Nov. 19. 1921 Hemotoxins from Parasitic Worms 387 



presence of these substances in the parasite is due to its blood sucking habit, basing 

 his assertion on the fact that blood serum contains neutral fats, fatty acids, and soaps. 

 This writer found a lipolytic enzym in worms of the genus Strongylus which apparently 

 converts the storage fat into fatty acid. It is of interest to note also that Bondouy 

 found neither lecithin nor cholesterin in the parasite. Lecithin, as is known, has the 

 property of activating certain hemolytic agents, namely, snake venoms, whereas 

 cholesterin inhibits hemolysis of blood by active hemolysins. Contrary to Weinberg's 

 experience (Weinberg, igoy), Bondouy found that Strongylus hemolysin is soluble in 

 alcohol. From the alcohol-soluble fraction of the parasite this writer isolated an 

 extremely active hemolysin which he identified as an alkaloid. He also found a 

 ptomain in the parasites which exhibited hemolytic properties. 



Brumpt and Joyeux (quoted by Brumpt, ipio) found that a watery extract of the 

 stomach worm of sheep (Haemonchus contortus) produced a slight hemolytic effect ^ 

 after 2}^ hours and a total hemolysis after 12 hours. Cuill6, Marotel, and Panisset 

 (iQii) state that extracts of sheep strongyles (species, of which apparently several 

 were involved, not given) did not exert any effect on sheep red blood corpuscles from 

 either healthy or sick animals. These writers also state that extracts of these parasites 

 contained hemoglobin. 



According to Garin {1913) Graphidium sirigosum and Trichostrongylus retortaeformis, 

 nematodes parasitic in the stomachs of hares and rabbits, secrete hemolysins. With 

 reference to the hemolysin of G. strigosuvi, Garin found that it is secreted by the living 

 worm in vitro. He found, furthermore, that the hemolysin is apparently a complex 

 substance and acts on the blood not directly but in combination with complement. 

 Heating at 55° C. for 30 minutes does not destroy but merely inactivates the hemolysin, 

 which may be reactivated by normal serum, according to this investigator. In view 

 of the limited number of experiments which Garin performed, his conclusions can be 

 accepted anly with reservation. The work requires confirmation. As for the hemoly- 

 sin from T. retortaeformis, Garin found it to be far less potent than that of G. sirigo- 

 sum. He also states that the hemolysins from the two species have far greater affinity 

 for the blood cells of rabbits than for those of other species of animals and are therefore 

 relatively specific. 



Yagi {1910) found that salt-solution extracts of the blood fluke. Schistosoma japoni- 

 cum, are hemolytic to erythrocytes of cattle, sheep, and rabbits. He found, fiuther- 

 more, that this hemolysin is soluble in ether and concluded that it is probably a fatty 

 acid. Yoshimura (191 3) experimented with salt-solution extracts of the same species 

 and found them to be destructive to rabbit erythrocytes. Human blood cells, accord- 

 ing to this writer, are refractory to these extracts. Yoshimura also experimented 

 with ether extracts, which he found destructive to rabbit red blood corpuscles and 

 to a lesser extent destructive to human red blood corpuscles. 



According to Guerrini (1908), Fasciola hepaiica secretes a hemolysin which is ab- 

 sorbed by the host and is demonstrable in the blood serum of the latter. 



Alessandrini (1913) records the results of experiments with extracts of Macracantho- 

 rhynchus hirudinaceus, the thorn-headed worm of the hog. He tested the body fluid 

 and extracts of various parts of the worm and found them to be destructive to the red 

 blood cells of swine, cattle, and sheep. Alessandrini states that the hemolysin from 

 M. hirudinaceus is a colloidal substance insoluble in alcohol, soluble in water, and highly 

 sensitive to heat, since a temperature of 40° C. diminished its potency and a tempera- 

 ture of 515° destroyed it entirely. 



Although the larvae of species of Gastrophilus which occur in the stomach of the 

 horse are in a zoological sense not parasitic worms, the results of a study of their toxic 

 secretions may be included in this review because these larval parasites are biologically 

 more closely related to parasitic worms than they are to free-living insect larvae. At 

 any rate their secretions may be absorbed by the host and give rise to disturbances 



• No details are given as to kind and quantity of blood corouscles used. 



