NOVESIBER 21, 1902.] 



SCIENCE. 



815 



toxins with special affinities for certain 

 definite cells or substances of cellular origin 

 in the host. The contribution of the para- 

 sitic cells to these cytotoxins is the ambo- 

 ceptors. Either the parasite or the host 

 may provide the complements.* 



It may perhaps aid in grasping the ideas 

 here presented to imagine the bacteriiun, 

 in the capacity of the host, as a structure 

 so large that one could inject into it animal 

 cells. Provided the proper receptor ap- 

 paratus is present, the resulting reaction 

 on the part of the bacterium, as described, 

 would be a process of immunization against 

 the animal cells through the formation of 

 specific cellulieidal substances. In reality 

 it is only certain atomic complexes of cells 

 which are concerned in this immunizing 

 reaction, and in comparison with these 

 even the smallest bacterium is a gigantic 

 object. 



Looked at from the point of view of the 

 bacterium as well as from that of the ani- 

 mal host, according to the hypothesis ad- 

 vanced the struggle between the bacteria 

 and the body cells in infections may be 

 conceived as an immunizing contest in 

 which each participant is stimulated by its 

 opponent to the production of cytotoxins 

 hostile to the other, and thereby endeavors 

 to make itself immune against its antag- 

 onists. These mutually antagonistic cyto- 

 toxins are capable of injuring the parasitic 

 cells on the one hand or the body cells on 

 the other, only when escaping combination 

 outside of them they are anchored to the 

 receptors of the cells to which their respec- 

 tive affinities are adjusted. This combina- 

 tion with the cells, if it does not result in 

 too great injury to them, is the condition 

 for further production of the cytotoxic 



* We may thus speak of somatogenic cytotoxins 

 resulting from the action of bacterial stimuli on 

 cells of the host, and of baeteriogenie cytotoxins 

 from somatogenic stimuli, also of somatogenic 

 and baeteriogenie complements. 



intermediary bodies thi'ough over-produc- 

 tion and discharge of receptors.* The im- 



* It will be observed that these discharged re- 

 ceptors may be regarded as the equivalents of 

 anti-immime bodies. E. W. Ainley Walker, in 

 an interesting and suggestive paper on ' Immuni- 

 zation against Immune Serum ' [Journal of Path- 

 ology and Bacteriology, March, 1902), shows ex- 

 perimentally that bacteria growing in immune 

 serums produce anti-immune bodies, and thereby 

 become more ^drulent. He concludes that ' the 

 basis of bacterial virulence and of chemiotactlc 

 influence is identical, and constitutes that atom 

 group which causes the production of the immune 

 body.' My hypothesis includes the conceptions 

 supported by Walker, and also much more. Ac- 

 cording to the hypothesis, certain bacterial anti- 

 bodies are capable not only of neutralizing im- 

 mune bodies of the host, but with the aid of 

 complements also of poisoning the cells of the 

 host. It is not diflicult to imagine various condi- 

 tions in which the anti-bodies of bacterial origin 

 may escape neutralization before entering into 

 union with the host's cells. The substances which 

 stimulate bacteria to produce these antibodies 

 need not necessarily be toxic to them; in fact, 

 toxicity, such as that of strong bactericides of 

 cellular origin, would hinder their production. 

 The essential things are that the stimulating sub- 

 stances have the requisite combining groups for 

 bacterial receptors, and that the cast-off receptors 

 be complemented within the body of the host. Each 

 of the various baeteriogenie cytotoxins probably 

 contains a multitude of partial amboceptors, with 

 varying cytophilic and complementcphilic affini- 

 ties, in accordance with the views cf Ehrlieh and 

 Morgenroth. It is self-evident that through a 

 mechanism similar to that described parasites 

 within the infected body may be stimulated by 

 atom groups derived from the host to the produc- 

 tion also of antibodies other than cytotoxins, such 

 as various agglutinins, precipitins, antienzymes, 

 and perhaps of uniceptors of the nature of secreted 

 soluble toxins, or of enzymes, all adjusted against 

 the host. Questions relating to the source and 

 nature of the complements, particularly of intra- 

 cellular complements, and also to anticomple- 

 ments, are manifestly of importance in relation 

 to the hypothesis, but it would complicate the 

 subject too much to discuss these and other rnat- 

 ters here, where my purpose is merely to outline 

 the essential features of this new theory of infec- 

 tion with reference to the particular points under 

 consideration. 



