June 4th, 2026
Once past the early stages, an atherosclerotic plaque in a blood vessel wall grows by drawing in and killing macrophage cells of the innate immune system. These cells are responsible for clearing up damage and excess lipids in blood vessel walls, but the plaque environment has become too toxic for their long term survival. Some macrophages work to resolve the issue, but most are overwhelmed, become inflammatory and eventually die. Researchers are very interested in finding possible ways to alter macrophage behavior to favor greater efforts to repair the plaque environment. One class of possible approaches involves trying to force adoption of particular set of behaviors via altering regulatory systems in the cell to override the normal reaction to the plaque environment. New options on this front arise from efforts to obtain a better understanding of which factors are in fact determining cell behavior.
Over many years, so-called macrophages - scavenger cells of the immune system - accumulate in the vessel wall. They take up fat, store it, and eventually die. What remains are cell debris and deposited fats, from which cholesterol crystals can form. These crystals destabilize plaques, promote blood clot formation, and thereby increase the risk of an acute vascular blockage. Researchers have now taken a closer look at the role played by different macrophages in atherosclerotic plaques. Not only lipid-laden macrophages but also lipid-free macrophages play a decisive role in shaping the disease process.
