352 Immunising Effects of Contents of Typhoid Bacillus. [Feb. 19 r 



properties, inasmuch as the serum protected the experimental animals 

 against the bacilli, and also against an intracellular toxin obtained 

 from them. 



A simultaneous injection of (1) serum with the bacilli, and (2) serum 

 with the toxic cell-juice produced no lethal or toxic effects. The 

 control animals, on the other hand, invariably succumbed. 



It was further investigated whether the serum possessed preventive 

 and curative properties. The serum from treated monkeys was injected 

 into guinea-pigs, one injection being made in each instance, and the 

 same animals received at an interval of 12 to 24 hours lethal doses of 

 the typhoid bacillus and of its toxic intracellular juice respectively. 

 The treated animals survived the test, whilst the control animals 

 succumbed. It was therefore concluded that the serum had protective- 

 properties. 



A third series of guinea-pigs received lethal doses of the typhoid 

 bacillus and of its toxic cell-juice respectively. The serum was then 

 injected at various intervals into individual animals. It was found 

 that the lives of the animals could be saved by one injection of the serum 

 from a fatal infection or intoxication, even when half of the lethal period 

 had elapsed in each instance. The serum, therefore, possessed curative 

 properties. 



In view of the above results it appeared desirable to test the effect 

 of the typhoid cell-juices upon animals larger than the monkey, in 

 order that a greater amount of serum might be obtained conveniently 

 and tested quantitatively as regards antibacterial and antitoxic pro- 

 perties. These experiments are at present in progress, and the results 

 will be communicated in due course. 



From the experiments made upon the monkey it would appear : — 



(1.) That by the injection of the intracellular juices of the typhoid 

 organism into the monkey it is possible to obtain a serum with both 

 antibacterial and antitoxic properties, 



(2.) That such a serum possesses curative and preventive properties 

 as regards the typhoid bacillus and an intracellular toxin present in the 

 same organism. 



It is believed that this research has afforded for the first time proof 

 that, in the case of one species of pathogenic bacterium, the intracellular 

 juices of the organism, when injected into a suitable animal, give rise 

 to the production of a serum which is both bactericidal to the organism 

 itself and antitoxic as regards a toxin contained in its substance. How 

 far such properties of the cell-juice are shared by other pathogenic- 

 microbes must be the subject of further inquiry. 



Experiments have been undertaken, with the aid of the cold-grinding 

 methods referred to, with reference to other cells and organisms at the 

 Jenner Institute of Preventive Medicine, where the above investigation 

 has been conducted. 



