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In vivo killing of Giardia trophozoites harbouring bacterial endosymbionts by intestinal Paneth cells: an ultrastructural study

Published online by Cambridge University Press:  19 October 2004

K. A. EL-SHEWY  and
R. A. EID
K. A. EL-SHEWY
Affiliation:
Microbiology and Parasitology Department, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
R. A. EID
Affiliation:
Electron Microscopy Center, Faculty of Sciences, Zagazig University, Egypt
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Abstract

To date Paneth cells have not previously been reported to kill Giardia trophozoites and other protozoa in vivo. Here we report the first evidence for in vivo killing of Giardia trophozoites by intestinal Paneth cells. Transmission electron microscopic (TEM) examination of duodenal specimens taken from naturally infected mice revealed that only Giardia trophozoites harbouring peripheral bacterial endosymbionts were destroyed and lysed in the vicinity of the activated Paneth cells. Additionally, intestinal epithelium was more affected by Giardia harbouring bacterial endosymbionts than Giardia with no endosymbionts. Our findings imply that the bacterial endosymbionts within Giardia trophozoites have a role in both host protective and pathological mechanisms, probably through altering the trophozoite antigencity. These observations might shed light on the diversity in infectivity and host specificity of Giardia species.

Keywords

endosymbiosisgiardiasiselectron microscopyPaneth cellsin vivo killingnaturally infected mice
Type
Research Article
Information
Parasitology , Volume 130 , Issue 3 , March 2005 , pp. 269 - 274
Copyright
2004 Cambridge University Press

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References

REFERENCES

ALEY, S. B., ZIMMERMAN, M., HETSKO, M., SELSTED, M. E. & GILLIN, F. D. ( 1994). Killing of Giardia lamblia by cryptdins and cationic neutrophils peptides. Infection and Immunity 62, 5397–5403.Google Scholar
AYABE, T., SATCHELL, D. P., WILLSON, C. L., PARKS, W. C., SELSTED, M. E. & OUELLETTE, A. J. ( 2000). Secretion of microbicidal α-defensins by intestinal Paneth cells in response to bacteria. Nature, Immunology 1, 113–138.CrossRefGoogle Scholar
DE-SOUZA, W. & MOTTA, M. C. ( 1999). Endosymbiosis in protozoa of Trypanosomatidae family. FEMS Microbiology Letters 173, 1–8.CrossRefGoogle Scholar
GLAUERT, A. M. ( 1980). Fixation, Dehydration and Embedding of Biological Specimens. 3rd Edn. North-Holland Publishing, Amsterdam.
JONES, D. E. & BEVINS, C. L. ( 1992). Paneth cells in the human small intestine express an antimicrobial peptide gene. Journal of Biological Chemistry 267, 23216–23225.Google Scholar
MARTIN, E., GANZ, T. & LEHRER, R. I. ( 1995). Defensins and other endogenous peptide antibiotics of vertebrates. Journal of Leukocyte Biology 58, 128–136.CrossRefGoogle Scholar
MENG, T. C., HETSKO, M. L. & GILLIN, F. D. ( 1993). Antigenic switching of TSA 417, a trophozoite surface protein, following of the life cycle of Giardia lamblia. Infection and Immunity 61, 5394–5397.Google Scholar
MEYER, E. A. ( 1990). Taxonomy and nomenclature. In Giardiasis ( ed. Meyer, E. A.), pp. 51–60. Elsevier, Amsterdam.
NEMANIC, P. C., OWEN, R. L., STEVENS, D. P. & MULLER, J. C. ( 1979). Ultrastructural observations on giardiasis in a mouse model. II. Endosymbiosis and organelle distribution in Giardia muris and Giardia lamblia. Journal of Infectious Diseases 140, 222–228.Google Scholar
OUELLETTE, A. J. & SELSTED, M. E. ( 1996). Paneth cell defensins: Endogenous peptide components of intestinal host defense. FASEB Journal 10, 1280–1289.CrossRefGoogle Scholar
ROBERTS-THOMSON, I. C., STEVENS, D. P. & MAHMMOUD, A. A. F. ( 1976). Giardia in mouse: an animal model. Gastroenterology 71, 57.Google Scholar
SELSTED, M. E., MILLER, S. I., HENSCHEN, A. H. & OUELLETTE, A. J. ( 1992). Enteric defensins: antibiotic peptide component of intestinal host defense. Journal of Cell Biology 118, 929–939.CrossRefGoogle Scholar