Local Injection of Foreign Leucocytes. 



3 



for these animals. Rabbit leucocytes injected into the meningeal 

 cavities of dogs invariably cause death. A single injection of 

 horse leucocytes, however, can be safely made in normal dogs, 

 although on repeating the injection, or on injecting horse leu- 

 cocytes for the first time into meninges already the seat of an 

 inflammatory lesion, death results. 



The injection of horse leucocytes into the cerebral meninges of 

 dogs, simultaneously with the inoculation of the meninges with 

 tubercle bacilli, causes a slight delay in the development of the 

 paralytic symptoms in about half of the treated animals. This 

 delay, however, is very slight when compared with the great 

 prolongation of the latent period previously observed, 1 after treat- 

 ment with homologous leucocytes. 



In the same report, it was shown that foreign leucocytes are 

 much less toxic for monkeys. Both rabbit leucocytes and horse 

 leucocytes can be safely injected into the meningeal cavities of 

 these animals. 



The study of the therapeutic control of meningeal tuberculosis 

 in monkeys is made difficult by extra-dural leakage, when the 

 inoculations and treatments are made by the method of lumbar 

 puncture. The inoculations and treatments, in the later experi- 

 ments herein reported, were therefore made through a permanent 

 wax-trephine 2 opening in the skull. 



The injection of foreign leucocytes into the meningeal cavities 

 of monkeys, either simultaneously with the inoculation with 

 tubercle bacilli, or subsequent to the inoculation has thus far 

 given no definitely positive prophylactic or curative effects. In a 

 small group of monkeys, however, inoculated and treated by the 

 method of lumbar puncture, the repeated injection of rabbit 

 leucocytes was associated with a considerable prolongation of the 

 latent period in one of the treated monkeys, and by a complete 

 prevention of the subsequent tuberculosis in a second monkey. 

 The work with monkeys is being continued. 



1 Jour. Exp. Med., 1912, XV, pp. 1-13. 



2 Jour. Exp. Med., 1912, XV, p. 3. 



