A study of various properties of beta-galactocerebrosidase from human chorion using synthetic fluorescent substrates

The properties of beta-galactocerebrosidase from human chorionic villi, cultured chorionic villi and cultured skin fibroblasts were compared, using 6-hexadecanoylamino-4-methylumbelliferyl-beta-D-galactopyranoside (HMGaL) as substrate. The effects of bile salt and Triton X-100 on beta-galactocerebrosidase were examined. It was shown that optimization of the HMGaL assay system requires the presence of pure sodium taurocholate and Triton X-100 at concentrations of 4.5 mM and 0.28 mM, respectively. The optimal pH value was found to be equal to 4.5-5.0; Km for the substrate was 0.03 mM. A comparison of beta-galactocerebrosidase from chorionic villi and cultured chorionic villi with the enzyme from skin fibroblasts revealed the similarity of some properties of these enzymes. The experimental results suggest that HMGaL can be used as a substrate for the identification of chorionic villi beta-galactocerebrosidase in an early prenatal diagnosis of Krabbe's disease.     

First trimester prenatal diagnosis of adrenoleukodystrophy by determination of very long chain fatty acid levels and by linkage analysis to a DNA probe

Summary A first trimester prenatal diagnosis of adrenoleukodystrophy has been done on chorionic villi biopsy in the pregnancy of a carrier woman. Two different approaches allowed one to determine that the male fetus was affected: the linkage analysis of DNA from chorionic villi using the highly polymorphic probe St 14 and the determination of very long chain fatty acid levels in cultured chorionic villi.     

229例流产绒毛染色体核型分析及两种长期培养方法比较

目的:探讨早期自然流产绒毛染色体核型分析在自然流产病因检测中的应用价值,并比较两种长期培养方法的差别。方法:选择孕早期自然流产的孕妇229例,在无菌条件下,从宫腔内取出绒毛,同时或单独经胰酶消化法与切碎贴壁法进行细胞培养,传代之后常规进行G显带,在显微镜下做核型分析。结果:229例流产胎儿绒毛,培养成功206例,成功率为89.96%。异常核型105例,异常率为50.97%,数目异常者101例,占异常核型的96.19%,以16三体最为多见。胰酶消化法的培养成功率及收获时间都显著优于直接贴壁法,差异具有统计学意义(P0.05)。结论:自然流产绒毛染色体核型分析对流产查因具有实用价值。胰酶消化法较切碎贴壁法对流产绒毛长期培养及染色体核型分析更具实用性。     

Features of the histotopography of proteins in human chorionic and placental tissues at different stages of normal and pathologic development

Contents of total, basic and acidic proteins have been studied in the human chorionic tunic at successive stages of a normal embryogenesis and at certain types of pathological pregnancy by means of histochemical methods. According to the staining degree, there is certain heterogeneity of the villi at various differentiation levels. An essential decrease in intensity of histochemical reactions is revealed in the chorionic villi at stillbirth and tetania gravidatum. The peculiarities in histotopography of the proteins and aminoacids studied reflect principle histochemical and structural reconstructions of the chorionic villi at various stages of normal and pathological pregnancy.     

Beta-mannosidase of trophoblast and humana skin fibroblasts]

Conditions for assay of beta-mannosidase activity in human chorionic villi were studied using the fluorogenic substrate 4-methylumbelliferyl-beta-D-mannopyranoside. Comparison of the biochemical properties of the chorionic villi beta-mannosidase with those of the enzyme from human cultured fibroblasts showed their similarity. Like the enzyme from skin fibroblasts, the chorionic villi beta-mannosidase had rather high activity. Both enzymes had virtually the same pH optimum (4.2-4.7) and Km value. The data presented suggest that chorion biopsy specimens can be used for prenatal determination of beta-mannosidase activity at the early stage of development.     

Implications of the placental structure compatibility for interspecies embryo transfer

Comparative histological features of the chorionic villi in placental cotyledons of the common eland (Taurotragus oryx ) and bongo (Boocercus euryceros ) antelopes and okapi (Okapia johnstoni ) and giraffe (Giraffa camelopardalis ) were examined. The chorionic villi in both antelope species showed only moderate branching and/or surface corrugation and their cross-sections were polygonal to oval. The close similarity in the structure of cotyledons has been apparently a contributing factor for success in mutual interspecies embryo transfer. The chorionic villi in okapi and giraffe had very different structures. In okapi the villi on cross-section were round and filled with thin connective tissue. They showed minimal branching and surface corrugation. In giraffe the villi showed extensive surface corrugation, had multiple fine branches, and were filled with a more dense connective tissue. Prospect for materno-fetal compatibility in mutual embryo transfer between these species is guarded.     

Chorionic villi sampling: cytogenetic and clinical findings in 500 pregnancies.

The cytogenetic findings were analysed in a series of 500 pregnancies in which chorionic villi sampling was performed. In all cases a direct method was used, karyotyping being successful in 481 cases (96.2%). The main indication for sampling was maternal age over 36 (412 cases; 82.4%). Abnormal laboratory findings resulted in 24 terminations of pregnancy (4.8%); in addition five unexpected balanced chromosome rearrangements were detected. Twelve of 15 cytogenetic discrepancies were detected at amniocentesis, two after termination, and one at spontaneous abortion. Complete follow up data were available for the first 250 patients, among whom nine pregnancies (3.6%) ended in spontaneous abortion before the 20th week. There were no false negative findings. Seventy additional chromosome studies were performed because of failure of chorionic villi sampling or equivocal results, or for confirmation. Counselling before chorionic villi sampling should include the possibility that subsequent amniocentesis may be needed should mosaicism or other unexpected abnormalities be found. The success rate and accuracy of karyotyping chorionic villi samples by the direct method are acceptable but distinctly less than those of karyotyping cultured amniotic fluid cells.     

Relationship between tissue damage and heme oxygenase expression in chorionic villi of term human placenta

Heme oxygenase (HO) catalyzes the oxidation of heme to carbon monoxide (CO), biliverdin, and iron and is thought to play a role in protecting tissues from oxidative damage. There are three isoforms of HO: HO-1 (inducible), HO-2 (constitutive), and HO-3 (unknown function). Preeclampsia is characterized by an inadequately perfused placenta and areas of tissue damage. We hypothesized that damaged areas of placentas from women with PE and uncomplicated pregnancies are associated with an alteration in HO expression. Compared with microsomes isolated from morphologically normal and peri-infarct chorionic villi of pathological placentas, microsomes from infarcted chorionic villi from the same placentas had decreased HO activity measured under optimized assay conditions. There was no correlation between microsomal HO levels and activity and tissue damage in uncomplicated pregnancies. Whereas there was no significant difference in HO-1 protein levels across all regions of uncomplicated and mildly preeclamptic pregnancies, HO-2 protein levels were decreased (P < 0.05) in peri-infarct regions and infarcted chorionic villi of mildly preeclamptic pregnancies. Immunohistochemical analysis revealed an apparent decrease in both HO-1 and HO-2 protein expression in damaged tissues. HO-1 and HO-2 were immunolocalized in the syncytiotrophoblast layer of the chorionic villi, the underlying cytotrophoblast, and in the vascular endothelium. This study suggests that the ability of the chorionic villi to oxidize heme to CO, biliverdin, and iron may be compromised in areas of tissue damage in the placenta of women with preeclampsia.     

First-trimester prenatal diagnosis of Tay-Sachs disease.

The prenatal diagnosis of Tay-Sachs disease was made in two at-risk fetuses by the analysis of chorionic villi obtained at 9 and 11 menstrual weeks, respectively. The diagnoses were based on the absence of beta-hexosaminidase A activity as determined by: (1) specific enzyme assays, (2) anion-exchange chromatography, and (3) cellulose acetate gel electrophoresis. The enzymatic diagnoses were confirmed on fetal tissue as well as by ultrastructural demonstration of the first-trimester fetal neuropathology. Optimal assay conditions for beta-hexosaminidase A in chorionic villi were established for the prenatal diagnosis of Tay-Sachs disease. Importantly, it was noted that a small amount of decidua or maternal blood could lead to misdiagnosis. Thus, extreme care must be taken in the preparation of chorionic villi for Tay-Sachs as well as other prenatal metabolic diagnoses.     

Human cytomegalovirus infection of placental cytotrophoblasts in vitro and in utero: implications for transmission and pathogenesis

Human cytomegalovirus (CMV) is the leading cause of prenatal viral infection. Affected infants may suffer intrauterine growth retardation and serious neurologic impairment. Analysis of spontaneously aborted conceptuses shows that CMV infects the placenta before the embryo or fetus. In the human hemochorial placenta, maternal blood directly contacts syncytiotrophoblasts that cover chorionic villi and cytotrophoblasts that invade uterine vessels, suggesting possible routes for CMV transmission. To test this hypothesis, we exposed first-trimester chorionic villi and isolated cytotrophoblasts to CMV in vitro. In chorionic villi, syncytiotrophoblasts did not become infected, although clusters of underlying cytotrophoblasts expressed viral proteins. In chorionic villi that were infected with CMV in utero, syncytiotrophoblasts were often spared, whereas cytotrophoblasts and other cells of the villous core expressed viral proteins. Isolated cytotrophoblasts were also permissive for CMV replication in vitro; significantly, infection subsequently impaired the cytotrophoblasts' ability to differentiate and invade. These results suggest two possible routes of CMV transmission to the fetus: (i) across syncytiotrophoblasts with subsequent infection of the underlying cytotrophoblasts and (ii) via invasive cytotrophoblasts within the uterine wall. Furthermore, the observation that CMV infection impairs critical aspects of cytotrophoblast function offers testable hypotheses for explaining the deleterious effects of this virus on pregnancy outcome.     

Lysosomal hydrolase activity in chorionic villi and embryonic cells in culture

Summary Fourteen lysosomal enzymes were compared in 20 cultured cell lines from chorionic biopsy and corresponding embryonic tissue after voluntary abortions. Enzymatic expression appears to be similar in cultured cells from both sources with some slightly higher levels for chorionic villi. We stress the importance of culturing chorionic villi especially in the case of enzymes (-L-iduronidase) or diseases (I cell disease) whose expression is unusual in fresh trophoblast tissue.     

Prenatal diagnosis of a true fetal tetraploidy in direct and cultured chorionic villi

Prenatal diagnosis of a true fetal tetraploidy in direct and cultured chorionic villi: Tetraploidy is characterized by four complete sets of chromosomes (4n= 92). Although it has been frequently reported in spontaneous abortions, tetraploidy is extremely rare in term pregnancy. Most of late surviving patients are diploid/tetraploid mosaics and present severe mental and physical impairment. Up to date, only five tetraploidies were ascertained in the prenatal stage in amniocytes and/or fetal blood lymphocytes. No one has been reported in chorionic villi probably because tetraploidy is generally considered in this tissue as a false positive result due to confined placental mosaicism (CPM) or placental culture artefacts. We report here on a case of tetraploidy detected in chorionic villi because of fetal cystic hygroma. We discuss the reliability of this diagnosis and propose guidelines in the follow-up of tetraploidies detected after chorionic villus sampling (CVS). Thus a misdiagnosis of this poor condition will be avoided at best and an appropriate genetic counseling will be given to the parents.     

葡萄胎中MBD2表达及其相关基因甲基化芯片研究

用Real-time RT-PCR、Western blot和免疫组织化学方法分别检测了去甲基化酶MBD2(methyl-CpG-binding domain 2,MBD2)在完全型葡萄胎(complete hydatidiform mole,CHM)和正常早期妊娠绒毛中的表达,用甲基化DNA免疫沉淀MeDIP(methylated DNA immunoprecipitation)-甲基化芯片分析完全型葡萄胎和正常早期妊娠绒毛中相关基因的甲基化情况,用生物信息学分析筛选了差异甲基化基因并进行功能分类。MBD2的mRNA在完全型葡萄胎中的表达明显高于正常早期妊娠绒毛(P=0.0083),Western blot(P=0.0005)和免疫组织化学(P=0.0091)检测到MBD2蛋白表达与Real-time RT-PCR结果一致。结果显示MBD2在完全型葡萄胎中的表达显著高于正常早期妊娠绒毛组织(P<0.01),与正常早期妊娠绒毛组织相比较,完全型葡萄胎组织中相对有89个基因发生了去甲基化,其中85个基因可被映射到基因组图谱中,MBD2在完全型葡萄胎中的高表达及部分基因的去甲基化可能在完全型葡萄胎的发生中扮演了重...     

Integrin-linked kinase (ILK) is highly expressed in first trimester human chorionic villi and regulates migration of a human cytotrophoblast-derived cell line

The placenta represents a critically important fetal-maternal interaction. Trophoblast migration and invasion into the uterine wall is a precisely controlled process and aberrations in these processes are implicated in diseases such as preeclampsia. Integrin-linked kinase (ILK) is a multifunctional, cytoplasmic, serine/threonine kinase that has been implicated in regulating processes such as cell proliferation, survival, migration, and invasion; yet the temporal and spatial pattern of expression of ILK in human chorionic villi and its role in early human placental development are completely unknown. We hypothesized that ILK would be expressed in trophoblast subtypes of human chorionic villi during early placental development and that it would regulate trophoblast migration. Immunoblot analysis revealed that ILK protein was highly detectable in placental tissue samples throughout gestation. In floating branches of chorionic villi, from 6 to 15 wk of gestation immunofluorescence analysis of ILK expression in placental tissue sections demonstrated that ILK was highly detectable in the cytoplasm and membranes of villous cytotrophoblast cells and in stromal mesenchyme, whereas it was barely detectable in the syncytiotrophoblast layer. In anchoring branches of villi, ILK was highly localized to plasma membranes of extravillous trophoblast cells. Transient expression of dominant negative E359K-ILK in the villous explant-derived trophoblast cell line HTR8-SVneo dramatically reduced migration into wounds compared to cells expressing wild-type ILK or empty vector. Therefore, our work has demonstrated that ILK is highly expressed in trophoblast subtypes of human chorionic villi during the first trimester of pregnancy and is a likely mediator of trophoblast migration during this period of development.     

Scanning electron-microscopic observations on the surfaces of chorionic villi of young and mature placentas

Mature placental material of full-term spontaneous births and 4-, 6-, 8- and 10-week-old placentas obtained from curettage cases were fixed in glutaraldehyde and osmium tetroxide for SEM examination. In young placentas, the ramifications of the chorionic villi start in the form of buds. The buds are transformed into tendrils with swollen extremities. These swellings resemble buds ready to bloom. The villi intertwine in different positions; both the villi and their tendrils are covered with dense layers of microvilli. In mature placentas, the surfaces of the chorionic villi and their ramifications are covered with microvilli. However, in comparison with the microvilli of young placentas, the microvilli here are less numerous and shorter. Invaginations were clearly visible on the surfaces of the villi; younger and newly budding microvilli, similar to those observed in young placentas, were seen in the invaginated regions. We had the impression that the mature placentas must regenerate in order to meet the increasing physiological requirements of the fetus.     

米非司酮对早孕绒毛Oct4、Sox2、Nanog 表达影响*

目的:探讨米非司酮对早孕绒毛组织Oct4、Sox2、Nanog mRNA和蛋白水平表达的影响。方法:要求终止妊娠的正常早孕妇女60例,分为:负压吸宫组及服用米非司酮150mg及米索前列醇联合行药物流产组。运用Real-time PCR方法检测两组早孕绒毛组织中Oct4、Sox2、Nanog mRNA的表达;采用免疫组织化学方法检测两组早孕绒毛组织Oct4、Sox2、Nanog蛋白的定位及半定量表达情况,比较两组差异。结果:Oct4、Nanog、Sox2 mRNA在药物流产组早孕绒毛中相对表达量明显低于负压吸宫组,差异有统计学意义(相对表达量分别为:0.15±0.045;0.37±0.053;0.23±0.040,P值均<0.05);Oct4、Nanog、Sox2在药物流产组早孕绒毛蛋白表达量亦明显低于负压吸宫组,差异有统计学意义(药物流产组蛋白表达量分别为13869±541、19251±1503、139492±918明显低于负压吸宫组22017±235、30543±729、37237±710)。结论:米非司酮可以通过抑制早孕绒毛中Oct4、Sox2、Nanog表达,发挥抗早孕作用。     

Zytogenetische Methoden in der Pr?nataldiagnostik

Cytogenetic analysis of amniotic fluid cells or chorionic villi are standard methods in invasive prenatal diagnosis. In certain cases, analyzing fetal blood cells or fetal cells of other origin represents an excellent supplementary investigation to disclose a fetal chromosomal aberration. At the microscopic level, chromosome analysis allows an examination of the complete genome. In the case of molecular analysis of monogenic disorders, native chorionic villi are the preferred tissue for targeted examination. Rapid advances in molecular non-invasive prenatal diagnosis will broaden parents?? options to exclude certain relevant genetic changes and will have an important impact on the field of invasive prenatal diagnosis.     

Immunophenotyping of mitotic cells from long-term cultures of chorionic villi

Chromosomal mosaicism in chorionic villus samples (CVS) may arise from different sources, such as clonal diversity within the chorionic tissue or contamination with maternal cells. To determine the origin of karyotyped cells, we compared the immunocytochemical features of mitotic cells in CVS long-term cultures with histological sections of their tissue of origin, i.e. chorionic villi. Immunolabelling of intermediate filaments specific for epithelial cells (cytokeratin) and mesenchymal cells (vimentin) established that mitoses yielded from CVS long-term cultures indeed stem from independently growing clones derived from both the epithelial and mesenchymal parts of the chorionic villi. Thus, mosaicism in CVS cultures may reflect true genetic heterogeneity within the biopsy. However, epithelial chorionic cells undergo in vitro metaplasia leading to co-expression of cytokeratins and vimentin. Fetal-specific immune markers (-HCG and SP1-glycoprotein) are not reliably expressed in CVS cell culture.     

Trisomy 16 confined to chorionic villi and unfavourable outcome of pregnancy.

Two cases of trisomy 16 confined to placental tissue associated with an unfavourable outcome of the pregnancy are reported. In the first case, after a diagnosis of an apparent non-mosaic trisomy 16 at chorionic villi sample (CVS), an intrauterine fetal death occurred at the 22nd week. In the second case a mosaic with trisomy 16 was found in chorionic villi and the fetus was still-born at 38 weeks. From a comparison of their cases with those of the literature, the authors conclude that a trisomy 16 confined to placental tissue has a negative effect on fetal growth and pregnancy outcome.     

Chromosome analysis in chorionic villi samples from the first trimester elective terminations

Chorionic villi sampling (CVS) has become a first trimester alternative to amniocentesis for prenatal diagnosis. The cytogenetic findings in 150 experimental samples are presented. The ages of the mothers ranged from 12 to 35 years, but the majority of them were 18 and 19 years of age. Various parameters of culturing and processing the samples in order to improve the method, were investigated. Short term incubation for 48 h was the method routinely employed in processing the biopsies for cytogenetic analysis. In the first series of 100 cases one mosaic case (46,XX/45,X), one Robertsonian translocation (13;14), one marker chromosome and one fragment were found. The foetal tissues were not analysed for chromosomes. In the second series of 50 samples, one case of mosaicism was found in the chorionic villi (46,XX/47,XX, 18q-), but this abnormality was absent in the foetal tissue. One variant inv(9) was observed in the foetal tissue as well as in the chorionic villi. In all other cases the karyotypes from the chorionic villi samples matched those of the corresponding foetal samples. There was no maternal contamination in this series of 50 samples. The discrepancies in the cytogenetic results from other investigators are discussed.