THE CULTIVATION OF THE LEPROSY BACILLUS. 



By Moses T. Clegg. 

 [From the Biological Laboratory, Bureau of Science, Manila, P. I. 



At tlie Sixth Annual Meeting of the Philippine Islands Medical As- 

 sociation which was held at Manila^ February 11, 1909, I made a prelim- 

 inary report ^ upon the cultivation of the Bacillus lepra. In this report 

 I stated that I had succeeded in cultivating, from the spleen and skin 

 nodules of typical cases of leprosy, an acid-fast bacillus which grew upon 

 agar in symbiosis with amosbge. The amoebae had been obtained from a 

 dysenteric stool and were cultivated with, the cholera vibrio. 



At the time of the first publication, the acid-fast organism had been 

 obtained in symbiosis with amoebae from the spleen in two cases and 

 from skin nodules in three other cases of leprosy, but had not been 

 isolated in pure culture. Since then similar cultures have been obtained 

 from leprous tissue in three additional cases and from two of these the 

 acid-fast organism has finally been isolated in pure culture. 



In continuing the work of cultivation I have used the same technique 

 described in the preliminary report, always making the original inocula- 

 tions from the leprous tissues upon cultures of amoebae with the cholera 

 vibrio. 



Among the sources of experimental error which were mentioned in 

 the previous communication was the possibility that the acid-fast organism 

 had been growing originally with the amoebae in the human colon. In 

 order to rule out this possible source of error amcebte obtained from a 

 different source than those used in the first experiments, namely, from 

 the tap water, have been cultivated with the cholera vibrio and these 

 cultures used for the original inoculations with leprous material. 



No acid-fast bacteria have been found in the cultures of the water 

 amoebae excepting after inoculation with material from a case of leprosy, 

 so that the source of error under discussion can be excluded. Furtbcr- 

 more, since the cultivation of the acid-fast organisms has been successful 

 with amoebae obtained from a case of dysentery as well as those from 

 tap water, it is not probable that any importance attaches to the strain 

 of amoeba used. It is important, however, for the successful cultivation 



^This Journal, Sec. B (1909), 4, No. 2, 77. 



403 



