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Strain variation in Entamoeba histolytica

II. The effect of serial liver passage on the virulence

Published online by Cambridge University Press:  06 April 2009

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

Extract

1. Liver lesions were easily induced in hamsters with two strains of E. histolytica but not with six others.

2. Serial liver passage increased the invasiveness to the rat's caecum of one strain which had become attenuated by in vitro cultivation.

3. The invasiveness of one of the liver passage substrains was lost a second time after cultivation in vitro and a second series of liver passages restored some degree of virulence.

4. Serial liver passage did not increase the invasiveness of two avirulent strains.

5. The ease of production of amoebic liver lesions in hamsters is not correlated with invasiveness in the rat's caecum.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1956

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References

REFERENCES

Chang, S. L. (1945). Studies on Entamoeba histolytica. V. On the decrease in infectivity and pathogenicity for kittens of E. histolytica during prolonged in vitro cultivation and restoration of these characters following encystment and direct animal passage. J. infect. Dis. 76, 126.Google Scholar
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.CrossRefGoogle ScholarPubMed
Faust, E. C. & Swartzwelder, J. C. (1935). Effect of continuous passage of Endamoeba histolytica through experimental dogs. Proc. Soc. exp. Biol., N.Y., 32, 954.Google Scholar
Meleney, H. E. & Frye, W. W. (1937). The effect of direct animal passage on the pathogenicity of Endamoeba histolytica for kittens. Amer. J. Hyg. 25, 313.Google Scholar
Neal, R. A. (1951 a). 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.Google Scholar
Neal, R. A. (1951 b). The duration and epidemiological significance of Entamoeba histolytica infections in rats. Trans. R. Soc. trop. Med. Hyg. 45, 363.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.Google Scholar
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.Google Scholar
Reinertson, J. W. & Thompson, P. E. (1951). Experimental amoebic hepatitis in hamsters. Proc. Soc. exp. Biol., N.Y., 76, 518.CrossRefGoogle ScholarPubMed
Thompson, P. E., McCarthy, D. & Reinertson, J. W. (1954). Observations on the virulence of Endamoeba histolytica during prolonged subcultivation. Amer. J. Hyg. 59, 249.Google Scholar
Yoshimura, B. (1952). Experimental studies on the amoebic liver abscess. 1. Experimental amoebic liver abscess in rats. Keio J. Med. 1, 313.Google Scholar