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Report on first experiences in chorionic villi sampling in the first trimester of 131 pregnancies. Chorion biopsy was performed just before termination of pregnancy in the 9th-11th week of gestation. Of 3 tested biopsy methods we found the biopsy with a flexible forceps under guidance of real-time ultrasound to be the best.
Succinic semialdehyde dehydrogenase (SSAD) is an enzyme involved in the turnover of the neurotransmitter 4-aminobutyrate (GABA). Deficiency of SSAD results in developmental delay, ataxia, seizures and 4-hydroxybutyric aciduria. We have developed a simple fluorimetric assay for the enzyme and applied it to measurement of SSAD activity in a range of cell types often used for prenatal and postnatal diagnosis of enzyme defects. Lymphocytes from children with SSAD deficiency were found to have < 5% of the activity found in lymphocytes from normal children. Heterozygotes are asymptomatic and have intermediate enzyme activities. Although SSAD activity has been detected previously in uncultured chorionic villi, we found that SSAD was not expressed in cultured chorionic villus cells nor in some fibroblast-like amniocytes from control fetuses. Lymphocytes from fetal blood and non-fibroblastic amniocytes have high SSAD activities, and should be suitable for prenatal diagnosis of SSAD deficiency.
Insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) act as paracrine factors at or close to the sites of biosynthesis, i.e. cellular sites of expression of specific nRNAs. To determine the developmental pattern of expression of IGF-I, IGF-II, IGF-I R and IGFBP 1-6 mRNAs in the rhesus monkey placenta, in situ hybridization histochemistry was performed in placentae and fetal membranes from 65 days until term (165 +/- 5 days). IGF-I mRNA was not detectable in any of the specimens examined. IGF-II mRNA was localized abundantly in the placenta (syncytiotrophoblasts of the chorionic villi and the anchoring villi, and the extravillous cytotrophoblasts), and in the fetal membranes (chorion and amnion). IGF-I R mRNA was expressed predominantly in the decidua. All IGFBP mRNAs (IGFBP-1 to -6) were expressed in the maternal decidua in variable abundance. Only some IGFBP mRNAs, notably IGFBP-3 mRNA, was expressed in the fetal tissues, such as the chorionic mesoderm, some extravillous cytotrophoblasts and in the amnion and chorion. Gestational age did not alter the localization or relative abundance of all of the mRNAs studied. These findings suggest a role for IGF-II in the regulation of nutrient transport or placental hormone synthesis and/or secretion in the syncytiotrophoblasts, and a role for IGF-II and IGFBPs in the cell to cell communication and interaction at the feto-maternal interface.
Urgent diagnosis of uterine pregnancy of short duration by the method of "squashed preparations" is described. The unfixed pieces of tissue were stained with toluidine blue and squashed between two transparent plates. Subsequent microscopy could reveal the outlines of chorion villi.
Chorionic villi were sampled by transcervical aspiration after ultrasonic localization of the chorion frondosum. Sampling was successful in 82 of 98 women. Subsequent karyotyping of the chorionic material was done by the modified Evans method. Mitoses of reasonable quality were obtained providing an easy cytogenetic diagnosis from human cytotrophoblast. A second trimester chorionic plate biopsy and direct karyotyping in case of severe oligohydramnios and malformed fetus revealing numerical (45, XO) chromosomal abnormality is also reported.
Couples with alpha-thalassaemia-1 face a 25 per cent risk of having fetuses with haemoglobin (Hb) Bart's disease. Prenatal diagnosis is conventionally performed by DNA studies of chorionic villi or amniocytes obtained from chorionic villus biopsy or amniocentesis. DNA studies are expensive and time-consuming. We identified 11 affected pregnancies on abdominal ultrasound examination at 12-14 weeks when the placental thickness exceeded the mean plus 2 SD measurement for the gestational week and the cardiothoraic ratio was more than 0.5. Cordocentesis was then performed with a free hand technique. The procedures were successful in ten cases using a 26-gauge spinal needle with a 20-gauge introducer. Hb Bart's disease was confirmed in all cases by Hb electrophoresis. The procedure was unsuccessful in one case when a 22-gauge spinal needle was used. Hb study of fetal blood collected at abortion also confirmed Hb Bart's disease. In conclusion, ultrasound findings of concomitant placentomegaly and cardiomegaly at 12-14 weeks is highly specific of disease in pregnancies at risk of Hb Bart's disease. Cordocentesis and Hb study in pregnancies with these sonographic manifestations may be an alternative prenatal diagnostic approach. This diagnostic approach is of particular value in areas where resources for molecular studies are limited.
Restriction site polymorphisms are normal inherited variations in DNA that can be readily detected by restriction endonuclease analysis. Currently, 17 such polymorphisms are recognized within a 60 kb (kilobase) stretch of DNA which includes the beta-globin gene complex. Because of their proximity to the beta-globin gene, often these restriction site polymorphisms can be used to predict inheritance of beta-globin variants that produce disease. For example, restriction site polymorphisms can be used for prenatal diagnosis for the large majority of couples at risk of having a child with beta-thalassemia. When each member of such a couple is heterozygous at one or more of these 17 sites, family studies are usually successful in determining which forms of the polymorphism are co-inherited with the beta-thalassemia genes in that particular family. Subsequently, study of fetal DNA isolated from amniocytes obtained by midtrimester amniocentesis or from chorionic villi obtained by first trimester chorion biopsy will reveal which DNA polymorphisms that fetus has inherited. By deductive reasoning one can then predict which beta-globin genes it has co-inherited. Because of the general nature of these polymorphisms, which are related to the beta-globin gene and its variants only because of their proximity on chromosome 11, they are potentially useful in the prenatal diagnosis of any beta-chain hemoglobinopathy. Some hemoglobinopathies (including alpha-thalassemia, sickle cell anemia, and some cases of beta-thalassemia) can be detected directly by DNA analysis. In these cases in utero diagnosis does not need to rely on restriction site polymorphisms, which require preliminary family studies and are not applicable in all at risk pregnancies. Recently, genetic probes, which are necessary for detecting restriction site polymorphisms, have been isolated for sequences of several genes whose protein products are important in blood coagulation. These include probes for all three genes whose polypeptide products combine to form the fibrinogen molecule as well as probes for the prothrombin, Factor IX, Factor VIII, and antithrombin III genes. Defects in these genes are expected to be the causes of afibrinogenemia, prothrombin deficiency, hemophilia B, hemophilia A, and antithrombin III deficiency, respectively. From experience with other genes, it is expected that restriction site polymorphisms within and/or flanking these genes will be found.(ABSTRACT TRUNCATED AT 400 WORDS)
BACKGROUND: The human eosinophil granule major basic protein (MBP), a 13.8 kilodalton cationic polypeptide constituting the core of the eosinophil granule, is cytotoxic to parasites and numerous mammalian cells. Concentrations of a molecule immunochemically similar to eosinophil granule MBP are present in maternal plasma, and MBP mRNA has been localized to placental X cells by in situ hybridization. Eosinophil granule MBP is initially translated as a nontoxic precursor (proMBP), containing a 9.9 kilodalton acidic pro-portion that is believed to neutralize MBP toxicity. Recent analyses of sera from pregnant women have revealed that pregnancy-associated plasma protein-A (PAPP-A), previously thought to be a homotetramer of PAPP-A subunits, is actually composed of PAPP-A subunits bound by disulfide bonds to equimolar amounts of proMBP molecules to form a complex, PAPP-A/proMBP. In addition, the PAPP-A subunit nucleotide and deduced amino acid sequence have been determined from cloned cDNA. The PAPP-A monomer found in plasma contains 1547 amino acid residues. EXPERIMENTAL DESIGN: Because of the new evidence that PAPP-A is complexed with proMBP, previous studies on the localization of PAPP-A using antibodies to PAPP-A must be questioned. To determine the localization of the PAPP-A subunit, immunofluorescence was performed on normal placental tissues using proMBP absorbed anti-PAPP-A antibody. Furthermore, the expression of PAPP-A mRNA was investigated by in situ hybridization. RESULTS: Immunofluorescence staining with proMBP absorbed anti-PAPP-A antibody showed that PAPP-A is localized to placental septa, anchoring villi, and the syncytia of chorionic villi, whereas MBP is localized only to septa and anchoring villi. By in situ hybridization, PAPP-A mRNA is detected in placental X cells and syncytiotrophoblasts, but MBP mRNA is localized only to placental X cells. CONCLUSIONS: The presence of PAPP-A mRNA and PAPP-A subunit protein in placental X cells and syncytiotrophoblasts indicates that both X cells and syncytiotrophoblasts synthesize the PAPP-A subunit, whereas only X cells synthesize proMBP.
The distribution of the extra domain-containing form of cellular fibronectin was studied in human placentas at different stages of maturation by using the monoclonal antibody 52DH1 in indirect immunofluorescence. In early chorionic tissue (7 to 10 weeks post menstruationem) cellular fibronectin was codistributed with laminin and type IV collagen in the trophoblastic basement membranes. At weeks 11 to 12 the trophoblastic basement membranes were negative but positivity was typically revealed in distinct aggregates in the stromal tissue. In second-trimester and term placentas the immunoreactivity was confined to the vessel endothelia of villous stroma. Extravillous trophoblast cells seen in placentas at different stages did not show positivity. Double staining with the 52DH1 monoclonal antibody and polyclonal fibronectin antibodies showed that both in the early and term placentas there was much fibrillar positivity only revealed with the polyclonal antibodies. The present results show that cellular fibronectin is a prominent component of early trophoblastic basement membranes and may thus play a special role in the maturation of chorionic villi.
Kit ligand, or stem cell factor, is a recently identified growth factor, which binds to and activates the c-kit proto-oncogene, and which has been shown to act synergistically with other haematopoietic growth factors in the bone marrow. We have previously shown that several isoforms of kit ligand, which arise due to alternative splicing, are expressed in human placenta. In order to elucidate the role of c-kit and its ligand during human placental development we have investigated the expression of c-kit and kit ligand in human first trimester and term placenta as well as in pregnant and non-pregnant endometrium, by immunocytochemistry and flow cytometric analysis. In non-pregnant endometrium no expression of kit ligand was seen. By contrast, in first trimester decidua, kit ligand was strongly expressed by the arterial media of maternal blood vessels. Kit ligand was also expressed throughout pregnancy by invasive fetal extravillous trophoblast, and by fetal fibroblasts within the placental villi. c-kit was found to be expressed on Hofbauer cells within the chorionic villi, and by decidual macrophages at all stages in pregnancy. c-kit was also detected on the small CD56dim subset of uterine large granular lymphocytes which form the major leukocyte population in human first trimester decidua. Our results suggest that kit ligand may be involved in the regulation of fetal macrophages, and in particular in signalling between invading extravillous trophoblast which expresses kit ligand, and maternal leukocytes bearing the c-kit receptor.
Abnormal expression of class II MHC antigens was consistently observed in an immunohistological study on placentae from patients with pemphigoid gestationis. The area affected in all the placentae was the chorionic villi adjacent to the maternal decidua. The villous stroma, and in some cases the chorionic fetal endothelium, had abnormal expression of class II MHC antigens. Monoclonal antibodies specific for the class II MHC subregion products (DR, DP and DQ) were used to analyse the class II MHC antigen expression. Differential expression of the class II MHC subregion products was observed on the villous stroma and chorionic fetal endothelium; DR and DP were always expressed but DQ in some cases was heterogeneous. This abnormal expression of class II MHC antigens may reflect an immunological attack on the placenta in pemphigoid gestationis.
Morphological changes in fixed stromal cells and Hofbauer cells were studied throughout pregnancy in different types of placental chorionic villi by scanning electron microscopy. In the mesenchymal villus the fixed stromal cells were characterized by thin cytoplasmic processes. Hofbauer cells exhibited blebs on their surface. Large sail-like processes with a crescent profile which surrounded well developed stromal channels and a small cell body typified the small reticulum cells of the immature intermediate villus. The Hofbauer cells here displayed blebs, microplicae and large lamellipodia. Short cytoplasmic expansions and a large cell body characterized the fibroblasts present inside the stem villus. Hofbauer cells were rare, having blebs or a few short lamellipodia. The mature intermediate villus contained small and large reticulum cells. The latter had a much larger cell body than the small ones and displayed a few short cytoplasmic processes partly delimiting narrow incomplete stromal channels. Occasional Hofbauer cells with small microplicae and/or blebs were present. The small reticulum cells and fibroblasts present in the terminal villus showed similar morphological features as above. However, the former exhibited less developed cytoplasmic extensions and therefore no stromal channels were observed. In the terminal villus, the morphology of the rare Hofbauer cells was similar to that found in the mature intermediate villus.
BACKGROUND: The hematopoietic growth factor colony-stimulating factor-1 (CSF-1) and its receptor (encoded by the proto-oncogene c-fms) are implicated in the regulation of human placental development. EXPERIMENTAL DESIGN: In this study, we have performed a detailed immunohistochemical localization of the CSF-1 receptor (CSF-1R) on cells of the uteroplacental interface in human first trimester pregnancy, supplemented by Northern blot, in situ hybridization, and flow cytometric analysis. CSF-1R expression by JEG-3 and JAR choriocarcinoma cells was also investigated. RESULTS: c-fms mRNA was detected in primary cultures of first trimester trophoblast and was localized to the extravillous cytotrophoblast columns streaming off the anchoring villi. CSF-1R was expressed by fetal Hofbauer cells in the mesenchyme of the chorionic villi, and this expression increased considerably from first trimester to term. No expression was seen on first trimester and term villous cytotrophoblast. CSF-1R expression on villous syncytiotrophoblast was absent at 6 weeks, strongest at 8-10 weeks, and faded by 12 weeks. First trimester extravillous cytotrophoblast columns were strongly and consistently positive for CSF-1R expression, as was the superficial shell of extravillous trophoblast over the maternal decidua. However, with deeper invasion and terminal differentiation into placental bed giant cells, this expression became weak or absent. Endovascular trophoblast was also only weakly positive for CSF-1R. At the implantation site itself, large numbers of decidual macrophages and CD3-, CD56bright large granular lymphocytes were seen. The macrophages expressed CSF-1R strongly, but large granular lymphocytes, decidual stromal cells, glandular epithelium, and endothelial cells were found to be negative for CSF-1R expression. No CSF-1R expression was detected in JAR choriocarcinoma cells, but CSF-1R was present in first trimester cultured trophoblast and JEG-3 choriocarcinoma cells, although this was shown to be intracellular. CONCLUSIONS: These results suggest that CSF-1 may regulate invasion and differentiation of human placental trophoblast, depending upon the spatial and temporal distribution of its receptor. CSF-1 may also influence placental development and function by acting via decidual and fetal macrophages, which are the other cell populations expressing the receptor.
The distribution of fibronectin in tissues of four human foetuses (7-14 gestation weeks/GW) and twenty seven pig foetuses (25-114 days of gestation) was investigated using immunofluorescence and avidin/biotin methods. Fibronectin was abundant in the circulatory and gastrointestinal system and its derivates, in reticular stroma of immune organs, and in connective tissues and chorionic villi at all developmental stages.
Transport of iron from the mother to the fetus is essential for the normal development of the fetus and abnormalities in the transferrin receptor (TFR) on the placental trophoblasts might have some crucial effects on the fetal iron metabolism. The present study was undertaken to determine whether there are any changes in the expression of the transferrin receptor in the placenta from pre-eclamptic mothers. An immunohistochemical study using antibodies specific for C-terminus and N-terminus regions of the TFR revealed that TFR expression by syncytiotrophoblasts around chorionic villi is markedly reduced in placentae from pre-eclamptic pregnancies compared to those from normal pregnancies and pregnancies at early gestational age that terminated by abortion. The same result, although to a lesser extent, was obtained even in trophoblasts which were located around atrophic villi with fibrotic changes in the interstitium, or which invaded into the deciduas. The expression of human chorionic gonadotropin (HCG) on those cells was observed to the same extent in the normal and pre-eclamptic pregnancy groups. The concentration of TFR in the peripheral blood also decreased in pre-eclampsia. These results suggest that TFR synthesis in the pre-eclampsia, especially in the placental trophoblasts, is decreased.
OBJECTIVE: To assess whether fluorescence in situ hybridization (FISH) with chromosome 21, specific DNA probe is applicable as a prenatal diagnostic tool for Down's syndrome. METHOD: We used FISH with chromosome 21 specific probe on 30 uncultured chorionic villi cell samples to detect the Down's fetus, and we also performed the conventional chromosome analysis of chorion cells from parallel samples. RESULTS: In samples with disomic karyotype, an average of 1 percent (0-5 percent) of the nuclei had three hybridization signals. By contrast, in the samples of trisomy 21 fetus, an average of 86 percent (78-91 percent) of the nuclei displayed three signals. CONCLUSION: FISH can provide a rapid and accurate method for the first trimester prenatal diagnosis of Down's syndrome.
The scanning ultrastructural examination of a series of 31 hydatidiform mole and 12 healthy placental specimens of similar gestational age has revealed a variety of surface architectures more common in molar tissue. Characteristic paddle-shaped sprouts, ridging of the syncytial maternal oriented surface and microgibbosities are described. These structures are explicable in terms of organellar hyperplasia of cortical cytoskeletal elements found in healthy tissue. Specific morphological evidence of involvement of these elements in a condition where aberrant growth control leads to the characteristic trophoblastic hyperplasia is a further indication that cytoskeletal elements may mediate transformation. An increase in resolution obtained over previous scanning electron microscope studies has allowed the description of detailed features such as 'caveolar collars' on the maternal oriented healthy and molar trophoblast surfaces. These observations are of relevance to understanding the mechanisms of several cell physiological processes, including transepithelial transport. New observations of a reticular organization in the surface layer of molar trophoblast indicate that a syncytioskeletal layer, with organization resembling that previously described in healthy chorionic villi, is also present in molar villi.
We used fourteen sets of primers to detect the gene deletion of 27 clinically diagnosed DMD patients by multiplex PCR technic. The detection rate was 59%. We found that the deletion region was more concentrated in the region of exon 43 to 52. The data was discussed. Twenty-two mothers of the twenty-seven affected children were pregnant again, and prenatal diagnosis was done by multiplex PCR of the DNA of the chorionic villi. Four affected fetuses were found and aborted.