TY - JOUR

T1 - Echinococcus multilocularis infection in the field vole (Microtus agrestis)an ecological model for studies on transmission dynamics

AU - Woolsey, Ian David

AU - Bune, Nethe Eva Touborg

AU - Jensen, Per Moestrup

AU - Deplazes, Peter

AU - Kapel, Christian Moliin Outzen

PY - 2015

Y1 - 2015

N2 - We propose a model involving the oral inoculation of Echinococcus multilocularis eggs in a vole species and examine the infection dynamics in a dose-response experiment. Defined doses, 100 (n = 8), 500 (n = 5) and 1000 (n = 5) of E. multilocularis eggs were used to inoculate Microtus agrestis. Four female C57BL/6j mice were inoculated with 1000 eggs as positive controls. The groups inoculated with 100 and 500 eggs exhibited significantly higher lesion numbers, and relatively smaller lesion size was observed in the 1000 dose group. Undetectable abortive lesions may be responsible for some form of resource limitation early in the infection, resulting in lower lesion counts and size in the 1000 dose group. The C57BL/6j mice exhibited significantly fewer lesions than M. agrestis. The feasibility of measuring corticosterone (which has been shown to downregulate Th1 cytokines) in rodent hair and tumour necrosis factor (TNF) production in spleen cells was demonstrated by a positive correlation between corticosterone levels and higher lesion counts and TNF production in C57BL/6j, respectively. These results suggest that M. agrestis is more prone to a Th2 immune response than C57BL/6j, which is associated with E. multilocularis susceptibility and may explain why the parasite develops more slowly in murine models. This is the first data to suggest that M. agrestis is capable of supporting E. multilocularis transmission and thus may be suited as a model to describe the infection dynamics in an intermediate host that affects transmission under natural conditions.

AB - We propose a model involving the oral inoculation of Echinococcus multilocularis eggs in a vole species and examine the infection dynamics in a dose-response experiment. Defined doses, 100 (n = 8), 500 (n = 5) and 1000 (n = 5) of E. multilocularis eggs were used to inoculate Microtus agrestis. Four female C57BL/6j mice were inoculated with 1000 eggs as positive controls. The groups inoculated with 100 and 500 eggs exhibited significantly higher lesion numbers, and relatively smaller lesion size was observed in the 1000 dose group. Undetectable abortive lesions may be responsible for some form of resource limitation early in the infection, resulting in lower lesion counts and size in the 1000 dose group. The C57BL/6j mice exhibited significantly fewer lesions than M. agrestis. The feasibility of measuring corticosterone (which has been shown to downregulate Th1 cytokines) in rodent hair and tumour necrosis factor (TNF) production in spleen cells was demonstrated by a positive correlation between corticosterone levels and higher lesion counts and TNF production in C57BL/6j, respectively. These results suggest that M. agrestis is more prone to a Th2 immune response than C57BL/6j, which is associated with E. multilocularis susceptibility and may explain why the parasite develops more slowly in murine models. This is the first data to suggest that M. agrestis is capable of supporting E. multilocularis transmission and thus may be suited as a model to describe the infection dynamics in an intermediate host that affects transmission under natural conditions.

KW - Corticosterone

KW - Echinococcus multilocularis

KW - Microtus agrestis

KW - TNF

U2 - 10.1007/s00436-015-4355-9

DO - 10.1007/s00436-015-4355-9

M3 - Journal article

C2 - 25663069

VL - 114

SP - 1703

EP - 1709

JO - Parasitology Research

JF - Parasitology Research

SN - 0932-0113

IS - 5

ER -