uni'wissen 02-2015_ENG

always a troop of microglia on hand to clean up in the brain of a healthy person. Marco Prinz is medical director of the Institute for Neuropathology at the Freiburg University Medical Center and has been studying microglia for many years. He first became fascinated with the brain in the anatomy seminars he took while studying medicine at the Charité teaching hospital in Berlin, where he wrote his dissertation on nerve cells in the brain at the Institute of Anatomy. He then accepted a position at the Institute of Neuro- pathology of the University of Zurich, Switzerland. It was there that he began focusing more closely on microglia. “They have not been known for very long, and we are only learning little by little what function they have in the brain.” The Greek word “glia” literally means “glue.” The brain gardeners owe their name to the doctor Rudolf Virchow, who saw them as a kind of sup- port substance for nerve cells that holds them in place or glues them together. Only gradually was it discovered that glial cells in general and microglia “It’s a bit like cleaning up after a party.” in particular also serve other, entirely different purposes. Microglia are diligent gardeners. They take their job seriously and spend all of their time looking after the nerve cells. They are constantly scavenging through the brain with their little arms, always on the lookout for undesirable changes and removing them immediately. The tiny house- keepers are even mobile: if a part of the brain gets injured, the surrounding microglia travel to the spot and repair it. “It’s a bit like cleaning up after a party,” explains Prinz. “The microglia try to restore the brain to its original state, in which it works best, as quickly as possible.” Approximately 10 to 15 percent of all brain cells are microglia. That might not seem like much, but their work is essential. This becomes particularly evident when they are damaged: “When microglia can no longer fulfill their duties and the nerve trees grow uncontrollably in the brain or the gardeners chop off healthy and useful branches instead of sick ones, that of course has consequences for the brain,” says Prinz. There is an increasing amount of evidence that microglia can not only potentially cause inflammations of the brain and its protective membranes, but that they can even play an important role in diseases Diligent workers: Much like gardeners tend their trees and repair damage to them, glial cells look after the nerve cells in the brain. Illustration: Svenja Kirsch 13uni wissen 02 2015 13 13uni wissen 02201513

Seitenübersicht