VENOMS, TOXINS, ANTIBODIES 371 



some cases interpreted their observations in terms of direct effects of the 

 radiation on circulating immune substances. This interpretation hardly 

 seems justified in view of more recent work on the role of the reticulo-endo- 

 thelial system in immune phenomena, and the practical certainty that at 

 least some parts of this system will be affected by any type of irradiation. 

 Jaffe (92) has recently reviewed the relation between the reticulo-endo- 

 thelial or macrophage system and immune phenomena, and it need not 

 be further discussed here. The whole subject of irradiation in vivo is so 

 involved with the theories of immunity that it cannot be adequately con- 

 sidered here, but it is of such theoretical and therapeutic importance that 

 a cursory survey and bibliography are given. The latter is certainly far 

 from complete, but the nature of the evidence is such that no one paper 

 is of great importance: it is only by the agreement of many papers that 

 possibility becomes probability. It is probably not too much to say that 

 there is no single paper whose conclusions are based upon statistically 

 adequate data: most of them are pitiably inadequate. Under such 

 circumstances disagreement and confusion need cause no surprise. And 

 under such circumstances it does not seem worth while to assemble all 

 the available references, even though doubtless there have been experi- 

 ments along some lines which are here not touched upon. 



The different groups of immune bodies may best be considered here 

 about as above, except that the few references to toxins and antigens 

 will be treated in connection with their corresponding antibodies. 



ALEXIN 



There seem to have been practically no experiments on the effect of 

 visible light alone. Pincussen (132, page 415) refers briefly to unpub- 

 lished tentative experiments by Lippmann and himself on guinea pigs 

 with and without previous injection of eosin as a photodynamic sen- 

 sitizer. Without dye no effect was observed, but with dye the alexin 

 content of the serum decreased. 



Mixed visible and ultra-violet radiation was studied by Huntemiiller 

 (88) who exposed healthy persons to general irradiation from Jesionek 

 (quartz mercury) lamps long enough to cause moderate erythema. He 

 claims to have observed a transient increase, a subsidence, and a second- 

 ary increase to 2 to 3 times the normal alexin titer. The paper is 

 statistically very weak but derives some support from similar results 

 obtained previously by Koopman (100) with guinea pigs. Koopman also 

 noted an alexin decrease if irradiation was prolonged. 



As to X-rays, the results are conflicting. Quadrone (135, 136) in 

 two papers gives scantily supported evidence that weak daily doses lead 

 to alexin increase in man and experimental animals. This is supported 

 by Manoukhine's experiments (114, 115) upon which he based a theory of 

 the mechanism of immunity which is now not accepted. (See Manou- 

 khine, 116.) Manoukhine thought that X-rays caused leucocytolysis, 



