Submucosal connective tissue-type mast cells contribute to the production of lysophosphatidic acid (LPA) in the gastrointestinal tract through the secretion of autotaxin (ATX)/lysophospholipase D (lysoPLD)

Lysophosphatidic acid (LPA) is involved in a broad spectrum of biological activities, including wound healing and cancer metastasis. Autotaxin (ATX), originally isolated from a melanoma supernatant as a tumor cell motility-stimulating factor, has been shown to be molecularly identical to lysophospholipase D (lysoPLD), which is the main enzyme in the production of LPA. Although ATX/lysoPLD is known to be widely expressed in normal human tissues, the exact distribution of ATX-producing cells has not been fully investigated. In this study, we evaluated ATX/lysoPLD expression by immunohistochemical staining using a rat anti-ATX mAb in the human gastrointestinal tract and found that submucosal mast cells (MC) highly expressed this enzyme. This was confirmed by immunofluorescent double staining using mAbs to tryptase and chymase. Then, we isolated MC from human gastric tissue by an immunomagnetic method using CD117-microbeads and showed that a subpopulation of CD203c-positive MC showed positive staining for intracellular ATX/lysoPLD on flowcytometry. This was confirmed by Western blotting of the isolated cells. Moreover, a significant level of ATX/lysoPLD release could be detected in the culture supernatants of human MC by Western blot analysis. Our data suggest that submucosal MC play significant roles in various aspects of pathophysiology in the gastrointestinal tract by locally providing bioactive LPA through the production of ATX/lysoPLD.     

基质金属蛋白酶-9和血管内皮生长因子在子痫前期患者胎盘组织中的表达

目的 检测子痫前期患者胎盘组织中RECK、基质金属蛋白酶-9（MMP-9）、血管内皮生长因子（VEGF）的基因表达,探讨它们与胎盘滋养细胞浸润过程的调控关系。 方法 采用RT-PCR、Western blotting、免疫组织化学检测120例妊娠足月剖宫产（正常妊娠、轻度子痫前期、中度子痫前期、重度子痫前期各30例）胎盘组织中RECK、MMP-9、VEGF的基因表达。结果 3组子痫前期患者胎盘组织中MMP-9及VEGF的mRNA表达水平均显著低于正常妊娠组（P<0.05）;重度子痫前期组中RECK mRNA的表达显著高于正常妊娠组（P<0.05）;3组子痫前期患者胎盘组织中MMP-9及VEGF蛋白表达均显著低于正常妊娠组（P<0.05）,中度和重度子痫前期组中RECK蛋白表达显著高于正常妊娠组（P<0.05）。结论 子痫前期患者胎盘中RECK与MMP-9、VEGF之间存在负相关性,它们可能参与了胎盘滋养细胞浅浸润过程的调控。     

The expression and localization of neutral endopeptidase 24.11/CD10 in human gestational trophoblastic diseases

Neutral endopeptidase 24.11 (NEP)/CD10 is a cell-surface peptidase that hydrolyzes various bioactive peptides. NEP is distributed in both normal and neoplastic cells and plays a functional role by modulating cellular responses to peptide substrates. Recently, NEP has been shown to be expressed in normal placental trophoblasts, suggesting its physiological role during pregnancy. In the present study, we investigated the expression of NEP in hyperplastic and anaplastic trophoblasts in gestational trophoblastic diseases (GTDs). Flow cytometric analysis demonstrated that NEP was expressed in all choriocarcinoma cell lines examined. The NEP enzyme activity in these cell lines correlated with cell-surface protein levels and was abolished by the NEP inhibitor phosphoramidon. On immunoblot analysis, NEP protein was detected in both hydatidiform mole and choriocarcinoma tissues as a double band of 95 and 100 kDa similar to that of the normal placental tissues. Immunohistochemical analysis revealed that NEP was present on syncytiotrophoblasts, while no or very faint NEP immunoreactivity was observed on cytotrophoblasts in the normal placenta. Similarly, NEP in hydatidiform mole and invasive mole was localized on the membrane of syncytiotrophoblasts, but not on hyperplastic cytotrophoblasts. In contrast, in choriocarcinoma, NEP was highly expressed not only on syncytiotrophoblastic cells but also on invading anaplastic cytotrophoblasts. In addition, NEP was also expressed on intermediate trophoblasts in placental site trophoblastic tumors. In summary, this is the first study demonstrating the expression of NEP/CD10 in GTDs. The differential localization of NEP among various trophoblastic tumors suggests that NEP may play a functional role in the regulation of trophoblast transformation and human chorionic gonadotropin secretion.     

Bcl—2蛋白在正常、妊高征及胎儿宫内发育迟缓胎盘中的表达

目的 通过检测Bcl-2蛋白在正常各期胎盘、妊高征胎盘和胎儿宫内发育迟缓胎盘中的表达，探讨Bcl-2蛋白在胎盘的发育过程中的功能及妊高征和胎儿宫内发育迟缓的病理机制。方法 取正常的8－10周、20－22周、足月胎盘以及妊高征和胎儿宫内发育迟结的胎盘组织固定，石蜡包坦，用ABC法抗Bcl-2免疫组织化学染色，光镜观察。结果 正常早孕绒毛合体细胞滋养怪、细胞滋养层细胞核、绒毛吵轴细胞阳性，细胞滋养层的胞质、绒毛中轴基质阴性。正常中期和足月胎盘滋养层细胞、血管内皮细胞阳性。与正常足月胎盘相比，妊高征、台儿宫内发育迟缓胎盘几科不着色。结论 Bcl-2蛋白在正常各期胎盘中均有表达，而在妊高征和胎儿宫内发育迟缓胎盘几乎不表达，Bcl-2蛋白表达异常与妊高征与胎儿宫内发育迟缓的发病机制有关。     

Altered Expression of Human Leukocyte Antigen G (HLA-G) on Extravillous Trophoblasts in Preeclampsia: Immunohistological Demonstration With Anti-HLA-G Specific Antibody “87G” and Anti-cytokeratin Antibody “CAM5.2”

PROBLEM: Human leukocyte antigen-G (HLA-G) is suggested to be at play in the materno-fetal immune relationship during pregnancy. In the light of current concept that disruption of the materno-fetal immune relationship could account for several complications of pregnancy, including preeclampsia, we asked whether the expression of HLA-G protein on the trophoblasts is altered in preeclampsia. METHOD: The presence of HLA-G protein in the extravillous trophoblasts in placenta obtained from five preeclamptic patients and seven uncomplicated pregnant women was determined by means of an immunohistochemical technique. RESULTS: All of the extravillous trophoblasts, which were stained for cytokeratin, were stained for HLA-G protein in every woman with an uncomplicated pregnancy. In contrast, clusters of extravillous trophoblasts were insularly devoid of the staining for HLA-G in all the preeclamptic patients. CONCLUSION: The attenuated expression of HLA-G protein on the extravillous trophoblasts could be at play in the pathophysiology of preeclampsia.     

Expression of interleukin-1beta mRNA in murine uterine and gestational tissues: relationship with gestational age.

PROBLEM: The pro-inflammatory cytokine interleukin (IL)-1beta has been shown to stimulate the production of prostaglandins (PG) in gestational tissues. Increased PG synthesis is considered a key step in the initiation of labor both at term and preterm. In this study. IL-1beta mRNA in the uterus and gestational tissues of mice during mid to late pregnancy was studied to characterize its tissue specific as well as gestational age expression. METHOD OF STUDY: Gestational tissues (placenta. decidual cap and fetal membranes). uterus, and cervix were collected from pregnant mice during gestation. Total RNA was isolated and probed for the expression of IL-1beta mRNA. RESULTS: There was a significantly increased expression of IL-1beta mRNA in the uterus on day 18 of pregnancy. In the decidual caps, there was increased expression of IL-1beta mRNA on day 14 of pregnancy and a decrease in expression with the onset of labor. In the fetal membranes and placenta, IL-1beta mRNA expression significantly increased on days 14 and 18 of pregnancy. respectively, and then remained elevated for the duration of pregnancy. In the cervix, there was a decrease in expression with labor onset. CONCLUSIONS: The increases in IL-1beta mRNA in the fetal membranes and placenta late in pregnancy are consistent with a localized, tissue specific inflammatory activation involved in the initiation of parturition.     

正常妊娠及妊娠期糖尿病患者血脂代谢特点

目的观察妊娠期糖尿病（gestational diabetes mellitus,GDM）孕妇和正常妊娠孕妇不同孕期的血脂代谢特点,探讨妊娠早中期血脂变化与GDM的关系。方法选择在我院门诊就诊的正常健康孕妇（A组）及GDM孕妇（B组）,两组分别于孕14-19周、28-34周抽取空腹静脉血测定血浆总胆固醇（TC）、甘油三脂（TG）、高密度脂蛋白（HDL）、低密度脂蛋白（LDL）、载脂蛋白AI（APOAI）、载脂蛋白B（APOB）、脂蛋白A（LPA）。结果 （1）正常妊娠组与GDM组孕妇随着孕周的增加,TC、TG、APOB、LDL值显著升高（P〈0.01）,APOAI值明显升高（P〈0.05）,正常妊娠组中LPA值随孕周增加明显升高（P〈0.05）;（2）GDM组孕妇在孕14-19周及孕28-34周,TG值较同孕周的正常妊娠组显著升高（P〈0.01）,APOB值在GDM组孕14-19周时明显高于同期正常妊娠组（P〈0.01）;（3）TC、LDL、HDL、APOAI、LPA在两组不同孕周间比较均无显著性差异（P〉0.05）,HDL值随两组孕周增加升高不明显（P〉0.05）。结论GDM孕妇在不同孕周的甘油三酯水平均高于正常妊娠孕妇;GDM孕妇在孕早中期较正常妊娠孕妇存在更早期、更明显的脂代谢紊乱。在孕早中期监测血糖、血脂水平,及时制定合理的饮食计划,可减少GDM的发生和尽早防治其可能带来的母婴危害。     

6Human trophoblast: Development of double tissue confrontation assays

Problem:  Invasion of trophoblast differs between implantation and subsequent placentation. Here we present double tissue co-culture in vitro models for trophoblast invasion.
Material and Methods:  Pieces of decidua parietalis (6-12 weeks gestation) were confronted directly with villous explants (direct confrontation) or after separate preculture for 72h (indirect confrontation). For "indirect confrontation" decidua pieces re-epithelialized during preculture (constant agitation). All confrontations were harvested after 72h and were processed for immunohistochemistry.
Results:  During indirect confrontation immunohistochemical staining for HLA-G and cytokeratin 7 revealed trophoblast migration on top of the decidual epithelium and little invasion into the decidual stroma. During direct confrontation, the same staining revealed strong invasion of extravillous trophoblasts into decidual stroma.
Conclusion:  Trophoblasts confronted to decidual epithelium seem to be less invasive than trophoblasts confronted to the decidual stroma directly. These model systems will be further used to investigate mechanisms underlying the interactions between trophoblasts and decidual epithelium/stroma.     

CD147在不明原因自然流产患者绒毛组织的表达

目的:分析CD147在不明原因自然流产患者绒毛组织中的表达水平,并探讨其生物学功能。方法:收集人早孕期正常和不明原因自然流产妇女的绒毛组织,采用免疫组织化学、RT-PCR和Western blotting法检测CD147的表达,比较CD147在正常早孕与不明原因自然流产妇女绒毛组织的表达差异。体外分离纯化获得正常人早孕期滋养细胞,采用免疫细胞化学验证CD147在滋养细胞的表达,引入抗CD147中和性抗体处理人滋养细胞,采用Brd U增殖实验和Transwell侵袭实验分析滋养细胞增殖和侵袭能力的变化。结果:正常早孕期绒毛组织和滋养细胞高表达CD147,不明原因自然流产绒毛组织CD147的mRNA和蛋白表达水平均低于正常早孕期绒毛组织。抗CD147中和性抗体处理原代人滋养细胞后,滋养细胞的增殖能力未发生明显变化,侵袭能力下降。结论:人绒毛组织CD147的异常低表达可能与不明原因早期妊娠失败相关,CD147通过调控滋养细胞的侵袭能力参与正常妊娠的维持。     

Expression, localization, and function of MRP5 (ABCC5), a transporter for cyclic nucleotides, in human placenta and cultured human trophoblasts: effects of gestational age and cellular differentiation

The placenta functions both as site for nutrition and protection of the fetus. Transport proteins, including members of the multidrug resistance protein (MRP)/ABCC subfamily, have been recognized to contribute to the latter function. MRP5 (ABCC5) was identified as transmembrane transport protein for cyclic nucleotides, especially 3',5'-cyclic GMP (cGMP), indicating an additional role in signal transduction and a potential role in placenta development. We therefore studied expression, localization, and function of MRP5 in placenta of different gestational ages. Quantitative real-time polymerase chain reaction revealed expression of MRP5 in all 60 samples from pre-term and term placenta, with a decreasing mean expression with gestational age (MRP5/18S-ratio x 1000; < 32 weeks: 2.91 +/- 0.73, n = 15; 32 to 37 weeks: 2.10 +/- 0.87, n = 15; > 37 weeks: 0.46 +/- 0.08, n = 30; P < 0.01). Immunofluorescence microscopy with an anti-MRP5 antibody indicated localization of MRP5 preferentially in the basal membrane of syncytiotrophoblasts and in and around fetal vessels. ATP-dependent [(3)H]cGMP transport as evidence for MRP5 function could be demonstrated in isolated basal membrane vesicles. Moreover, the influence of cellular differentiation on MRP5 expression was studied in isolated trophoblasts, revealing an increase of the MRP5 expression in parallel with the hCG production (MRP5/18S-ratio x 1000 was 2.4 +/- 0.5 at day 5 of culture and 1.45 +/- 0.5 at day 0 of culture, n = 3 preparations, significant difference with P < 0.05). In conclusion, MRP5 expression depends on gestational age and varies throughout the differentiation process. In view of the important role of cGMP for cellular differentiation, MRP5 may play a role in placental development in context with a specific need for cellular cGMP export.     

HIV-1协同受体CXCR4、CCR5及相关趋化因子SDF-1在胎盘的表达

目的：研究HIV-1协同受体CXCR4、CCR5及CXCR4的特异性配体SDF-1在人胎盘组织的表达，探索HIV-1子宫内垂直传播的分子机制。方法：半定量RT-PCR检测早、中、晚孕期胎盘及早孕滋养细胞CXCR4、CCR5 mRNA水平；免疫组化和免疫细胞化学检测早孕胎盘及原代培养滋养细胞CXCR4、CCR5蛋白表达；原位杂交及免疫组化分析SDF-1在早孕胎盘的表达；ELISA测定滋养细胞SDF-1的动态分泌水平。结果：各孕期胎盘表达CXCR4及CCR5 mRNA；CXCR4蛋白定位于滋养细胞，而CCR5蛋白定位于绒毛基质中。滋养细胞可转录并翻译SDF-1，且能分泌可溶性SDF-1。结论：滋养细胞同时表达CXCR4及SDF-1，SDF-1可能通过降调CXCR4而拮抗X4-HIV-1感染胎儿细胞；R5-HIV-1或许能通过滋养层裂隙感染CCR5^#基质细胞和/或Hotbauer细胞，从而发生子宫内垂直传播。     

妊娠早期绒毛及中晚期胎盘中Ghrelin的表达研究

目的探讨明确ghrelin是否参与了妊娠胎盘形成发育及胚胎早期发育进程。方法本研究利用免疫组化和实时定量RT—PCR技术检测了人妊娠早期绒毛及中晚期胎盘ghrelin蛋白的表达定位和ghrelin mRNA水平相对表达变化规律。结果免疫组化结果表明，ghrelin蛋白主要分布于滋养层细胞和血管内皮细胞；实时定量RT—PCR结果揭示人妊娠早期绒毛及中晚期胎盘ghrelin mRNA的相对表达量依据发育阶段的不同而呈现一定变化规律，即在妊娠早期6、7、8周显著高于12—15周胎盘（P〈0．05），16周表达量又出现上升趋势。在晚期胚胎中ghrelin表达明显下降。结论妊娠早期绒毛和中晚期胎盘中ghrelin蛋白的表达及ghrelin mRNA特定的表达模式，揭示这一新型分子在人妊娠早期绒毛形成及中晚期胎盘发育过程中具有潜在的调控作用。     

缺氧诱导因子1α在妊高征和正常妊娠胎盘组织中的差异表达

目的:探讨缺氧诱导因子1α(HIF-1α)蛋白及其mRNA在妊高征和正常妊娠胎盘组织中的表达的差异。方法:应用Westernblot检测10例妊高征和10例年龄匹配的正常妊娠的胎盘组织中HIF-1α蛋白表达的水平;应用实时定量PCR,检测两种组织中HIF-1αmRNA表达的水平。结果:与正常妊娠胎盘组织相比较,妊高征胎盘组织中HIF-1α蛋白和mRNA的表达水平明显增加(P<0.05)。结论:HIF-1α在妊高征胎盘组织中表达增高,可能与妊高征的病因及病理生理有关。     

Expression of Epstein-Barr Virus-Induced Gene 3, an Interleukin-12 p40-Related Molecule, throughout Human Pregnancy : Involvement of Syncytiotrophoblasts and Extravillous Trophoblasts

In human pregnancy, trophoblasts are the only cells of fetal origin in direct contact with the maternal immune system: syncytiotrophoblasts are in contact with maternal blood, whereas extravillous trophoblasts are in contact with numerous maternal uterine natural killer (NK) cells. Therefore, trophoblasts are thought to play a key role in maternal tolerance to the semiallogeneic fetus, in part through cytokine production and NK cell interaction. Epstein-Barr virus-induced gene 3 (EBI3) encodes a soluble hematopoietin receptor related to the p40 subunit of interleukin-12. Previous studies indicated that EBI3 is expressed in the spleen and tonsils, and at high levels in full-term placenta. To investigate further EBI3 expression throughout human pregnancy, we generated monoclonal antibodies specific for EBI3 and developed an EBI3 enzyme-linked immunosorbent assay. Immunohistochemical experiments with EBI3 monoclonal antibody on first-, second-, and third-trimester placental tissues demonstrated that EBI3 was expressed throughout pregnancy by syncytiotrophoblasts and extravillous trophoblasts (cytotrophoblast cell columns, interstitial trophoblasts, multinucleated giant cells, and trophoblasts of the chorion laeve). EBI3 expression was also induced during in vitro differentiation of trophoblast cell lines. In addition, large amounts of secreted EBI3 were detected in explant cultures from first-trimester and term placentae. Consistent with these data, EBI3 levels were strongly up-regulated in sera from pregnant women and gradually increased with gestational age. These data, together with the finding that EBI3 peptide is presented by HLA-G, suggest that EBI3 is an important immunomodulator in the fetal-maternal relationship, possibly involved in NK cell regulation.     

Schistosome Egg Antigens Elicit a Proinflammatory Response by Trophoblast Cells of the Human Placenta

Schistosomiasis affects nearly 40 million women of reproductive age. Many of these women are infected while pregnant and lactating. Several studies have demonstrated transplacental trafficking of schistosome antigens; however, little is known regarding how these antigens affect the developing fetus and placenta. To evaluate the impact of schistosomiasis on trophoblasts of the human placenta, we isolated primary trophoblast cells from healthy placentas delivered at term. These trophoblasts were placed in culture and treated with Schistosoma japonicum soluble egg antigens (SEA) or plasma from S. japonicum-infected pregnant women. Outcomes measured included cytokine production and activation of signal transduction pathways. Treatment of primary human trophoblast cells with SEA resulted in upregulation of the proinflammatory cytokines interleukin 6 (IL-6) and IL-8 and the chemokine macrophage inflammatory protein 1α (MIP-1α). Cytokine production in response to SEA was dose dependent and reminiscent of production in response to other proinflammatory stimuli, such as Toll-like receptor 2 (TLR2) and TLR4 agonists. In addition, the signaling pathways extracellular signal-regulated kinase 1/2 (ERK1/2), Jun N-terminal protein kinase (JNK), p38, and NF-κB were all activated by SEA in primary trophoblasts. These effects appeared to be mediated through both carbohydrate and protein epitopes of SEA. Finally, primary trophoblasts cocultured with plasma from S. japonicum-infected pregnant women produced increased levels of IL-8 compared to trophoblasts cocultured with plasma from uninfected pregnant women. We report here a direct impact of SEA on primary human trophoblast cells, which are critical for many aspects of a healthy pregnancy. Our data indicate that schistosome antigens can activate proinflammatory responses in trophoblasts, which might compromise maternal-fetal health in pregnancies complicated by schistosomiasis.     

Expression of placental leucine aminopeptidase and adipocyte-derived leucine aminopeptidase in human normal and malignant invasive trophoblastic cells

We recently identified two novel aminopeptidases, placental leucine aminopeptidase (P-LAP) and adipocyte-derived leucine aminopeptidase (A-LAP). Enzymatically, P-LAP degrades oxytocin, vasopressin, and angiotensin III, while A-LAP degrades angiotensin II and kallidin. In this study we investigated the expression and localization of P-LAP and A-LAP in human trophoblastic cells in the normal placenta (n = 26), gestational choriocarcinoma (n = 8), and placental site trophoblastic tumor (n = 3). On immunoblot analysis both P-LAP and A-LAP proteins were detected in normal placenta and five choriocarcinoma tissues, as well as in two choriocarcinoma cell lines. Immunohistochemical staining of normal placental tissues demonstrated that P-LAP was not only localized in villous syncytiotrophoblasts but also highly expressed in extravillous trophoblasts (EVTs) invading the decidua or maternal spiral arteries. The expression level of P-LAP on these invasive EVTs reached a maximum during the late first to second trimesters of pregnancy, and it decreased in the third trimester. Similarly, A-LAP was strongly expressed in EVTs invading the decidua or spiral arteries in the second trimester of pregnancy, while it was weakly or moderately expressed in villous cytotrophoblasts or EVTs located in the cell columns. These two aminopeptidases were more strongly expressed in all eight choriocarcinomas and three placental site trophoblastic tumors and mainly localized to the intermediate-type trophoblastic tumor cells invading the uterine myometrium or stromal vessels. In summary P-LAP and A-LAP were predominantly expressed in the invasive phenotype of EVTs during placentation, as well as in the invasive tumor cells of trophoblastic neoplasms. These results suggest the involvement of these aminopeptidases in invasiveness of both normal and malignant intermediate-type trophoblasts possibly through degradation of specific peptide substrates.