90 ENZYMES 



fluid the leucocytes all disappear in from three to sixty-three days, and 

 in 24 hours the count has been observed to drop from 392 to 6.^* The 

 leucocytic enzymes seem to be very resistant against chemicals, 

 especially against formaldehyde, so that museum specimens of leuk- 

 emic tissues preserved in formalin for years are still proteolytic. Liver 

 tissue is but slightly proteolytic by this test, spleen more so, and leuco- 

 cyte-containing fluids, such as saliva and colostrum, are quite active. 

 Pancreas tissue, has, of course, strong proteolytic action, but it is 

 shown to be distinct from the leucocytic protease bj^ being inhibited 

 by certain sera that do not inhibit the leucocytic protease. In gen- 

 eral, tissues do not cause much proteolysis of serum plates unless 

 they are invaded by many leucocytes, which applies also to tumors, 

 including multiple myelomas. 



Besides proteases, leucocytes contain other enzymes. ^^ To quote 

 the summary by Morris and Boggs^^ "it has been shown that the 

 normal and pathological neutrophile leucocytes and myeloblasts 

 contain an oxidase and probably a lipase and an amylase; myeloblasts 

 contain an amylase. In lymphoid tissues two proteases and a lipase 

 have been shown to exist. In leukemia leukoprotease has been demon- 

 strated in the myeloid variety of the disease, while it has not been 

 found in chronic lymphoid leukemia. Lipase has been demonstrated 

 in two cases of myeloid leukemia, and oxidase in all mj^-eloid cases 

 observed in which the neutrophilic cells were present in excess." 

 Jobling and Strouse,^^ confirming Opie's observation of two distinct 

 proteases in leucocytes, find also evidence of an ereptic enzyme acting 

 in either acid or alkaline fluids. ^^ 



Pneiunonia. — In the stage of resolution lobar pneumonia presents 

 a striking example of autolysis. The often-remarked phenomenon 

 that the lung tissue itself is not in the least affected, while the dense 

 contents of the alveoli are rapidly dissolved and removed is explained 

 by the invariable immunity of living cells to digestive enzymes. Ex- 

 cept for some slight possible assistance by the alveolar epithelium 

 and the enzymes of the serum, the enormous and rapid digestion of 

 pneumonic exudates is accomplished by the leucocytic enzymes. The 

 rapid rate of digestion may be accounted for by the absence of circu- 

 lation within the alveolar contents, which permits the leucocytes to 



" Bonaba, Anales de le Facultad de Med., 1919 (4), 111. 



'^ According to Tschernoruzki (Zeit. physiol. Chem., 1911 (75), 216) amylase, 

 diastase, catalase, peroxidase, and nuclease, but not lipase. I also found uricase 

 absent from dog leucocytes (.Jour. Biol. Cnem., 1909 (0), 321). Fiessinger and 

 Marie (Compt. Rend. Soc. Biol., 1909 (67), 177) state that the lymphocytes 

 contain lipase, although myeloid cells do not. (See also Resch, Deut. Arch. klin. 

 Med., 191.5 (118), 179). Leucocytes are also said to contain a "lipoidase" s])lit- 

 ting choline from lecithin (Fiessinger and Clogne, Compt. Rend. Acad. Sci., 1917 

 (165), 730. 



i« Arch. Int. Med., 1911 (8), 806. 



"Jour. Exj). Med., 1912 (16), 269. 



1* Concerning enzymes of normal leucocytes see also Fiessinger and Clogne, 

 Ann. de M^-d., 1917 (4), 445; Parker and Franke, Jour. Med. Res., 1917 (37), 345. 



