TUBERCULOSIS TUBERCULIN THERAPY 669 



formation of connective tissue which encapsulates the focus; with this 

 there is also associated the local production of antibodies. 



The Use of Living Tubercle Bacilli. Any vaccine that will give 

 complete immunization against the tubercle bacillus and all its products, 

 in addition to a healing focal reaction of the right degree, will prove 

 of the greatest value in active prophylactic and curative immunization. 



As has been stated repeatedly, this is probably best obtained by using 

 living cultures in such form that they cannot produce the disease. 

 Obviously, it is a difficult matter to find such a culture or to modify 

 one to meet the requirements at hand. When this problem is solved, 

 it may then be possible to provide universal prophylactic immunization 

 and to aid the actually diseased in overcoming their infection. At 

 present the tuberculins are not adapted for prophylaxis because they 

 possess only partial immunizing powers, although these effects may be 

 of distinct aid to the tuberculous patient, in addition to producing a 

 focal reaction of value in walling off a lesion and producing local anti- 

 bodies. 



Probably the first work done with the living bacillus was that of 

 Dixon 1 with attenuated cultures. This worker found that animals 

 inoculated with an old culture containing club-shaped and branching 

 forms of tubercle bacilli would resist subsequent inoculation with viru- 

 lent organisms. Since then numerous investigators Trudeau, 2 Pear- 

 son, 3 de Schweinitz, 4 McFadyean, 5 Levy, 6 Pearson and Gilliland, 7 

 Behring, 8 Thomassen, 9 Neufeld, 10 Theobald Smith, 11 Webb and Wil- 

 liams, 12 and others have, either directly or indirectly, supported this 

 original work, thus indicating that the most effectual active immuniza- 

 tion is secured by using living cultures. The method employed by Webb 

 and Williams is worthy of special mention, inasmuch as the ascending 

 doses of bacilli are actually counted by an ingenious method devised by 



1 Medical News, Philadelphia, October 19, 1889. 



2 Amer. Jour. Med. Sci., August, 1906; June, 1907; New York Med. Jour., 

 July 23, 1893; Medical News, October 24, 1903. 



3 Proc. First Internat. Vet. Congress, 1893. 



4 Medical News, December 8, 1894. 



5 Jour, of Comparative Path, and Therap., June, 1901; March, 1902. 



6 Centralbl. f. Bakt., 1903. 



7 Phila. Med. Jour., November 29, 1902; Univ. of Penna. Med. Bull., 1905. 



8 Beitrage z. exper. Therapie, Reft. s. Marburg, 1902. 



9 Recuil de Med. Vet., January 15, 1903. 



10 Deutsch. med. Wochenschr., September 1, 1902; April 28, 1904. 



11 Jour. Med. Research, June, 1908. 



12 Trans, of the Sixth Internat. Congress on Tuberculosis, 1908; Jour. Med. 

 Research, 1911, xix, 1. 



