The wonderful human immune system - macrophages
The immune system of man
Our immune system is a wonderful, highly complex system. Since time immemorial, it has protected us from pathogens from the environment. It has the ability to constantly "learn" and develop further. In medical school we learned about important processes of the immune system. However, recent years have brought new breakthrough findings. In 2011, the Nobel Prize was awarded in connection with the discovery of the fascinating "Toll-like" receptor of macrophages. More discoveries are certainly yet to come. Activation of the T-lymphocyteThe macrophages They are the "guardians of our immune system." They are at the front line in the mucous membranes, where they form the first line of defense to counter pathogens. They are also called "giant food cells". With their "big appetite" for anything that could harm us, they "eat" pathogens such as bacteria, fungi and viruses. (See Fig.) If they recognize the enemy, they can flow around it and ingest it (phagocytosis). Special fighting substances inside the macrophages (certain enzymes) then destroy the trapped viruses or bacteria. But what happens if the macrophages cannot completely eliminate the "enemy"? The pathogen then attacks our normal cells. These infected endogenous cells can no longer be saved. ation of the T-lymphocyteThe macrophages, however, can recognize that they are infected and eliminate these harmful body cells, together with the pathogens they contain. The multiplication of the pathogens is thus effectively counteracted. Macrophages are developmentally one of the oldest parts of the immune system. Like good generals, they can not only fight but also send commands to their defensive army. Macrophages produce "inflammatory mediators" that can activate and recruit other cells of the immune system. Once the enemies are defeated, macrophages present harmless components of the attacking bacteria and viruses on their cell surface to communicate further information about the "enemy" to other immune cells. We have learned that macrophages carry a kind of "intelligence" within them. They can recognize pathogens. Macrophages eliminate pathogens or body cells that have already been attacked. They send information to our other immune defense cells.
