The immune system is there to knock out intruding pathogens such as bacteria and viruses, as well as to remove malignant modified cells. It comprises innate non-specific and acquired specific defence mechanisms. The specific immune reaction distinguishes between self and foreign, activating the non-specific components of the immune system that spread information about the pathogen quickly and efficiently and then destroy the dangerous intruder.

Specific Immunity

The specific defence system is responsible for the distinction between foreign and self in the human body. It comprises, among others, lymphocytes and the immunoglobulins (Ig), also known as antibodies, which are distinguished according to their tasks (IgA, IgD, IgE, IgG, IgM). From the time of birth, the immune system begins to learn what structures is part of self. During this early phase, all substances it comes into contact with are registered as part of self. Substances that are introduced later are automatically registered as foreign. These foreign substances are called antigens.

Antibodies are Y shaped, the bottom part of the Y containing the negative shape of a structure found on the surface of the antigen. In a lock-and-key interaction, the antibody binds to the antigen to mark it as foreign, triggering further reactions within the body, which will result in disabling the antigen.

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Article Index
1 The Immune System
2 Rapid Spread of Information