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Researches on the Intestinal Protozoa of Monkeys and Man. I. General Introduction, and II. Description of the whole Life-History of Entamoeba histolytica in Cultures

Published online by Cambridge University Press:  06 April 2009

Clifford Dobell
Affiliation:
National Institute for Medical Research, London, N.W. 3.

Extract

A pure strain of Entamoeba histolytica has been isolated and cultivated, and an attempt has been made to study and describe its whole life-history in detail.

This strain (K. 28 c) was derived from the dysenteric dejecta of a kitten experimentally infected per os by means of typical cysts from the faeces of a monkey (Macacus sinicus). It has now been under continuous cultivation for about 20 months (220 serial subcultures), and its development in vitro has been uniform throughout.

Methods have been devised, and are here described, whereby any desired stage in the life-history of this strain—amoebae, cysts, and all intermediate stages (including encystation and excystation)—can be readily procured in vitro at will.

Detailed study has shown that the trophic amoebae multiply in cultures by simple binary fission only, as they do in their natural hosts. Their mode of division is briefly described.

Encystation also occurs in vitro just as it does in the bowel, with formation of characteristic precystic amoebae and the final production of typical quadrinucleate cysts.

Excystation has been carefully studied, and it has been found that a single quadrinucleate, amoeba escapes from each cyst through a minute perforation in its wall. An account is given of this remarkable process, which has not been described previously.

The 4-nucleate excysted (metacystic) amoeba has been found to produce a new generation of trophic forms by a complicated series of nuclear and cytoplasmic divisions, which are described in detail for the first time. The final result of this subdivision is the production of eight uninucleate amoebulae by each quadrinucleate amoeba hatched from a cyst.

These amoebulae are young trophic amoebae, and not gametes or conjugants. No sexual phenomena of any sort have been observed during the metacystic itages: and the life-history of E. histolytica, as visible in vitro, is thus wholly sexual.

A development similar to that here described in the case of Strain K. 28 c has been found to occur in many other cultivated strains of E. histolytica— including a strain isolated directly from man, and a human strain experiaentally implanted in a monkey (M. sinicus) and recovered therefrom in pure culture. There are therefore good reasons for concluding that the development were described is not abnormal, and that it is probably closely parallel to that which occurs naturally inside man.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1928

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References

REFERENCES

Boeck, W. C. and Drbohlav, J. (1925). The cultivation of Endamoeba histolytica. Amer. J. Hyg. 5, 371.Google Scholar
Dobell, C. (1919). The Amoebae living in Man: a Zoological Monograph. London.Google Scholar
Dobell, C. (1925). [Review of papers by Boeck and Drbohlav.] Trop. Dis. Bull. 22, 727.Google Scholar
Dobell, C. (1927). Further observations and experiments on the cultivation of Entamoeba histolytica from cysts. Parasitol. 19, 288.CrossRefGoogle Scholar
Dobell, C. and Laidlaw, P. P. (1926). The action of ipecacuanha alkaloids on Entamoeba histolytica and some other entozoic amoebae in culture. Parasitol. 18, 206.CrossRefGoogle Scholar
Dobell, C. and Laidlaw, P. P. (1926 a). On the cultivation of Entamoebahistolytica and some other entozoic amoebae. Parasitol. 18, 283.CrossRefGoogle Scholar
Dobell, C. and O'connor, F. W. (1921). The Intestinal Protozoa of Man. London.CrossRefGoogle Scholar
Forbes, H. O. (1896, 1897). A Hand-book to the Primates. 2 vols. London.Google Scholar
Jameson, A. P. (1927). The behaviour of Balantidium coli Malm, in cultures. Parasitol. 19, 411.Google Scholar
Report of the Medical Research Council for the Year 19241925. London: H.M.Stationery Office. 1925. [Published 22 Jan. 1926.] Pp. 31, 32.Google Scholar
Report of the Medical Research Council for the Year, for 19251926. London: H.M.Stationery Office., 1926. [Published Feb. 1927.] Pp. 35, 36.Google Scholar
Report of the Medical Research Council for the Year, for 19261927. London: H.M.Stationery Office., 1928. [Published in Jan.] Pp. 3335.Google Scholar
Boeck, W. C. and Drbohlav, J. (1925). The cultivation of Endamoeba histolytica. Amer. J. Hyg. 5, 371.Google Scholar
Chatton, E. (1917). L'éclosion des kystes et les premiers stades de l'évolution de l'amibe dysentérique humaine chez le chat. Bull. Soc. Path. Exot. 10, 834.Google Scholar
Cutler, D. W. (1918). A method for the cultivation of Entamoeba histolytica. J. Path, and Boot. 22, 18.Google Scholar
Cutler, D. W. (1919). Observations on Entamoeba histolytica. Parasitol. 11, 127.Google Scholar
Darling, S. T. (1913). Observations on the cysts of Entamoeba tetragena. Arch. Internal Med. 11, 1.CrossRefGoogle Scholar
Dobell, C. (1919). The Amoebae living in Man: A Zoological Monograph. London.Google Scholar
Dobell, C. (1927). Further observations and experiments on the cultivation of Entamoeba histolytica from cysts. Parasitol. 19, 288.CrossRefGoogle Scholar
Dobell, C. and Jepps, M. W. (1918). A study of the diverse races of Entamoeba histolytica distinguishable from one another by the dimensions of their cysts. Parasitol. 10, 320.CrossRefGoogle Scholar
Dobell, C. and Laidlaw, P. P. (1926). The action of ipecacuanha alkaloids on Entamoeba histolytica and some other entozoic amoebae in culture. Parasitol. 18, 206.CrossRefGoogle Scholar
Dobell, C. and Laidlaw, P. P. (1926 a). On the cultivation of Entamoeba histolytica and some other entozoic amoebae. Parasitol. 18, 283.Google Scholar
Hegner, R. (1927). Excystation in vitro of human intestinal protozoa. Science, 65, 577.CrossRefGoogle ScholarPubMed
Hollande, A. C. (1916). Coloration noire des coupes histologiques, par l'emploi du chlorocarmin à l'alun de fer. C.R. Soc. Biol. 79, 662.Google Scholar
Knowles, R. (1928). An Introduction to Medical Protozoology. Calcutta.Google Scholar
Kofoid, C. A. and Swezy, O. (1925). On the number of chromosomes and the type of mitosis in Endamoeba dysenteriae. Univ. California Publ. Zool. 26, 331.Google Scholar
Laidlaw, P. P., Dobell, C., and Bishop, A. (1928). Further experiments on the action of emetine in cultures of Entamoeba histolytica. Parasitol. 20, 207.Google Scholar
Penfold, W. J., Woodcock, H. M., and Drew, A. H. (1916). The excystation of Entamoeba histolytica (tetragena) as an indication of the vitality of the cysts. Brit. Med. J. 1, 714.CrossRefGoogle ScholarPubMed
Smith, S. C. (1927). Excystation in lodamoeba williamsi in vivo and in vitro. Science, 65, 69.Google Scholar
Smith, S. C. (1928). Host-parasite relations between lodamoeba williamsi and certain mammalian hosts (guinea pigs and rats). Amer. J. Hyg. 8, 1.Google Scholar
Uribe, C. (1926). Nuclear division in the trophozoites of Endamoeba histolytica. Proc. Nat. Acad. Sci. 12, 305.CrossRefGoogle ScholarPubMed
Walker, E. L. in: Walker, and Sellards, (1913). Experimental entamoebic dysentery. Philippine J. Sci.(B. Trop. Med.) 8, 253.Google Scholar
Wight, T. H. T. and Prince, L. H. (1927). Artifacts in endamoebae which have led to the naming of a new genus and species. Amer. J. Trop. Med. 7, 287.CrossRefGoogle Scholar
Wilson, C. W. (1916). On the life-history of a soil amoeba. Univ. California Publ. Zool. 16, 241.Google Scholar
Yorke, W. and Adams, A. R. D. (1926). Observations on Entamoeba histolytica. I. Development of cysts, excystation, and development of excysted amoebae, in vitro. Ann. Trop. Med. and Parasitol. 20, 279.Google Scholar
Yoshida, K. (1918). The encystment of dysentery amebae in vitro. J. Exp. Med. 28, 387.CrossRefGoogle ScholarPubMed
Yoshida, K. (1920). Reproduction in vitro of Entamoeba tetragena and Entamoeba coli from their cysts. J. Exp. Med. 32, 357.CrossRefGoogle ScholarPubMed