Serum- and cell-mediated immune protection of mouse placenta and fetus against a Brucella abortus challenge: expression of barrier effect of placenta

When mice are intravenously inoculated with a virulent Brucella abortus strain at day 12 to 14 of pregnancy and killed three to five days later, colonization of placentae, fetuses and spleens can be estimated by the frequency and level (bacterial count) of infection and by linkage between individual placental and paired fetal infections. This linkage indicates the placental barrier effect, defined as the number of non-infected fetuses linked to 100 colonized placentae. Immune mice serum raised against two Brucella fractions injected one day before challenge (1) restricted the placental colonization (the dose required to infect 50 per cent placentae was increased by 50 to 70 times compared to controls), (2) decreased the level of splenic and placental infection, and (3) increased the barrier effect so that most fetuses were protected even when linked to a heavily infected placenta. Immune (B + T) spleen cells from mice vaccinated with a Brucella cell-wall fraction transferred to recipients seven to eight days before mating, that is, 22 days before challenge (1) restricted the frequency of placental and fetal colonization, (2) decreased the level of splenic, placental and fetal infections, and (3) increased the barrier effect. However, separated B- and T-cells were less active, in particular on the level of fetal infection. In contrast with serum, the cells did not decrease infection of the fetuses linked to heavily infected placentae.     

Placental-ovarian relationship in the control of testosterone secretion in the rat

Both ovaries and placentae of rats produce androgen in the second half of pregnancy. The objectives of this investigation were to determine whether the pituitary controls both ovarian and placental secretion of testosterone, to find out whether ovarian secretion of testosterone is maintained by the placenta, and to examine whether levels of testosterone produced by the ovaries and placentae depend upon the number of placentae present. Pregnant rats were hypophysectomized with or without hysterectomy in one experiment, and hypophysectomized with or without partial hysterectomy leaving one placenta in situ in another experiment. Testosterone output by the placenta(e) or the ovary was quantified. The results suggest that placental secretion of testosterone is independent of the pituitary between days 12 and 18 of pregnancy, reduction in placental number causes the remaining placenta to compensate by increasing its testosterone output, and ovarian secretion of testosterone may be under placental control between days 12 and 18 of pregnancy.     

Immunohistochemical localization of pregnancy-associated plasma protein A (PAPP-A) in placentae from normal and pre-eclamptic pregnancies

An immunohistochemical method was used to locate pregnancy-associated plasma protein A (PAPP-A) in the placenta and uterus. In addition to 10 placentae and basal plates from normal pregnancies, ranging in gestational age from 37 to 40 weeks, the following specimens were studied: three uteri obtained by hysterectomy during early pregnancy; and three placentae from patients with severe hypertensive pre-eclampsia. In early gestation, PAPP-A was localized in the villous cytotrophoblastic cell layer and the endometrial glands but was not found in the villous syncytiotrophoblast, the cytotrophoblastic cell columns or the decidual cells. On histochemical examination of placentae from cases of pre-eclampsia with hypertension, an increased number of villous cytotrophoblastic cells and so-called X-cells was observed. The monospecific antiserum to PAPP-A reacted strongly and evenly with the cytoplasm of these cells. The present study strongly suggests that the active production sites of PAPP-A are the villous cytotrophoblastic cells and the X-cells.     

Localization of ubiquitin carboxyl-terminal hydrolase-L1 in cynomolgus monkey placentas

Ubiquitin carboxyl-terminal hydrolase-L1 (UCH-L1) is a restrictedly expressed enzyme in neural and reproductive tissues, and it is considered to have a significant role in reproduction. In the present study, we investigated the localization of UCH-L1 in placenta of cynomolgus monkeys (Macaca fascicularis). UCH-L1 protein was detected in cytotrophoblasts of chorionic plate and villi, and decidual cells of decidua basalis in cynomolgus monkey placenta, and the amount of UCH-L1 protein in whole placenta increased as pregnancy progressed. These results supported that UCH-L1 is necessary for placental and fetal development in primate placenta. This is the first report to demonstrate the presence of UCH-L1 in primate placenta, and the cynomolgus monkey may be a useful model for the study of the functions of the ubiquitin-proteasome system in human pregnancy.     

Studies on the localization of 5-hydroxytryptamine and its receptors in human placenta

The localization of 5-hydroxytryptamine (5-HT) and its receptors in human placenta was studied under light and electron microscopy using immunohistochemistry and in situ hybridization. The syncytiotrophoblast, cytotrophoblast, stromal cells and decidual cells in human placentae all appeared to be 5-HT immunoreactive. The 5-HT immunoreactive material was distributed in cytoplasm with negative nuclei. The 5-HT immunoreactive material was also found in capillary endothelium. Trophoblast cells cultured in serum-free medium also showed 5-HT immunoreactivity in the cytoplasm. Fetal white blood cells and both syncytiotrophoblast and cytotrophoblast in human placenta showed 5-HT receptor immunoreactivity and 5-HT₁A receptor mRNA hybridized signal was also detected in cytoplasm. The stromal cells and capillary endothelium in placental villi and maternal decidual cells all showed 5-HT receptor immunoreactivity in cytoplasm. The small flattened vesicles and large dense cored vesicles within trophoblast cells showed electron-dense 5-HT receptor immunoreactivity using immunoelectron microscopy. These results suggest that human placenta may not only produce 5-HT but also be a 5-HT target organ, and that 5-HT may not only play roles in placental development and pregnancy maintenance by paracrine and autocrine interactions but may also take part in regulating fetal development.     

妊娠肝内胆汁淤积症患者胎盘细胞凋亡及调控基因的研究

目的　通过观察妊娠肝内胆汁淤积症 (ICP)患者胎盘细胞凋亡调控基因p5 3、bax和bcl 2在胎盘中的表达 ,探讨细胞凋亡基因在胎盘细胞凋亡中的作用。方法　采用原位末端标记法(TUNEL)和免疫组织化学方法对 3 1例ICP患者 (ICP组 )的胎盘组织中p5 3、bax和bcl 2基因表达及调亡指数进行检测 ,并以 3 1例正常妊娠妇女的胎盘组织作对照 (对照组 )。结果　 (1)ICP组胎盘组织中细胞滋养细胞、合体滋养细胞、蜕膜细胞及间质细胞中细胞凋亡指数分别为 (49 1± 9 1) %、(46 6±9 8) %、(3 5 1± 9 5 ) %、(3 8 7± 9 7) % ,明显高于对照组的 (2 2 5± 6 2 ) %、(2 1 6± 5 2 ) %、(17 9±6 2 ) %、(17 0± 4 7) %。两组比较 ,差异有极显著性 (P <0 0 1)。 (2 )而调控基因p5 3的表达 ,ICP组明显高于对照组 ,两组比较 ,差异有极显著性 (P <0 0 1) ;bax的表达在两组滋养细胞中比较 ,差异无显著性 (P >0 0 5 )。但在合体滋养细胞、蜕膜细胞及间质细胞中 ,ICP组明显高于对照组 ,两组比较 ,差异有极显著性 (P <0 0 1) ;bcl 2的表达在ICP组胎盘组织细胞滋养细胞、合体滋养细胞、蜕膜细胞及间质细胞中 ,均明显低于对照组 (P <0 0 1)。 (3 )p5 3、bax和bcl 2在ICP组合体滋养细胞中的表达分别是 (75 9± 8 2 ) %、(65     

Differential localization of decidual stathmin during pregnancy in rats

The present study was undertaken to determine the precise localization of stathmin, a protein associated with microtubule dynamics, during decidualization in rat uterus and to compare it with that of cyclin D3. Immunohistochemical analysis revealed that stathmin is exclusively localized in decidual cells, especially in the primary decidual zone surrounding the embryo, on days 7 and 9 of pregnancy. The intensity of staining was much higher on day 9 than day 7. On day 14, when the endometrial stromal cells had completely differentiated into decidual cells, the staining of decidual cells was faint. Cyclin D3 was expressed in decidual cells of the secondary but not the primary decidual zone on days 7 and 9. On day 14, cyclin D3 levels were low in decidua. Proliferating cell nuclear antigen (PCNA) was broadly detected in the uterus on days 7 and 9, and in the placenta and fetus on day 14. In an artificial decidualization model, cyclin D3 expression was stimulated as deciduoma was formed after an artificial stimulus. Stathmin mRNA levels also increased within 24 h and peaked at 48 h. The specific spatio-temporal uterine expression of stathmin and cyclin D3 suggest that they have a specific role in decidualization in rats.     

Angiotensin II type 1 receptor has impact on murine placentation

Impaired placentation is a key step in the pathogenesis of important pregnancy disorders such as preeclampsia and fetal growth restriction. A role of angiotensin II in placental development can be assumed from the expression of angiotensin receptors on trophoblast from the earliest stages of pregnancy. To understand the role of angiotensin II type 1 (AT1) receptors in placental development, we investigated placentae of AT1a-deficient mice early in pregnancy (day 13 postconception). The number of alive newborns was significantly reduced in AT1a-deficient mice caused by placental malformations in 30% of all utero-placental units. Importantly, no embryonic structure was observable within the uterine segments harboring the malformed placentae. Immunohistochemistry with an antibody against murine betahCG-equivalent stained homogenously in almost all cells in the altered placentae indicating still an endocrine-active trophoblast. However, the typical structure of the murine wild-type placenta in spongiotrophoblast, giant cells, and labyrinth was abolished in malformed placental tissue deficient in the AT1a receptor. Recent epidemiological studies revealed the detrimental effect of an AT1 blockade for fetal outcome due to renal malformations and a reduced birth weight. For the latter, our findings provide an early mechanistic explanation. The lack in AT1 stimulation causes an impaired trophoblast maturation leading to impaired placental function.     

Increased superoxide generation is associated with decreased superoxide dismutase activity and mRNA expression in placental trophoblast cells in pre-eclampsia

Pre-eclampsia is a multi-system disorder unique to human pregnancy. Although the aetiology of pre-eclampsia is still unknown, increased placental oxidative stress contributes to the pathophysiology of this pregnancy disorder. The goal of this study was to determine if placental trophoblast cells generate superoxide, and if there was a difference in superoxide generation and superoxide dismutase (SOD) activity between trophoblast cells isolated from pre-eclamptic placentae versus normal placentae. Placentae were obtained from nine normal and 10 pre-eclamptic pregnancies immediately after delivery. Trophoblast cells were isolated and purified by Percoll density gradient centrifugation. Superoxide generation and SOD activity were determined by spectrophotometric assays. Localization of CuZn-SOD protein within the placenta was examined by immunohistochemical staining. mRNA expression of CuZn-SOD was determined in trophoblast cells isolated from five normal and five pre-eclamptic pregnancies by Northern blot analysis. 18S ribosomal mRNA expression was used as an internal standard. We found: (1) trophoblast cells from pre-eclamptic placentae generated significantly more superoxide than trophoblast cells from normal placentae: 17.62+/-3.19 versus 4.70+/-0.76 nmol/5x10(6) cells (mean+/-s.e.), P< 0.01; (2) protein and mRNA expression for CuZn-SOD was mainly localized in the trophoblast cells within the placenta; and (3) SOD activity and relative mRNA expression for CuZn-SOD were significantly decreased in trophoblast cells from pre-eclamptic placentae as compared to trophoblast cells from normal placentae, SOD activity: 6.46+/-1.76 versus 13.01+/-1.67 units/mg protein, P< 0.05; relative mRNA expression for CuZn-SOD: 0.25+/-0.09 versus 0.73+/-0.07, P< 0.01. We conclude that increased superoxide generation was associated with decreased SOD activity and mRNA expression for CuZn-SOD in trophoblast cells isolated from pre-eclamptic placentae. These findings support the notion of increased oxidative stress in the pre-eclamptic placenta, which may contribute to the pathophysiology of this pregnancy disorder.     

Picornavirus infection in early murine gestation: significance of maternal illness

To evaluate whether maternal illness following picornavirus infection during pregnancy adversely affects placental and fetal health, mice were inoculated with the GDVII strain of Theiler's murine encephalomyelitis virus or control cell lysate during days 4-7 of gestation. Gross appearance, histopathology and viral culture, and in situ hybridization positivity of placentae and fetuses from ill GDVII-infected, healthy GDVII-infected and control mice were compared. Twenty of 34 (59 per cent) GDVII-infected dams became clinically ill. More placenta-fetus pairs from ill mice were grossly abnormal (68 per cent) than from well GDVII-infected (51 per cent;P< 0.01) or control mice (9 per cent;P< 0.001). Virus was detected by in situ hybridization in 73 per cent of placentae and 29 per cent of fetuses from sick GDVII-infected dams, and in 85 per cent of placentae and 19 per cent of fetuses from healthy GDVII-infected mice (differences not significant). Histological abnormalities consisting of necrosis or an increase in hyaline tissue in the vascular labyrinth layer were similarly frequent in placentae from ill and well GDVII-infected mice (58 per cent versus 67 per cent, P=0.5). Viral RNA, inflammation and necrosis were evident in the heart, great vessels, brain and spinal cord of GDVII-infected fetuses. Infection with GDVII in early pregnancy produces a high rate of gross placental and fetal abnormalities. The rate of gross abnormalities exceeds the incidence of fetal infection and more closely parallels the rates of infection and histopathology in the placenta, suggesting that much of the damage to placenta-fetus pairs is a consequence of placental infection. In addition, the occurrence of viral-induced maternal illness is associated with additive risk to placental and fetal health not explained by an increased rate of placental or fetal infection.     

乙肝病毒母婴垂直传播胎盘超微结构变化

目的　通过对乙肝病毒 (HBV)母婴垂直传播者胎盘超微结构的观察 ,探讨 HBV母婴垂直传播的细胞学机制。　方法　用 EL ISA双抗夹心法对孕妇静脉血及其胎儿脐血、新生儿静脉血进行 HBV检测。对 5例发生 HBV母婴垂直传播者胎盘用 JEM- 12 0 0 EM透射电镜观察超微结构变化。　结果　 HBV双抗原阳性孕妇 6 0 %发生 HBV母婴垂直传播。HBV母婴垂直传播胎盘的超微结构改变有 :胎盘合体细胞内核糖体增多 ,微绒毛增多、变形 ,合体细胞变性坏死 ;胎盘屏障中毛细血管基底膜增厚、纤维蛋白样物沉积 ,合体细胞间隙、胞浆、细胞核内见多种病毒样颗粒。　结论　 HBV可感染胎盘合体细胞并且在其中复制 ,从而使胎儿在宫内被感染。     

HtrA3, a serine protease possessing an IGF-binding domain, is selectively expressed at the maternal-fetal interface during placentation in the mouse

Hemochorial placentation involves highly regulated interactions between fetal- and maternal-derived cells. HtrA3, a novel serine protease containing an insulin-like growth factor (IGF) binding domain, was previously shown to increase during early pregnancy in the mouse uterus, being dramatically upregulated post-implantation. The present study examined the regulation of HtrA3 gene in the mouse uterus from post-implantation to late gestation. Both mRNA and protein of HtrA3 were localized specifically in the maternal decidua. In contrast, HtrA3 expression was below detection in trophoblasts, including the giant cells that are in direct contact with the decidua. This pattern persisted from the early stages of placentation to near term. The level of decidual HtrA3 mRNA and its protein gradually decreased as the placenta matured. In the decidua, only the maternal decidual cells, but not blood vessels or uterine NK cells that are present in large numbers, were positive for HtrA3. The specific localization of a protease possessing an IGF-binding domain at the maternal-fetal interface suggests that HtrA3 plays a critical role in mediating maternal decidual remodelling and maintenance, likely in association with the IGF system, in placental development and function.     

The value of ultrasonic placental grading: no correlation with intrauterine growth retardation or with maternal smoking

In a prospective study the usefulness of placental grading in detecting IUGR has been evaluated. Those who were echoscopically examined within one week before delivery were taken into the study (n = 137). Changes in placental tissue increased clearly as pregnancy progressed and in 42% (57/137) the placentae reached Grade III. Increasing placental grading is associated with normal maturation of the placenta. Post partum examination of the placenta correlated well with the echoscopic picture (accuracy = 80.5%). No relationship was found in an unselected group between Grade III and IUGR at term. When a Grade III placenta was first seen before 36 weeks, in three out of five cases a growth retarded neonate was born. The effects of maternal smoking habits during pregnancy on birth weight and placenta were examined. There were no significant differences in mean placental weight, placental ratio and placental grading as the amount of cigarettes increased. The mean birth weight and birth weight percentile decreased significantly when the mother smoked more than 10 cigarettes per day.     

The effects of unilateral ovariectomy during pregnancy on placental and fetal growth in mice

A comparison between placental weight and number of fetuses in normal mice and those in mice unilaterally ovariectomized on the sixth day of pregnancy, revealed a relative hypertrophy of the placentae of the latter group, with a predominance of the effect in litter sizes of five or less. The weights of the fetuses in the unilaterally ovariectomized group were not significantly different from those of the controls, thus affording no evidence of a causal connection between fetal weight and gross placental weight.     

Effect of placental tissue on inhibition of uterine contraction by nitric oxide donors.

OBJECTIVE: Our purpose was to test the hypothesis that placental tissue modulates the effect of nitric oxide on spontaneous uterine contractility in pregnant rats. STUDY DESIGN: Rings (approximately 4 mm) of uterus taken from rats on day 14 (midpregnancy, n = 6), day 18 (late pregnancy, n = 4), and day 22 (term, n = 4) of gestation were placed in organ chambers filled with Krebs-bicarbonate buffer bubbled with 5% carbon dioxide in air (37 degrees C, pH approximately 7.4) for isometric tension recording. In some rings a piece of placenta was left attached to the uterine wall. In the other rings the fetuses, placentas, and membranes were removed completely. Change of spontaneous contractions of the rings (percentage change of basal integral activity for 10 minutes) in response to cumulative concentrations of the nitric oxide donors diethylamine-nitric oxide and nitroglycerin (10(-6) mol/L to 10(-4) mol/L) were compared between rings with and without placenta. RESULTS: Diethylamine-nitric oxide and nitroglycerin inhibited spontaneous uterine contractions in rings from midpregnancy, in both the absence and the presence of placenta. In rings from midpregnancy, the maximal inhibition of contractions by diethylamine-nitric oxide but not by nitroglycerin was significantly (P <.05) higher in the presence (26.7% +/- 3.5% of basal activity) than in the absence (39. 6% +/- 3.3%) of placenta. Inhibition of contraction by nitric oxide donors in rings from late and term pregnancy was less than in midpregnancy, and the presence of placental tissue did not influence the responses. CONCLUSIONS: The presence of placental tissue enhances inhibition of uterine contractility by agents that spontaneously release nitric oxide, such as diethylamine-nitric oxide, but not by nitroglycerin, which requires metabolic transformation for nitric oxide to be released. Refractoriness to nitric oxide near or at term does not depend on the presence or absence of placental tissue.     

Expression of mitochondrial thioredoxin-dependent antioxidant protein, SP-22, in normal human and inflammatory mouse placentae

The aim of this study was to elucidate whether a novel mitochondrial antioxidant protein, SP-22, is localized in placenta and whether its expression is induced in placenta of lipopolysaccharide (LPS)-exposed mouse. Western blot analysis of normal human placenta indicated that the SP-22 protein was located in the mitochondrial fraction. Immunohistochemical analysis of SP-22 in normal placenta showed that immunoreactive SP-22 was distributed mostly in cytotrophoblastic cells but with almost no signal in syncytiotrophoblasts. The positive signals were also detected in the decidual cells and stromal cells in stem villi of normal placenta. We also examined LPS-mediated inflammatory placenta on day 13 of pregnancy at various time points after LPS injection (50 microg/kg, intraperitoneally). Western blot analysis indicated that LPS approximately quadrupled the expression of SP-22 in placenta of LPS-exposed mouse. When the SP-22 protein was localized immunohistochemically, the decidua and the diploid trophoblasts in the basal zone were intensively stained in placenta of LPS-exposed mouse compared to the control. The localization and inducible expression of SP-22 protein in placenta suggest a possible role in antioxidant system in mitochondria of normal and inflammatory placentae.     

胎盘乙型肝炎病毒感染与宫内传播的关系

目的 探讨乙型肝炎病毒（ＨＢＶ）宫内传播的危险因素,并追踪ＨＢＶ经胎盘传播的途径和胎儿宫内感染的时间,方法 共收集了乙型肝炎表面抗原（ＨＢｓＡｇ）携带孕妇１３１例,其中孕早期人工流产胎盘２４例,孕中期引产胎盘和胎儿各６例,足月分娩胎盘和新生儿各１０１例。孕妇和新生儿血清ＨＢｓＡｇ和ＨＢＶ ＤＮＡ检测分别采用酶联免疫吸附试验和聚酶链反应法。     

Placental protein 13 and decidual zones of necrosis: an immunologic diversion that may be linked to preeclampsia

We evaluated the role of placental protein 13 (PP13; galectin 13) in the process of trophoblast invasion and decidual necrosis. Immunohistochemical analysis for PP13, immune cells, human placental lactogen, cytokeratin, and apoptosis markers was performed on 20 elective pregnancy termination specimens between 6 and 15 weeks of gestation. Placental protein 13 was localized to syncytiotrophoblasts in the chorionic villi and to occasional multinucleated luminal trophoblasts within converted decidual spiral arterioles. Cytotrophoblasts, anchoring trophoblasts, and invasive trophoblasts did not stain for PP13. Extracellular PP13 aggregates were found around decidual veins associated with T-cell-, neutrophil- and macrophage-containing decidual zones of necrosis (ZONEs). We hypothesize that PP13 is secreted into the intervillus space, drains through the decidua basalis veins, and forms perivenous PP13 aggregates which attract and activate maternal immune cells. Thus, syncytiotrophoblast-derived PP13 may create a ZONE that facilitates trophoblast invasion and conversion of the maternal spiral arterioles.     

Immunoglobulin G in the decidua basalis and metrial gland of the pregnant mouse uterus

The distribution of immunoglobulin G (IgG) in the decidua basalis and metrial gland of the mouse uterus at days 10 and 14 of pregnancy has been investigated using immunohistochemical methods. IgG was found in the intercellular spaces but none was found in decidual cells, stromal cells of the metrial gland or granulated metrial gland cells. These results differ from those of other studies which have localised IgG in the cytoplasm of rat granulated metrial gland cells.     

The effects of cortisol on the binucleate cell population in the ovine placenta during late gestation

Large granulated binucleate cells (BNCs) producing placental lactogen (PL) and pregnancy-associated glycoproteins (PAG) are present in all ruminant placentae throughout pregnancy. These BNC account for 15-20% of the cells in ovine trophectoderm for most of gestation but decrease in number close to term at the same time that fetal cortisol levels rise. The present study investigated the effects of cortisol on the BNC population using immunohistochemistry to count BNCs in ovine placentomes during late gestation and after experimental manipulation of the fetal cortisol level by fetal adrenalectomy and exogenous cortisol infusion. Abolition of the prepartum rise in fetal cortisol prevented the normal decline in BNC numbers towards term. Conversely, raising cortisol levels in immature fetuses to prepartum values prematurely reduced placental BNC numbers. However, a small population of BNC remained, even at the highest cortisol concentrations. When all the data were combined irrespective of treatment or gestational age, there was a significant inverse correlation between fetal plasma cortisol and the number of BNCs in the ovine placenta. These findings show that cortisol regulates the BNC population in ovine placenta during late gestation. They also have important implications for the production of PL and PAG during ovine pregnancy.