194 ANTI-BACTERIAL PROPERTIES OP SERUM 



concluded that human serum contained a multiplicity of bacteriolytic 

 complements. Buxton 1 (1905) investigated the changes produced 

 in the serum after it had killed a certain amount of a given bacterium. 

 His results showed that a serum which had killed the typhoid bacillus 

 might have lost bactericidal effect on that organism, while it retained 

 it for the paratyphoid bacillus ; the converse also held good. On 

 the other hand, the killing of cholera organisms removed the bacteri- 

 cidal power in the case of both the bacilli mentioned. Steinhardt 2 

 (1905) found that the bactericidal effect both for typhoid and 

 dysentery bacilli was removed by treatment with dead culture of 

 either of these organisms, and was partially restored by the addition 

 of heated serum (natural immune-body). She ascribed the result 

 to the presence of a common immune-body which was removed by 

 dead culture of either organism, there being at the same time a non- 

 specific reduction in complement. Forster 3 (1905) obtained, as 

 regards typhoid and cholera organisms, similar results in the case of 

 goat serum to those of Wright and Windsor in the case of human 

 serum. He also found that a large amount of typhoid immune serum 

 produced deviation of complement (' Neisser-Wechsberg phenome- 

 non ') for the cholera spirillum as well as for the typhoid bacillus 

 a result which is different from that obtained by Buxton (loc. cit.). 



The subject is one of great complexity, and involves the 

 question as to the existence of natural immune-bodies, and 

 also that as to multiplicity and specificity .of complements. 

 At present it is not possible to bring the results of different 

 workers into harmony and draw general conclusions. In 

 our experiments we have used guinea-pig's serum through- 

 out, and we may mention at the outset that we have met 

 with considerable variations in the properties of the serum 

 of different guinea-pigs. The results given, however, are 

 those drawn from a large series of experiments. 



1 Buxton, Journ. Med. Research, 1904-5, vol. xiii, pp. 305, 431, 461. 

 a Steinhardt, ibid, 1905-6, vol. xiv, p. 161. 

 3 Forster, Lancet, 1905, vol. ii, p. 1531. 



