Linking the old and new — do angiotensin II type 1 receptor antibodies provide the missing link in the pathophysiology of preeclampsia?

Preeclampsia remains a leading cause of maternal and neonatal morbidity and mortality. The pathophysiology of preeclampsia remains poorly understood with various pathological mechanisms being implicated including the renin angiotensin system (RAAS), angiogenic pathways and various components of the immune system. Recently a pathogenic autoimmune factor has been identified in the form of auto-agonistic angiotensin II type 1 receptor antibodies (AT1-AA). AT1-AA have been studied in vitro and in vivo in various human and animal models and these data have provided compelling evidence for their role in preeclampsia. This review summarises the current literature surrounding the role of AT1-AA in preeclampsia and draws links between this relatively novel antibody to well-established pathological mechanisms including the immune system, the RAAS, angiogenic pathways and placental ischaemia.     

Trophoblast debris modulates the expression of immune proteins in macrophages: a key to maternal tolerance of the fetal allograft?

Interactions between maternal immune cells and the placenta are of substantial interest since diseases of pregnancy, such as recurrent miscarriage, villitis of unknown etiology and preeclampsia may arise due to inadequate adaptation of the maternal immune system. During normal pregnancy trophoblast debris is shed from the placenta into the maternal blood in large quantities. This trophoblast debris is then rapidly cleared from the maternal circulation. In this study, we exposed trophoblast debris generated from an in vitro placental explant model to peripheral blood-derived macrophages and quantified a variety of molecules that are important in immune responses by ELISA or flow cytometry. Phagocytosis of trophoblast debris resulted in reduced cell-surface expression of MHC-II molecules, the costimulatory molecules (CD80, CD86, CD40 and B7H3), monocyte chemoattractant protein-1 (MCP-1), inter-cellular adhesion molecule 1 (ICAM-1) and IL-8 receptors in macrophages while the expression of programmed death-1 ligand 1 (PD-L1) was upregulated. In addition, phagocytosis of trophoblast debris induced the secretion of the anti-inflammatory cytokines IL-10, IL6 and IL1Ra and decreased the secretion of pro-inflammatory cytokines IL-1β, IL12p70 and IL-8 by macrophages. Phagocytosis of trophoblast debris also increased macrophage expression of the immunosuppressive enzyme indoleamine 2,3-dioxygenase (IDO). We have shown that phagocytosis of trophoblast debris from normal placentae alters the phenotype of macrophages such that they are likely to deviate maternal immune responses towards tolerance and away from inflammation. This may be one of the mechanisms that allow the human fetal allograft to survive in direct contact with the maternal immune system.     

Potentiating maternal immune tolerance in pregnancy: A new challenging role for regulatory T cells

The maternal immune system needs to adapt to tolerate the semi-allogeneic conceptus. Since maternal allo-reactive lymphocytes are not fully depleted, other local/systemic mechanisms play a key role in altering the immune response. The Th1/Th2 cytokine balance is not essential for a pregnancy to be normal. The immune cells, CD4+CD25+Foxp3+, also known as regulatory T cells (Tregs), step in to regulate the allo-reactive Th1 cells. In this review we discuss the role of Tregs in foeto-maternal immune tolerance and in recurrent miscarriage as well as their potential use as a new target for infertility treatment. Animal and human experiments showed Treg cell number and/or function to be diminished in miscarriages. Murine miscarriage can be prevented by transferring Tregs from normal pregnant mice. Tregs at the maternal–fetal interface prevented fetal allo-rejection by creating a “tolerant” microenvironment characterised by the expression of IL-10, TGF-β and haem oxygenase isoform 1 (HO-1) rather than by lowering Th1 cytokines. Tregs increase placental HO-1. In turn, HO-1 may lead to up-regulation of TGF-β, IL-10 and CTLA-4. In vivo experiments showed Tregs sensitisation from paternal antigens to be essential for maternal–fetal tolerance. Tregs increase throughout pregnancy and diminish in late puerperium. Recent data also support the capacity of Tregs to block maternal effector T cells, thereby reducing the maternal–fetal pathological responses to paternal antigens. These findings also permit us to consider new strategies for improving pregnancy outcomes, i.e., anti-TNF blockers and granulocyte-colony stimulating factors as well as novel approaches to therapeutically exploiting Treg + cell memory.     

Maternal circulating interferon-gamma and interleukin-6 as biomarkers of Th1/Th2 immune status throughout pregnancy.

AIM: T cells may be classified as T helper type 1 (Th1) cells, which synthesize cytokines inducing cellular immunity, or T helper type 2 (Th2), which synthesize cytokines inducing humoral immunity. According to the Th1/Th2 paradigm, it has been postulated that successful pregnancy induces an immune Th2 bias, but it is not yet clear how Th1 and Th2 systems vary simultaneously throughout the pregnancy. METHODS: Using maternal circulating interferon-gamma (IFN-gamma) and interleukin-6 (IL-6) as biomarkers of Th1 and Th2 cytokines, respectively, we examined the variation of circulating Th1/Th2 ratio in 35 healthy pregnant women from 10 to 40 weeks of pregnancy. RESULTS: With increasing gestational age, maternal circulating levels of IFN-gamma decrease, whereas those of IL-6 increase. The IFN-gamma/IL-6 ratio switches around the 19th week of pregnancy. CONCLUSIONS: Our results suggest that maternal systemic IFN-gamma and IL-6 concentrations may be biomarkers of Th1/Th2 immune status during pregnancy. Moreover, our findings showed that contrary to the Th1/Th2 paradigm, the Th1 bias may be prevailing at the beginning of pregnancy, balanced in the middle of pregnancy and supplanted by the Th2 bias at the end of pregnancy.     

Maternal serum soluble CD30 is increased in normal pregnancy, but decreased in preeclampsia and small for gestational age pregnancies.

OBJECTIVE: Women with preeclampsia and those who deliver small for gestational age (SGA) neonates are characterized by intravascular inflammation (T helper 1 (Th1)-biased immune response). There is controversy about the T helper 2 (Th2) response in preeclampsia and SGA. CD30, a member of the tumor necrosis factor receptor superfamily, is preferentially expressed in vitro and in vivo by activated T cells producing Th2-type cytokines. Its soluble form (sCD30) has been proposed to be an index of Th2 immune response. The objective of this study was to determine whether the maternal serum concentration of sCD30 changes with normal pregnancy, as well as in mothers with preeclampsia and those who deliver SGA neonates. METHODS: This cross-sectional study included patients in the following groups: (1) non-pregnant women (N = 49); (2) patients with a normal pregnancy (N = 89); (3) patients with preeclampsia (N = 100); and (4) patients who delivered an SGA neonate (N = 78). Maternal serum concentration of sCD30 was measured by a specific and sensitive enzyme-linked immunoassay. Non-parametric tests with post-hoc analysis were used for comparisons. A p value <0.05 was considered statistically significant. RESULTS: (1) The median sCD30 serum concentration of pregnant women was significantly higher than that of non-pregnant women (median 29.7 U/mL, range 12.2-313.2 vs. median 23.2 U/mL, range 14.6-195.1, respectively; p = 0.01). (2) Patients with preeclampsia had a significantly lower median serum concentration of sCD30 than normal pregnant women (median 24.7 U/mL, range 7.6-71.2 vs. median 29.7 U/mL, range 12.2-313.2, respectively; p < 0.05). (3) Mothers with SGA neonates had a lower median concentration of sCD30 than normal pregnant women (median 23.4 U/mL, range 7.1-105.3 vs. median 29.7 U/mL, range 12.2-313.2, respectively; p < 0.05). (4) There was no significant correlation (r = -0.059, p = 0.5) between maternal serum sCD30 concentration and gestational age (19-38 weeks) in normal pregnant women. Conclusions: (1) Patients with preeclampsia and those who deliver an SGA neonate had a significantly lower serum concentration of sCD30 than normal pregnant women. (2) This finding is consistent with the view that preeclampsia and SGA are associated with a polarized Th1 immune response and, perhaps, a reduced Th2 response.     

Impaired fetal thymic growth precedes clinical preeclampsia: a case-control study

In preeclampsia the maternal adaptive immune system undergoes specific changes, which are different from the physiological processes associated with healthy pregnancy. Whether preeclampsia also affects the fetal immune system is difficult to investigate, due to limited access to the fetus. We hypothesized that if preeclampsia affects the fetal adaptive immune system this might be associated with early changes in thymic growth. In this case-control study, 53 preeclamptic and 120 healthy control pregnancies were matched for maternal age, gestational age and smoking. Fetal thymus diameter was measured as the greatest width perpendicular to a line connecting sternum and spine based on ultrasound images taken at 17-21 weeks gestation. Independent of fetal and maternal anthropometric measures, thymuses were found to be smaller in preeclamptic pregnancies than healthy controls (16.2 mm versus 18.3 mm, respectively, mean difference=2.1 mm, 95% CI: 0.8-3.3, p<0.001), and the odds of developing preeclampsia was estimated to be 0.72 (95% CI: 0.60-0.86, p<0.001) lower for each 1 mm increase in thymus diameter. There was no correlation between the onset of preeclampsia and fetal thymus size. This is the first study to suggest that fetal thymus growth is reduced before the clinical onset of preeclampsia and precedes any described fetal anomalies or maternal immunological changes associated with preeclampsia. We propose that the fetal adaptive immune system is either passively affected by maternal processes preceding clinical preeclampsia or is actively involved in initiating preeclampsia in later pregnancy.     

Exogenous Soluble VEGF Receptor-1 (sFlt-1) Regulates Th1/Th2 Cytokine Production from Normal Placental Explants via Intracellular Calcium

Objective: The increase of soluble VEGF-Receptor 1 (sFlt-1) is thought to contribute to the pathogenesis of preeclampsia. Soluble VEGF-Receptor 1 binds to circulating free VEGF and PLGF and this cascade is associated with endothelial dysfunction, a prominent feature of preeclampsia. Preeclampsia is also associated with excessive maternal response to pro-inflammatory stimuli manifesting as an imbalance of Th1/Th2 cytokine production at the maternal-fetal interface. Whether increased sFlt-1 expression has any effect on placental production of Th1/Th2 cytokines IL-10 and TNF-α is yet to be investigated. The aim of this study is to examine if exogenous sFlt-1 can regulate Th1/Th2 cytokines IL-10 and TNF-α production from normal placental explants via intracellular calcium release.?Methods: Placental explants were taken from the decidual surface of normal non-laboured term placentas (n = 11).Villous explants were cultured with increasing concentrations of sFlt-1. The dose effect of sFlt-1 on placental Th1 and Th2 cytokine production (TNF-α and IL-10) were examined. Free PLGF, VEGF and sFlt-1 concentrations in the conditioned medium were also measured. Intracellular calcium blocker, 1,2-bis-(o-aminophenoxy)-ethane-N,N,N′,N′-tetraacetic acid, tetra(acetoxymethyl)-ester (BAPTA/AM) was applied to investigate whether the changes in cytokine concentration were mediated by intracellular free calcium.?Results: Placental IL-10 and TNF-α production were significantly increased after sFlt-1 incubation. The increase in IL-10 can be inhibited by BAPTA/AM. Soluble Flt-1 and free PLGF concentration in the conditioned medium was not changed. Free VEGF concentration in the conditioned medium was not detectable.?Conclusion: Exogenous sFlt-1 can increase TNF-α and IL-10 production from normal placental explants. The change in Th1/Th2 cytokine level may be mediated by intracellular free calcium.     

Immunoactivation in preeclampsia: Vδ2+ and regulatory T cells during the inflammatory stage of disease

Recent data suggest a dominant role of the innate, rather than the adaptive immune system in pregnancy-related immunoregulation. γ/δ T cells, that comprise a minor subpopulation of human peripheral blood lymphocytes, represent a link between the innate and the acquired immune systems. However little is known about how they function in preeclampsia, which is suggested to be associated with a Th1 predominant immune response. The aim of our study was to investigate the presence and phenotype of Vδ2+ cells and of regulatory T cells in the pathogenesis of preeclampsia. Since Vδ2+ T cell function has been shown to be altered in patients with preeclampsia we investigated the expression of perforin, Fas and TIM-3 by Vδ2+ T cells and the possible role of activating and inhibitory NK cell receptors as well as of regulatory T cells. Vδ2+ T cells of preeclamptic patients demonstrated an increased perforin and IFNγ production, which could be explained by dysregulation of NK cell receptor expression. These Th1 polarized cells were less susceptible to apoptosis than Vδ2+ T cells from healthy pregnant women. Our data suggest that activated Vδ2+ T cells of preeclamptic women have an increased cytotoxic potential, which may be due to altered expression of NK cell inhibitory and activating receptors. In this study we report a series of observations, which taken together suggest the role of multiple pathways in generating an exaggerated systemic inflammatory response observed in the clinical stage of preeclampsia.     

阿奇霉素治疗沙眼衣原体感染孕鼠对其妊娠结局及免疫状态的影响

目的:了解沙眼衣原体感染孕鼠的妊娠结局与体内Th1型、Th2型细胞因子水平的关系,以及阿奇霉素干预治疗对其免疫状态及妊娠结局的影响,探讨沙眼衣原体致不良妊娠结局的免疫机理。方法:随机将孕鼠分成3组,于孕2、3、4天,对照组阴道内接种无感染衣原体由McCoy细胞制备的SPG悬液30μl,模型组阴道内接种1.0×106IFU/ml沙眼衣原体F型株的SPG悬液30μl,给药组阴道接种衣原体后于妊娠第8天腹腔注射阿齐霉素10mg/kg(单次给药)。孕12天用酶联免疫法检测各组小鼠血清中Th1型(IFN-γ、TNF-α)/Th2型(IL-4、IL-10)细胞因子表达水平,计算IL-4/TNF-α,IL-10/TNF-α比率。用方差分析和χ2检验比较3组的妊娠失败率、胚胎吸收率、胎重、孕期体重增加量等,以及3组之间细胞因子水平及Th1/Th2型免疫调节平衡的比率等。结果:模型组与对照组比较体内Th2型细胞因子下降(IL-10),而Th1型细胞因子上升(TNF-α),且代表Th1/Th2型免疫调节平衡的细胞因子比值:IL-4/TNF-α,IL-10/TNF-α模型组显著低于对照组,形成Th1型免疫偏倚。给药组降低了妊娠失败率并降低了Th1型免疫偏倚程度。模型组小鼠妊娠失败率及反复妊娠失败率显著高于对照组;给药组小鼠妊娠失败率较模型组低而较对照组高,反复妊娠失败率较模型组下降明显(P0.05);3组的胚胎吸收率,胚重,孕期体重增加量无显著差异。结论:阴道接种沙眼衣原体使体内细胞因子向Th1型漂移,增加了小鼠的妊娠失败率;阿奇霉素干预可降低Th1型漂移程度,降低小鼠妊娠失败率。     

Glucocorticoids inhibit placental cytokines from cultured normal and preeclamptic placental explants

Glucocorticoids are used in pregnancy to enhance fetal lung maturity as well as to ameliorate antepartum and postpartum HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome, but it is not clear if glucocorticoids can modulate placental cytokine production. The aim of this study is to examine the effect of glucocorticoids at equivalent doses used for fetal lung maturity on placental tissue production of cytokines (IL-10, IL-6 and TNF-alpha). Placental biopsies were taken from the decidual surface of term placentas of normal pregnancy (n = 5) and preeclampsia (n = 5). Villous explants were cultured with increasing concentrations of glucocorticoids (betamethasone and methyl-prednisolone, 0.0025 microM, 0.25 microM and 25 microM). The dose effect of glucocorticoids on cytokines (TNF-alpha, IL-6 and IL-10) production was examined using ELISA. There was a stepwise reduction of TNF-alpha (23.6-97.5% reduction) and IL-6 (13.7-71% reduction) with increasing doses of betamethasone and methyl-prednisolone from placentas of women with preeclampsia and normal pregnancy. However, IL-10 was not altered in conditioned medium by increasing doses of glucocorticoids. Our data suggest that the ratio of pro-inflammatory to anti-inflammatory cytokine (Th1/Th2) is potentially altered by exogenous glucocorticoids. These changes have a favourable effect on the ratio in preeclampsia with a reduction in the potentially vascular active pro-inflammatory cytokines but without altering or decreasing the necessary anti-inflammatory cytokine IL-10 production in placental tissue.     

Th1/Th2 balance in preeclampsia

The syndrome of preeclampsia has previously been ascribed to generalized maternal endothelial dysfunction, poor placentation and excessive maternal inflammatory response. Recent reports suggest that preeclampsia is associated with a Th1 predominant profile and may be considered as a failure of the tolerance system allowing the second physiological trophoblastic invasion. In this review, we discuss that Th1 predominant immunity is closely related to inflammation, endothelial dysfunction and poor placentation.     

Dendritic cells in the circulation of women with preeclampsia demonstrate a pro-inflammatory bias secondary to dysregulation of TLR receptors

Toll-like receptors (TLRs) are central components of the innate immune system that recognize both microbial ligands and host products released during tissue damage. Data from epidemiologic studies and animal models suggest that inappropriate activation of the immune system plays a critical role in the development of preeclampsia. This study evaluates in a systematic fashion the expression and function of TLRs in the circulation of patients with preeclampsia compared to healthy pregnant controls. We evaluated TLR expression and function in primary dendritic cells (DCs) of 30 patients with preeclampsia and 30 gestational age-matched healthy pregnant controls. DCs were stimulated with the different TLR ligands engaging TLR1/2, TLR2/6, TLR3, TLR4, TLR5, TLR7, TLR8 and TLR9. The expression of TLR-induced production of TNF-α, IFN-α, IL-6, and IL-12 were measured by multicolor flow cytometry. Basal expression of TLR3, TLR4 and TLR9 was significantly increased in DCs isolated from women with preeclampsia. Preeclamptic DCs also expressed significantly higher basal levels of cytokines. In contrast, preeclamptic DCs demonstrated a less robust response to stimulation with various TLR ligands as compared with healthy pregnant controls. Under basal conditions, DCs from preeclamptic individuals express higher levels of select TLRs and produce more pro-inflammatory cytokines as compared with healthy controls. As such, the ability of these cells to mount an inflammatory reaction in response to a TLR ligand is limited. These data demonstrate a dysregulated pattern of TLR expression and cytokine production in DCs from PE patients that may limit further activation by TLR engagement.     

The role of cytokines at the fetomaternal interface]

Various mechanisms are necessary for regulating the survival of the semiallogenic embryo in the maternal organism. In addition to the lack of classical MHC class I and II antigens at the trophoblast the cytokines play an important role at the fetomaternal interface. Different cytokines regulate the immunological processes with an emphasis on the Th1/Th2 balance. In contrast to the peripheral blood there is a certain composition of immune competent cells at the fetomaternal interface. There are many different interactions between the endocrine and immunological system. Hormones modulate the secretion of certain cytokines and vice versa. In reproductive medicine it is of specific interest to evaluate these functions for treating problems during the early pregnancy.     

Cellular inhibitors of apoptosis (cIAP) 1 and 2 are increased in placenta from obese pregnant women

Introduction

Independent of their role in apoptosis, cellular inhibitors of apoptosis (cIAP) 1 and 2, have emerged as regulators of inflammation. Obesity in pregnancy is characterised by maternal and placental inflammation. Thus, the aim of this study was to determine the effect of maternal obesity and pro-inflammatory mediators on cIAP expression in human placenta.

Methods

The expression of cIAP was assessed in human placenta from lean (n = 15) and obese (n = 14) patients by qRT-PCR and Western blotting. Primary trophoblast cells were used to determine the effect of pro-inflammatory cytokines on cIAP expression, and the effect of cIAP siRNA on pro-inflammatory cytokines.

Results

cIAP1 and cIAP2, gene and protein expression were significantly higher in placenta from women with pre-existing maternal obesity compared to placenta form lean women. Additionally, bacterial endotoxin LPS and the pro-inflammatory cytokines tumour necrosis factor (TNF)-α and interleukin (IL)-1β significantly increased the expression of both cIAP1 and cIAP2 in primary trophoblast cells isolated from human term placenta. Knockdown of cIAP1 or cIAP2 in human primary trophoblast cells significantly decreased TNF-α induced expression and secretion of pro-inflammatory cytokines IL-6 and IL-8 and of matrix metalloproteinase (MMP)-9.

Discussion

cIAP1 and cIAP2 expression is increased in placenta from women with pre-existing maternal obesity and in response to treatment with pro-inflammatory cytokines. Functional studies in placental trophoblast cells revealed that cIAPs are involved in TNF-α induced-expression of pro-inflammatory cytokines. Given the central role of pro-inflammatory cytokines in placental nutrient transport, this data suggest that cIAP1 and cIAP2 may play a role in fetal growth and development.     

Gene expression of the constant region of the heavy chain of immunoglobulin G (IgG CRHC) is down-regulated in human decidua in association with preeclampsia

An aberrant interaction at the maternal/fetal interface between the genetically distinct fetal trophoblast cells and cells of the maternal decidua has been proposed as an initiating factor in one of the major complications of human pregnancy, preeclampsia. Biochemical and epidemiological studies suggest that the immune system plays an important role in preeclampsia. Thus, the aim of this study was to determine the decidual gene expression status in preeclampsia of one of the key components of the adaptive immune system. Total RNA was extracted from decidua collected from women with normal pregnancies and those complicated by preeclampsia. Reverse Northern analysis was performed on 72 cDNAs from human decidua and differentially expressed genes identified were analysed further using semi-quantitative RT-PCR and Northern blot analysis. Expression of the gene encoding the constant region of the heavy chain of immunoglobulin G (IgG CRHC) was shown to be down-regulated in association with preeclampsia. These data support the hypothesis that immune maladaptation may play an important role in the pathogenesis of preeclampsia.     

The predominance of Th17 lymphocytes and decreased number and function of Treg cells in preeclampsia

The aim of this study was to estimate the prevalence of CD3(+)CD4(+) T lymphocytes producing IL-17, IL-2, IFN-γ, and IL-4, plus CD4(+)CD25(+)FoxP3(+) T regulatory (Treg) cells, in peripheral blood of patients with preeclampsia and healthy women in the third trimester of normal pregnancy. Another purpose was to assess the immunosuppressive activity of Treg cells from patients with preeclampsia compared with controls. Thirty-four preeclampsia patients and 27 healthy pregnant women were included. The percentages of CD4(+)CD25(+)FoxP3(+) Treg cells and CD3(+)CD4(+) T lymphocytes with intracellular expressions of cytokines were estimated using monoclonal antibodies and flow cytometry. In vitro functional assays were performed using a Treg Cell Isolation Kit and (3)H-thymidine incorporation assays. The percentage of CD3(+)CD4(+) T lymphocytes producing IL-17A was significantly higher in preeclampsia than in healthy, normotensive pregnant women in the third trimester (p<0.001). The population of CD4(+)CD25(+)FoxP3(+) Treg cells was significantly lower in the study group compared with controls (p<0.05). There was no change in the stimulation index of CD3(+)CD4(+)CD25(-) T lymphocytes from preeclampsia patients without Treg cells and after addition of autologous Treg cells. In normal pregnancy, the stimulation index of CD3(+)CD4(+)CD25(-) T lymphocytes was significantly higher without Treg cells compared with the response after addition of autologous Treg cells (p<0.05). The results suggest up-regulation of the Th17 immune response in preeclampsia. The decreased number and function of Treg cells may be responsible for activating the inflammatory response characteristic of this disorder. In preeclampsia, the predominance of Th17 immunity could act through modulating the Th1/Th2 immune balance.     

Plasma IL-4, IL-8, IL-12, interferon-γ and CRP levels in pregnant women with preeclampsia,and their relation with severity of disease and fetal birth weight

Objective: The aim of the present study was to evaluate the hypothesis that preeclampsia is associated with increased systemic inflammatory responses of Th1-type as well as decreased Th2-type responses compared with normal pregnancy. We also sought to determine whether there was a correlation between these markers with severity of preeclampsia and fetal birth weight. Methods: The study population consisted of maternal age, gestational age, and body mass index matched 138 pregnant women; 56 normotensive healthy pregnant women (group 1), 42 women with mild preeclampsia (group 2), 40 women with severe preeclampsia (group 3). Results: Plasma interleukin (IL)-8 and C-reactive protein (CRP) levels were significantly higher in group 3 than group 1 (p?<?0.05). Plasma IL-4, IL-12, and interferon (IFN)-γ levels were similar in all groups. Although plasma IL-8 and CRP levels of mild preeclamptic group were higher than control group and lower than severe preeclamptic group, the differences were not statistically significant. There was a positive correlation between IL-12 and fetal birth weight in severe preeclamptic group (p?<?0.05). Conclusions: Elevated maternal serum pro-inflammatory cytokine IL-8 and CRP in severe preeclamptic women compared with normal pregnant women supports the hypothesis that preeclampsia is associated with increased inflammatory responses.     

Th1/Th2细胞因子在妊高征患者胎盘组织中的表达

目的 :探讨T辅助细胞 (Th) 1/Th2细胞因子在妊娠高血压综合征 (PIH)孕妇和血压正常的晚期妊娠妇女 (NLP)胎盘中的表达规律 ,从免疫学角度研究妊高征的发病原因及机制。方法 :选取PIH和NLP孕妇作为研究组和对照组 ,应用原位杂交法对两组胎盘的Th1型细胞因子 [肿瘤坏死因子 (TNF)α、白细胞介素 (IL) 2 ]和Th2型细胞因子 (IL 10 )进行标记并通过彩色病理图像分析系统对染色结果进行定量检测并作比较。结果 :(1)TNFαmRNA、IL 2mRNA在PIH及NLP组胎盘合体滋养细胞表达的平均光密度分别为0 .1978± 0 .0 32 1、0 .2 0 39± 0 .0 4 11及 0 .16 79± 0 .0 30 9、0 .16 0 0± 0 .0 4 46 (P <0 .0 0 1) ,随着PIH病情加重 ,表达逐渐增强 (P <0 .0 5 ) ;(2 )IL 10mRNA在PIH及NLP组胎盘合体滋养细胞表达的平均光密度分别为 0 .15 6 4± 0 .0 4 36及 0 .2 0 17± 0 .0 32 1(P <0 .0 0 1) ,随着PIH病情加重 ,表达逐渐减弱 (P <0 .0 5 )。结论 :在妊高征孕妇胎盘中表现为免疫杀伤的Th1型细胞因子表达增强 ,与病情呈正相关。表现为免疫保护或免疫营养的Th2型细胞因子则表达减弱 ,与病情呈负相关。提示母胎界面的Th1/Th2细胞因子平衡偏离可能是导致PIH发病的病因之一。     

Th1/Th2平衡调控对妇产科疾病影响的研究进展

近年来研究发现辅助性T细胞1型（Th1）/Th2的平衡调控与妇产科疾病的发生、发展、治疗和转归有密切的关系。Th1细胞调节细胞免疫,主要促进炎症反应和细胞毒性活动;Th2细胞调节体液免疫,主要刺激细胞的分化与增殖。Th1细胞通过合成γ干扰素（IFN-γ）抑制Th2细胞功能,Th2细胞通过合成白细胞介素4（IL-4）抑制Th1细胞的功能,二者相互作用、相互调节。正常妊娠情况下Th1/Th2细胞应答存在生理性失衡,母体Th2型细胞因子抑制Th1型细胞因子的产生,这种生理性失衡被破坏可导致复发性流产、早产、子痫前期及不孕症等妊娠相关疾病。而宫颈癌、卵巢癌、子宫内膜异位症等妇科疾病与Th1/Th2平衡调控有关,但其确切免疫学机制尚不明确,尚需进一步深入研究,以期为多种妇产科疾病的免疫学治疗开辟新的前景。     

Maternal serum soluble CD30 is increased in normal pregnancy,but decreased in preeclampsia and small for gestational age pregnancies

Objective. Women with preeclampsia and those who deliver small for gestational age (SGA) neonates are characterized by intravascular inflammation (T helper 1 (Th1)-biased immune response). There is controversy about the T helper 2 (Th2) response in preeclampsia and SGA. CD30, a member of the tumor necrosis factor receptor superfamily, is preferentially expressed in vitro and in vivo by activated T cells producing Th2-type cytokines. Its soluble form (sCD30) has been proposed to be an index of Th2 immune response. The objective of this study was to determine whether the maternal serum concentration of sCD30 changes with normal pregnancy, as well as in mothers with preeclampsia and those who deliver SGA neonates.

Methods. This cross-sectional study included patients in the following groups: (1) non-pregnant women (N = 49); (2) patients with a normal pregnancy (N = 89); (3) patients with preeclampsia (N = 100); and (4) patients who delivered an SGA neonate (N = 78). Maternal serum concentration of sCD30 was measured by a specific and sensitive enzyme-linked immunoassay. Non-parametric tests with post-hoc analysis were used for comparisons. A p value <0.05 was considered statistically significant.

Results. (1) The median sCD30 serum concentration of pregnant women was significantly higher than that of non-pregnant women (median 29.7 U/mL, range 12.2–313.2 vs. median 23.2 U/mL, range 14.6–195.1, respectively; p = 0.01). (2) Patients with preeclampsia had a significantly lower median serum concentration of sCD30 than normal pregnant women (median 24.7 U/mL, range 7.6–71.2 vs. median 29.7 U/mL, range 12.2–313.2, respectively; p < 0.05). (3) Mothers with SGA neonates had a lower median concentration of sCD30 than normal pregnant women (median 23.4 U/mL, range 7.1–105.3 vs. median 29.7 U/mL, range 12.2–313.2, respectively; p < 0.05). (4) There was no significant correlation (r = ?0.059, p = 0.5) between maternal serum sCD30 concentration and gestational age (19–38 weeks) in normal pregnant women.

Conclusions. (1) Patients with preeclampsia and those who deliver an SGA neonate had a significantly lower serum concentration of sCD30 than normal pregnant women. (2) This finding is consistent with the view that preeclampsia and SGA are associated with a polarized Th1 immune response and, perhaps, a reduced Th2 response.