THERAPEUTIC IMMUNIZATION IN MAN 515 



logical studies in congenitally syphilitic children has seen phagocy- 

 tosis or at least intracellular localization of treponemata in the alveo- 

 lar cells of the lung and in the parenchyma cells of the liver and 

 kidneys. For reasons not entirely clear to us, he interprets the 

 former as true phagocytosis and the latter as a penetration of the 

 t,reponemata into the liver cells to the detriment of the latter. We 

 ourselves have occasionally seen phagocytosis in sections of syphilitic 

 rabbit testes, but in all cases the process was not a very active one 

 and not much can be said about its importance at present. As a 

 matter of fact, Hopkins and the writer, 170 in studying the mechanism 

 of the natural resistance of mice against syphilis, injected virulent 

 organisms into the peritoneal cavities and observed the treponemata 

 in peritoneal puncture fluid, alive, actively motile, and unphagocyted, 

 though surrounded by masses of leucocytes, as long as three days 

 after their injection. It seemed almost as though the natural im- 

 munity of such animals might be similar to the "atreptic" cancer 

 resistance spoken of by Ehrlich. The treponemata did not multiply 

 in the mice but though, naturally, diminishing in number, were ap- 

 parently neither killed nor even inhibited in motility by the perito- 

 neal exudates and, for several days, swam in and out among the 

 accumulating leucocytes, often adhering to them peripherally but 

 not taken up by them. Lack of entirely satisfactory methods of 

 staining cells containing treponemata make it difficult to speak 

 with certainty of the actual occurrences. But we gained the distinct 

 impression that the treponemata were not actively injured or de- 

 stroyed until they had spontaneously died out owing to lack of 

 suitable environment, i. e., nutrition. 



In the case of natural immunity at any rate, we do not think that 

 phagocytosis by the mobile leucocytes plays a primarily important 

 role. However, these experiments will need further elaboration. 



The search for antibodies gained new vigor when the efforts of 

 Schereschewsky, 171 Miihlens, 172 Hoffmann 173 and especially Nogu- 

 chi, had resulted in successful cultivation of treponemata from syphil- 

 itic lesions in man and animals. It was hoped that with the causative 

 organisms isolated, immunization and a clear understanding of the 

 antibodies in syphilis might yield practical results. Kolmer 174 ob- 

 served that cultivated treponemata were agglutinated in the sera of 

 rabbits treated with culture material, and such agglutinins were pro- 



170 Zinsser, H., and Hopkins, J. G. Jour. Am. Med. Assn., 1914, Ixii, 

 1802 ; Jour. Exper. Med., 1915, xxi, 576. 



171 Schereschewsky, J. Deutsch. med. Wchnschr., 1911, xxxvii, Nos. 20 

 and 39. 



172 Miihlens. Treponema Pallidum in v. Prowazek Handbvch der Paihog. 

 Protozoen, i, Barth, Leipzig, 1912 ; Klin. Jahrh., 1910, xxiii, 339. 



173 Hoffmann. Berl. klin. Wchnschr., 1905, No. 46. 



174 Kolmer, J. A., Williams, W. W., and Laughbaugh, E. E. Jour. Med. 

 Research, 1913, xxviii, 345. 



