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Anthelmintic resistance: markers for resistance, or susceptibility?

Published online by Cambridge University Press:  09 September 2010

R. N. BEECH ,
P. SKUCE ,
D. J. BARTLEY ,
R. J. MARTIN ,
R. K. PRICHARD  and
J. S. GILLEARD
R. N. BEECH*
Affiliation:
Institute of Parasitology, Macdonald College, McGill University, Ste Anne de Bellevue, QC, H9X 3V9 Canada
P. SKUCE
Affiliation:
Parasitology Division, Moredun Research Institute, Penicuik, Midlothian, EH26 0PZ, UK
D. J. BARTLEY
Affiliation:
Parasitology Division, Moredun Research Institute, Penicuik, Midlothian, EH26 0PZ, UK
R. J. MARTIN
Affiliation:
Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
R. K. PRICHARD
Affiliation:
Institute of Parasitology, Macdonald College, McGill University, Ste Anne de Bellevue, QC, H9X 3V9 Canada
J. S. GILLEARD
Affiliation:
Department Comparative Biology and Experimental Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
*
*Corresponding author: Institute of Parasitology, Macdonald College, McGill University, Ste Anne de Bellevue, QC, H9X 3V9 Canada. Tel: + 514 398 7535. Fax: + 514 398 7857. E-mail: robin.beech@mcgill.ca
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Summary

The Consortium for Anthelmintic Resistance and Susceptibility (CARS) brings together researchers worldwide, with a focus of advancing knowledge of resistance and providing information on detection methods and treatment strategies. Advances in this field suggest mechanisms and features of resistance that are shared among different classes of anthelmintic. Benzimidazole resistance is characterized by specific amino acid substitutions in beta-tubulin. If present, these substitutions increase in frequency upon drug treatment and lead to treatment failure. In the laboratory, sequence substitutions in ion-channels can contribute to macrocyclic lactone resistance, but there is little evidence that they are significant in the field. Changes in gene expression are associated with resistance to several different classes of anthelmintic. Increased P-glycoprotein expression may prevent drug access to its site of action. Decreased expression of ion-channel subunits and the loss of specific receptors may remove the drug target. Tools for the identification and genetic analysis of parasitic nematodes and a new online database will help to coordinate research efforts in this area. Resistance may result from a loss of sensitivity as well as the appearance of resistance. A focus on the presence of anthelmintic susceptibility may be as important as the detection of resistance.

Keywords

anthelmintic resistancebenzimidazolemacrocyclic lactonelevamisolemonepantelligand-gated ion-channelP-glycoproteinbeta-tubulin
Type
Review Article
Information
Parasitology , Volume 138 , Issue 2 , February 2011 , pp. 160 - 174
Copyright
Copyright © Cambridge University Press 2010

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