Isoantigens And Isoantibodies

ISOANTIGENS AND ISOANTIBODIES, include isoantibodies and isoantigens. Isoantibodies are serum antibodies that act on the tissues and organs of animals of the same species as the animal producing the antibodies, but do not act on the animal's own tissues and organs. From isoantibodies are known: isoagglutinins, isoprecipitins, isohemolysins, isosensibilins, etc. Isoantigens are the tissues and organs of an animal that, when used for immunization, cause the formation of isoantibodies for that animal species. The concept of isoantigens and isoantibodies was first introduced by Ehrlich and Morgenroth in 1900. These authors showed the formation of isohemolysins in goats under the influence of the injection of goat blood into them. Landsteiner in 1901 established the physiological presence of isoantibodies (isoagglutinins, see Hemagglutination) in human blood and proved the existence of individual isoantigens (erythrocytes) in the blood and the possibility of their serological differentiation into groups. The group properties of human isoantigens are inherent not only in the blood. They are found in milk (Hirszfeld) and in other body fluids and even in organs (Krichevsky and Schwarzman; 1927). For animal tissues, no strict regularity in their division into groups has yet been proven. The group characteristics of isoantigens are inherited and are constant, for which reason the doctrine of blood groupings has acquired significance in the study of racial and constitutional characteristics, and in medicine - in blood transfusion, transplantation, and in forensic medical examination.