210 CHEMISTRY OF THE IMMUNITY REACTIONS 



against various types of cells other than bacteria, substances appear 

 in its serum that exercise a destructive effect upon the tj^pe of cells 

 injected. In other words, the reactions of animals to infection are 

 not specially devised for combating bacteria and their products, but 

 can be equally exerted against non-bacterial cells and their products. 

 In the case of soluble proteins, as before mentioned, the antibodies 

 show their effects by precipitating them, with agglutination of the par- 

 ticles into flocculi and perhaps a subsequent digestion; in the case of 

 cells, whether bacterial or tissue cells, the antibodies cause agglutina- 

 tion and loss or impairment of vitality. This injury may be mani- 

 fested by loss of motion in the motile cells (bacteria, spermatozoa, 

 ciliated epithelium) or by solution of their contents (bacteriolysis, 

 erythrocytolysis, leucocytolysis, etc.), or by cell death without marked 

 morphological alterations (B. typhosus, spermatozoa). If we inject 

 red corpuscles, leucocytes, spermatozoa, renal epithelium, or anj^ other 

 foreign cell, the reaction is as specific as it is if we inject bacteria, and 

 of exactly the same nature. Therefore, all that has been said pre- 

 viously concerning bactericidal substances and agglutinins can be 

 transposed to apply to immunity against tissue cells. As a matter of 

 fact, however, the transposition is generally made in the other direc- 

 tion, for red corpuscles are much easier cells to study than bacteria, 

 because their laking gives prompt and readily recognized evidence 

 that the toxic serum has brought about changes. Much of our knowl- 

 edge of bactericidal serum has been obtained through studies of the 

 mechanism of erythrocytolysis, the results of which have then been 

 applied to the subject of bacteriolysis. Both on this account, there- 

 fore, and because solution of red corpuscles is of itself an important 

 process in many intoxications and diseases, the subject is of great 

 theoretical and practical importance. 



Hemolysis-' or Erythrocytolysis 



In hemolysis the essential phenomenon consists in the escape of 

 the hemoglobin from the stroma of the corpuscles into the surroimd- 

 ing fluid. As it is not exactly known in what way the stroma holds 

 the hemoglobin normally, whether purely physically or in part chem- 

 ically, or whether the stroma consists of a spongioplasm or of sac-like 

 membranes, or both, the ultimate processes that permit the escape of 

 the hemoglobin are not finally solved. However, the agents bj' which 

 the escape is brought about are well known and extensively studied, 

 and they are found to be of extremely various natures. Thej' may 

 be roughh' classified as: (1) known physical and chemical agents; (2) 

 unknown constituents of blood-serum; (3) bacterial products; (4) 

 certain vegetable poisons; (5) snake venoms. 



^' Through usage this term has been limited to the sohition of the rod corpus- 

 cles, which is more accuratelv described hv the term crythron/toli/xis. For liihli- 

 ography see Sachs, Ergel)nisse der Pathol.", 1<»02 (7), 7i4; Ht'Oti (11), 515; Kolle 

 and Wassermann's Handbuch, 1913 (II), 793; Landsteiner, Handbuchd. Biochem., 

 1909 (II (D), 395. 



