VENOMS, TOXINS, ANTIBODIES 365 



With ultra-violet light the situation is much clearer. It has already 

 been noted that when a serum containing both alexin and a hemolysin 

 is irradiated, the alexin is destroyed first (Delbet and Beauvy, 41; and 

 Diacono, 43). This corresponds to the relatively high thermostability 

 of hemolysin, and appears to be borne out by comparisons of the photo- 

 sensitivity of the two principles taken separately. This was first pointed 

 out by Baroni and Jonesco-Mihaiesti (13) and confirmed by Stiner and 

 Abelin's two papers, one (1) on alexin and the second (154) on ambo- 

 ceptor (hemolysin). 



They found that, as might be expected, it took longer to completely 

 inactivate hemolysins of high titer, and that diluted sera were more 

 quickly rendered ineffective. So long as "complete" destruction is 

 used as an end point, so long will it be impossible to say whether such 

 experiments do or do not indicate differences in sensitivity to irradiation : 

 they may mean only that it takes longer to reach a given low level of 

 titer from a high start than from some intermediate level. We cannot 

 even be sure that alexin is more sensitive to light than are hemolysins. 

 Reaction-rate constants (see page 359) or even the relative times required 

 for a given fractional reduction in titer, say, to one-half, would have 

 given this much needed information. We now stand on most uncertain 

 ground. 



Stiner and Abelin also found that the normal hemolysins of human 

 blood were inactivated by ultra-violet light. Inactivation was again 

 complete sooner than for the specific hemolysins, but whether because 

 of greater lability or because of lower titer, it is impossible to say. Scott 

 (145, 146) was the first after Baroni and Jonesco-Mihaiesti to observe 

 inactivation of hemolysins by ultra-violet irradiation. Heuer (85) adds 

 nothing new, and Hassko (76) appears in this connection to have merely 

 confirmed Stiner and Abelin's findings. 



Friedberger (66), in additional experiments like Stiner and Abelin's, 

 also tested the effect of ultra-violet radiation on hemolysin fractions 

 analogous to those obtained from alexin-containing sera. As in the case 

 of alexin, the albumen fraction (E piece of alexin) was stabile, while the 

 globulin fraction (M piece of alexin) was destroyed by 20 min. irradiation. 

 This suggestive finding has never been made the basis for further work so 

 far as the literature shows, although some further details are given by 

 Friedberger and Scimone (67). 



As with alexin. X-ray experiments on hemolysins are inconclusive. 

 Negative results are reported by Fiorini and Zironi (58, 59), Scaffidi 

 (140), and Konrich (99). Fiorini and Zironi state only the dosage used: 

 5 to lOX; Scaffidi gives almost no information as to the source used; 

 Konrich fails to state voltage. Lusztig (HI) reported about % inactiva- 

 tion by 3 H.E.D., but in view of the findings of Baermann and Linser (10) 



