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Strain variation in Entamoeba histolytica

III. The influence of the bacterial flora on virulence to rats

Published online by Cambridge University Press:  06 April 2009

R. A. Neal
Affiliation:
The Wellcome Laboratories of Tropical Medicine, London

Extract

1. The total bacterial floras from invasive strains of Entamoeba histolytica, when added to non-invasive strains, do not increase the invasiveness of the latter.

2. The bacterial flora of non-invasive strains do not inhibit the invasiveness of virulent strains.

3. Bacteria from a virulent substrain (revived by serial liver passage) do not increase the invasiveness of the attenuated parent strain.

4. It is concluded that the virulence of a strain of E. histolytica is primarily dependent upon the invasiveness of the amoeba itself.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1956

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References

REFERENCES

Cleveland, L. R. & Sanders, E. P. (1930). The virulence of a pure line and several strains of Entamoeba histolytica for the liver of cats, and the relation of bacteria, cultivation and liver passage to virulence. Amer. J. Hyg. 12, 569.Google Scholar
DeLamater, J. N., Michaelson, J. B., Hallman, F. A. & Blumenthal, H. (1954). An investigation into hyaluronidase as a factor in the mechanism of tissue invasion by Endamoeba histolytica. Amer. J. trop. Med. Hyg. 3, 1.Google Scholar
Deschiens, R. (1938). Nouvelles données sur le rôle de la flore associée à l'amibe dysentérique dans l'amibiase expérimentale. C.R. Soc. Biol., Paris, 127, 1076.Google Scholar
Dobell, C. (with Neal, R. A. & Hoare, C. A.) (1952). Researches on the intestinal protozoa of monkeys and man. XII. Bacterial factors influencing the life history of Entamoeba histolytica in cultures. Parasitology, 42, 16.CrossRefGoogle ScholarPubMed
Dougherty, E. C. (1953). Problems of nomenclature for the growth of organisms of one species with and without associated organisms of another species. Parasitology, 42, 259.CrossRefGoogle ScholarPubMed
Frye, W. W. & Meleney, H. E. (1933). Studies of Endamoeba histolytica and other intestinal protozoa in Tennessee. VI. The influence of the bacterial flora in cultures of E. histolytica on the pathogenicity of the amoebae. Amer. J. Hyg. 18, 543.Google Scholar
Hargreaves, W. H. (1946). The treatment of amoebiasis with special reference to chronic amoebic dysentery. Quart. J. Med. 15, 1.Google Scholar
Luttermoser, G. W. & Phillips, B. P. (1952). Some effects of cultural associates on the infectivity of a strain of Endamoeba histolytica for the rabbit. Amer. J. trop. Med. Hyg. 1, 731.CrossRefGoogle ScholarPubMed
Meleney, H. E. & Frye, W. W. (1933). Studies of Endamoeba histolytica and other intestinal protozoa in Tennessee. V. A comparison of five strains of E. histolytica with reference to their pathogenicity for kittens. Amer. J. Hyg. 17, 637.Google Scholar
Nauss, R. W. & Rappaport, I. (1940). Studies on amoebiasis. I. Pathogenesis of mucosal penetration. Amer. J. trop. Med. 20, 107.CrossRefGoogle Scholar
Neal, R. A. (1951). Some observations on the variation of virulence and response to chemotherapy of strains of Entamoeba histolytica in rats. Trans. R. Soc. trop. Med. Hyg. 44, 439.CrossRefGoogle ScholarPubMed
Neal, R. A. (1952). Experimental production of pure mixed strains of Entamoeba histolytica. Parasitilogy, 42, 40.CrossRefGoogle ScholarPubMed
Neal, R. A. (1954). The influence of encystation upon the virulence of Entamoeba histolytica to rats. Trans. R. Soc. trop. Med. Hyg. 48, 533.CrossRefGoogle ScholarPubMed
Neal, R. A. & Vincent, P. (1955). Strain variation in Entamoeba histolytica. I. Correlation of invasiveness in rats with the clinical history and treatment of the experimental infections. Parasitology, 45, 152.CrossRefGoogle ScholarPubMed
Neal, R. A. & Vincent, P. (1956). Strain variation in Entamoeba histolytica. II. The effect of serial liver passage on the virulence. Parasitology, 46, 173.CrossRefGoogle ScholarPubMed
Okamoto, J. (1954). On the influence of Clostridium perfringens upon the experimental infection of Entamoeba histolytica in rats. Keio J. Med. 3, 121.Google Scholar
Phillips, B. P. & Bartgis, I. L. (1954). Effects of growth in vitro with selected microbial associates and of excystation and encystation, on the virulence of Endamoeha histolytica for guinea-pigs. Amer. J. trop. Med. Hyg. 3, 621.Google Scholar
Phillips, B. P., Wolfe, P. A., Rees, C. W., Gordon, H. A., Wright, W. H. & Reyniers, J. A. (1955). Studies on the ameba-bacteria relationship in amebiasis. Amer. J. trop. Med. Hyg. 4, 675.CrossRefGoogle ScholarPubMed
Spector, B. K. (1935). The pathological changes produced in the intestines of kittens by Endamoeba histolytica, with and without certain added bacteria. Amer. J. Hyg. 22, 366.Google Scholar
Stewart, G. T. & Jones, W. R. (1948). The pathology of an experimental amoebic infection in the rat. Ann. trop. Med. Parasit. 42, 33.Google Scholar