Calling out the cell undertakers
By John Travis
Millions of cells die naturally each day in a person. Scientists have now discovered that these dying cells send out a chemical signal to attract other cells that specialize in disposing of cellular corpses.
Over the past few years, biologists have begun to understand how macrophages and other cells recognize dying cells. For example, a cell about to die sprouts what scientists refer to as eat-me signals, which tell a macrophage to consume the cell before it falls apart and triggers inflammation (SN: 9/28/02, p. 202: Get Rid of the Bodies).