237 



loxic concentration of the antigen, is donbtless a cpiestion of 

 anaphylaxis. P^uiihcr exi)erinients should l)e lalvcn up again. 

 Precipitin reactions liave also been studied a little by 

 the means of tissue cultivation, (Przygode ^*^). 



2. Tissue culture as a bacleriological method. Effect of 

 bacteriotoxins on living tissue cells in vitro. 



The idea of studying the interaction of bacteria and 

 hving tissue cells in close proximity directly under 

 the microscope in tissue cultures was put into practice 

 l)y Smyth "9) ^^o) 48i) q^c would think that tissue culliu'es 

 might be the most excellent experimental method for the 

 study of various pathogenic bacteria. Undoubtedly the tissue 

 cultures may, in many cases, be the culture method 

 for living virus of varying nature, which hitherto have 

 withstood all attempts at a successful cultivation in vitro 

 such as poliomyelitis, vaccina, rabies, typhus fever and 

 many others. The conditions within a tissue culture are very 

 similar to those of the body, in any case in respect to the 

 composition of the culture medium and many pathogenic 

 bacteria, probably also these of the ultra visible may be cul- 

 tivated successfully in that manner. The virus of the Pey- 

 ton Rous chicken sarcoma, which must be considered 

 as a ultravisible virus, can be cultivated in vitro after the 

 method I have devised, and it is therefore the first fillrable 

 virus which has been propagated indefinitely outside the 

 body. 



S m y t h ^^9) 480) 48i) 482) 483) studlcd the bac. typhi, bac. 

 diphteria. bac. pseudo-diphteria, bac. coli, micrococcus 

 aureus and bac. prodigiosus in cultures of both embryonic 

 as well as adult tissues of chicken, mostly heart tissue. 

 The author claims that the technique of tissue cultivation in 

 vitro is a valuable addition to the methods of bacteriological 

 study. He is absolutely right in this; it does not seem to be 

 realized so far; possibly the use of so complex a technique 

 frightens. 



