[Antibody activity of monoclonal immunoglobulins]

Monoclonal immunoglobulins present a normal structure and have an antibody activity. This activity may be directed against exo-antigens especially bacterial, but more frequently against auto-antigens. It may then be symptomatic and therefore explain unusual clinical or biological manifestations in the course of monoclonal dysglobulinemias; but, most of the time, the monoclonal auto-antibody activity is asymptomatic and polyspecific, as it is only the monoclonal expression of polyclonal natural auto-antibodies. A comprehensive review of the various antibody activities of monoclonal immunoglobulins is presented. With the presence, in large quantities, of monoclonal immunoglobulins and their antibody activity, the links between dysglobulinemia and autoimmune disease are discussed as well as the pathogenic role of auto-antibodies.