34 The Philippine Journal of Science wie 



While the literature contains many references to the presence 

 of natural antisheep haemolysin in human serum, very little 

 has been done toward overcoming the difficulty by finding a 

 more suitable haemolytic system. Sachs ^ gives a summary of 

 the work done, and more recently Kolmer and Casselman ^ have 

 more extensively reported on the presence in human serum of 

 haemolysins for the corpuscles of sheep, dog, ox, goat, hog, rat, 

 chicken, horse, rabbit, and guinea pig. According to the findings 

 of these authors, the hog, rat, chicken, horse, rabbit, or guinea 

 pig haemolytic systems are to be preferred to the sheep haemolytic 

 system. 



In the following report are recorded the results obtained by 

 testing fifty unheated human sera for haemolysins against the 

 corpuscles of the sheep, goat, horse, rabbit, and guinea pig and 

 the results obtained by testing fifty reactivated, heated human 

 sera for haemolysins against the corpuscles of the same animals. 



HAEMOLYSIS BY UNHEATED HUMAN SERUM 



Technique. — Fifty human sera were tested within twenty-four 

 hours of the bleeding in the following quantities: 0.4, 0.2, 0.1, 

 0.05, and 0.025 cubic centimeter. The results obtained with 

 0.025 cubic centimeters are omitted from the tables because only 

 six sera produced a trace of haemolysis, while all others gave 

 negative results. To each test tube with serum, enough physio- 

 logic salt solution (0.9 per cent) was added to make 1.5 cubic 

 centimeters; corpuscles were added in quantity of 1 cubic centi- 

 meter of a 2 per cent suspension, which brought the total quantity 

 in each test tube up to 2.5 cubic centimeters. After each tube 

 had been shaken, it was placed in the incubator at about 37° C. 

 for one hour. During this hour each test tube was shaken at 

 least four times. After an hour in the incubator the tubes were 

 allowed to stand at room temperature (25° C. to 30° C.) and the 

 results were read and recorded about three hours after the cor- 

 puscles had been added. 



Hsemolysis of sheep corpuscles. — Table I shows the results 

 obtained with sheep corpuscles. Sheep-blood corpuscles are 

 readily dissolved by fresh, unheated human serum. None of 

 these fifty human sera failed completely to dissolve the test dose 

 of corpuscles when 0.4 cubic centimeter of serum was used. 



' Kolle und Wassermann, Handbuch der pathogenen Microorganismen 

 (1913), 2, 799. 



'Journ. Infect. Dis. (1915), 16, 441. 



