Mar.3. I9I9 A Blood-Destroying Substance in A scaris Lumbricoides 255 



(4) There appears to be an inverse relation between the hemolytic 

 property of the fluid and the presence of oxyhemoglobin in it. Fluid 

 from fresh worms contains oxyhemoglobin and is nonhemolytic. When, 

 however, the worms are kept alive in vitro, the oxyhemoglobin dis- 

 appears from the fluid and can no longer be detected by spectro- 

 scopic examination one week after the worms have been removed from 

 the host. Meanwhile the fluid becomes hemolytic. Whether oxyhemo- 

 globin in itself is the sole factor in the inhibition of hemolysis or whether 

 other substances are involved which are associated with the oxyhemo- 

 globin and disappear simultaneously with it has not been determined. 



(5) Salt-solution extracts of the worms made by grinding up 4 to 10 

 gms. of the fresh body substance of the parasites and suspending it in 

 100 cc. of an 0.85 per cent solution of sodium chlorid are hemolytic 

 to the washed erythrocytes of swine and other mammals, the hemo- 

 lytic potency of the extracts varying directly within certain limits with 

 the duration of the extraction. The reaction is independent of the 

 acidity of the solution, since it is not impaired by neutralization. 



(6) Extracts of dried worms in an 0.85 per cent solution of sodium 

 chlorid are decidedly hemolytic to the red corpuscles of various animals. 



(7) Salt-solution extracts of the intestine of the worm are more destruc- 

 tive to blood corpuscles than extracts of the body wall, of the repro- 

 ductive organs, or of the entire worm. 



(8) The various salt-solution extracts also do not lose their hemo- 

 lytic properties on boiling. 



(9) The addition of blood serum to tubes containing a mixture of 

 red blood corpuscles and body fluid or extract of the worms usually 

 inhibits hemolysis. 



(10) The hemolytic property of the fluid and of extracts of the worms 

 can also be destroyed by the addition of a small quantity of laked blood. 



(11) Excretions of the worms absorbed by the solution of sodium 

 chlorid in which the parasites are kept in vitro are not hemolytic. 



CONCLUSIONS 



The failure to demonstrate hemolytic principles in the excretions of the 

 worms when kept in vitro appears to favor the view that the hemotoxic 

 substances of ascaris partake of the nature of endotoxins. There is also 

 to be considered the possibility that the death of a worm in the intestine 

 may be followed by a rapid disintegration of its tissues and the liberation 

 of toxic substances before it passes out of the body of the host. Tallqvist 

 (//), in fact, has shown in the case of another parasite (Dibothriocephalus 

 latus) that the toxic substances are liberated only when the worm disin- 

 tegrates, which affords a possible explanation why Dibothriocephalus 

 sometimes produces no ill effects on its host, whereas in other instances 

 a severe anemia is present. The fact that in some cases human beings 

 and other animals infested with ascarids remain in apparent good health 

 106543°— 19 3 



