The immune system can rightly be called the foundation of the vital activity of the body. Without exaggeration, all diseases are somehow associated with breakdowns of immunity. This connection can be direct (a violation in the immune system leads to the development of the disease) or reverse (the disease makes adjustments to the work of immunity). The most obvious examples are infectious and autoimmune diseases, allergies, cancers, etc.
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 The immune system is a very complex, finely tuned mechanism in which everything is interconnected. No smart person will say: "I know everything about immunity," because world science is still far from this statement. 

To begin with, immunity is divided into: 

1.Nonspecific (it is also congenital) and
2.Specific (adaptive). 
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 Non-specific immunity protects us from everything that seems suspicious and dangerous to it. The first line of defense is represented by natural barriers. This includes t...