246 A MANUAL OF BACTERIOLOGY 



bacteria experimentally in vitro, and to some extent prob- 

 ably also in the body. But in this respect there is often 

 a marked difference between the circulating blood and 

 the blood in vitro. 



Lewis and Cunningham (1872), Traube and Gscheidlen 

 (1874), Fodor (1877), and Wysokowicz showed that 

 bacteria injected into the circulation rapidly disappear, 

 and were inclined to attribute this result to the bacteri- 

 cidal properties of the blood. In the main, however, 

 this disappearance is due to lodgment in the capillaries, 

 phagocytosis, and excretion by the excretory glands. 



Hankin found that Halliburton 's cell-globulin /3 (really 

 a nucleo -protein) had marked germicidal properties, and 

 concluded that it was probably the germicidal constituent 

 of the blood-serum. Bitter, who repeated Hankin's 

 experiments, failed, however, to confirm them. To the 

 germicidal constituents of the cells and body fluids 

 Buchner gave the name " alexins." 



Grohmann performed the first experiments with extra- 

 vascular blood. He found that anthrax bacilli, after 

 a sojourn in plasma, became less virulent. Fodor, 

 adding anthrax bacilli to blood and plating at intervals, 

 found the number of organisms capable of growth 

 progressively diminished. 



Nuttall, in 1888, used the defibrinated blood of several 

 animals, rabbits, mice, pigeons, sheep, and found that it 

 destroyed the B. anthracis, B. subtilis, B. megaterium, 

 and M. pyogenes var. aureus. He confirmed Fodor's 

 results, which also showed that after a while the blood 

 loses its germicidal properties and becomes a suitable 

 culture medium. The blood or serum similarly loses its 

 bactericidal properties on heating, and serum that has 

 once been used loses its bactericidal properties. Nissen 

 continued this work, and also found that fresh serum is 

 germicidal for a variety of organisms. 



