CHAPTER VIII 

 REPLICATION OF VIRUS PATTERN 



1. Structural Constitution of Viruses 



It is a generally accepted fact that viruses can be inactivated with- 

 out being deprived of their specific antigenicity. This suggests that 

 more delicate, unstable part of the structure is required for the virus 

 action than for the immunological activity. 



Since virus particles even in the coagulated state can combine with 

 their host cell, it is evident that the structure concerning the specific 

 combination can exhibit its effect even when the virus are in the folded 

 state. Such a structure may belong to the backbone structure of the 

 protein and may be concerned in the immunological activity of the 

 virus, whilst external, unstable groups which are revealed on the un- 

 folding may be involved in the action of the virus as the template. 



Such unstable groups may involve the repulsive force of the virus 

 against the host cell protoplasm in contrast to the stable structures 

 which may give rise to the specific combining force. On account of 

 the disappearance of the repulsive force following the folding of the 

 particle, thereby only the combining force being left to exhibit its effect, 

 the virus may be able to combine easily with the host cell. 



In the writer's theory (22), antibodies are produced in entirely the 

 same way as viruses. However, in antibodies fine structures corres- 

 ponding to those of antigens fail to be induced, only gross structures 

 complementary to the determinant grougs of antigens being produced, 

 so that antigens do not multiply as do viruses. In other words, anti- 

 gens and antibodies share in common with the gross structures, but 

 not with the fine structures. Accordingly, antigen and antibody can 

 combine with one another but the uncommon fine structures may re- 

 pulse mutually after the combination ; thus immunological reaction such 

 as precipitin reaction may follow. On the other hand, since parent 

 viruses and newly produced daughter viruses are identical even in fine 

 structures, they combine with one another as do antigen and antibody, 

 but without mutual repulsion, whereas virus and host cell share in 

 common with the gross structures, but not with the fine structures, so 

 that the relation between antigen and antibody is comparable -to that 

 between virus and host cell. 



In short, there are two kinds of structures in the virus, the one is 



