1909.] Hcem-agglutinins, etc., in the Blood. 



217 



usually absent. Care must always be exercised in arriving at conclusions on 

 this subject, because, unless the film preparations are made with special 

 precautions, red cells which are apparently engulfed are really extra-cellular, 

 and also, if the hsemolysins are active in the samples of serum employed, the 

 red cells which are engulfed may be either pale or difficult to recognise, and, 

 therefore, phagocytosis may be unknown. In a case of typhoid fever with 

 typhoid pyuria a high degree of phagocytosis was noted. Normal leucocytes 

 + immune red cells + normal serum showed no less than 37 red cells engulfed 

 by 50 leucocytes, while when the normal serum was diluted with immune 

 serum the phagocytosis was correspondingly reduced. In this instance 

 normal serum caused marked agglutination of immune red cells and also 

 hsemolysed them ; in another case of typhoid the phagocytic test carried out 

 in an identical manner showed 26 red cells engulfed by 50 leucocytes, the 

 normal serum in this case also haemolysed and agglutinated the immune red 

 cells, while in a still further example the immune serum + normal red cells 

 and immune leucocytes gave an active result — 50 leucocytes contained 39 red 

 cells ; when normal serum was added to the immune red cells the phagocytosis 

 was well marked, but very much less so ; here also the immune serum 

 strongly agglutinated normal red cells, but did not hsemolyse them. In 

 certain other instances of typhoid infection some degree of phagocytosis was 

 noted, but only of an indifferent type. In the case of paroxysmal haemo- 

 globinuria the immune red cells in the presence of normal serum and normal 

 leucocytes showed a high degree of phagocytosis, 50 leucocytes contained 

 39 red cells. Experiments conducted with other variations in the cells and 

 serum gave negative results. 



The normal serum in these experiments, haemolysed, agglutinated and 

 incited phagocytosis of the immune red cells, but in different degrees, the 

 most marked results occurring in the agglutination experiments, the least 

 striking were in the heemolytic. In a case of untreated secondary syphilis, 

 experimental results showed absence of haemolysis and agglutination, but 

 complemented immune serum incited a high degree of phagocytosis of the 

 immune red cells. Perhaps the most striking example of phagocytosis of the 

 red blood corpuscles occurred when the serum from a case of epilepsy was 

 added to normal red cells in the presence of normal leucocytes, 50 white cells 

 contained 46 red blood corpuscles. The immune serum also strongly 

 agglutinated these cells. Many more examples of this variety of phagocytosis 

 have occurred in the numerous experiments which have been made, but the 

 most interesting and striking results are those which I have recorded. 



All instances in which haemolysis occurs when the red cells and serum 

 interact must tend to limit the accuracy of the phagocytic experiments, 



