224 LOCAL TLSSUE REAC^TIVITY 



liii(liiit;s of ac id last l)a( illi in al)()iit lo j)ci cent ol the ini(c. and 

 the hiiij)h()( yti( characlei ol the lesions were held to in(Hcate 

 that the haeilli established themselves in the tissues. Accordino to 

 this author, there was j:)resiunj)ti\'e evidence that the B. luhcr- 

 cnlo.sis \\'[\s the indirect but essential at'cnt in the promotion ol 

 neo])lasti( i>i()\vth in his mice. 



Roskin and Kxempliarskaia (iQ^^i) studied the effe( t ol try- 

 panosoma infection on Ehrlich's adenocarcinoma of the mouse 

 and on hypernephroma of the oiiinea ])ig. Trylxuiosonia criizi in- 

 fections ^vere produced simidtaneously. before or -after tumor 

 transplantations. Forty-five ttniior-bearing mice were infected ^vith 

 Tryjjanosoma cruzi; in 30 mice the tumor disajjpeared and in 15 

 its development was definitely inhibited. The injection of mice 

 with B. melitensis had no effect upon the tumor development. 



Forty-five guinea pigs were infected by these authors ^vith Try- 

 IxDiosoma equinnm. While exerting a certain inhibitory effect 

 the infection did not induce regression of the tumor. It is inter- 

 esting in connection with data to be presented later, that micro- 

 scopic examination of the tinnors showed large groups of "dis- 

 solved" cells which did not resemble those seen in necrosis. The 

 parasites were accinntdated in the vessel hunina. Some Avere 

 found ^vithin the timior cells ^vhose nuclei presented signs of de- 

 generation. The intracellidar parasites had an atypical appearance 

 ^vhich suggested that the symbiosis of the timior cells and the 

 parasites residted in a mutual inhibition of their vital functions. 



Following inoculation ^vith Trypmiosoma equinuni, Karczag, 

 Csaba and Nemeth (1931) obtained no decrease in the incubation 

 period necessary for development of Ehrlich's adenocarcinoma in 

 mice. In one group in Avhich tumors ^vere transplanted after the 

 development of trypanosomiasis, there w^as possibly a prolongation 

 of the incid)ation period for timior gro^vth, and also possibly, at- 

 tenuation of malignancy of the neoplasm. 



Lazzarini (1927) inoctdated mice ^vhich ^vere considered re- 

 sistant to tumors, ^vith a mixtme of bacteria isolated from a spon- 

 taneous epithelioma of the mouse. The experiment \vas carried 

 out on 15 mice, 2 of these developed a cystic tumor at the site of 

 the inoculation. This author thought that the inoculation of the 

 bacteria served as a mechanical irritating stimidus. 



According to Cohn and Collier (1933) , infection with B. tuber- 

 culosis may exert an inhibitory effect on the development of 



