39 
SENSITIZING ACTION OF EUGLOBULINS. 
Gay and Adler a reported that they were able to separate a sub- 
stance from horse serum (euglobulins) by one-third saturation with 
ammonium sulphate, which was apparently a purely sensitizing sub- 
stance without the admixture of a toxic or assimilable element of 
horse serum and which would sensitize normal animals in four or five 
days to a subsequent injection of horse serum. 
We have previously reported 6 suggestive symptoms after four or 
five days in animals that had been sensitized by the injection of 
0.01 c. c. of normal horse serum into the brain. Lewis reports that 
he has made guinea pigs quite sick on the sixth day by giving the 
second injection directly into the circulation. 
In order to determine what amounts of euglobulins would sensitize 
we gave 10 guinea pigs varying amounts of euglobulins from 0.0000001 
c. c. to 1 c. c. These animals were subsequently tested for their 
susceptibility by the injection of 6 c. c. of normal horse serum intra- 
peritoneally. Xone of the animals that received smaller doses than 
0.001 c. c. reacted. 
We have before called attention to the fact that care must be 
taken in drawing conclusions as to the different effect of various 
agencies upon the sensitizing and toxic properties of proteins, for we 
have found that only 1/1,000,000 c. c. of horse serum will sensitize a 
guinea pig and Wells has found that 1/20,000,000 of a gram of puri- 
fied egg white would do likewise. It requires considerably larger 
amounts to poison the animal. 
Table Xo. 18. — Sensitizing action of euglobulins. 
G. P. No. 
G. P. 
weight. 
First injection. 
Inter- 
val in 1 
days. 
Second injection. 
Result. 
109 
0.0000001 c. c. euglobulins 
(Natl. IX), subcutane- 
1 ously. 
229 
: 6 c.c. normal horse (Frank) 
serum, in traperitoneally. 
i No symptoms. 
108 
0.000001 c. c. euglobulins 
(Natl. IX), subcutane- 
ously. 
229 
6 c. c. normal horse (Frank) 
serum, intraperitoneally . 
No symptoms. 
107 
0.00001 c. c. euglobulins 
(Natl. IX), subcutane- 
ously. 
229 
6 c.c. normal horse (Frank); 
serum , intraperitoneally. 
No symptoms. 
106 
0.0001 c. c. euglobulins 
(Natl. IX), subcutane- 
ously. 
229 
6 c. c. normalhorse (Frank) 
serum, intraperitoneally. 
No syihptoms. 
a Gay, F. P., and Adler, H. M. : On the chemical separation of the sensitizing fraction (anaphylatin) 
from horse serum. Jour. Med. Research, vol. 18, June, 1908, p. 433. 
b Hyg. Lab. Bui. No. 29, 1906, p. 8. 
