Correlation Study Of FFn And Spontaneous Preterm Birth

BackgroundPreterm birth (PTB) is estimated to account for6-10%of all births worldwide with13million PTBs occurring annually and1million resulting in death. The diagnosis of spontaneous preterm labor and accurate prediction of preterm delivery is notoriously difficult[1’2]. Preterm labor and delivery continues to be an unsolved puzzle in obstetrics. Preterm birth accounts for75%of perinatal deaths and more than50%of long-term neurological disabilities[3]. It is a major determinant of neonatal mortality and morbidity and has longterm adverse consequences for health. The frequency of preterm births is increasing worldwide, due to the use of assisted reproductive techniques coupled with the increasing frequency of multiple pregnancies. Advances in perinatal medicine have not reduced PTBs and effective measures that improve outcome are yet to be established. Identification of effective risk assessment can potentially improve outcomes by enabling targeted therapy while allowing efficient use of resources and avoiding unnecessary interventions. fFN testing is readily available, relatively cheap and easily applicable in a clinical setting.Fetal fibronectin (fFN) is diffusely distributed in fetal membrane, from amnion to decidua, providing structural support and adhesion of the fetal membranes to the uterine lining. In normal conditions, fFN is found at very low levels in cervico-vaginal secretions during the first22weeks of pregnancy, and it vanishes between22and35weeks’ gestation. Levels of fFN greater than or equal to50ng/mL at or after22weeks have been associated with an increased risk of spontaneous preterm birth, since it represents disruption of the chorio-decidual surface, leading to spontaneous preterm birth. A number of clinical trials have been conducted to study the association between cervico-vaginal fFN and the risk of PTB. fFN is probably plays an important role of regulation in the pathogenesis of sPTB. However, the pathological function of fFN in preterm labor is largely unknown, as relevant research is rare. Thus, the current study was aimed to explore the function of fFN in the molecule pathogenesis of sPTB to provide new ideas and methods for the prediction and therapy of sPTB.ObjectiveTo investigate the expression and significance of fFN、MMP-9、COX-2in placenta of patients with spontaneous preterm delivery and analyze the relationship between MMP-9and COX-2.Research the molecule function in the pathogenesis of sPTB.Methods1Expression and clinical significance of fFN,COX-2, MMP-9in spontaneous preterm delivery.Ninety women hospitalized in department of gynecology and obstetrics of Xijing Hospital from December2012to June2013were enrolled in the study, and they were divided into three groups:women with spontaneous preterm delivery (30cases), normal natural birth women(30cases) and cesarean delivery women as control group(30cases). fFN, MMP-9and COX-2in placenta of them were detected with immunohistochemistry, RT-PCR and Western blot.2Isolation and Culture of Human Trophoblast cellCollect placenta samples respectively from term labors and spontaneous preterm labors, and use trypsin cultivation to culture primary cytotrophoblast cells. Immunofluorescence was applied to identify cytotrophoblast cells.3The expression of MMP-9and COX-2in trophoblast under fFN.Use gelatin affinity chromatography to extract fFN from collected placenta issues. Cultured trophoblast cells were treated with fFN. The effect of fFN on MMP-9and COX-2was assessed by ELISA.Results1. The mainly positive expression of fFN, MMP-9and COX-2were found in cytoplasm of chorionic cells. The expression levers of fFN(100%), MMP-9(90%) and COX-2(93.3%) in spontaneous preterm group were higher than normal natural birth women group(fFN76.7%, MMP-980%, COX-246.7%) and cesarean delivery women group(fFN56.7%, MMP-946.7%, COX-250%)(P<0.05). The expression levers of fFN, MMP-9and COX-2in normal natural birth women group were higher than cesarean delivery women group (P<0.05).2. The purity of trophoblast cells was greater than90%in cultured cells, which means the cultured cells met the requirements of subsequent experiments.3. With the fFN treatment, the expression levels of MMP-9and COX-2were all upregulated in both PTB and TB trophoblast cells, compared with fFN-undisposed groups, and the differences of expression levels were statistically significant. Comparisons of the expression levels of MMP-9and COX-2between PTB and TB trophoblast cells showed no statistical significance.ConclusionIn summary, the expression levels of fFN, MMP-9, COX-2were all upregulated in PTB patients, implying that the fFN is not only a marker of preterm delivery, but plays a significant role in the pathogenesis of preterm labor.