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FVB/N mice are highly resistant to primary infection with Nippostrongylus brasiliensis

Published online by Cambridge University Press:  07 January 2009

M. L. KNOTT ,
S. P. HOGAN ,
H. WANG ,
K. I. MATTHAEI  and
L. A. DENT
M. L. KNOTT
Affiliation:
School of Molecular and Biomedical Science, University of Adelaide, Adelaide, South Australia, 5005, Australia
S. P. HOGAN
Affiliation:
Cincinnati Children's Hospital Medical Center, Department of Allergy and Immunology, University of Cincinnati College of Medicine, Cincinnati, Ohio45229, USA
H. WANG
Affiliation:
School of Molecular and Biomedical Science, University of Adelaide, Adelaide, South Australia, 5005, Australia
K. I. MATTHAEI
Affiliation:
Division of Molecular Bioscience, John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory, Australia, 0200
L. A. DENT*
Affiliation:
School of Molecular and Biomedical Science, University of Adelaide, Adelaide, South Australia, 5005, Australia
*
*Corresponding author: School of Molecular and Biomedical Science, University of Adelaide, Adelaide, South Australia, 5005, Australia. Tel: +61 8 83034155. Fax: +61 8 8303 4362. E-mail: lindsay.dent@adelaide.edu.au
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Summary

Nippostrongylus brasiliensis larvae are particularly susceptible to immunological attack during the pre-lung stage of primary and secondary infections in mice. Whilst most of the common laboratory strains of mice are permissive hosts for the parasite, in this study we report for the first time, the strong resistance of naïve FVB/N mice to N. brasiliensis. Damage to larvae is evident within the first 24 h of infection and this may be critical to later larval development and reproductive success. Inflammatory responses in the skin, and larval escape from this tissue were comparable in susceptible CBA/Ca and resistant FVB/N mice, with most larvae exiting within 4 h of a primary infection. Lung larval burdens were also similar between strains, but larvae recovered from FVB/N mice were smaller and less motile. In FVB/N mice, larval colonization of the gut was impaired and worms produced very few eggs. However FVB/N mice did not show enhanced resistance to Heligmosomoides bakeri (also known as Heligmosomoides polygyrus), a nematode largely restricted to the gut. Damage done in the pre-lung or lung stages of infection with N. brasiliensis is likely to contribute to ongoing developmental and functional abnormalities, which are profoundly evident in the gut phase of infection.

Keywords

FVB/N mouseNippostrongylus brasiliensisHeligmosomoides bakeriHeligmosomoides polygyrusprimary resistance
Type
Research Article
Information
Parasitology , Volume 136 , Issue 1 , January 2009 , pp. 93 - 106
Copyright
Copyright © 2009 Cambridge University Press

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