The Research Of Mechanism For NKT Cells Effecting On C57BL/6 Mice Of Embryo Implantation And Development

Objective:To study NKT cell affecting embryo of C57BL/6 mice implantation and development, NKT cell is activated by antigen KRN7000,then we check some secreted cytokines(IL-10 and TNF-α)and analyze that they regulate the immune balance in maternal endometrium.Methods:1,After intraperitoneal injection of different concentrations of KRN7000 on different pregnancy time, the groups were observed embryo number and embryo development;2,After intraperitoneal injection of different concentrations of KRN7000 on different pregnancy time, the groups measured the expression of IL-10, TNF-a mRNA in uterine decidua by RT-PCR.Results:1,Intraperitoneal injection of different concentrations of antigen KRN7000 on the D3 and D6 of pregnancy mice respectively, by observing embryo number and their development on D8 of pregnancy,the results showed on the D3 of pregnancy administration, the experimental groups compared with the control group embryonic implantation number were significant differences (P<0.05), And on the D6-day administration, we found that the experimental groups induced embryo abortion, embryo abortion rate of 100%.2,After 24 hours intraperitoneal injection of different concentrations of antigen KRN7000 (0,1.25,2.5,5μg/ml) on the D3 and D6 of pregnancy mice respectively, it detected the expression of IL-10 mRNA by RT-PCR.The results showed compared with the control group, the expression levels of IL-10mRNA on D4 of uterine endometrium of the experimental groups decreased significantly(P<0.05), but among the experimental groups their levels had no changes significantly (P>0.05) compared with the control group, the levels of IL-lOmRNA on D7 of uterine endometrium of the experimental groups reduced significantly(P<0.05), but among the experimental groups their levels had no changes significantly (P>0.05)3,After 24 hours intraperitoneal injection of various concentrations of antigen KRN7000 (0,1.25,2.5,5μg/ml) on D3 and D6 of pregnancy mice respectively, it detected the levels of TNF-a mRNA by RT-PCR. The results showed the levels of TNF-a mRNA uterine endometrium of experimental groups on D4 of pregnancy decreased significanfly(P<0.05), among the experimental groups their levels had no changes significantly (P>0.05); The level of TNF-a mRNA on D7 of pregnancy uterine endometrium of the control group was lower than the experimental groups, their levels of 1.25μg/ml and 2.5μg/ml experimental groups increased significantly (P< 0.05),but 5μg/ml experimental groupdidn't increased significantly (P>0.05).4,By analysising the ratios of TNF-α/IL-10 mRNA relative optical density on D4 and D7 of pregnancy, the results showed that on D4 of pregnancy the ratio of TNF-a/IL-10 mRNA of the control group was lower than the experimental groups, the ratios of TNF-a/IL-10mRNA of the 1.25μg/ml and 5μg/ml groups raised significantly(P<0.05),while 2.5μg/ml group was in contrast. On D7 of pregnancy, the ratio of TNF-a/IL-10 mRNA of the control group decreased significantly(P< 0.05),among the experimental groups weren't significant difference (P>0.05).Conclusions:1,Before implantation of the embryo,there was role in reducing embryo number and development,while after implantation of the embryo, it induced embryo abortion;2,After implantation of the embryo, excessive expression of TNF-a induced embryo abortion;3,Th1/Th2 of immune balance was regulated towards the Thl immune response by the active NKT cell, it was bad for the formation of feto-maternal immune tolerance in uterine endometrium.