ACTION OF ADJUVANTS 



mutation will automatically be strongly favoured while 

 antigen at appropriate concentration persists in the body. 

 In this way we can picture a slow appearance of antibody in 

 an animal which, by normal methods, would fail to produce 

 any. The effect of the adjuvant is essentially to ensure that 

 antigenic determinants are being made accessible at a more 

 or less steady rate for a prolonged period. Each minor 

 mutation in the right direction is thereby persistently 

 favoured for survival, and, provided such mutations are 

 biologically possible, an appropriate antibody will eventually 

 be produced. 



A point of interest is that in some instances antibody pro- 

 duction is slight or absent in the lymph node draining the 

 area in which the antigen plus adjuvant is deposited but is 

 active in distant lymph nodes (Askonas and White, 1956). 

 (See chapter viii, section 7.) 



It may be desirable at this point to discuss the extent to 

 which modification of clonal patterns by somatic mutation 

 should be included as an essential part of antibody theory. 

 There is no biological objection that can be raised against 

 the occurrence of minor somatic mutations. Research on 

 various aspects of cancer makes it certain that such mutations 

 are constantly occurring in any population of cells which is 

 in a suitable situation for the appearance of the mutant to be 

 recognized. Law's work on the appearance of radio-resistant 

 or drug-resistant lines of malignant cells is the most striking 

 only because the experimental set-up is particularly well 

 designed to demonstrate the type of mutant which is 

 prospering. 



Similarly, the type of mutant we are postulating here is 

 also in a position to prosper excessively. If the right mutation 

 occurs the cell in question is, in the presence of the antigenic 

 determinant, given a major advantage in the struggle to 

 produce a larger clone of descendants than its congeners. 

 If our general hypothesis is correct, there is no escape from 

 the picture of the mesenchymal cells of the body as an 



6 81 BC 



