248 THE PRINCIPLES OF IMMUNOLOGY 



tain of the ferments become active only when suitable material is pre- 

 sented, as is the case with the serum peptidase; others operate only 

 when the .surrounding medium reaches suitable reaction; still others 

 operate only if the antiferment content is sufficiently reduced. There- 

 fore, the preservation of the body tissues against destructive action of 

 'ferments and the normal processes of metabolism depend in considerable 

 part upon the neutralizing activity of antif erments. 



Antiferment. Certain investigators have reported the production 

 of specific antibodies following the injection of ferments. Morgen- 

 roth claimed to have produced a specific antirennin, Sachs and Achalme 

 an antipepsin and an antitrypsin, Schultze an antisteapsin and an 

 antilactase, Gessard an antityrosinase and Moll an antiurease. The 

 recent studies of antif erments, however, indicate that inhibitory activity 

 is not specific and this subject has been contributed to particularly by 

 Jobling and his collaborators. They are of the opinion that anti- 

 i erment activity depends upon the highly dispersed unsaturated lipoids 

 of the serum and lymph and that the titer varies with the amount of 

 lipoids, their dispersion and chemical structure. In studying anti- 

 trypsin, they found that the inhibitory substances are of the nature 

 of soaps and that the ability to inhibit ferment activity depends upon the 

 degree of unsaturation of the carbon bonds in the fatty acid. They 

 made soaps from olive oil, cod-liver oil, linseed and other oils and 

 found that these soaps inhibited the action of trypsin and leucoprotease. 

 They determined further that extraction of the blood serum with such 

 fat solvents as chloroform and ether removes the antitryptic activity. 

 Soaps prepared from the extracts restored the antitryptic activity. The 

 serum residue, after extraction, was found to be highly toxic for 

 guinea-pigs. If, however, the soap prepared from the extract were 

 added to the residue, the toxicity was neutralized. Jobling and his 

 collaborators attributed the toxic action of the serum residue to (a) 

 alteration of the mechanism of intravascular coagulation, (&) exposure 

 of native serum proteins to the action of ferments and (c) the resulting 

 formation of toxic split products. These workers isolated unsaturated 

 fatty acids from tubercle bacilli and found that when these were sapon- 

 ified they inhibited the action of trypsin but lost this power when satur- 

 ated with iodine. They were able to obtain similar soaps from caseous 

 lymph-nodes and suggest that the soaps prevent the activity of ferments 

 which would normally digest the necrotic material. This failure of 

 digestion leads to the formation of the partly-digested and fatty sub- 

 stance which is spoken of as the caseation necrosis. 



The antif erments are greatly augmented in certain diseases, such as 

 acute infections, carcinoma, cachexias in general, anaphylactic shock, 

 certain degenerative changes of the nervous system and in pregnancy. 

 Jobling explains the crisis of pneumonia as being due to an alteration 

 in the ferment-antif erment balance ; that there is a decrease in the anti- 

 ferment with a corresponding mobilization of protease, an increase in 

 the serum lipase with a resulting decrease in the non-coagulable nitrogen 

 and proteoses of the serum. 



