometry for detection and sorting of foam cells.

Main Results:

• Successfully detected and quantified cholesteryl ester-containing cells in both normal and atherosclerotic swine aortas.
• Observed a higher prevalence of foam cells in atherosclerotic aortas.
• Correlated higher fluorescence levels with increased cholesteryl ester inclusions within cells.

Conclusions:

• Flow cytometry provides a viable method for detecting cholesteryl ester-containing cells.
• This technique is valuable for studying cellular cholesterol metabolism.
• The method is applicable to specific research on cellular cholesterol accumulation in atherosclerotic vessels.