THE LEUCOCIDINE OF THE STAPHYLOCOCCI. 143 



Lastly, specific hcemagglutinines obtained from the filtrates 

 from bacteria e.y. t from staphylococcus and different vibriones 

 have recently been described by KRAUS and LuowiG. 1 They 

 are destroyed at 58 C. and form specific anti-bodies. They 

 must be kept quite distinct from the specific hsemolysines. 



A lysine of the plague bacillus has also been described by 



IJRIARTE. 2 



THE LEUCOCIDINE OF THE STAPHYLOCOCCI. 



Simultaneously with the production of- lysine there is formed 

 in the case of the typical species of staphylococci a second soluble 

 toxine, leucocidine, which was independently discovered by VAN 

 DE YELDE (loc. cit.) and by BAIL, S and was more closely studied 

 by NEISSER and WECHSBERG. 4 Its specific activity is directed 

 mainly against the leucocytes, which it kills and dissolves, and 

 also against certain other cells, such as hsematoblasts, ganglionic 

 cells, &c. Owing to the fact that it appears to destroy the 

 leucocytes in the living organism also, it produces infarct and 

 other alterations in the kidneys. It does not appear, however, 

 to have a specific action upon the epithelium of the kidneys. 

 NEISSER and WECHSBERG tested its activity by means of their 

 " bioscopic method" in which they took the reducing power of 

 the leucocytes as the measure of their vitality, a dilute solution 

 of methylene blue being used as the indicator. If the leucoci- 

 dine was active no decolorisation of the methylene blue took 

 place. In such determinations it is obvious that the quantity of 

 leucocytes present must be taken into account; this was done 

 by determining beforehand the single reducing dose, L r , for each 

 exudation from the living cells, and taking this result as the 

 basis of the calculation. 



Leucocidine is produced in bouillon cultivations in about four 

 days, and reaches its maximum in about eight days. As regards 

 the influence of the alkalinity of the culture fluid almost the 

 same conditions appear to hold good for leucocidine as for 

 staphylolysine. 



Leucocidine invariably occurs in association with the lysine. 



1 Krausand Ludwig, "Ueb. Bakteriohamagglutinine," Wien. Idin. Woch., 

 1902, 120. 



2 Uriarte, " H^molysine du bac. pesteux.," Soc. BioL, Ivii., 254, 1904. 



3 Bail, "Ueber leukocide Substanzen in den Stoffwechselprodukten d. 

 Staph. pyog. aureus," Arch. f. Hyg., xxxii., 133, 1898. 



4 Neisser and Wechsberg, "Ueber eine neue einfache Methode z. Beob. 

 von Schadigungen leb. Zellen und Organismen," Munch, med. Woch., 

 1902, 1261. 



