124 TOXINES AND ANTITOXINES. 



serum in a vacuum without loss, and when it was required for 

 use dissolved the residue in six times its quantity of water. 



The milk of immunised animals also contains antitoxine. 

 According to BBIEGEB and OOHN 1 it can be concentrated from 

 the milk in the following manner : 



The milk is first coagulated by means of rennet in an analogous manner 

 to that used in the preparation of diphtheria antitoxine. The filtered 

 whey is shaken with chloroform, allowed to stand, decanted, and then 

 saturated with ammonium sulphate to the extent of 32 per cent. The 

 precipitate is redissolved, a small amount of basic lead acetate added, and 

 the new precipitate washed with water rendered very slightly alkaline. 

 The filtrate and washings are now saturated with ammonium sulphate, and 

 the resulting precipitate mechanically freed from the excess of solid 

 ammonium sulphate by stirring it with pure chloroform. The salts fall 

 to the bottom, while the light compound of the anti-bodies rises to the 

 surface and is removed. In this way it was possible to concentrate the 

 antitoxine to the extent of 300 to 400 times the strength of that originally 

 present in the milk. A still further purification of the antitoxine can be 

 effected by treating the filtrate, after removal of lead, not with ammonium 

 sulphate, but first with sodium chloride, and then with sodium phosphate. 

 Practically none of the antitoxine is precipitated with the sodium chloride 

 precipitate, whereas it is nearly all carried down by the sodium phosphate 

 precipitate. 



The properties of the antitoxine have naturally received much 

 attention. It does not differ materially from diphtheria anti- 

 toxine. It is partially destroyed at 68 C., though not completely 

 so even at 80 C. Acids (hydrochloric acid, in the proportion of 

 1 part to 15 of antitoxine, and lactic acid) have also a destructive 

 influence. 



Very weak alkalies do not injure it, but, when concentrated, 

 rapidly destroy it. It does not readily putrefy (BEHRING). 



It is not dialysable, and is partially retained by Chamberland 

 porcelain filters. TIZZONI and CATTANI 2 attribute to it the 

 nature of a ferment, for which, in my opinion, there is no 

 justification (see under Diphtheria). They draw this conclusion 

 from the fact that it can be precipitated by alcohol, and can be 

 extracted, though slowly, from the precipitates by means of 

 glycerin. Doubtless, like diphtheria antitoxine, it is also a 

 substance closely allied to the globulins. 



1 Brieger and Cohn, "Beitr. z. Concentr. geg. Wundstarrkrampf 

 schiitzenden Substanz.," Zeit. f. Hyg., xv., 439, 1893. 



2 Tizzoni and Cattani, " Sur les propriete's de 1'antitoxine du tetanos," 

 Arch. ital. d. BioL, xvi., 394 (abstract), 1891; "Ueber d. Eigenschaften 

 des Tetanus- Antitoxins," CentralU. /. Bdkt. t ix., 685, 1891; "Fernere 

 Unters. ub. das Tetanus Antitoxin," ibid., x., 33, 1891 ; Tizzoni, "Ueb. d. 

 experim. Immunitat gegen Tetanus," Festschr. fur Virchow, Berlin, 

 iii., 29, 1892. 



