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1.
人妊娠期间,胎盘合成大量的类固醇激素,与妊娠的启动、维持、分娩以及胎儿的发育均存在密切的关系。阐明胎盘类固醇激素特别是孕酮合成与分泌的调节机制对于寻找理想的生育调控技术和生殖保健方法具有重要的意义。因此,胎盘类固醇激素合成与分泌的调节向来是生殖生物学与妇产科学领域所关注的焦点问题之一,  相似文献   

2.
Anti-interferon (IFN) activities of normal human sera and sera from cases suspected of viral infection were determined. Of the normal sera tested (57), 65% presented anti-IFN activities against IFN-alpha and/or -beta preparations; 61% against IFN-beta and 32% against IFN-alpha. Of the sera from suspected virus-infected individuals (44), 82% presented anti-IFN activity to IFN-beta and 57% to IFN-alpha with the majority of sera (91%) exerting anti-IFN activities to IFN-alpha and/or -beta preparation. The observed variations of anti-IFN alpha and beta activities of human sera appear to be reproducible and should be taken into consideration in the clinical application of IFN.  相似文献   

3.
人妊娠期间,胎盘合成大量的类固醇激素,与妊娠的启动、维持、分娩以及胎儿的发育均存在密切的关系。阐明胎盘类固醇激素特别是孕酮合成与分泌的调节机制对于寻找理想的生育调控技术和生殖保健方法具有重要的意义。因此,胎盘类固醇激素合成与分泌的调节向来是生殖生物学与妇产科学领域所关注的焦点问题之一,并为此开展了大量的研究,但迄今仍不清楚,其主要原因之一是  相似文献   

4.
胚胎植入和胎盘形成涉及细胞外基质的降解和重建,以及细胞的增殖、凋亡、迁移和分化,基质金属蛋白酶 (MMPs) 是参与这些事件的主要蛋白水解酶系统 . MMP-26 是近年来发现的 MMPs 家族的新成员,但其功能所知甚少 . 通过半定量 RT-PCR 、免疫组织化学、荧光免疫细胞化学等手段,发现人胎盘中 MMP-26 主要定位于绒毛滋养层细胞,在绒毛间质细胞中也有少量表达 . 妊娠早期,胎盘中 MMP-26 表达水平较高,至妊娠中期降至最低,但在足月胎盘中其表达又有显著提高,提示 MMP-26 可能参与妊娠早期滋养层细胞的侵润和分娩时的胎盘剥离 . 体外培养的妊娠早期人细胞滋养层细胞能产生一定水平的 MMP-26 ,而其表达受到激活素 A 的剂量依赖性刺激,表明滋养层细胞中存在 MMP-26 表达的自分泌 / 旁分泌调节 .  相似文献   

5.
Summary The 14 kD S-type lectin from human placenta may have a role in regulating the maternal immune response to fetal antigens. In this study, an immunoperoxidase technique was used to determine the distribution of the lectin at the human maternofetal interface. Tissue obtained during the first trimester of pregnancy and at term was used. The lectin was not detectable in either the villous syncytiotrophoblast or the underlying cytotrophoblast in first-trimester tissue, although some cells of the cytotrophoblast columns were reactive. It was also not detectable in villous or extravillous trophoblast populations at term. In contrast, strong reactivity was found in decidual stromal cells throughout gestation, and endometrial stromal cells were also positive. The lectin is, therefore, not a component of the immunosuppressive factors associated with syncytiotrophoblast membranes, but may have a role in either the decidual control of trophoblast migration or some functions unrelated to pregnancy, or both.  相似文献   

6.
The effect of in vivo administered interferon-alpha (IFN-alpha) on 2-5-oligoadenylate (A) synthetase activity of peripheral blood mononuclear cells (PBMC) was compared in patients with hairy cell leukemia and renal cell cancer. Basic levels of this enzyme varied from donor to donor, but mean levels were not significantly different in patients with renal cell cancer or hairy cell leukemia compared to healthy donors. After a single injection of 3 x 10(6) IU IFN, these basic levels rose 2- to 8-fold within 12-24 h post-injection and reverted to pretreatment levels after 48 h. The extent of this in vivo stimulation by IFN-alpha was similar in patients with hairy cell leukemia and renal cell carcinoma, and was correlated with down-regulation of IFN-alpha receptors. The in vitro effects of IFN-alpha, -beta and -gamma were compared after 18 h treatment with 10, 10(2) and 10(3) IU/ml of each IFN. Unlike IFN-alpha and -beta, IFN-gamma did not induce 2-5 A synthetase activity in either normal PBMC or hairy cells; these results were related to the effects of the three IFN on proliferative response of normal PBMC to phytohemagglutinin. Our data support the idea that 2-5 A synthetase activity is a marker of biological response to interferon treatment in human cancers.  相似文献   

7.
Human ADAM19 is a recently identified member of the ADAM family. It is highly expressed in human placentas, but its dynamic change and function at the human feto-maternal interface during placenta-tion remain to be elucidated. In this present study, the spatial and temporal expression and cellular localization of ADAM19 in normal human placentas were first demonstrated, and the effects of ADAM19 on trophoblast cell adhesion and invasion were further investigated by using a human choriocarcinoma cell line (JEG-3) as an in vitro model. The data demonstrated that ADAM19 was widely distributed in villous cytotrophoblast cells, syncytiotrophoblast cells, column trophoblasts, and villous capillary endothelial cells during early pregnancy. The mRNA and protein level of ADAM19 in placentas was high at gestational weeks 8—9, but diminished significantly at mid- and term pregnancy. In JEG-3 cells, the overexpression of ADAM19 led to diminished cell invasion, as well as increases in cell adhesiveness and the expression of E-cadherin, with no changes in b-catenin expression observed. These data in-dicate that ADAM19 may participate in the coordinated regulation of human trophoblast cell behaviors during the process of placentation.  相似文献   

8.
The effect of pretreatment with interferon (IFN) ('priming') on the production of individual IFN subtypes was studied in subpopulations of human peripheral blood mononuclear cells and in the myeloid cell line KG-1. It was found that priming had a selective enhancing effect on the production of certain IFN-alpha subtypes (IFN-alpha 20K and IFN-alpha 21K) and not on others. KG-1 cells produce both IFN-alpha and -beta; however, only the production of IFN-alpha was enhanced by priming with either IFN-alpha, beta or gamma.  相似文献   

9.
Despite quantitative as well as qualitative differences, all three types of IFN (IFN-alpha, IFN-beta, and IFN-gamma) modulate the synthesis as well as the expression of class I and class II histocompatibility Ag and a melanoma-associated Ag located in the plasma membrane as well as the cytoplasm of human melanoma cells. By employing inhibitors of RNA and protein synthesis it was demonstrated that IFN-alpha and -beta increase the expression of histocompatibility products and this tumor-associated Ag by a process not requiring new protein synthesis. In contrast, IFN-gamma does require de novo protein synthesis for its modulatory activity. Thus, it appears that IFN might trigger various adaptive functions in different cell lineages by inducing at least two separate sets of responses specific for either IFN-alpha and -beta or IFN-gamma. Because the induction requirements for (2'-5')-oligoadenylate synthetase as well as for the development of a cellular antiviral state by different IFN also display a similar protein synthesis dependence pattern, the present results suggest that a similar set of cellular mediators may be involved in the modulation of antigenic expression by IFN-gamma in human melanoma cells.  相似文献   

10.
11.
We recently showed an increase in vascular endothelial growth factor (VEGF), decrease in angiopoietin-1 (Ang-1) and unaltered Ang-2 expression by the villous placenta with advancing baboon pregnancy. Moreover, placental VEGF expression was increased by estrogen in early pregnancy. In the present study, we determined whether placental Ang-1 and Ang-2 are regulated by estrogen. Ang-1 and Ang-2 mRNA and protein were determined by RT-PCR and immunocytochemistry in the placenta of baboons on Day 60 of gestation (term is 184 days) after administration of estrogen precursor androstenedione on Days 25-59 or on Day 54 after acute estradiol administration. Chronic androstenedione treatment increased serum estradiol levels three-fold (P < 0.001) and decreased (P < 0.05) villous cytotrophoblast Ang-1 mRNA to a level (0.36 +/- 0.08 relative to 18S rRNA) that was one-third of that in untreated animals (0.98 +/- 0.26). Within 2 hr of estradiol administration, cytotrophoblast Ang-1 mRNA was decreased to a level (0.24 +/- 0.05) one-fifth (P < 0.05) of that in untreated animals (1.14 +/- 0.23). However, Ang-2 mRNA levels were unaltered. Ang-1, Ang-2 and estrogen receptors alpha and beta protein were localized within villous cytotrophoblasts providing a mechanism for estrogen action at this site. In summary, estrogen increased VEGF, decreased Ang-1, and had no effect on Ang-2 expression within placental cytotrophoblasts during early baboon pregnancy. We propose that the estrogen-dependent differential regulation of these angioregulatory factors underpins the unique pattern of neovascularization established within the villous placenta during primate pregnancy.  相似文献   

12.
SWAP-70 is a unique signaling protein involved in multiple processes including lymphatic cell activation, migration, adhesion, and cytoskeleton organization. Its role in reproductive system remains to be unclear. In the present study, the spatial and temporal expression of SWAP-70 in the uterus during normal menstrual cycle as well as on the feto-maternal interface during pregnancy was investigated in the rhesus monkey by in situ hybridization and immunohistochemistry. It was shown that SWAP-70 was mainly expressed in glandular epithelial cells of uterine endometrium, and the level peaked at the mid-secretory stage. At the beginning of embryonic implantation, SWAP-70 was intensely expressed at the implantation site, mainly localized in glandular and luminal epithelial cells, as well as in primary trophoblasts and epithelial plaque. High level of SWAP-70 was observed in villous cytotrophoblast (VCT), syncytiotrophoblast (ST), column cytotrophoblast, trophoblast shell, interstitial trophoblast, and endovascular trophoblast during gestational days 15–25. From gestational day 50 to term, expression of SWAP-70 decreased evidently and was restricted in VCT cells. What’s more, SWAP-70 co-localized with F-actin on the feto-maternal interface, especially in highly motive extravillous trophoblasts. The data indicate that SWAP-70 may be involved in regulating motility of trophoblast cells during embryonic implantation and placentation.  相似文献   

13.
Eastern equine encephalitis virus (EEEV) causes human encephalitis in North America (NA), but in South America (SA) it has rarely been associated with human disease, suggesting that SA strains are less virulent. To evaluate the hypothesis that this virulence difference is due to a greater ability of NA strains to evade innate immunity, we compared replication of NA and SA strains in Vero cells pretreated with interferon (IFN). Human IFN-alpha, -beta, and -gamma generally exhibited less effect on replication of NA than SA strains, supporting this hypothesis. In the murine model, no consistent difference in IFN induction was observed between NA and SA strains. After infection with most EEEV strains, higher viremia levels and shorter survival times were observed in mice deficient in IFN-alpha/beta receptors than in wild-type mice, suggesting that IFN-alpha/beta is important in controlling replication. In contrast, IFN-gamma receptor-deficient mice infected with NA and SA strains had similar viremia levels and mortality rates to those of wild-type mice, suggesting that IFN-gamma does not play a major role in murine protection. Mice pretreated with poly(I-C), a nonspecific IFN inducer, exhibited dose-dependent protection against fatal eastern equine encephalitis, further evidence that IFN is important in controlling disease. Overall, our in vivo results did not support the hypothesis that NA strains are more virulent in humans due to their greater ability to counteract the IFN response. However, further studies using a better model of human disease are needed to confirm the results of differential human IFN sensitivity obtained in our in vitro experiments.  相似文献   

14.
E-cadherin is a cell–cell adhesion protein expressed in cytotrophoblasts, which is lost as they differentiate and syncytialise. We have exploited E-cadherin as a marker of cytotrophoblasts to investigate villous tissue composition in first and third trimester placentae, both in normal pregnancy and pregnancies complicated by pre-eclampsia. We have achieved this by measuring expression levels of E-cadherin at the mRNA level, using Q-PCR, and at the protein level using semi-quantitative Western blotting. We have also combined E-cadherin immunohistochemistry with morphometric analysis of area measurements to define cytotrophoblast and syncytiotrophoblast compartments. This novel use of E-cadherin has revealed a decrease in the proportion of cytotrophoblasts in villous tissue as pregnancy progresses, in the absence of changes in syncytiotrophoblast cover. Moreover, in pre-eclampsia, placental E-cadherin was raised compared to syncytiotrophoblast, suggesting either exaggerated cytotrophoblast proliferation or impaired cytotrophoblast differentiation, both alterations of potential pathogenic importance.  相似文献   

15.
Traditional first trimester chorionic villus sampling (CVS) for prenatal diagnosis can be performed by cytogenetic analysis of cytotrophoblast or chorionic villous stroma. Approximately 2% of pregnancies studied by CVS show confined placental mosaicism (CPM) involving either cytotrophoblast, stroma or both. We present the results of a cytogenetic study of nine term placentae from pregnancies with prenatally diagnosed CPM. The aneuploid cell lines involved trisomies for chromosomes 7,9,16, and X. The cytotrophoblast and villous stroma from multiple biopsies of these placentae were examined using a combination of interphase and metaphase cytogenetic analysis. CPM was detected in all nine of the term placentae and both tissue-specific and site-specific patterns of mosaicism could be discerned. These results indicate that the analysis of villous stroma and cytotrophoblast from multiple placental biopsies is necessary to improve our understanding of the evolution of CPM during pregnancy and its effect on the fetus. Received: 1 May 1995 / Revised: 11 August 1995  相似文献   

16.
17.
Syncytiotrophoblast and invasive extravillous trophoblast arise from a common stem cell, namely villous cytotrophoblast, but have very different characteristics. The study of the differentiation process relies on the availability of suitable markers for these different cell types of developing placenta. In this work, we have produced monoclonal antibodies that are specific to human villous cytotrophoblast. Monoclonal antibody (MAb) MG2 was specific to villous cytotrophoblast across gestation, and recognizes hepatocyte growth factor activator inhibitor type 1. MAb MD10 stained villous cytotrophoblast across gestation and also some endothelial cells, particularly in the second or third trimester. MAb MD10 recognizes human integrin alpha6beta4. As a test for specificity, the novel MAbs were also used for staining of frozen tissue from human colon carcinoma. The results show that the two antibodies can be used as tools to study human villous cytotrophoblasts and also human tumors. The MG2 antibody seems most specific and promising for the study of various aspects of human villous cytotrophoblast.  相似文献   

18.
Recombinant interferons (IFN-alpha, -beta, and -gamma) were examined for their effects on B cell activation. Relatively small IgM+ B cells from human blood samples were isolated by fluorescence-activated cell sorting and were used as target cells. Although the interferons themselves were nonmitogenic, each enhanced the proliferative response induced by a mitogenic anti-mu monoclonal antibody, with IFN-beta usually showing the greatest enhancement and IFN-gamma the least. Pretreatment with the interferons primed resting B cells to undergo enhanced DNA synthesis in response to the anti-mu antibody DA4. Conversely, anti-mu pretreatment, followed by IFN treatment, did not induce B cells to enter the S phase. Time-course analysis revealed that IFN could augment the anti-mu response even when added as late as the final 24 hr of a 3-day culture interval. Combinations of IFN-gamma plus IFN-alpha or -beta were synergistic in the anti-mu response, whereas the IFN-alpha plus IFN-beta combination was not. The data suggest that interferons produced by both lymphocytes (IFN-gamma) and nonlymphoid inflammatory cells (IFN-alpha and -beta) can enhance B cell growth via different mechanisms.  相似文献   

19.
The antigenic determinant recognized by the monoclonal antibody that had been raised against synthetic human interferon-alpha 1 (IFN-alpha 1) fragment 111-166 [Arnheiter, H., Thomas, R.M., Leist, T., Fountoulakis, M., and Gutte, B. (1981) Nature (Lond.) 294, 278-280] and that cross-reacted with human IFN-alpha 1, IFN-alpha 2, and IFN-alpha A made in Escherichia coli, was localized to the region between residues 151 and 166 using synthetic COOH-terminal interferon fragments. In solid-phase radioimmunoassays neither the strongly hydrophilic COOH-terminal nonapeptide IFN 158-166 nor its mixtures with IFN 151-162 or IFN 149-158 showed any measurable interaction with the antigen binding site of the monoclonal antibody. For antibody binding, the full covalent structure of IFN 151-166 was required. Quantitatively very similar results were obtained with IFN 149-166 and IFN 143-166. The synthetic COOH-terminal hexadecapeptide of human IFN-alpha 1 (IFN 151-166) could be crystallized.  相似文献   

20.
Raf kinase inhibitor protein (RKIP) regulates growth and differentiation signaling of mitogen-activated protein kinases (MAPK), GRK2 and NF-kappaB pathways each of which regulates cytotrophoblast differentiation and normal placental development. We show here that RKIP is expressed in human normal and preeclampic placentas as detected by immunostaining. RKIP was detected in villous cytotrophoblast in normal placenta and switched to syncytiotrophoblast in pre-eclampsia (PE)-complicated pregnancies. RKIP was also localized in extravillous cytotrophoblast of cell islands and cell columns both in normal and in PE placentas, although staining was less uniform in the latter specimens. In order to test RKIP involvement in cytotrophoblast function, we performed in vitro studies on HTR-8/SVneo cells, a first trimester cytotrophoblast cell line. We show that the RKIP inhibitor locostatin reduces ERK phosphorylation and impairs HTR-8/SV neo cells motility in wound closure experiments. We also document the presence of GRK2 mRNA, the reduction of phosphorylated RKIP expression by locostatin and the induction of PAI mRNA expression in HTR-8/SV neo cells, suggesting the involvement of GRK2 and NF-kappaB pathways in these cells. In conclusion, our work provides evidence that RKIP is a novel factor expressed in cytotrophoblast cells where it likely regulates cell migration.  相似文献   

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