THEORIES OF IMMUNITY. 



bacteriolysis, and they may be illustrated by 

 formulae similar to those already explained. 



Thus — cytolysis requires 



1. The cell to be acted upon, molecule=H-hX-|-X 



2. The immune body (produced by 



the previous injection of the 



above) moleeule=H-r-i?-fX 



3. The complement . . " =H+Ij+X 



And when the H groups have produced the 

 necessary combinations, the L atom group of 

 the complement may exert its lytic action. 



The production of the cytolytic property may, 

 of course, also be illustrated in the same way as 

 follows : 



Its production requires 



1. The foreign cell to be in- 



jected .... molecule=H+]^+X 



2. The tissue cells in which the 



injection is made, molecule=H+i/-f\X+X 



3. The complement . molecule=^T+LH-X. 



The same combinations are supposed to occur 

 in this as in preceding cases : the H atom-groups 

 combine together, so that those needed for proper 



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