[Inhibition of autohaemolysis in vitro by the action of isolated factors Ac III and Ac IV in so-called autoimmune haemolytic anaemias (author's transl)].

: Hyper- and autohaemolysis of red blood cells resp. in vitro by saturation of serum of patients with so-called autoimmune haemolytic anaemia is conditioned by the lack of factors Ac III and Ac IV resp., or both, in serum. When both factors are lacking also in red blood cells, in addition to hyperhaemolysis complexes are formed which in serological tests appear as antierythrocytic autoantibodies and which by a bond with red blood cells inhibit their breakdown. By adding factor Ac III and IV in suitable concentrations to serum the haemolysing effect and formation of pseudoautoantibodies is completely blocked. The results of experiments in vitro bring up the question whether autoimmune haemolytic anaemia is really conditioned by an immunological process, i. e. by autoimmunization with the formation of autoantibodies which exert an autoaggressive action or whether they are a special manifestation of deficiency of the above factors, similarly as other haemulytic syndromes which develop e. g. as a result of some enzyme deficiencies etc.