ميزان كنيزاسيون ليستريا منو سيتوژنز در موش نژاد Balb/c هاپلوييد H-id و اثر آن بر سقط جنين و بافت رحم و پلاسنتاي آلوده

Sublethal Dose of Listeria monocytogenes in BALB/c Pregnant Mice and Placenta Tissue and Its Effects on Abortiom and Uterus

Background and Objectives: Listeria monocytogenes is a gram-positive facultative intracellular non spore forming bacillus and enters the body after ingestion of contaminated foods susch as milk products or vegetables. The epidemiologic studies were shown that this bacterium is the cause of abortion and abnormalities in human embryo. The immunological aspects of listeriosis was much more studied experimentally during pregnancy in mice ,hence in this experimental study it is required to study about the bacteriological and embryological and histological aspects of listeriosis during pregnancy in sensitive haploid mice to listeriosis to prove the effect of this bacterium to cause abortion and histological changes. Materials and methods: two groups of Inbred BALB/c gestating pregnant mice as case and control were injected intra-peritoneally with 200(iL of 1.2LogFCU/ml Listeria monocytogenes and normal salin in order.,then few mice from each group randomally were selected and scarified during 0-30days of pregnancy , the number and the place of placenta were counted in their fetus and compared with the number of embryos in fetus to determine the number of abortion. 35 of pregnant mice were cesarined in day 24 of pregnancy and the contaminated organs were determined and the embryos of full term and cesarined mice were studied for the uterus and placenta sections. Results: This study was shown that, the abortion in mice after injection of sub lethal dose of Listeria monocytogenes shows significant difference in comparison with control groups and there were Atrophy and congestion in layers of uterus and columnar epithelium changes to coboidal and glands were atrophy. Bacteria first contaminate the cells lining the central arterial canal of the placenta, demonstrating their fetal trophoblast origin, bacteria then disseminate rapidly to syncytiotrophoblast cells lining the villous core in the labyrinthine zone of placenta. Conclusion: In this study, the effect of L.monocytogenes on abortion was proved, so the role of effective factors on the abortion in the relation with listeriosis such as embryonic tissues and interaction of immunological response between different embryonic tissues during pregnancy has to be searched in future studies, our results suggest that the infection of murine placenta is dependent, at the early phase, on circulating bacteria and their interaction with endovascular trophoblastic cells.