Author
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HARP, JAMES |
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Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 11/10/1997 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Cryptosporidium parvum is a significant cause of diarrheal disease in humans and economically important livestock species, especially young ruminants. There is no effective treatment available for this protozoan parasite. Mechanisms of intestinal colonization by C. parvum are not well understood. We used an infant mouse model of infection to examine whether carbohydrate interactions with a lectin-like or might regulate attachment of C. parvum to the intestinal surface. We found that sucrose, administered orally to mice at the time of challenge with C. parvum, greatly reduced infection from 3 to 9 days post-challenge. This effect was not seen with another disaccharide, maltose, nor with the monosaccharide constituents of sucrose, fructose and glucose. Preincubation of C. parvum oocysts prior to oral challenge of mice had no effect on infectivity of oocysts, thus sucrose was not directly toxic to the parasite. Histologic examination of intestinal section of mice treated with sucrose showed marked vacuolation of jejunal and ileal epithelium 1 day after treatment. Three days after treatment tissue appeared normal. The reduced susceptibility of mice to infection with C. parvum appears to be mediated by changes in the intestinal epithelium. These changes may include an alteration of surface receptors, or an osmotic effect that is induced by sucrose, but not other sugars tested. |
