Side chain theory
Paul Ehrlich's side chain theory is a theory about antibody formation and a forerunner of today's selection theories of immune defense . It was based on the assumption that every cell has protein-containing substances and a series of side chains or receptors that absorb nutrients and certain toxic substances. These side chains of the cells ( blood cells ) match the chemical groups of the penetrated toxins , which are now multiplied and released into the blood, where they act as antitoxins. The foreign bodies bind according to the lock and key principle . Ehrlich received the Nobel Prize in Medicine for this theory in 1908 .
The emergence of the theory
Paul Ehrlich examined the specific immune defense of the body and assumed that foreign substances or infectious agents or their toxins dock on certain cells of the body. In the course of his research he developed the theory that these exogenous substances have chain-like molecular structures ( antigens ) that match the similar "side chains" of cells "such as keys and locks" and are thus bound to them. He suspected that these specific side chains, which became unusable due to the permanent connection with the antigen, would be produced anew by the cell as a replacement in an excessively excessive reaction and released into the blood as free "antibodies" ( antibodies ) and thus the humoral immunity guaranteed. However, Ehrlich and other researchers later discovered that several antibodies are often required to neutralize toxins or infectious agents and that it is their interaction that is responsible for immunity. Ehrlich then dealt more intensively with the receptors and found out, contrary to his original assumption that all body cells could produce antibodies, that this only applies to the B lymphocytes . Ehrlich recognized that different structures are present on the respective antigen, which he subdivided into haptophore and toxophore groups, with the former causing the bonds and the latter being responsible for the pathogenicity . He went on to discover that serum complement factors attract the phagocytic cells of the immune system, the scavenger cells ( macrophages ). This laid the foundations for modern immunology .
Ehrlich received the Nobel Prize for this knowledge in 1908 together with Ilya Ilyich Metschnikow , the discoverer of phagocytosis . Antibody-like receptors were later found on other immune cells as well. Paul Ehrlich's basic assumption of receptor-controlled immune reactions is still valid today, despite some improvements.
literature
- Arthur M. Silverstein: Paul Ehrlich's Receptor Immunology. The Magnificent Obsession . Academic Press, San Diego 2002, ISBN 978-0126437652 .