[Functional disorders of the immune system].

In common with other organ systems in the body the immune system demonstrates functional disturbances which may lead to numerous immunological disorders with grave consequences for the health of the patient. Whenever the complex network of regulation and counter-regulation mechanisms within the defence system is impaired, by hereditary or acquired defects, immunological defect syndromes occur. One of the disorders that has been the object of intensive discussion in this context over the past few years is the acquired immune deficiency syndrome AIDS, a dangerous viral infection that mostly affects the T4 cells, whose helper and inductor function is absolutely essential for successful immunological defence. Furthermore, functional impairment of the antibody-producing plasma cells leads to the heterogeneous group of gammopathies which are characterized by an uncontrolled and excessive proliferation of structurally uniform antibody molecules in the blood. Overreactions of the immune system which wrongly attack endogenous tissue are accredited with causing the so-called auto-immune diseases. The clinical pictures within this group are exceptionally varied, and depend both on the self-antigen that the attack is aimed at as well as the erroneously triggered effector function that is affected. Whenever the immune system reacts disproportionately strongly against otherwise harmless foreign antigens, allergic clinical picture emerge.