120 PROPERTIES OF ILEMOLYTIC SERA 



EFFECTS OF LAKING AGENTS ON THE RECEPTORS 



In the case of such a relatively disruptive haemolytic 

 agent as water it is necessary as a preliminary to inquire 

 whether it has any destructive effect on the receptors of 

 the red corpuscles. Such an inquiry is carried out by taking 

 a given amount of red corpuscles, adding water to produce 

 lysis, and then making up with concentrated sodium 

 chloride solution so as to obtain a concentration of 0-85 per 

 cent. We then test whether such a mixture has the property 

 of taking up complement through the medium of immune- 

 body to the same extent as a suspension of the same 

 amount of red corpuscles which have not been lysed. The 

 following are the details : 



10 c.c. of a 5 per cent, suspension of red corpuscles in 0-85 per 

 cent, sodium chloride solution are taken and centrifugalized. After 

 the supernatant fluid has been pipetted off, complete lysis of the 

 sedimented corpuscles is produced by adding sterile water. The 

 mixture is left for half an hour, and thereafter 1 c.c. of an 85 per 

 cent, sodium chloride solution is added and the volume is made up 

 to 10 c.c. by the addition of water. The mixture is then thoroughly 

 shaken, and 1 c.c. is placed in each of a series of tubes. To form 

 a control series, we place 1 c.c. of the original suspension of corpuscles 

 in each of a similar number of tubes. 



We have thus two series of tubes, each tube in one 

 series containing a given amount of red corpuscles, each 

 tube in the other containing the same amount of corpuscles 

 lysed with water. To each tube in the two series we add 

 several haemolytic doses of immune-body, and then to the 

 tubes in each series increasing amounts of complement. The 

 tubes are then placed in the incubator for two hours at 

 37 C., and the presence of complement is tested for by 

 adding to each 1 c.c. of suspension of red corpuscles treated 

 with immune-body. 



Example. The above procedure is carried out. Eight doses of 



