The Research Of Th17and Treg Cells Related Transcription Factor And Cytokines In The Peripheral Blood With RSA Patients

Recurrent spontaneous abortion (RSA) which is defined as two or more consecutive pregnancy losses is one of the common complications of pregnancy. It is reported that the incidence of RSA is0.4%～1.0%, accounting for15%～20%of the total abortions and occurs in approximately1%～5%of women at reproductive age. RSA has the performance of abdominal pain and postmenopausal vaginal bleeding.The reason of RSA is complex,many known causes of RSA including anatomical factors、endocrine disorders、structure and function abnormalities of chromosome、the infection of reproductive system and immunological factors.At present,about40%-60%of the RSA reason is unknown,most may be caused by the dyregulation of the maternal-fetal immune.In recent years,with the rapid development of immunology,it is found that the occurrence of RSA is closely related with immune factors.Recently, the immunological mechanisms with RSA are focused on regulatory T cells and Th17cells. The main source of Treg cell is the thymus tissue and the ratio of it in peripheral is about5%～～10%. Regulatory T cells have an immunosuppressive function, low multiplication capacity. They can inhibit potentially inflammation self-reactive T cells by identification of autoantigens, control the intensity of immune response, reduce the damage of tissue and maintain the stability of autoimmunity. Because of the important roles in autoimmune diseases, transplantation tolerance, tumor immunity and the maternal-fetal immune. So the research of regulatory T cells is of widely concerned.The Treg cells have two typical function features:one of it is immune inability, the other is immune suppression.The former refers to the use of various types of antigenic stimulation can not cause proliferation, the latter refers to it is not only can inhibit the immune effecter cell of the CD4+Tcells、CD8+Tcells、 NKT cell’s proliferation and activation but also can restrain B cells、macrophages and DC’s function. These two characteristics of Treg cells play a different role in different disease, raise of it can prevent autoimmune diseases, relieve inhibition rejection. Reduce of it can lower the immune surveillance.Fork head/winged helix transcription factor (Foxp3) which belongs to the fox head factor family is widely recognized as the CD4+CD25+Treg’s specific molecular markers and plays a key role in its differentiation and development function. Foxp3gene is located on human chromosome xp11.23-xp13.3, containing11exons and is highly conserved in human.The Th17cells are found in the study of collagen-induced arthritis (CIA) and experimental autoimmune encephalomyelitis (EAE). The traditional ideas believe that these two diseases belong to autoimmune disease and are mediated by the type of Thl cells.But then according to the research of CIA, it is found that clear IL-17or inject with antibody of IL-17can relieve the arthritis reaction in mice, while the mice with high expression of IL-17is aggravated. Therefore, the concept of Th17cells are proposed. Because it is from the initial CD4+Tcell’s differentiation and development, it can proliferation independently and secret IL-17, so named Th17.Retinoid-related orphan nuclear receptor (RORyt) is the key transcription factor that control the differentiation of Th17cells. RORyt can induce the gene which can encode IL-17A and IL-17F cytokine to express. Initial CD4+Tcells can be differentiated into middle cell with the same expression of RORyt and Foxp3,the differentiation direction depends on the peripheral existing cytokines. TGF-β can induce initial CD4+Tcells to differentiate into Treg cells, while added IL-6can block the path, prompting Th17/Treg cells differentiation to Th17cells. Thus, IL-6plays a critical role in the direction of the original T cell differentiation. IL-17has a variety of biological activity which can induce neutrophils’s proliferation, chemokines and mature, induce the protein expression of the vascular endothelial growth factor and momocyte chemotactic cell,promote multiple types of cell to secret TNF-a、IL-1、IL-8. In the research of human autoimmune diseases, it is found that the level of IL-17has upregulated to a certain extent in rheumatoid arthritis multiply sclerosis、inflammatory bowel disease、SLE.In conclusion, it is not difficult to find that regulatory T cells and its transcription factor of Foxp3, Th17cells and its transcription factor RORyt and also the related cytokines----IL-6、IL-17、TGF-β play an important role in the occurrence、 development of RSA. Base on this, we design the following experiment.ObjectiveTo analyze the level of Th17and Treg’s Specific transcription factor(RORyt and Foxp3) mRNA in the peripheral blood and detect the levels of IL-6、IL-17and TGF-β in the plasma of patients with RSA, in order to explore the role of Th17and Treg cells in the pathogenesis of RSA patients.Materials and MethodsA total of50RSA patients from the department of obstetrics and gynecology at the third affiliated hospital of zheng zhou university from December2011to Apirl2012were involved in our study. Meanwhile, we selected50normal early healthy pregnant woman as controls, the levels of RORyt mRNA and Foxp3mRNA were measured by Real-time fluorescent quantitative PCR. and analyzed the relationship between them; the expression of Serum cytokines were examined with ELISA.Statistical method:Statistical analysis was done using SPSS17.0. The statistical analysis of cuont data are ordinal variables using the line list data analysis, and then analyze the correlation; measurement data are expressed as mean±standard deviation. Different groups were compared using analysis of variance. Significant level being0.05. Results1. The expression of RORyt mRNA was obviously increased compared to healthy controls [(25.358±9.236) vs(10.611±5.792)]; the expression of Foxp3mRNA was decreased compared to healthy controls[(6.851±2.875) vs(32.218±5.023)].2. The expression of RORyt mRNA was negatively correlated with the expression of Foxp3mRNA in RSA patients (r=-0.530, P=0.018)3. The level of IL-6[(82.7±23.2) vs (210.4±40.6)] and TGF-β1[(269.3±29.6) vs (497.8±54.6)] in RSA patients was lower than the normal controls, but the IL-17[(172.8±33.9) vs (53.4±10.8)] in RSA patients was higher than the normal controls, they were significantly changed between the two groups.Conclusions1. The RORyt and Foxp3mRNA of Th17and Treg have crucial roles in the maintenance of immune homeostasis; The imbalance of Th17and Treg’s immune regulation produced by interaction between RORyt mRNA and Foxp3mRNA may take part in the pathogenesis of RSA, up-regulated the lever of RORyt mRNA and down-regulated the lever of Foxp3mRNA will lead to the imbalance of Th17and Treg which is an important cause of the RSA.2. The disorder of IL-6、IL-17、TGF-β1may also be important in the pathogenesis of RSA patients.