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Scientific Proceedings (129) 



There is a very marked relation between the time of hemolysis 

 and relative surface tension. Some samples of bile have shown 

 a decrease in surface tension upon dilution with salt solution 

 and coordinate with this has occurred a decrease in the time of 

 hemolysis. When erythrocytes are treated with non-hemolytic 

 concentrations of bile, the fragility of the cells are sometimes 

 greatly decreased and sometimes increased. This corresponds 

 with clinical findings and adsorption of bile elements on the sur- 

 face of the red blood cells appears responsible for the changes 

 in fragility observed. 



In pernicious anemia a decreased or normal fragility of red 

 blood cells is found. W. P. Larson suggested some years ago to 

 the author that the hemolytic agent was probably a substance 

 with a marked surface tension reducing property. In our ex- 

 periments we determined carefully by means of a time-fragility 

 test the fragility of the cells from pernicious anemia and the 

 fragility of normal human cells from a blood of the same group. 

 The normal cells were then treated with the serum from the 

 pernicious anemia patient for varying lengths of time. These 

 treated cells were then washed several times in salt solution and 

 their fragility again measured. It was found that the treated 

 normal cells showed a marked decreased fragility and in this 

 respect appeared identical with pernicious anemia cells. Dilu- 

 tion of the pathologic serum gave similar results in varying 

 degrees. These experiments lend some additional evidence to 

 the view that the hemolytic agent is present in the serum. If 

 it is the hemolytic agent which is responsible for the decreased 

 fragility, the adsorption upon normal cells becomes a means of 

 identification of the hemolytic factor in further experimental 

 work. 



The results reported from this laboratory upon hemolysis by 

 soap, saponin and bile tend to show that the clinical fragility 

 test is no indication whatever of a corresponding condition of 

 the red blood cells. An erythrocyte partially hemolyzed by bile 

 or by castor oil soap has an increased resistance to hemolysis 

 by hypotonic salt solution. 



Thus, any change in the fragility of erythrocytes in a clin- 

 ical test, whether increased or decreased, must be interpreted as 

 an indication that the red cells are being subjected to an acceler- 

 ated hemolysis. 



