The Change Of Paneth Cells In The Toxoplasmosis Of Kunming Mice

To study the roles of intestinal Paneth cells in toxoplasmosis in mice,and the mechanism of Toxoplasma gondii oocysts invading the body,healthy Kunming mice were used as the object for this experiment.104 Toxoplasma gondii oocysts were fed by the experimental mice freely,to create the model of toxoplasmosis in Kuming mice.After administration 1d,3d,5d,6d respectively,clinical symptoms and lesions were observed.Duodenum,jejunum,ileum,and the large of intestine were taken and fixed.Using H&E and immunohistochemical staining method to examine intestinal lesions,the distribution and quantity of T.gindii,the change of the quantity of Paneth cells,granules and lysozyme in the small intestine.The main findings were as follows:1?After mice fed oocysts,their mesenteric lymph node smears were positive for T.gondii.5 days after inoculation(DAI),messy hair,arched,extreme weight loss and death were appeared.Histopathological of experimental group showed obvious enteritis,indicating it is success of the Kunming mice model of acute toxoplasmosis.2?Histopathological changes: No significant pathological changes in the 1 DAI.3 DAI,visible thickening of ileal lamina propria infiltrating lymphocytes.Hyperemia and mild inflammation could be seen at the villus of ileum especially the distal ileum.Paneth cells in the bottom intestinal crypt increased significantly,eosinophilic granular at the top of paneth cells were rich.5 DAI,lymphoid cells in the intestinal follicles were severely necrotic,lamina propria was significant thickening,the capillaries in the lamina propria were serious hyperemia.Intestinal glands in the ileum especially the back of the ileum were severely damaged.Villus was atrophic and necrotic.Chorioepithelium were found with degeneration,and vacuoles structure could be seen in the cytoplasm.Paneth cells at the base of the ileum gland of Most mice were decreased significantly.Granules in the survive PCs became smaller.Duodenal lamina propria was thickening,lymphocytes were proliferative.6 DAI,the inherent structure was disappeared in the ileum especially the back of the ileum.Duodenum and jejunum showed villus epithelial necrosis,hemorrhage in the lamina propria and lymphocyte proliferation.Paneth cells were lost.Intestinal glands were destroyed,Mucosal cells in the large intestine were necrosis,lamina propria wasthickening and lymphocytes infiltrate.HI scoring results showed 5-6 DAI the intestinal tissue injury significantly worse than the first three days.3?The results of the changes in crypt,Paneth cells and their granules: the total number of crypts,crypts containing PCs,PCs in the intestine cross-section,granules of cross section,PCs of single crypt and granules in a single PC showed the trend of increased first and decreased later,highest peak performance at 3 DAI,and lowest at6 DAI,with significant difference(p<0.05)compared to the control grouph,especially the distal ileum.4?The results of immunohistochemical staining showed that as the infection time gone on,the positive area of toxoplasma in the small intestine increasing,with the highest at 6 DAI which compared with 1 DAI or 3 DAI was significant difference(p<0.05).The number of T.gondii in the ileum was more than the other intestine.The 1th and 3 DAI after infection,single or multiple parasites could be seen distributed in the villi and lamina propria of the ileum.5 DAI and 6 DAI,positive parasites or excretions into a groph or tracts distributed in various locations,including the mucosa,submucosa and muscular.The number of the parasites in the mucosa was the largest with the more than submucosa.There were parasites invasion in the muscular,but the damage was not serious.5?As the infection time gone on,the positive area of lysozyme in the small intestine was increasing first and decreasing later,the peak was at 3 DAI and lower point at 5 DAI and 6 DAI.The positive area of the distal ileum at 5 DAI was significant difference compared with the control.The other experimental groups were not significant compared with the control group.Conclusion: In this study,we have successfully established Kunming mice toxoplasmasis model through fed toxoplasma oocysts roally.The results that the quantity of paneth cells and their granules were dynamic and eventually disappeared with the extension of infection time,indicating that T.gondii oocysts feeding Kunming mice had a significant influence on intestine paneth cells,which providing a theoretical basis for further research of the mechanism of roles of paneth cell loss in toxoplasmosis pathogenesis,also providing an experimental basis for the prevention and treatment of the small intestine paneth cell-based toxoplasmosis.