THIELE AND EMBLETON'S EXPERIMENT 39 



moiety into harmless derivatives. And these anaphylactic 

 phenomena are obtainable, let me repeat, by the introduction 

 of bacterial proteins into the tissues, and even of living 

 bacteria. 



So long ago as 1904, W. V. Shaw, 1 and later Schloss and 

 Foster 2 in 1913, called attention to the fact that in monkeys 

 arthritis only occurs after a second intravenous injection of 

 streptococci, the first setting up no obvious changes. In 1911 

 my late colleague in Montreal, Dr. Duval, 3 now Professor of 

 Pathology at Tulane University, New Orleans, when studying 

 the bacteriology of leprosy made the curious observation that 

 while by a single inoculation of the bacilli which he had isolated 

 and cultivated he was unable to produce lesions in monkeys 

 (Macacus rhesus), lepra nodules containing the bacilli could be 

 obtained as the result of inoculations repeated at short intervals. 

 He and Couret conclude (p. 303) : " That the infection is more 

 likely to follow where sensitization is first established is definitely 

 proved by the specific experiments that we have carried out upon 

 a variety of laboratory animals. The first injection, we assume, 

 sensitizes the animal, and may consist of either killed or viable 

 lepra bacilli." 



Now, starting from these phenomena of anaphylaxis, Thiele 

 and Embleton, 4 working at University College, were led to the 

 happy idea of introducing harmless bacteria into the tissues, 

 and then in a week or ten days later giving a second injection 

 of the same bacteria. Those first injected being non-pathogenic 

 became disintegrated, and liberating their proteins were found 

 so to influence their host that upon a second injection into the 

 now susceptible animal, the bacteria, instead of being destroyed, 

 took on active growth, and what is more, the anaphylactic 

 state, by permitting the active growth within the weakened 

 organism, was found by them to lead to an associated adapta- 

 tion to the unaccustomed environment. 



The Bacillus mycoides is an absolutely harmless micro- 

 organism common in garden soil, and growing in nature only 

 at a low temperature. It is in fact destroyed at body heat. 



1 Journ. Path, and Bad. ix., 1904, 158. 



2 Journ. Med. Research, xxix., 1913-14. 



3 Journ. of Exper. Med. xiii., 1911, 374, and Duval and Couret, ibid, xv., 

 1912, 292. 



4 Zeitschr. f. Immunitatsforschung u. exper. Therapie, xix., 1913, 643. 



