124 



Scientific Proceedings (112). 



The uterine method used in this way gives more conclusive 

 results than any other because it avoids the uncertainties that 

 always attend general anaphylactic experiments carried out on 

 guinea pigs with bacterial extracts. 



Our results so far may be summarized as follows: 



Tuberculous animals, unless inoculated with overwhelming 

 doses, always become anaphylactic to tuberculo-protein. Positive 

 uterine reaction is never obtained, however, before the end of the 

 third week, and sometimes not until the sixth week at a time when 

 the disease has made considerable progress. 



Skin reactiveness may develop in such pigs, however, as early 

 as the ninth day, long before the uterus gives any signs of general 

 anaphylaxis. 



There may, thus, exist in the tuberculous animal marked skin 

 reactivity without any uterine hypersensitiveness. 



Both skin reactiveness and general anaphylactic hypersensitive- 

 ness may fade together in the prelethal stages when the pigs are 

 very sick. 



Normal guinea pigs are easily rendered anaphylactic to extracts 

 of tubercle bacilli by injecting them intraperitoneally on suc- 

 cessive or alternate days, for ten injections, and testing them on 

 and after the eighteenth day after the last injection. 



Such anaphylactic pigs tested from the time of the last few 

 injections until the time of the fully developed hypersensitiveness 

 have never, except in two instances, given typical skin reactions, 

 and in one of these two the reaction was not as marked as in the 

 typical tuberculous animal, and in the other the possible absence 

 of tubercles could not be excluded. 



Guinea pigs sensitized experimentally with tuberculo-protein, 

 therefore, may be very highly anaphylactic as evidenced by the 

 uterus, and show absolutely no typical skin reaction. 



There are two types of skin reaction, one which resembles the 

 skin reaction obtained in human beings sensitive to horse serum, 

 etc., which develops within a few minutes or within one half 

 hour, appears to be chiefly a vascular reaction with edema, etc., 

 and which fades without subsequent inflammation within a few 

 hours. This has, occasionally, been observed in the anaphylactic 

 pigs on intracutaneous injection, and is, we believe, probably a 



