Agglutination Group

Group agglutination (from the Latin agglutinatio - gluing) is a specific A. class. or bacteria, occurring under the influence of agglutinins directed to group (common) antigens (for example, group antigens of erythrocytes). Unlike type-specific A., group A. is not caused by the presence of antibodies to a specific antigen in the serum. It occurs only in the presence of serum containing group agglutinins and antigens common to all representatives of this group. Group A. is caused by sera with group agglutinins directed to the group antigen of erythrocytes. In group A., erythrocytes form aggregates that have the shape of an “umbrella,” “shell,” or “colloidal rose” and consist of many erythrocytes fused together, i.e., erythrocyte aggregates. Group A. can be positive (if the red blood cells stick together) and negative (if they do not stick together). Group agglutination can only be detected when using serum containing group agglutinins. Common antigens are called group antigens, i.e. those that are found in representatives of different blood groups, for example, blood group A antigens and group O antigens.

Group-type agglutination, also group adhesion of microbes or blastospores, is a specific reaction of bacteria or other cells that occurs under the influence of antibodies directed at group (group-specific), often common antigens. The appearance of such forms of aggregation is possible only under several conditions - you must first have antibodies in the blood serum with various specific epitopes from the common antigenic block, i.e., group-specific. Group (paired, twin) agglutination is the result of the interaction of 2 or more plasmodia of the same or different antigenic types (for example, Plasmodium falciparum and Plasmodius vivax), the action of which is directed against the surface antigens of the opponent. A “group reaction” can also occur in known pathogens, for example, during the pathogenesis of typhoid fever, a thermostable thermohemolysin (Ag-complex), represented by tetramers, is formed. The purpose of aggregation is to stop the malarial plasmodium in the form of a pale spirochete. The group agglutinol reaction proceeds hundreds of times faster. A large percentage of aggregates provokes the death of the parasite, the release of a soluble antigen that prevents the arrival of