Haptens

HAPTENS, a term introduced by Landsteiner for the incomplete antigens discovered by him (see). Antigens in general are characterized by two properties: 1) to cause the appearance of antibodies in the blood serum of animals into which they are introduced parenterally, and 2) to give various immunity reactions with these antibodies. Meanwhile, in studying the so-called Forssman antigen, Landsteiner found that while the native antigen causes the appearance of hemolysins, the alcoholic extract made from it does not lead to the formation of hemolysins, although it is capable of reacting with them. This extract, containing lipoids, thus possesses only one property of a complete antigen—reaction with the antibody—but lacks the other—ability to cause antibody formation. Subsequently, it turned out that such "incomplete antigens"—haptens—are widely distributed. Bacterial haptens acquired particular importance. Zinsser extracted H. from various bacteria, giving them the name "residual antigens." The most important research in this regard was done by Avery and his colleagues regarding H. of pneumococci. These researchers isolated H. from the bodies of pneumococci of various types and showed that these H. are different in various types and are complex carbohydrates. Then it was found that the presence of H. is reflected in the appearance of colonies and the toxicity of bacteria. The content of H. is characteristic of smooth colonies (as opposed to rough) and virulent bacteria. Gamaleya found in the culture of blue pus bacteria a carbohydrate that increases the pathogenic action of microbes.

Pneumokokkentypen Haptene? Zeitschrift f. Hygiene u. Infektionskrankheiten, B. CVIII, 1927. H. Gamaleya.