In a story about good and bad glucocorticoids we discussed exactly how leukocytes get out of the blood into the surrounding tissues. And they need to get out. Because our diseases very often begin and end somewhere in the periphery. Maybe it's pneumonia, or maybe just a splinter in the finger.
That is, throughout the body, we have immunity cells stuck, which are the first to meet infection and raise the alarm. Then they call out reinforcements from the blood.
Leukocytes constantly patrol our body with blood flow. They follow the signals like kites. If some suspicious chemical compounds seep from the wall of a blood vessel, then leukocytes immediately dive from the heavens and flop on this wall.
It is clear that this is happening inside a blood vessel through which blood flows rapidly. So leukocytes do not just land, but roll along the vessel wall for some time. Like a tumbleweed. Have you seen these bushes rolling along the road? This is how leukocytes roll along the wall of a blood vessel.
Then the leukocytes manage to catch on and slow down. They already know for sure that something bad is going on behind the wall of the vessel, and they need to go there.
Then the leukocytes begin to squeeze between the cells lining the wall of the vessel, and slowly crawl out. It used to be thought that this is how the leukocytes turn everything. But then it turned out that they know how to go ahead.
It was literally photographed under a microscope. They say that in about 30% of cases, the leukocyte does not crawl and does not look for a gap for itself to squeeze into it. No. He grows his leg and starts kicking a cage that is in his way.
Remember school biology? There was about an amoeba with a pseudopod, with which the amoeba walks and pokes everything. So our native leukocyte kicks the cell wall with the same pseudopod and pushes a hole in it. Then he himself falls into this pit, and the cage covers him from above.
Well, it's as if someone was digging a deep well, and then the earth crumbled on it, and he would have to dig further to get out. So the leukocyte is punching its way out through the vessel wall.
And nobody kicked you from the inside?
