The immune system, which appeared in the process of evolution, provides the body with a high level of protection, and its disorders are the cause of a number of diseases.
Recently, the development and study of specific agents that stimulate or suppress immune responses are of great importance. It became obvious that the positive effect of many drugs is explained by an increase in the general resistance of the body, its nonspecific immunity, as well as the activation of specific immune responses. Immunomodulators, immunostimulants, immunosuppressants are substances that modify the immune response and affect immunocompetent cells. The sources of their production are very diverse: microorganisms, plants, tissues and organs of animals, chemical synthesis.
Immunostimulants and immunosuppressants can be antigens and non-antigens, specifically or nonspecifically alter the functioning of the entire system or its individual links (immunocompetent cells and subcellular formations).