THE CELLULAR MECHANISMS OF DEFENCE 1029 



nevertheless may multiply on the surface of the body or in an abscess cavity 

 and lead to the death of the host, in consequence of the production by the 

 bacteria of soluble toxins which are absorbed into the blood-stream. 

 Examples of such micro-organisms are those which are associated with 

 tetanus and diphtheria. The process of intracellular digestion is obviously 

 inadequate to deal with such cases, and since we have the power of resisting 

 and recovering from these diseases there must be other mechanisms at the 

 disposal of the body for the neutralisation of these toxins. The protec- 

 tion of the body against destruction by bacterial toxins involves in fact 

 a whole series of chemical mechanisms which we must regard as of equal 

 importance and as co-operating with the phagocytic mechanism. 



