What role do foam cells play in atherosclerosis?

Foam cells are a significant component in the development of atherosclerosis, as they directly contribute to plaque buildup. These cells are formed when macrophages, a type of white blood cell, ingest oxidized low-density lipoproteins (LDL) in the arterial wall. When the macrophages take up excessive amounts of cholesterol-rich particles, they become engorged and take on a foamy appearance, hence the name "foam cells."

The accumulation of foam cells leads to the formation of fatty streaks, which are the early stages of atherosclerotic plaque. As more foam cells accumulate, they contribute to the growth of these plaques, resulting in narrowing and hardening of the arteries. This buildup can subsequently lead to cardiovascular complications, including heart attacks and strokes, when blood flow is obstructed.

In contrast, while foam cells can influence processes like lipid oxidation and inflammation, their primary role is as a building block in plaque formation in the arterial walls. Their presence indicates the progression of atherosclerosis and the risk of cardiovascular disease.