98 ENZYMES 



nature. The leucocytic proteases, however, seem not to attack either 

 toxins or Uving bacteria (Jochmann). Bertohni'° states that auto- 

 lyzing hver will destroy diphtheria toxin. 



On the other hand, there are many pathogenic bacteria which do 

 not secrete their toxic materials, but store them up within the cell 

 body, e. g., typhoid, cholera, and, indeed, the majority of pathogenic 

 forms. These endotoxins are probably hberated from the bacteria 

 only through digestion of their cells, either by their own autolytic 

 enzymes or by the enzymes of the infected tissues and leucocytes. 



Leukemia. — The abundant elimination of uric acid and other pu- 

 rine bodies in the urine in leukemia testifies to the great amount of 

 destruction of nucleoprotein that is going on during the disease, and 

 these are probably derived from the autolysis of leucocytes, which per- 

 haps depends on the relatively large proportion of leucocytes to 

 serum. Schumm'^^ has found that leukemic spleens and bone marrow 

 autolyze rapidly and completely, and he isolated many of the cleavage 

 products of protein digestion from such autolysates. 



Leucocytes from myeloid leukemia hquefy alkaline gelatin vigor- 

 ously, but those from lymphatic leukemia do not; the liquefaction is 

 inhibited by normal serum (Stern and Eppenstein).''^ By the serum 

 plate method this observation has been much extended, and the hetero- 

 lytic action of the leucocytes has been found limited to the neutro- 

 phile granules. In neutral media evidence is obtained of the presence 

 of protease in the lymphocytes of chronic lymphatic leukemia and the 

 leucocytes of acute and chronic myeloid leukemia; maltase, lipase and 

 amylase are found in both types of cells, and oxidase in the granular 

 cells derived from the marrow (Morris and Boggs).'^^ v. Jaksch,"^ 

 Erben,'^^ and others have noted the occurrence of peptones and albu- 

 moses in leukemic blood, particularly if removed postmortem. The 

 improvement in leukemia that follows .r-ray treatment is associated 

 with an increased nitrogen elimination, probably due to autolysis of 

 disintegrating cells, '^^ although a;-rays have no appreciable effect upon 

 the leucocytic proteases in vitro (Miiller and Jochmann). (See also 

 "Leukemia," Chap, xiii.) 



Tumors. — Probably because of the great amount of necrosis that 

 is constantly going on in all malignant growths, with subsequent di- 

 gestion of the dead cells, autolytic products are present in them in 

 very considerable amounts. This was first demonstrated by Petry," 



'"' Biochem. Zeit., 1913 (48), 448. 



^' Hofmeister's Beitr., 1903 (3), 576; 1905 (7), 175. 



^^ See discussion of leucocytic enzymes, p. 89. Longcope and Donhauser (Jour. 

 Exper. Med., 1908 (10), G18) found proteases in the large lymphocytes in acute 

 leukemia, which were most active in an alkaline medium. 



" Arch. Int. Med., 1911 (8), 806. 



'^ Zeit. f. physiol. Chem., 1892 (16), 243. 



'^Zeit. f. klin. Med., 1900 (40), 282; Zeit. f. Heilkunde, 1903 (24), 70; Ilof- 

 meiter's Beitr., 1904 (5), 461. 



'6 Musser and Edsall, Univ. Penn. Med. Bull, 1905 (18), 174. 



" Zeit. f. physiol. Chem., 1899.(27), 398; Hofmeister's Beitr., 1902 (2), 94. 



