132 IMMUNO-CATALYSIS 



a stereochemical conespondence with the antigen, as appears to be the 

 case from various studies, for the reason that its spatial configuration 

 has been oriented to fit the spatial configuration and the affinities of 

 the polar groups and of antigenic optical antipodes and space isomers, 

 it would appear reasonable to expect that the differences between anti- 

 bodies against 1- and d-antigens are sufficiently great to render them 

 antigenically distinguishable. At least it would seem that these anti- 

 bodies should spatially be sufficiently different to make them antigeni- 

 cally different from the normal globulins. 



Pauling's concept of the antibody molecule that "only in the con- 

 figuration of the chain, that is, in the way that the chain is coiled in 

 the molecule," could not, in our opinion, be viewed simply as a physical 

 change not involving a change in the spatial position of the atoms 

 or groups. For it is stated by Pauling that the atoms and groups which 

 form the surface of the antigen will attract certain complementary 

 parts (positively and negatively charged groups). This may imply 

 that various groups in the globulin molecule may undergo spatial 

 rearrangement as a consequence of the said polar property of groups to 

 yield a new configuration in the coiled chain end of the molecules. 



It would therefore appear that if a difference in the position of H 

 and OH in R-a-glucoside or R-a-galactoside antigens and those in 

 d- and 1-tartranilic acid antigens are capable of producing specific 

 antibodies, it is reasonable to ask why possible changes in the spatial 

 arrangement of the polar groups, NH2, COOH, OH, CONH, SH, 

 largely responsible for the chemical reactivity of the proteins, should 

 not be considered also as possible factors in the formation of anti- 

 antibodies against these antibodies. 



To obtain an answer to the question whether or not anti-antibodies 

 could be produced numerous investigations have been carried out since 

 the time of Ehrlich. The results, however, have not been of a defini- 

 tive nature to effect a clear cut differentiation between the antigenicity 

 of normal and antibody globulins derived from a given species of 

 animal. The reason for failure to do so apparently is to be found, 

 as recent studies have shown, in the fact that the antibody globulin 

 molecule is composed in part of an inactive portion which is in- 

 distinguishable from normal globulin. The only clear proof that 

 diphtheria antitoxic activity may be exhibited by a protein which is 

 antigenically distinct from normal globulin is provided by Northrop 



