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PubMed2001

Decreased type III and V collagen expression in chorionic villi of hydatidiform mole.

To investigate the characteristic structure of hydatidiform mole, various types of collagen expression were determined in human villous tissues obtained from normal pregnancies (n = 17) and complete hydatidiform moles (n = 10). Indirect immunofluorescent staining was performed to detect type I, III, and VI collagen with specific monoclonal antibodies. Collagens were also extracted from the villous tissues obtained from normal pregnancy and hydatidiform mole by the salt precipitation method. Immunohistochemical staining for type I, III, and VI collagen revealed weak staining of the villous stroma in hydatidiform mole compared with that in normal pregnancy. Both the ratios of type III to type I collagen and the ratios of type V to type I collagen in the villous tissues were significantly decreased (P < 0.05) in molar pregnancy compared with those in normal pregnancy. These results suggest that alterations in the distribution and composition of collagen might play an important role in determining the pathophysiology and structure of hydatidiform mole.

Adult↗
PubMedDate not supplied

How can the frequency of false-negative findings in prenatal diagnoses of fra(X) be reduced: experience with first trimester chorionic villi sampling.

We report on 12 prenatal diagnoses performed between weeks 10 and 13 on normal women with a well-documented family history of the Martin-Bell syndrome. Seven were obligate and three were potential carriers. One male and 2 female fetuses were found to be fragile X [fra(X)]-positive. The diagnoses were confirmed in fibroblasts or lymphocytes after interruption or postnatally. In one fra(X)-negative female fetus, the analysis of linked DNA markers indicated that most probably she was a heterozygote. Reexamination after birth gave a fra(X)-positive result. Hence this was a case of a false-negative prenatal fra(X) result. The occurrence of false-negative cytogenetic results represents a common problem that limits the sensitivity of prenatal diagnostics in the Martin-Bell syndrome. A study of linked DNA markers can improve the reliability of negative cytogenetic results in first trimester prenatal diagnosis. In case of doubt, the chromosomes could be reexamined after fetal blood sampling.

Chorionic Villi Sampling↗
PubMed1993

[Early intra-amniotic bleeding and its results: dangers of chorionic villi sampling and early amniocentesis].

Four human fetuses are described exhibiting malformations related to EIAB. Two of these fetuses were aborted as a result of early prenatal diagnostic procedures: one after transcervical CVS, one after early amniocentesis. In three of these fetuses intraamniotic bleeding originating from the umbilical vein near the umbilical insertion produced cords of clotted blood and blood clots adhering to the surface of the fetus. Subsequently, the clots were organized by invading mesenchymal fibroblasts from fetal skin. The cords bent around extremities produced amputations (TLD) and constricted the umbilical vessels, if bent around the umbilical cord. The organizing surface blood clots located predominantly in the folds of the embryo, or fetus, influenced the growth of underlying tissues, producing oblique facial clefts, microphthalmia or micrognathia. EIAB represents a serious complication of invasive procedures related to prenatal diagnosis and must be regarded as the cause of malformations, such as TLD, or ADAM sequence. To avoid EIAB, CVS and amniocentesis should not be done before the end of the 11th gestational week.

Amniocentesis↗
PubMed2005

Mesenchymal progenitor cells derived from chorionic villi of human placenta for cartilage tissue engineering.

Human mesenchymal stem cells are currently being studied extensively because of their capability for self-renewal and differentiation to various connective tissues, which makes them attractive as cell sources for regenerative medicine. Herein we report the isolation of human placenta-derived mesenchymal cells (hPDMCs) that have the potential to differentiate into various lineages to explore the possibility of using these cells for regeneration of cartilage. We first evaluated the chondrogenesis of hPDMCs in vitro and then embedded the hPDMCs into an atelocollagen gel to make a cartilage-like tissue with chondrogenic induction media. For in vivo assay, preinduced hPDMCs embedded in collagen sponges were subcutaneously implanted into nude mice and also into nude rats with osteochondral defect. The results of these in vivo and in vitro studies suggested that hPDMCs can be one of the possible allogeneic cell sources for tissue engineering of cartilage.

Animals↗
PubMed1984

Ultrastructural observations of chorionic villi at term in diabetic women.

An electron microscopic study has been performed on placentas from women with maternal diabetes. None of the patients had suffered from any of the hypertensive complications of pregnancy (White's class A). Most villous trophoblasts were morphologically normal and showed features suggestive of normal or increased synthetic transport and excretory activity. These cells appeared to be far more "active" than their counterparts in normal term placentas in that many contained Golgi bodies that were often associated with membrane-bound osmiophilic vesicles. Focal thickening of the trophoblastic basement membrane was seen. The endothelial capillaries contained an excessive number of microfibrillae and micropinocytotic vesicles and appeared unduly immature. Very abundant osmiophilic granules were seen in many villous components, such as syncytiotrophoblasts, stromal fetal endothelial cells, pericytes, Hofbauer cells and fibroblasts. These may have been concerned in the cross-transportation of materials between the maternal intervillous space and the fetal capillaries, rather than the incorporation of substances within them. These morphological changes did not show, however, any specific, constant or uniform pattern of abnormality attributable maternal diabetes.

Basement Membrane↗
PubMed2000

Expression of the inducible nitric oxide synthase isoform in chorionic villi in the early spontaneous abortion.

To investigate the relationship between inducible nitric oxide synthase (iNOS) and the early spontaneous abortion., in situ hybridization and immunohistochemistry were used to detect the expression of iNOS in trophoblasts in the early pregnancy with and without spontaneous abortion (group I and group II). By light microscopy and computer color magic image analysis system (CMIAS), light density (D) and the positive cell number per statistic square (N/S) in situ hybridization were used to analyze the positive cell index, while total positive cells (N) and the positive unit (Pu) were used in immunohistochemistry. By in situ hybridization, D and N/S in trophoblasts were 0.35 +/- 0.028, 0.07 +/- 0.011 respectively in group I and 0.18 +/- 0.016, 0.015 +/- 0.003 in group II. In terms of immunohistochemical staining, N and Pu were 0.058 +/- 0.007, 11.94 +/- 2.01 in group I and 0.013 +/- 0.009, 1.08 +/- 0.35 in group II in trophoblasts. Significant differences existed between two groups. It is concluded that the higher nitric oxide produced by the higher expression of iNOS in trophoblasts might play an important role in the early spontaneous abortion.

Abortion, Spontaneous↗
PubMed2001

Overexpression of type IV collagen in chorionic villi in hydatidiform mole.

To investigate the characteristic structure of hydatidiform mole, type IV collagen expression was determined in human villous tissues obtained from normal pregnancies (n = 17) and complete hydatidiform moles (n = 10). Indirect immunofluorescent staining was performed to detect type IV collagen with specific monoclonal antibody, and Northern blot analysis was performed to assess expression of messenger ribonucleic acid for the alpha1(IV) chain. In addition, serum levels of type I, III, and IV collagen were measured by RIA. Immunohistochemical staining for type IV collagen revealed stronger staining of the trophoblastic basement membrane in hydatidiform mole than in normal pregnancy. Northern blot analysis revealed that the villous expression of messenger ribonucleic acid for the alpha1(IV) chain was significantly increased in hydatidiform moles compared with normal pregnancy (P < 0.01). Although there were no differences in the serum type I and III collagen levels between hydatidiform mole and normal pregnancy, the type IV collagen level was significantly higher in patients with hydatidiform mole than in normal pregnancy (P < 0.05). These results suggest that type IV collagen might play an important role in determining the pathophysiology and structure of hydatidiform mole.

Adult↗
PubMed1987

Chorionic villi sampling with an echogenic catheter: experiences of the first 500 cases.

Using a newly developed CVS catheter with enhanced echogenicity we performed CVS in 501 consecutive cases. The abortion rate of 4.3% prior to 28 weeks of gestation in this series is within the background rate of controls matched for maternal age. The loss rate was clearly correlated to the number of insertions, time of sampling and sampling success. CVS is safest between 9 and 11 weeks of pregnancy. We recommend to restrict the number of insertions to a maximum of 3. The rate of failed samplings was 4, reflecting a low "aggressiveness in seeking a sample". Complete follow-up of 259 consecutive cases gave no indication of an increased rate of congenital anomalies following CVS in early pregnancy. In our study we also performed cervical swabs, pregnancy hormone testing, maternal serum AFP determination prior to and after CVS as well as maternal AFP screening at 16 weeks of pregnancy together with a detailed sonographic examination. We conclude that CVS can be considered now a safe and reliable diagnostic procedure, but requires further detailed documentation and close follow-up in controlled trials.

Abortion, Spontaneous↗
PubMed1990

[Amniocentesis versus choriocentesis (chorionic villi sampling) and cordocentesis (fetal blood sampling)].

Opinions are still divergent regarding the respective place of amniocentesis and choriocentesis in the scheduled prenatal diagnosis. Amniocentesis (PLA) is the oldest method. This technique is perfectly mastered as well as its results, complications; its follow-up is 17-18 years in the world and over 16 years in Lyon. The rate of technical failures is inferior to 0.5 p. cent under ultrasonographic control. Its results are quite reliable (one error in 4 to 5,000 amniocentesis for the karyotype). The culture failures are under 1 p. cent. The titration of tracers, such as alpha-feto-protein or acetyl-cholinesterase is possible, favoring PLA over choriocentesis when there is a risk of neural dysraphias. PLA may be performed at any time during the pregnancy. Its main drawback seems to be its lateness: currently, the ideal time is 15-16 weeks. PLA performed earlier may result in more technical and culture failures. When performed at 12-13 weeks, it enters in competition with the choriocentesis although its theoretical risk of abortion is lower. Therefore, PLA and choriocentesis may be competitors, according to the risk factors and the indications, especially regarding cytogenetics.

Amniocentesis↗
PubMed1991

Uncommon chromosomal mosaicism in chorionic villi.

Three cases of unusual chromosomal mosaicism are reported for which the cytogenetic data show inconsistent findings between CVS and AC or fetal tissue, and which cannot be explained simply by non-disjunction. For case 1, in CVS the karyotype was 46,XY, whereas lymphocytes and fibroblasts revealed 69,XXY. DNA fingerprinting indicated one paternal and two maternal chromosome sets, the latter most probably due to omission of maternal meiosis II. For case 2, in CVS mos 46,XX/47,XX,+ mar de novo was observed. Amniotic fluid cells had the karyotype 46,XX. The origin of the marker chromosome might be explained by at least two events of unknown order (a somatic chromosome/chromatid deletion and non-disjunction of the homologous chromosome). In case 3 (CVS: mos 46,XY/46,XY,19q+ de novo; amniotic fluid cells, lymphocytes, and fibroblasts: 46,XY), the surplus of chromosome material in 19q+ might be explained on the basis of a somatic translocation. The idea of a chimera is less convincing, as the mosaic finding is restricted to one tissue. Furthermore, there was no hint of a vanishing twin. Hitherto, no case of structural chromosome mosaicism in CVS has been reconfirmed in fetal tissues.

Adult↗
PubMed1996

Isolation and characterization of human placental trophoblast subpopulations from first-trimester chorionic villi.

A method for the simultaneous preparation of highly enriched human placental trophoblast populations (villous and extravillous) from first-trimester placental villi (5 to 12 weeks) by using sequential trypsinization, percoll gradient centrifugation, and negative selection with anti-CD9 immunomagnetic separation is described. The purification method resulted in the isolation of four distinct trophoblast populations identified on the basis of morphology and phenotyping: (i) mononuclear villous cytotrophoblast cells which, through differentiation, become committed to syncytium formation; (ii) an extravillous trophoblast population which appeared as a "crazy pavement" and, with subsequent subculturing, differentiated morphologically to mononuclear cells; (iii) an extravillous trophoblast fraction which fused to form multinucleated trophoblast giant cells; and (iv) floating intermediate extravillous trophoblast cells which fused together to form cell clumps and which further differentiated to a mononuclear anchoring intermediate extravillous trophoblast. Short-term cultures of the freshly isolated cell fractions consisted of heterogeneous trophoblasts at different differentiation stages as determined by their varied biochemical and morphological properties. All the isolated trophoblast populations expressed the cytokeratin intermediate filament and the epithelium-specific cell-cell adhesion molecule E-cadherin. The isolated villous trophoblasts in culture expressed integrins alpha 6 and beta 4 and reduced levels of beta 1 subunits, whereas the proliferating extravillous trophoblast cultures expressed alpha 1, alpha 3, and alpha 5 and high levels of beta 1 integrin subunits, vitronectin receptor (alpha V beta 3/beta 5), and major histocompatibility complex class 1 molecules. Furthermore, the isolated trophoblast populations secreted metalloproteases (such as type IV collagenases [mainly 72- and 92-kDa enzymes, i.e., gelatinases A and B]) and urokinase plasminogen activator, as evaluated by substrate gel zymography. This method of isolation should facilitate in vitro studies of trophoblast proliferation, differentiation, invasion, virus interactions, cytokenesis, and immunology.

Cadherins↗
PubMed1995

Insulin and glucose modulate glucose transporter messenger ribonucleic acid expression and glucose uptake in trophoblasts isolated from first-trimester chorionic villi.

OBJECTIVE: Our purpose was to determine the effects of insulin and glucose on glucose transport and expression of GLUT1 glucose transporter messenger ribonucleic acid in first-trimester human trophoblast-like cells. STUDY DESIGN: First-trimester human trophoblast-like cells were maintained as a continuous cell line. For 2[3H]deoxy-D-glucose uptake and messenger ribonucleic acid studies the cells were incubated in the presence or absence of insulin (10(-7) to 10(-11) mol/L) or D-glucose (0 to 50 mmol/L) for 0 to 24 hours. Glucose transport was measured by incubating cells with 0.1 mmol/L 2[3H]deoxy-D-glucose for 5 minutes. Specific uptake was determined by incubating companion cultures with 10 mumol/L cytochalasin B. The cells were then solubilized with sodium hydroxide and the radioactivity counted. Data were expressed as nanomoles of 2[3H]deoxy-D-glucose transported per milligram of protein per 5 minutes and analyzed by one-way analysis of variance with post hoc testing by the method of Tukey. GLUT1 messenger ribonucleic acid was measured by Northern blotting of total ribonucleic acid samples hybridized to a phosphorus 32-labeled complementary deoxyribonucleic encoding the rat GLUT1 glucose transporter. As a control for loading efficiency, blots were stripped and rehybridized to a 40-mer phosphorus 32-labeled beta-actin oligonucleotide probe. RESULTS: Insulin treatment resulted in a dose-dependent increase in the transport of 2[3H]deoxy-D-glucose at 24 hours (p < 0.001 at 10(-7) mol/L). This change was first detected at 12 hours of incubation. These data closely paralleled the insulin-induced increase in GLUT1 messenger ribonucleic acid seen in Northern blots. In contrast to insulin, increasing concentrations of D-glucose did not change the transport of 2[3H]deoxy-D-glucose. However, when cells were incubated in low concentrations of D-glucose (0 or 1 mmol/L), an enhancement in the uptake of 2[3H]deoxy-D-glucose (p < 0.001) was observed. Kinetic studies indicated that D-glucose augmentation of 2[3H]eoxy-D-glucose uptake was significant at 9 hours (p < 0.05). The effects of D-glucose on GLUT1 messenger ribonucleic acid expression paralleled the uptake of 2[3H]deoxy-D-glucose, although the modulation of GLUT1 messenger ribonucleic acid levels by glucose was much less pronounced than in insulin-treated cells. CONCLUSION: Although it has been assumed that the placenta has a limited role in influencing glucose transport to the fetus, our in vitro data demonstrate that both insulin and glucose can modulate glucose transport at the cellular level of the placental trophoblast. Thus maternal insulin and glycemic status may influence the expression of GLUT1, the major trophoblast glucose transporter protein, therefore directly affecting first-trimester placental glucose transport. These in vitro data may help explain the association between maternal glucose abnormalities and impaired fetal development during the first trimester when placental GLUT1 messenger ribonucleic acid expression is at its peak.

Analysis of Variance↗
PubMed1979

Differentiated regions of human placental cell surface associated with attachment of chorionic villi, phagocytosis of maternal erythrocytes and syncytiotrophoblast repair.

Scanning electron micrographs of human placental cell surface show: (1) Differentiated zones of trophoblast which may be covered by fewer 'microvilli' than the adjacent syncytial cell surface and which extend as a narrow, usually distal protrusion of the chorionic villus. This narrow outgrowth terminates as a fractured end. Presumably since preparations were obtained from therapeutic terminations of pregnancy or Caesarian deliveries these broken ends represent the yield point in the anchoring 'villi' ruptured as a result of surgery. Similar anchoring 'villi' with fractured ends were observed in unfixed material with the use of Nomarski interference contrast microscopy. (2) It appears that, during apparent phagocytic uptake of maternal erythrocytes by syncytiotrophoblast, cell surface lining the forming vacuole still retains an irregular microvillous surface. This observation indicates the potential location of phagocytosis receptors for red blood cells in the placental cell surface. (3) Areas of human placenta which appears to have been damaged and may be undergoing repair exhibit masses of cells with conspicuous microvillar cell surfaces. The origin of these cells is discussed in relation to the usual processes of syncytiotrophoblast formation.

Cell Membrane↗
PubMed1977

Immunological studies of human placentae: identification and distribution of proteins in mature chorionic villi.

Cryostat sections of fifteen full-term, normal, human placentae have been studied by indirect immunofluorescence, using characterized antisera to a large number of proteins, in order to localize particular protein antigens to well-defined anatomical regions. Actin, plasminogen, and transferrin were identified in trophoblasts. Beta-2-microglobulin was uniformly absent from these cells. The complement component C3, the immunoglobulin IgG, and fibrinogen and collagen were identified in trophoblastic basement membranes. Of these IgG was the most sparingly represented, and C3 was not found on all trophoblastic basement membranes. Many proteins were identified within the stroma of chorionic billi, collagen being the most abundant. Many of these persisted following prolonged washing of the tissues. All four IgG subclasses were present in stroma, IgG1 and IgG3 being most prominent. Stromal cells were positive for beta-2-microglobulin, suggesting a unique sequestration of this protein on stromal cells but not on trophoblasts. Placental stem vessels were surrounded by collagen, and the walls of these vessels stained brightly for myosin: the vascular endothelium contained beta-2-microglobulin and actin. Peri- and inter-villous fibrin were faintly positive for several proteins, but these areas stained intensely for fibrinogen, plasminogen, alpha-2-macroglobulin and C4. This approach has proven to be useful in establishing precise definitions of the molecular morphology of normal human placentae.

Actins↗