292 



Scientific Proceedings (116). 



hemolyzed 0.1 c.c. of a 5 per cent, suspension of packed sheep-cells 

 in the presence of 0.1 c.c. (2 units) of pooled guinea-pig comple- 

 ment after 15 minutes incubation in the water-bath. It was 

 observed also that extraction periods of 5, 10, 15 and 20 minutes 

 did not show any marked differences in the number of hemolysin 

 units extracted by the corpuscles. A study of the effect of tem- 

 perature on the rapidity of hemolysin extraction, indicated but 

 a small increase in the number of units extracted at water-bath 

 as compared with ice-box temperature. 



With this data on hand, a quantitative study was undertaken 

 of the hemolysin absorption capacity of 0.05 c.c. of packed sheep- 

 cells when employing different concentrations of hemolysin. Ac- 

 cordingly 0.05 c.c. quantities of centrifugalized cells were added to 

 a series of tubes each containing different quantities of hemolysin 

 in 1 c.c. quantities of saline. The extractions were carried out for 

 10 minutes at room-temperature, after which period the cells were 

 thrown down by rapid centrifugation and the number of unab- 

 sorbed hemolysin units remaining in the supernatant fluid, de- 

 termined. The following table gives the results obtained in one 

 of a series of such experiments. 



Table Showing the Effect of the Concentration of Hemolysin on the 

 Absorption Capacity of 0.05 c.c. of Packed Sheep-Cells. 



Tube No. 



No. of 

 Units 

 Per c.c. 





No. of Units 



in Super- 

 natant fluid. 



No. of 

 Units 

 Extracted. 



1 



14.300 





0.05 c.c. packed sheep- 



5.550 



8.750 



2 



10,725 





cells added to each tube 



2,500 



8,225 



3 



7.ISO 





and extraction permitted 



1,250 



5.900 



4 



3.575 





for 10 minutes at room- 



199 



3.376 



5 



2,860 





temperature, followed by 



150 



2,710 



6 



2.145 





rapid centrifugation. 



67 



2,078 



7 



1.430 







33 



1.397 



8 



715 







10 



705 



9 



357 







1 



356 



10 



178 







0 



178 



The marked affinity of sheep-cells for anti-sheep hemolysin 

 is well illustrated in this table. In similar studies by Morgenroth 

 and Arrhenius, 2 an hour extraction period was employed, while the 

 quantity of sheep-cells used for extraction is not stated. 



2 Arrhenius, S., "Immunochemistry," 1907, p. 150. 



