The Research Of Mechanism For NKT Cells In The Feto-maternal Immune Tolerance During The Implantation Window

Objective:To study the change of T cell in the endometrium during the period of implantation windows for embryo; Some cytokines like IFN-γ, IL-4 are secreted from NKT cell activated by antigenα-GalCer. We check and analyze whether they regulate the balance of immune in maternal endometrium, the relation between active natural killer T cell and the success of embryo implantation.Methods:1,Immunohistochemistry staining was used to observe the localization of T cell in the peri-implantation uterus in the implantation window;2,The ficoll was used to separate the peripheral blood mononuclear cells in blood of mouses;3,The groups was determined according to intraperitoneal injection of various concentrations of antigenα-GalCer on the 4d of pregnancy and then measured the expression of IL-4, IFN-γin the peripheral mononuclear blood cells and uterine decidua by RT-PCR;Results:1,The result of immunohistochemistry showed that there were few of CD3 expressed on the membrane of T cells which were existed in uterine endometrium on the first, second, third, fouth day of pregnancy, but increased in the fifth day and then decreased in the sixth day of pregnancy;2,After the intraperitoneal injection of antigenα-GalCer(0,10.3,20.6,41.2ug/ml) and compared with the control group, the levels of IFN-γmRNA in PMBC and uterine endometrium of the 10.3,20.6,41.2ug/ml groups were decreased significantly(P<0.05), but among the added antigenα-GalCer groups their levels had no changes significantly(P>0.05);3,The levels of IL-4 mRNA in PMBC of the 10.3,20.6,41.2ug/ml groups were decreased significantly(P<0.05), among the added antigenα-GalCer groups their levels had no changes significantly(P>0.05). But the levels of IL-4mRNA in uterine endometrium of the 20.6ug/ml group were increased significantly(P<0.05)and the other groups had no changes significantly(P>0.05);4,In PMBC the relative optical density of IFN-γ/IL-4 mRNA of the 20.6ug/ml group was increased significantly(P<0.05); On the contrary the relative optical density of IFN-γ/IL-4 mRNA of the 20.6ug/ml group in uterine endometrium was decreased significantly(P<0.05).Conclusions:1,The quantity of CD3 T cells is increased during the period of embryo implanting in material uterine endometrium and it showes that CD3 T cells are involved in regulating the immune balance of uterine micro environment;2,In the window of implantation the active NKT cells produce high level of IL-4 and promote the humoral immune response in uterine mucosa.3,In PMBC the active NKT cells regulate the Th1/Th2 of immune balance towards the Th1 immune response, but in the uterine endometrium they adujust the Th1/Th2 of immune balance towards the Th2 immune response and maintain the formation of feto-maternal immune tolerance in uterine endometrium.