The immune system can help us resist pathogens, which is its defense function. However, if the immune system is too weak or too strong, it may lead to autoimmune diseases, which in turn will have a pathogenic effect.
The most effective weapon against pathogen invasion, it can find and remove foreign bodies, foreign pathogenic microorganisms and other factors that cause internal environment fluctuations. However, its hyperfunction will cause harm to its own organs or tissues.
Through autoimmune tolerance and immune regulation, the internal environment of the immune system remains stable. Repairing immune cells can repair damaged organs and tissues and restore their original functions. A healthy immune system is irreplaceable, but it may still fail because of continuous intake of unhealthy food.
Extended data
Normal human body fluids, such as blood, tissue fluid and secretion fluid, contain many substances that can kill or inhibit pathogens. There are mainly complement, lysozyme, defensin, B- lysin, phagocytin, histone, normal opsonin and so on. The direct killing effect of these substances on pathogens is not as strong as that of phagocytes, and they often only cooperate with other antibacterial factors.
For example, complement has only a weak bacteriostatic effect on Vibrio cholerae, but if complement is added to the complex of Vibrio cholerae and its specific antibody, the bacteriolytic reaction of Vibrio cholerae will soon occur.
When pathogenic microorganisms such as germs and viruses enter the human body, macrophages in the immune system first attack and engulf them in the "stomach", and then break them into pieces through the action of enzymes. These microbial fragments appear on the surface of macrophages and become antigens, indicating that they have swallowed the invading germs and let T cells in the immune system know.
T cells and microbial fragments on the surface of macrophages, or microbial antigens, react immediately after meeting, just like the original locks and keys. At this time, macrophages will produce a lymphatic factor substance, and its biggest function is to activate T cells.
Once T cells "wake up", they immediately send out an "alarm" to the whole immune system and report the news of "enemy" invasion. At this time, the immune system will dispatch a killer T lymphocyte, which will emit special B lymphocytes, and finally produce specific antibodies through B lymphocytes.
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