| Background and ObjectiveThe incidence of preterm delivery in the world is 5%~18%.Preterm delivery is divided into spontaneous preterm birth,preterm premature rupture of membranes and iatrogenic preterm labor.Spontaneous preterm birth can cause 60% preterm delivery and is the leading cause of neonatal morbidity and mortality.Although there has been a large number of basic and clinical studies on the prevention and treatment of preterm delivery,the rate of preterm birth is still high.Evidence have shown that histologic chorioamnionitis(HCA)is closely related to the occurrence of spontaneous preterm labor.HCA is not equivalent to intrauterine infection,which is caused by microbial invasion or the release of "dangerous signals".HCA had no obvious clinical symptom,is closely associated with adverse neonatal outcomes and is significantly correlated with gestational age: the smaller gestational age is,the greater probability of occurrence.Dangerous signal factors have been identified,including heat shock protein(HSP70).HSP70 is a kind of highly conserved protein expressed widely in the nature.HSP70 was induced by ischemia,hypoxia,high temperature,infection and other stimulation.HSP70 regulate intracellular processes to maintain homeostasis during cell proliferation/differentiation and thus,function as molecular chaperines.Recent studies suggest exracellular HSP70 participate in the innate and adaptive immune response.In this research,the relative expression of HSP70 in fetal membrane and the levels of HSP70 in maternal peripheral blood and umblical cord blood were tested to realize the relationship with spontaneous preterm birth with or without HCA.Materials and Methods 1.Study object63 cases of pregnant women with spontaneous preterm labor were recruited from June 2015 to January 2017 in the Third Affiliated Hospital of Zhengzhou University: 26 cases with HCA(preterm delivery with HCA group)and 37 cases without HCA(preterm delivery without HCA group);32 cases with normal pregnancy who delivered normal infants at term(normal group).2.Methods(1)The location and positive expression rate of HSP70 protein in fetal membrane was detected by immunohistochemistry;(2)The expression of HSP70 mRNA in fetal membrane was detected by real time quantitative-polymerase chain reaction;(3)The expression of HSP70 protein in fetal membrane was detected by western blot;(4)The levels of HSP70 in maternal peripheral blood and umbilical cord blood was detected by enzyme linked immunosorbent assay;(5)The perinatal outcomes were compared among the three groups.3.Statistical analysisData analysis were performed by SPSS,version 21.0.The quantitative data were expressed as the means±SD.For multiple quantitative data,a one-way ANOVA or non-parametric Kruskal-Wallis test was performed.Count data expressed in percentage.For categorical variables,the ?2 test was used.Correlation analysis using Pearson test.Significant level ?=0.05.The comparision between two groups,significant level ??=?/comparision times=0.0167.Results 1.Comparison of maternal general situationComparison of the delivery gestational age,preterm delivery with HCA group and preterm delivery without HCA group were less than the normal group(P<0.01).The rest general situation were no significant difference among the three groups(P>0.05).2.The location and positive expression rate of HSP70 protein in fetal membraneHSP70 is expressed in the cytoplasm and cytomembrane of chorionic and amniotic epithelial cells.The positive expression rate of HSP70 protein in fetal membranes of preterm delivery with HCA group,preterm delivery without HCA group and normal group were 92%(24/26),65%(24/37),34%(11/32).Comparison of the three groups,preterm delivery with HCA group and preterm delivery without HCA group were higher than normal group,respectively,the difference were statistically significant(P<0.01).In addition,preterm delivery with HCA group was higher than preterm delivery without HCA group,the difference was statistically significant(P<0.01).3.The expression of HSP70 mRNA in fetal membraneThe relative expression of HSP70 mRNA in fetal membranes of preterm delivery with HCA group,preterm delivery without HCA group and normal group were(1.203±0.350),(0.947±0.140),(0.657±0.175).Comparison of the three groups,preterm delivery with HCA group and preterm delivery without HCA group were higher than normal group,respectively,the difference were statistically significant(P<0.01).In addition,preterm delivery with HCA group was higher than preterm delivery without HCA group,the difference was statistically significant(P<0.01).4.The expression of HSP70 protein in fetal membraneThe relative expression of HSP70 protein in fetal membranes of preterm delivery with HCA group,preterm delivery without HCA group and normal group were(1.001±0.055),(0.879±0.041),(0.521±0.032).Comparison of the three groups,preterm delivery with HCA group and preterm delivery without HCA group were higher than normal group,respectively,the difference were statistically significant(P<0.01).In addition,preterm delivery with HCA group was higher than preterm delivery without HCA group,the difference was statistically significant(P<0.01).5.The levels of HSP70 in maternal peripheral blood and umbilical cord bloodThe levels of HSP70 in maternal peripheral blood of preterm delivery with HCA group,preterm delivery without HCA group and normal group were(1.601±0.168)ng/mL,(1.245±0.092)ng/mL,(0.786±0.093)ng/mL;Neonatal umbilical cord blood were(0.935±0.082)ng/mL,(0.756±0.056)ng/mL,(0.577±0.075)ng/mL.Comparison of the three groups,preterm delivery with HCA group and preterm delivery without HCA group were higher than normal group,respectively,the difference were statistically significant(P<0.01).In addition,preterm delivery with HCA group was higher than preterm delivery without HCA group,the difference was statistically significant(P<0.01).6.Correlation analysis of HSP70 in blood and fetal membrane in preterm with HCA groupIn preterm delivery with HCA group,the levels of HSP70 in maternal peripheral blood was positively correlated with umbilical blood(r=0.782,P<0.05).In preterm delivery with HCA group,the levels of HSP70 in maternal peripheral blood was positively correlated with the relative expression of HSP70 protein in fetal membrane(r=0.819,P<0.05).7.Comparison of maternal and neonatal outcomesThree groups of pregnant women were no postpartum hemorrhage and puerperal infection complications.There were 5 cases(19%)of neonatal sepsis in the preterm with HCA group,and there was no neonatal sepsis in others group(F=14.006,P<0.05).ConclusionsHSP70 plays a role in preterm delivery with HCA by activating the innate arm of the immune response;HSP70 may be involved in preterm birth through a variety of mechanisms. |
PDF Full Text Request