In 1892 Maragliano1 directed attention to the fact that the blood serums of patients afflicted with various diseases exerted a destructive influence on the blood corpuscles of healthy individuals, and also on the corpuscles of pathologic cases and set free hematoidin. He expressed the opinion that the reduction in sodium chlorid in the blood in different conditions of disease was a factor in the solution of red cells. This appears to be the first observation on isolysins of human serums.
Ehrlich and Morgenroth2 demonstrated that the blood serums of goats that had been immunized by homologous blood corpuscles contained isolysins, the serums of the immunized goats being hemolytic for the corpuscles of other goats.
Von Dungern,3 on the other hand, found that the serums of guinea-pigs that had been immunized with the tracheal epithelia of cattle was not only destructive to the tracheal epithelia of the latter,