Pathogens are constantly entering our body. Almost all of them are eliminated by our immune system without us noticing. This is where, for example, the skin cells come into play, which represent an external barrier against intruders and constitute the first protective barrier. With a surface area of almost two square meters, it constitutes an important and strong barrier in combination with the mucous membranes of the mouth, throat, nose and gastrointestinal tract. With an incredible eight meters in length and 500 square meters of surface area, our intestine is the largest immune organ in the body and as large as a soccer field!
Patrolling scavenger cells, so-called macrophages, recognize the intruders on their surface, devour them and decompose them inside. In addition, they use messenger substances to summon further defence cells, like the so-called granulocytes. These destroy the remaining pathogens with the help of substances.