Dissemination of Encephalitozoon intestinalis, a causative agent of human microsporidiosis, in IFN‐γ receptor knockout mice

The dissemination of Encephalitozoonintestinalis, a microsporidium causing intestinal diseases and systemic infection in humans, was investigated in IFN‐γ R°/° mice. Although lesions were seen in organs of autopsied animals, the parasites were rarely detected using histological examination. Nevertheless, infection of the duodenum, liver, kidneys and lungs was demonstrated by polymerase chain reaction. This method also enabled the detection of the parasite in the brain and the heart. The development of E.intestinalis in RK13 cell cultures to which cell suspensions from liver, kidney, lung or brain of infected IFN‐γ R°/° mice were added, confirmed the spread of intestinal microsporidiosis to these organs. No dissemination was observed in wild‐type mice. These results confirm those of previous studies and emphasize the low morbidity of the infection in IFN‐γ R°/° mice and confirm the role of IFN‐γ in the control of E. intestinalis infection. These mice infected with E. intestinalis offer important information about this interesting and important parasitic disease of man and animals.