480 EXPERIMENT STATION EECOED. 



conglutinin-fixins: bodies, however, remain much longer in the blood stream 

 than the complement-fixing bodies, and from this standpoint the method should 

 be employed where an absolute diagnosis of glanders is desired. 



The advantage of using' larger amounts of extract in conducting the com- 

 plement fixation test for diagnosing glanders, Eckebt (Mitt. Kaiser Wilhelms 

 Inst. Landw. Bromherg, 6 {1914), ^^o. 4, pp. 298-^05; ahs. in Berlin. Tierdrstl. 

 Wchnschr., 30 {1914), No. 33, p. 60'2). — As a rule, in this method a 1 per cent 

 glanders bacillaiy extract is used, but it has been observed in some cases that 

 the use of a solution of this sti'ength declared horses free of glanders which, 

 on clinical examination or on autopsy, were found to be affected with the disease. 

 When an extract of 5 per cent was used for each 0.2 cc. of serum, the sera of 

 many of the horses which did not react with the lower concentration indicated 

 that glanders might be present. The highest bacillary extract concentration 

 recommended by the author is 10 per cent. 



Studies in the immunity to tubercular disease. — I, The caseation of the 

 tissues, C. C. TwoKT {Vet. Jour., 10 {1914), No. 473, pp. 543-551).— This article 

 discusses "what takes place in the presence of the tubercle or other bacilli 

 producing caseation, and, on the other hand, what takes place in the presence 

 of Johne's bacillus. 



" In the case of the tubercle bacillus, the soluble toxin secreted probably does 

 not act detrimentally on the surrounding cells, but may even act as a stimulant, 

 so that phagocytosis of the bacilli is in no way interfered with. This toxin 

 may have an influence in causing encapsulation of the diseased area, and thus 

 more or less isolation from the other tissues of the body. Meanwhile the bacilli, 

 both intra- and extra-cellular, but especially the former, commence to be disin- 

 tegrated to the humors of the host. The products of this disintegration lead 

 to a further fabrication of the specific lysin, while at the same time, if it 

 becomes too great in amount, the animal cells are unable to survive, as the in- 

 termediate products of the breaking down of proteids are intensely toxic for 

 the cells of the animal body. The increase of the specific lysin leads to further 

 destruction of the bacilli, and this in turn to the liberation of more endotoxins, 

 so that ultimately the cells inside the nodule are doomed to destruction. Thus 

 the cells and bacilli within the constricted area react upon one another, and 

 both in the end are killed out, the edges of the nodule, where the accumulated 

 toxins can more easily be got rid of, being the only situation in which intact 

 cells and bacilli can be found. Bacilli, apparently normal, may be found in the 

 center of the caseous mass, but rarely any intact cells ; and it is quite probable 

 that many of the bacilli here found are really dead. 



" In Johne's disea.se it is highly probable that little or no soluble toxins are 

 produced, and the bacilli, although actively phagocytosed, are not toxic for the 

 cells, and can live and multiply within them. At the same time, if a certain 

 number of bacilli die or are killed by the host, the products of disintegration 

 are better able to get away than in tubercular disease, as the lesions are never 

 encapsulated, but blend more or less imperceptibly with the normal tissues. 

 In leprosy the lesions are often encapsulated, but here again it is probably due 

 to the nontoxicity of the bacilli for the cells, and especially on their ability to 

 live and multiply within the cell.s, that there is an absence of caseation. The 

 disintegration products of Johne's bacillus and the leprosy bacilli are as toxic 

 for the animal as a whole, or locally for its tissues, as those of the tubercle 

 bacillus. This is seen by the reaction produced on inoculation of a diagnostic 

 vaccine on the one hand, and the effect produced by the inoculation of an emul- 

 sion of dead bacilli on the other, when with all three diseases, and with all 

 three bacilli, the results are the same, that is to say, a rise of temperature in 

 the first case and caseation of the tissues in the second." 



