Autoimmunization

AUTOIMMUNIZATION (Greek autos-self), immunization of the organism by products that are formed within it or, generally, that are present in it itself. The difference between A. and simple immunization, however, is only relative, not essential. One speaks of A. when, for example, there is some chronic infectious focus in the organism and bacterial products, absorbed from there, immunize the organism, or if certain microorganisms vegetate permenantly or for a certain time somewhere on the mucous membranes (mouth, intestine), even not causing any disease, but to which symbiosis the organism reacts by the formation of antibodies or by an increase in tissue resistance. But just as in ordinary immunization, the antigen that gives the impulse to the immunizing effect is here ultimately of exogenous origin, and the difference in both cases lies only in the duration of the contact of the immunizing agent with the organism. Conditions for the proper course of the A. process are not always favorable: if the infectious focus is tightly encapsulated, the absorption of immunizing substances is hindered, but, on the other hand, it is bad if this absorption occurs in larger sizes than necessary: the suppressed organism does not then produce protective substances. Therefore, in a number of cases, artificial intervention in the form of the introduction under the skin into healthy places of the body of exactly controlled quantities of immunizing substances is indicated. The so-called autoserotherapy proposed by Gilbert (which consists in the fact that in tightly absorbing infectious pleurisies the pleura is punctured and a small amount of exudate containing bacterial products is withdrawn and injected under the skin of the same patient) is one of the kinds of such intervention. The A. process plays a large role, among other things, in tuberculosis. In the same way, some so-called normal antibodies, i.e., formed not as a result of a transferred infection (for example, against the intestinal bacillus), possibly have an autoimmunizing origin. As regards diphtheritic antitoxin, found in 83–85% of cases in the blood of adults who have not had diphtheria, opinions on the question of its origin are diverse: Wassermann and Zingher explain this phenomenon as precisely unnoticed autoimmunization; Greer and Kassowitz speak of changes connected with age — of "serological maturation."