Showing papers in "Molecular Human Reproduction in 2004"

Anti‐Müllerian hormone expression pattern in the human ovary: potential implications for initial and cyclic follicle recruitment

Abstract: Anti-Mullerian hormone (AMH) is a member of the transforming growth factor-b superfamily, which plays an important role in both ovarian primordial follicle recruitment and dominant follicle selection in mice. However, the role of AMH in folliculo- genesis in humans has not been investigated in detail. In the present study, AMH expression was assessed using immunohisto- chemistry in ovarian sections, obtained from healthy regularly cycling women. To this end, a novel monoclonal antibody to human AMH was developed. AMH expression was not observed in primordial follicles, whereas 74% of the primary follicles showed at least a weak signal in the granulosa cells. The highest level of AMH expression was present in the granulosa cells of secondary, preantral and small antral follicles <4 mm in diameter. In larger (4-8 mm) antral follicles, AMH expression grad- ually disappeared. In conclusion, in the human AMH expression follows a similar pattern as compared to the mouse and rat, suggesting an important role of AMH in folliculogenesis.

Decidual and peripheral blood CD4+CD25+ regulatory T cells in early pregnancy subjects and spontaneous abortion cases.

Abstract: Human pregnancy represents a situation of semiallograft to maternal host. Therefore, it has been reported that tolerance to the fetal allograft represents a mechanism for maintaining a pregnancy. CD4 + CD25 bright regulatory T cells are known to play an important role in the development and maintenance of tolerance in peripheral tissues. However, the potential role of CD4 + CD25 bright T cells in maintaining human pregnancy has not been reported. In this study, we show that early human pregnancy decidua contains an abundance of CD4 + CD25 bright T cells, which express CD152(CTLA-4) at a high level. CD4 + CD25 bright T cells mediate potent inhibition of autologous T-cell proliferation by anti-CD3 stimulation. Furthermore, these cells inhibit the proliferation of autologous CD4 + CD25 - T cells in a dose-dependent fashion. This suppressive function of decidual CD4 + CD25 + T cells required cell-to-cell contact. The proportion of decidual CD4 + CD25 bright T cells was significantly lower in specimens from spontaneous abortion compared to those from specimens from induced abortions. These results suggest that decidual CD4 + CD25 bright T cells contribute to the mechanisms mediating maternal immune tolerance of conceptus antigens and therefore might contribute to the maintenance of pregnancy.

Effect of controlled ovarian hyperstimulation in IVF on endometrial gene expression profiles.

Abstract: Controlled ovarian hyperstimulation (COH) used in IVF produces lower implantation rates per embryo transferred compared to natural cycles utilized in ovum donation, suggesting a suboptimal endometrial development. Endometrial receptivity has recently been investigated in natural menstrual cycles with the aid of microarray technology. The aim of this study is to investigate the impact of COH using urinary gonadotrophins with a long protocol with GnRH agonists without progesterone supplementation (similar to the natural cycle) on endometrial gene expression profiles during the window of implantation by comparing the profiles at day hCG + 7 of COH versus LH + 7 of a previous natural cycle in the same women. For this purpose we have used microarray technology by Affymetrix (GeneChip HG_U133A), which allows more than 22,000 genes to be tested simultaneously. Results were validated by semi-quantitative PCR and quantitative PCR experiments. We found that more than 200 genes showed a differential expression of more than 3-fold when COH and normal cycles were compared at hCG + 7 versus LH + 7. We simultaneously re-analysed the LH + 2 versus LH + 7 endometrial gene expression profiles in previous natural cycles in the same subject using this specific GeneChip, the results obtained were consistent with our own published results. This is the first time that gene expression profiles of the endometrium during COH are reported. The large degree of gene expression disturbance is surprising and highlights the need for further efforts to optimize COH protocols.

First trimester trophoblast cells secrete Fas ligand which induces immune cell apoptosis

Abstract: Since the invading trophoblast represents a semi-allograft, it should be rejected by the mother. It has, therefore, been postulated that during normal pregnancy the trophoblast evades the maternal immune system though the establishment of immune privilege by triggering the death of activated lymphocytes which may be sensitized to paternal alloantigens. Such peripheral tolerance may be directed through the Fas/Fas ligand (FasL) apoptotic pathway and mediated by FasL expressed by the trophoblast. However, in vivo studies show that membrane-associated expression of FasL may instead promote allograft rejection, rather than protection. The aim of this study was to determine if there is a role for FasL in trophoblast immune privilege. In this study, we demonstrate that isolated first trimester trophoblast cells lack membrane-associated FasL, but express a cytoplasmic form in association with a specialized secretory lysosomal pathway. Furthermore, this intracellular FasL is constitutively secreted by trophoblast cells via the release of microvesicles. Following disruption of these microvesicles, the whole 37 kDa secreted FasL is able to induce T-cell death by apoptosis through activation of the Fas pathway. Therefore, we propose that secretion of FasL may be one mechanism by which trophoblast cells promote a state of immune privilege and, therefore, protect themselves from maternal immune recognition.

Isothermal whole genome amplification from single and small numbers of cells: a new era for preimplantation genetic diagnosis of inherited disease

Abstract: Preimplantation genetic diagnosis (PGD) of single gene defects following assisted conception typically involves removal of single cells from preimplantation embryos and analysis using highly sensitive PCR amplification methods taking stringent precautions to prevent contamination from foreign or previously amplified DNA. Recently, whole genome amplification has been achieved from small quantities of genomic DNA by isothermal amplification with bacteriophage 29 DNA polymerase- and exonuclease-resistant random hexamer primers. Here we report that isothermal whole genome amplification from single and small numbers of lymphocytes and blastomeres isolated from cleavage stage embryos yielded microgram quantities of amplified DNA, and allowed analysis of 20 different loci, including the DeltaF508 deletion causing cystic fibrosis and polymorphic repeat sequences used in DNA fingerprinting. As with analysis by PCR-based methods, some preferential amplification or allele drop-out at heterozygous loci was detected with single cells. With 2-5 cells, amplification was more consistent and with 10 or 20 cells results were indistinguishable from genomic DNA. The use of isothermal whole genome amplification as a universal first step marks a new era for PGD since, unlike previous PCR-based methods, sufficient DNA is amplified for diagnosis of any known single gene defect by standard methods and conditions.

Analysis and significance of mRNA in human ejaculated sperm from normozoospermic donors: relationship to sperm motility and capacitation

Abstract: The existence of a complex population of mRNA in human sperm is well documented but their role is not yet elucidated. Using discontinuous density gradients, we have isolated high and low motile sperm from the same semen sample. The levels of different transcripts coding for molecules either involved in nuclear condensation (protamines 1 and 2) or in capacitation [endothelial nitric oxide synthase (eNOS), neuronal nitric oxide synthase (nNOS) and c-myc] were then assessed in the two populations using semi-quantitative RT-PCR. Sperm viability was estimated by eosin-nigrosin staining and by hypo-osmotic swelling test; apoptosis percentage was measured by the TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling technique. The contamination by somatic and germ cells was assessed by looking for specific molecular markers of these cells, respectively CD-45 and E-cadherin for somatic cells and c-kit for germ cells. The viability of sperm was unchanged in high and low motile fractions, as well as DNA fragmentation percentage. The amount of Prm-1 mRNA was significantly higher in low density motile than in the high motile fraction. In most of high motile sperm samples eNOS and nNOS transcripts were undetectable whereas they were present in the low motile sperm. In contrast, no significant variation was found in the c-myc/Prm-2 mRNA ratio between the two populations. Moreover, a partial or complete disappearance of c-myc transcripts was observed after capacitation. Thus analysing mRNA profiles could be helpful as a diagnostic tool and prognosis value for fertilization.

Alterations in mitochondrial membrane potential during preimplantation stages of mouse and human embryo development.

Abstract: Mitochondria are cellular organelles regulating metabolism and cell death pathways. This study examined changes in mitochondrial membrane potential (deltapsim) throughout the stages of preimplantation development in mouse embryos conceived either in vivo or in vitro and human embryos donated to research from IVF. Embryos stained with the deltapsim-sensitive dye (JC-1) were quantified for the ratio of high- to low-polarized mitochondria using a deconvolution microscope. Overall, mouse zygotes and early embryos contain a subset of high-polarized mitochondria with a progressive increase in the ratio of deltapsim observed with increasing cleavage. A transient increase in the ratio of high to low deltapsim was observed in in vivo fertilized 2-cell stage embryos, coincident with embryonic genome activation in the mouse, but not in 2-cell embryos obtained through IVF. We further observed that arrested mouse 2-cell embryos possessed an increased ratio of deltapsim compared with non-arrested embryos. In human 8-cell embryos we observed an increased ratio of high- to low-polarized mitochondria with increasing degrees of embryo fragmentation. We concluded that the pattern of mitochondrial membrane potential progressively changes throughout preimplantation development, and that an aberrant shift in deltapsim could contribute to, or is associated with, decreased developmental potential.

Turning it on and off: M-phase promoting factor during meiotic maturation and fertilization.

Abstract: Maturation (M-phase) promoting factor (MPF) plays a pivotal role in oocytes during their maturation. This review concentrates on its function at three important time-points. First, its activation during meiotic progression from prophase I arrest at germinal vesicle breakdown. Second, its role during the transition from meiosis I to meiosis II, a defining feature of meiosis involving segregation of homologous chromosomes. Third, maintenance of its activity at metaphase II arrest and the necessity for its destruction during oocyte activation. An understanding of how oocytes switch it on and turn it off underpins much of the basic cell biology of oocyte maturation.

Cellular maturity and apoptosis in human sperm: creatine kinase, caspase-3 and Bcl-XL levels in mature and diminished maturity sperm.

Abstract: The relationship between human sperm maturity and apoptosis is of interest because of the persistence of immature sperm in ejaculates in spite of various apoptotic processes during spermatogenesis. We assessed sperm maturity by HspA2 chaperone levels, and plasma membrane maturity by sperm binding to immobilized hyaluronic acid (HA). We also utilized objective morphometry. Sperm were stained with three antibody combinations: active caspase-3/creatine kinase (CK, a marker of cytoplasmic retention), caspase-3/the antiapoptotic Bcl-(XL), and CK/Bcl-(XL). In semen, 13% of sperm stained with CK, caspase-3 or Bcl-(XL), and 28% had stained with two markers. In the mature HA-bound sperm fraction, 80% of sperm) in the midpiece. Morphometrical attributes of clear, single- and double-stained sperm, in line with their more pronounced maturation arrest, showed an incremental increase in head size (due to cytoplasmic retention) and shorter tail length. We hypothesize that during faulty sperm development, three alternatives may occur: (i) elimination of aberrant germ cells by apoptosis; (ii) in surviving immature cells, caspase-3 is activated, and in response the antiapoptotic Bcl-(XL), and perhaps HspA2, provide protection; (iii) in a third type of immature sperm, in addition to the CK, caspase-3 and Bcl-(XL) expression, there are related manifestations of increased head size and shorter tail length. Thus, immature sperm may vary in the type of developmental arrest and in protection mechanisms for apoptosis. These variations are likely to explain the persistence of immature sperm in the ejaculate.

Molecular classification of human endometrial cycle stages by transcriptional profiling.

Abstract: Endometrium is a dynamic tissue that undergoes cyclic changes each month, under the overall control of estrogen and progesterone. The aims of this study were to investigate the changing global gene expression profile of human endometrium during the menstrual cycle using microarray technology and to determine the correlation between histopathological evaluation and molecular profile of the samples. Standard two-colour cDNA microarrays were performed on the 43 samples against a common reference, using a 10.5 K cDNA glass slide microarray. The results were validated using real-time PCR. Analysis of expression data was carried out using parametric analysis of variance with Benjamini-Hochberg correction. Hierarchical clustering reveals a strong relationship between histopathology and transcriptional profile of the samples. The study identified 1452 genes that showed significant changes in expression (P< or =0.05) across the menstrual cycle, with 425 genes having changes that are at least 2-fold. The data were also independently analysed by a CSIRO algorithm called GeneRaVE that identified a small subset of genes whose expression profiles could be used to classify nearly all the biopsies into their correct cycle stage. We also identified and validated three genes [(natural cytotoxicity triggering receptor (NCR)3, fucosyl transferase (FUT)4 and Fyn-binding protein (FYB)] that had not been shown to have significant cyclic changes in the human endometrium, previously. We have shown for the first time that endometrial cycle stage prediction is possible based on global gene expression profile.

Oct-4 mRNA and protein expression during human preimplantation development.

Abstract: The transcription factor OCT-4 is regarded as a critical factor in controlling mammalian early embryonic development because of its role in toti-/pluripotency. In human preimplantation embryos, OCT-4 studies are limited to RNA analysis of abnormally developing embryos. This study thoroughly investigated the expression pattern of OCT-4 throughout the human preimplantation development. Expression was examined by single-cell RT-PCR or indirect immunocytochemistry in 36 single oocytes of various maturity and 112 normally developing preimplantation embryos at the level of single blastomeres, morulas, blastocysts, or inner cell mass (ICM) and trophectoderm (TE) samples. Oocytes and cleavage stage embryos revealed a variable OCT-4 expression pattern, concomitant with a pure cytoplasmic localization of the protein. During compaction, the variability in expression faded away indicating embryonic OCT-4 expression and the protein appeared in the nucleus implying biological activity. In blastocysts, OCT-4 transcripts and proteins were present in the ICM and the TE. At protein level, blastocysts displayed different spatial expression patterns within a cell for the splice variants of OCT-4, which may endow them with different functional properties. As OCT-4 transcripts were also found in various differentiated cells, the presence of OCT-4 transcripts or proteins may not be sufficient for identifying undifferentiated cell lines in humans. Further, we suggest to examine the localization of OCT-4 proteins within a cell rather than to look for the presence and/or amount of transcripts.

Association between HLA‐G genotype and risk of pre‐eclampsia: a case–control study using family triads

Abstract: Pre-eclampsia affects 2‐7% of all pregnancies with varying severity and is a leading cause of maternal and fetal mortality and morbidity. The aetihology involves almost certainly a combination of genetic predisposition with maternal and fetal contributions and environmental factors. Research points towards pathologies in the placenta as the triggering factor which leads to systemic endothelial dysfunction in the mother, probably as the result of interaction with released placental factors circulating in the maternal blood. One prominent hypothesis regarding the aetiology of pre-eclampsia suggests that it is caused by immunemaladaptation. The MHC class Ib gene, HLA-G, is expressed in the placenta and seems to have immunomodulatory functions. Aberrant HLA-G mRNA and protein expression in pre-eclamptic placentas have been reported. Here, we have investigated detailed HLA-G genotypes in a case‐control study of 155 family triads of mother, father and newborn. Among primiparas, an overrepresentation of a homozygous HLA-G genotype was detected in the 40 pre-eclamptic offspring compared to the 70 controls [P = 0.002, Fisher’s exact test; odds ratio 5.57 (95% CI 1.79‐17.31)]. Further analyses suggested that the differences between pre-eclamptic cases and controls primarily were accomplished by a different transmission from the father of a 14 bp deletion/insertion polymorphism in exon 8 (P = 0.006, Fisher’s exact test), which previously has been linked to differences in the levels of HLA-G expression and in HLA-G mRNA splicing. The results may also indicate that combined mother‐child HLA-G genotypes could influence the risk of developing pre-eclampsia. Overall, the study suggests that HLA-G genotypes and expression might have a significant influence on development of pre-eclampsia.

Galectin fingerprinting in human endometrium and decidua during the menstrual cycle and in early gestation.

Abstract: The emerging functionality of the sugar code via cell surface glycans and endogenous lectins ascribes pertinent roles in cell physiology to the carbohydrate signals of cellular glycoconjugates. To initiate monitoring of endogenous lectins in human endometrium, we focused on a family of growth/adhesion-regulatory lectins, i.e. galectins. Comprehensive fingerprinting was performed on samples throughout the menstrual cycle and in decidua. The endometrium (n = 30) and decidua (n = 7) were collected from patients undergoing hysterectomy for benign reasons and from induced abortions. Measurements by RT-PCR and then by multiprobe RNase protection assay with total endometrial and decidual tissue and with epithelial cells, stromal cells and CD45-positive cell fractions (n = 16), isolated by the use of antibody-coated magnetic beads, revealed a predominant expression of galectins-1 and -3. Protein analysis was performed by immunocytochemistry with monoclonal and polyclonal antibodies (n = 40). Galectin-1 was localized mainly in stromal cells, whereas galectin-3 was predominantly found in epithelial cells. Expression of galectin-1 increased significantly in the late secretory phase endometrium and in the decidual tissue. Expression of galectin-3 increased significantly during the secretory phase of the menstrual cycle. Cycle-dependent expression of galectin-1 in stromal cells and galectin-3 in epithelial cells suggest these lectins to be involved in the regulation of different endometrial cellular functions.

Multiple displacement amplification on single cell and possible PGD applications

Abstract: Multiple displacement amplification (MDA) is a technique used in the amplification of very low amounts of DNA and reported to yield large quantities of high-quality DNA. We used MDA to amplify the whole genome directly from a single cell. The most common techniques used in PGD are PCR and fluorescent in-situ hybridization (FISH). There are many limitations to these techniques including, the number of chromosomes diagnosed for FISH or the quality of DNA issued from a single cell PCR. This report shows, for the first time, use of MDA for single cell whole genome amplification. A total of 16 short tandem repeats (STRs) were amplified successfully with a similar pattern to the genomic DNA. Furthermore, allelic drop out (ADO) derived from MDA was assessed in 40 single cells by analysing (i) heterozygosity for a known beta globin mutation (IVSI-5 C-G) and by studying (ii) the heterozygous loci present in the STRs. ADO turned out to be 10.25% for the beta globin gene sequencing and 5% for the fluorescent PCR analysis of STRs. Moreover, the amplification accuracy of MDA permitted the detection of trisomy 21 on a single cell using comparative genome hybridization-array. Altogether, these data suggest that MDA can be used for single cell molecular karyotyping and the diagnosis of any single gene disorder in PGD.

Comparative genomic hybridization and karyotyping of human embryonic stem cells reveals the occurrence of an isodicentric X chromosome after long-term cultivation.

Abstract: Human embryonic stem (hES) cells are important research tools in studies of the physiology of early tissue differentiation. In addition, prospects are high regarding the use of these cells for successful cell transplantation. However, one concern has been that cultivation of these cells over many passages might induce chromosomal changes. It is thus important to investigate these cell lines, and check that a normal chromosomal content is retained even during long-term in vitro culture. Comparative genomic hybridization (CGH) was used to analyse three hES cell lines derived in our laboratory and cultured continuously for 30-42 weeks, comprising 35-39 cell passages. CGH could be successfully performed in 48 out of a total of 50 isolated single cells (96%). All three lines (HS181, HS235 and HS237) were shown to have a normal chromosomal content when analysed by both single cell CGH and by karyotyping up to passages 39, 39 and 35 respectively. No aneuploidies or larger deletions or amplifications were detected, and they were female (46,XX). However, HS237 was reanalysed at passage 61, and at that point an aberrant X chromosome was detected by karyotyping. The aberration was confirmed and characterized by single cell CGH and fluorescence in situ hybridization analysis, 46,X,idic(X)(q21). Thus, chromosomal aberrations may occur over time in stem cell lines, and continuous analysis of these cells during cultivation is crucial. Single cell CGH is a method that can be used for continuous analysis of the hES cell lines during cultivation, in order to detect chromosome imbalance.

Expression analysis of the human testis‐specific serine/threonine kinase (TSSK) homologues. A TSSK member is present in the equatorial segment of human sperm

Abstract: Two members of the human testis-specific serine/threonine (Ser/Thr) kinase family, TSSK 1 and TSSK 2, were cloned and sequenced from a human testis adaptor-ligated cDNA library using a PCR strategy. Within the cDNA, open reading frames (ORF) were defined encoding proteins of 367 and 358 amino acids respectively, as well as conserved kinase domains typical of the superfamily of Ser/Thr kinases. Both genes were intronless and mapped to chromosomes 5 and 22 respectively. The human and mouse homologues of TSSK 1 and TSSK 2, together with TSSK 3 and SSTK/FKSG82, constitute a kinase subfamily closely related to the calmodulin kinases and SNF/nim 1 kinase subfamilies. Similar to the mouse, tissue expression by northern and dot blot analysis revealed that human TSSK 1 and 2 messages are expressed exclusively in the testis. However, mRNA for these kinases can be detected in other tissues using real-time PCR. In addition, TSKS, the human homologue of a putative substrate of TSSK 1 and 2, was cloned. TSKS had an ORF of 592 amino acids and was also expressed exclusively in the testis as demonstrated by northern and dot blot analyses; however, lower levels of expression in other tissues were detected using real-time PCR. Human TSSK 2 and TSKS interacted in a yeast two-hybrid system and also co-immunoprecipitated after in vitro translation. TSSK 2 expressed in yeast and bacteria was able to autophosphorylate and also phosphorylated recombinant TSKS in vitro. Antibodies against recombinant TSSK 2 demonstrated that a member of the TSSK family was present in human testis and localized to the equatorial segment of ejaculated human sperm. In contrast, TSKS was only found in the testis. The finding of a TSSK family member in mature sperm suggests that this family of kinases might play a role in sperm function.

Both mitogen-activated protein kinase and phosphatidylinositol 3-kinase signalling are required in epidermal growth factor-induced human trophoblast migration

Abstract: Adequate extravillous trophoblast (EVT) invasion is an essential step for placental formation. The aim of this study was to examine the possible role of phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) signalling in epidermal growth factor (EGF)-induced EVT migration and to determine if the 70 kDa ribosomal S6 kinase (p70S6K) is involved in this process. In this study, EGF significantly stimulated HTR8/SVneo cell migration and the phosphorylation of AKT, ERK1/2 and p70S6K in a concentration-dependent manner. The MAPK inhibitor U0126 decreased cell migration and ERK phosphorylation, but it did not influence p70S6K phosphorylation in response to EGF. In the presence of PI3K inhibitors (Wortmannin), EGF-stimulated trophoblast migration and phosphorylation of AKT and P70S6K (Thr(389) and Thr(421)/Ser(424)) were decreased, while EGF-induced ERK phosphorylation was not affected. Expression of an activated AKT (Myr-AKT2) increased basal phospho-p70S6K (Thr(389) and Thr(421)/Ser(424)) content, but failed to stimulate cell migration. However, it induced cell migration in the presence of EGF and Wortmannin, in which both AKT and MAPK pathways were activated. In addition, there was a concentration-dependent inhibition of cell migration and p70S6K phosphorylation (Thr(389) and Thr(421)/Ser(424)) in the presence of Rapamycin, a specific inhibitor of the mammalian target of rapamycin (mTOR, a downstream of AKT). Taken together, our data suggest that EGF-induced trophoblast migration involves the coordinated regulation of both PI3K/AKT and MAPK signalling pathways. mTOR/p70S6K is important in PI3K- but not MAPK-mediated trophoblast migration in response to EGF.

Somatic cell apoptosis markers and pathways in human ejaculated sperm: potential utility as indicators of sperm quality

Abstract: In this study we extended earlier work to determine whether sperm respond to somatic cell apoptotic stimuli and whether apoptotic phenotypes are significant indicators of human sperm quality. We evaluated ejaculated sperm from fertile donors and subfertile patients following purification of fractions of high and low motility. In unstimulated conditions, caspase enzymatic activity was higher in motile fractions from subfertile patients than in donors, and was higher in low motility fractions from both groups. Staurosporine, but not a Fas ligand or H2O2, significantly increased caspase activity, but only in high motility fractions. Procaspase-3, -7 and -9 and low levels of active caspase-3, -7 and -9 were identified by immunoblot analysis. Apoptosis-inducing factor (AIF) was present in all samples but poly ADP-ribose polymerase-1 (PARP-1) was not detected. Phosphatidylserine translocation was significantly increased only with H2O2 treatment. In ejaculates of both subfertile and fertile men, we demonstrated the presence and activation of several proteins that are key constituents of apoptosis-related pathways in somatic cells, which may serve as markers for sperm quality.

Aneuploidy detection in single cells using DNA array‐based comparative genomic hybridization

Abstract: The use of metaphase comparative genomic hybridization (CGH) to screen all human chromosomes for aneuploidy in preim-plantation embryos is hindered by the time required to perform the analysis. We report in this paper a novel approach to manufacture a DNA microarray for CGH for the detection of aneuploidy in single cells. We spotted human chromosome-specific libraries on glass slides that were depleted of repetitive sequences and tested our array CGH method in 14 experiments using either single male and/or single female lymphocytes. For the autosomes, the mean normalized ratios were all close to the expected ratio of 1.0 with overall 300/308 (97%) of the normalized ratios falling within the range 0.75 to 1.25. It was possible to deduce the correct copy number of the X chromosome in 13/14 (92.9%) separate array CGH experiments but the Y chromosome in only 4/14 (29%). We tested our microarray CGH method on a single fibroblast from each of three cell lines containing a specific chromosome aneuploidy (trisomy 13, 15 or 18) and in each case our microarray analysis was able to obtain a diagnosis based on the fact that the aneuploid chromosome gave the highest ratio (1.32, 1.27 and 1.27 respectively) with the ratios of all other chromosomes falling within the range 0.75-1.25. Requiring just 30 h, our method may be more suitable for PGD aneuploidy screening than metaphase CGH.

DNA microarray analysis of gene expression profiles in deep endometriosis using laser capture microdissection.

Abstract: Endometriosis, a common gynecological disorder that causes infertility and pelvic pain, is defined as the presence of endometrial glands and stroma within extra-uterine sites. However, despite extensive studies its etiology and pathogenesis are not completely understood. Differentially expressed genes were investigated in epithelial and stromal cells from deep endometriosis and matched eutopic endometrium using cDNA microarrays and laser capture microdissection. Validation of results of several up- and down-regulated genes was performed by quantitative real-time RT ‐PCR. Our data showed that platelet-derived growth factor receptor alpha (PDGFRA), protein kinase C beta1 (PKC beta1) and janus kinase 1 (JAK1) were upregulated, and Sprouty2 and mitogen-activated protein kinase kinase 7 (MKK7) were downregulated in endometriosis stromal cells, suggesting the involvement of the RAS/RAF/MAPK signaling pathway through PDGFRA in endometriosis pathophysiology. In addition, two potential negative regulators of aromatase expression, chicken ovalbumin upstream promoter transcription factor 2 (COUP-TF2) and prostaglandin E2 receptor subtype EP3 (PGE2EP3), were downregulated in endometriosis epithelial cells, which might result in increased local production of estrogen in endometriosis epithelial cells. Furthermore, three potential candidate genes that might be involved in endometriosis related pain were identified: tyrosine kinase receptor B (TRkB) in endometriosis epithelial cells, and serotonin transporter (5HTT) and mu opioid receptor (MOR) in endometriosis stromal cells were all upregulated. One of the candidate genes, MOR, may be involved in a defective immune system in endometriosis. This study has provided new insights into endometriosis pathophysiology.

Membrane-bound HLA-G activates proliferation and interferon-gamma production by uterine natural killer cells.

Abstract: The expression of HLA-G by invading trophoblasts suggests a role for this molecule in embryo implantation. Putative targets for HLA-G are the uterine natural killer cells (uNK) that are abundantly present at the time of implantation. Since NK cells are potent producers of a variety of cytokines, interaction with HLA-G may result in the production of cytokines involved in trophoblast differentiation or tissue remodelling. In the present study we investigated the effect of membrane-bound HLA-G (mHLA-G) on the uterine mononuclear cell population (UMC) as a whole and on uNK cells in particular by measuring proliferation and cytokine production [interferon-gamma (IFN-gamma)/vascular endothelial growth factor (VEGF)/leukaemia inhibitory factor (LIF)/interleukin-3 (IL-3)]. Uterine cells were isolated from endometrium of non-pregnant women at the time that the endometrium is thought to be receptive to implantation, and then co-cultured with HLA-class I(-)/HLA-class II(+) 721.221 B-LCL cells transfected with mHLA-G. HLA-G suppressed the alloproliferative response of unfractionated UMC to 721.221 cells. Also, IFN-gamma and IL-3 production was strongly reduced. In contrast, purified uNK cells were stimulated by mHLA-G. Proliferation as well as IFN-gamma production was increased after co-culture with mHLA-G transfected 721.221 cells. HLA-G stimulated VEGF production by UMC as well as purified uNK cells. LIF-levels were below the detection level of our enzyme-linked immunosorbent assay. In conclusion, our data show that mHLA-G stimulates proliferation and cytokine production by NK cells, while down-modulating the response of unfractionated UMC.

Rapid prenatal diagnosis of common chromosome aneuploidies by QF-PCR. Assessment on 18 000 consecutive clinical samples

Abstract: The quantitative fluorescent PCR (QF-PCR) assay, introduced during the last few years, allows prenatal diagnoses of common chromosome aneuploidies in a few hours after sampling. We report the first assessment of QF-PCR performed on a large cohort of 18,000 consecutive clinical specimens analysed in two different Centres. All samples were analysed by QF-PCR using several selected STR markers together with amelogenin and, occasionally, SRY for fetal sexing. Results were compared with those obtained by conventional cytogenetic analysis. In 17,129 tests, normal fetuses were detected by QF-PCR. No false positives were observed. All 732 cases of trisomy 21, 18, 13, triploidies, double trisomies as well as all but one fetuses with X and Y aneuploidies were correctly diagnosed. Chromosome mosaicism could also be suspected in several samples. In some cases of in vitro culture failures, QF-PCR was the only evidence of fetal X, Y, 21, 18 and 13 chromosome complement. QF-PCR proved to be efficient and reliable in detecting major numerical chromosome disorders. The main advantages of the molecular assay are its very low cost, speed and automation enabling a single operator to perform up to 40 assays per day. QF-PCR relieves anxiety of most parents within 24 h from sampling and accelerates therapeutic interventions in the case of an abnormal result. In countries where large scale conventional cytogenetics is hampered by its high cost and lack of technical expertise, QF-PCR may be used as the only prenatal diagnostic test.

Polymorphisms of genes involved in innate immunity: association with preterm delivery

Abstract: An altered inflammatory activity due to functionally relevant polymorphisms of the innate immune system may influence pathways leading to labour and, therefore, impact on the frequency of preterm birth. We examined five polymorphisms of the innate immune system in a large cohort of preterm very-low-birth-weight (VLBW, n = 909) and term-born infants (n = 491) and their mothers (n = 747). The primary outcome was preterm versus term birth. Frequencies of polymorphisms in mothers of term-born infants versus mothers of VLBW infants and term infants versus preterm VLBW infants (singletons) are given. Homozygous CD14-159T: 18.5 versus 21.8% (mothers) and 19.6 versus 21.2% (infants). Homozygous interleukin IL-6-174G: 28.8 versus 38% (P = 0.018, mothers) and 30 versus 32.7% (infants). Homozygous or heterozygous nuclear oligomerization domain NOD2-3020insC: 6.9 versus 6.1% (mothers) and 5.7 versus 5.1% (infants). Heterozygous or homozygous toll-like-receptor TLR2-Arg753Gln: 6.9 versus 6.1% (mothers) and 5.7 versus 5.1% (infants). Homozygous or heterozygous TLR4-896G: 8.1 versus 11.5% (mothers) and 11.6 versus 10.5% (infants). Although the homozygous maternal IL-6-174G genotype was found to be independently associated with preterm delivery in multivariate regression analysis, the incidence of intrauterine infection was not significantly increased in mothers of preterm VLBW-infants, carrying this or other polymorphisms of the innate immune system. The overall influence of the investigated polymorphisms on the development of preterm delivery seems moderate, since only the maternal IL6-174G genotype was associated with preterm birth and none of the polymorphisms were associated with intrauterine infection as the cause of preterm birth.

Mechanical stretch activates type 2 cyclooxygenase via activator protein-1 transcription factor in human myometrial cells.

Abstract: The uterus is subject to stretch throughout pregnancy, which, in the presence of progesterone, is a potent stimulus for uterine growth. However, in the absence of progesterone or when stretch is excessive, as in multiple pregnancy, it may provoke the onset of labour. We have investigated the effect of stretch on prostaglandin synthesis in primary human uterine myocytes [nonpregnant (NP), pregnant not in labour (NL) and pregnant in labour (L)]. The cells were grown on flexible bottom culture plates and subjected to 1 or 6 h static stretch. Expression of type 2 cyclooxygenase (COX-2) mRNA was similar in samples obtained from NP and L groups and both were significantly greater than those found in the NL group. Stretch of cells from all groups resulted in increased COX-2 mRNA expression. In further studies carried out on cells taken from the NL group, 6 h of stretch resulted in increased COX-2 protein levels and, in the media, increases in prostaglandin (PG) I2 metabolite and PGE2 concentrations and a reduction in the concentration of PGF2a metabolites. After stretch, EMSA studies showed increased activator protein-1 (AP-1) nuclear protein DNA binding activity but not of nuclear factor kB. These data demonstrate that stretch of human myocytes results in increased COX-2 activity and suggest that this may occur through activation of the AP-1 system.

Phosphorylation of the Arginine-X-X-(Serine/Threonine) motif in human sperm proteins during capacitation: modulation and protein kinase A dependency.

Abstract: Sperm capacitation is a complex process that involves a protein kinase A (PKA)-dependent tyrosine phosphorylation of proteins. We studied the time-course, the modulation and the cellular localization of the phosphorylation of the Arginine-X-X-(Serine/ Threonine) motif, characteristic of PKA substrates, in sperm proteins during capacitation. There was an increased phosphorylation of 80 (p80) and 105 (p105) kDa protein bands in human sperm treated with different capacitation inducers. Phosphorylation of p80 and p105 induced by fetal cord serum ultrafiltrate or the combination of 3-isobutyl-1-methylxanthine and dibutyryl cAMP was prevented by H89 and Rp-adenosine-3¢,5¢-cyclic monophosphorothionate, confirming the involvement of PKA in this effect. Inhibitors of protein kinase C, receptor type tyrosine kinase and mitogen-activated protein kinase kinase did not affect the Arginine-X-X-(Serine/Threonine) motif phosphorylation. Non-receptor type protein tyrosine kinase inhibitors, PP2 and herbimycin A, enzymatic antioxidants and a nitric oxide synthase inhibitor prevented the phosphorylation of p80 and p105 when sperm were incubated with fetal cord serum ultrafiltrate. The phosphorylated Arginine-X-X-Serine/Threonine motif was immunolocalized all along the flagellum and the fluorescent signal was higher in capacitating than in non-capacitating sperm. These results show for the first time the presence of a PKA-dependent phosphorylation of proteins in human sperm capacitation and its upstream modulation by reactive oxygen species and non-receptor type protein tyrosine kinase.

Androgen receptor gene CAG and GGC repeat lengths in idiopathic male infertility.

Abstract: The androgen receptor (AR) has two polymorphic sites in exon 1, characterized by different numbers of CAG and GGC repeats resulting in variable lengths of polyglutamine and polyglycine stretches. Longer CAG repeats result in a reduced AR transcriptional activity, whereas the role of the GGC triplets is less clear. A relationship between decreased spermatogenesis and moderate expansion in the CAG tract has been found in some studies, but not in others. Furthermore, the joint distribution of CAG and GGC repeats in male infertility has never been reported before. We analysed CAG and GGC repeat lengths in a group of 163 men with idiopathic infertility compared with 115 fertile normozoospermic men. No difference was found between patients and controls in the mean and median values, and in distribution of CAG and GGC, when considered separately. However, the analysis of the joint distribution of CAG and GGC showed that the distribution of particular haplotypes is significantly different between patients and controls. In particular, two CAG/GGC haplotypes seem to increase susceptibility to infertility (CAG = 21/GGC = 18 and CAG >/=21/GGC >/=18, relative risk 2.47 and 1.6), while one haplotype (CAG >/=23/GGC

Development and clinical application of a strategy for preimplantation genetic diagnosis of single gene disorders combined with HLA matching.

Abstract: Preimplantation HLA matching has recently emerged as a tool for couples desiring to conceive a potential donor progeny for transplantation in a sibling with a life-threatening disorder. In this paper we describe a strategy optimized for preimplantation genetic diagnosis (PGD) of haemoglobinopathies combined with HLA matching. This procedure involves a minisequencingbased genotyping of HLA regions A, B, C and DRB combined with mutation analysis of the gene regions involved by mutation. Analysis of at least eight polymorphic short tandem repeat (STR) markers scattered through the HLA complex has also been included to detect potential contamination and crossing-over occurrences between HLA genes. The above assay can also be used for preimplantation HLA matching as a primary indication. The strategy was clinically applied for HLA matching in 17 cycles (14 for b-thalassaemia, one for Wiscott‐Aldrich syndrome and two for leukaemia). A reliable HLA genotype was achieved in 255/266 (95.9%) of the blastomeres. In total, 22 (14.8%) embryos were obtained that were HLA-matched with the affected siblings, 14 (9.4%) of which were unaffected and transferred back to the patients. Four clinical pregnancies were obtained, three of which (one twin, two singletons) are ongoing and were confirmed as healthy and HLA-identical with the affected children. Minisequencing-based HLA typing combined with HLA STR haplotyping has been shown to be a reliable strategy for preimplantation HLA matching. The major advantage of this approach is that the validation of a single assay can be done once and then used for the majority of the patients, reducing notably time needed for preclinical set-up of each case.

The parent-of-origin effect of 10q22 in pre-eclamptic females coincides with two regions clustered for genes with down-regulated expression in androgenetic placentas

Abstract: By affected sib-pair linkage analysis of 24 families with pre-eclampsia, we confirm a susceptibility locus on chromosome 10q22.1 in Dutch females: a multipoint non-parametric linkage score of 3.6 near marker D10S1432 was obtained. Haplotype analysis showed a parent-of-origin effect: maximal allele sharing in the affected sibs was found for maternally derived alleles in all families, but not for the paternally derived alleles. As matrilineal inheritance suggests the presence of maternally expressed imprinted genes, while imprinting operates predominantly in (extra)embryonic tissues, all genes (n = 132) known on 10q22 between GATA121A08 and D10S580 were screened for seven sequence-related features associated with imprinting and subsequently tested for expression in first trimester placenta. Placental expression of genes selected in this way (n = 55) was compared with expression in androgenetic placentas of identical gestational age. Two regions on 10q22 were identified with developmentally co-repressed genes with non-random chromosomal distribution. Interestingly, these two clusters, near CTNNA3 and KCNMA1 and each containing five genes with down-regulated expression in androgenetic placentas, coincided with the regions with maximal maternal allele sharing seen in the pre-eclamptic sisters. Our linkage and expression data are compatible with the concept that pre-eclampsia involves maternally expressed imprinted genes that operate in the first trimester placenta.

Gonadotrophin-induced gene regulation in human granulosa cells obtained from IVF patients. Modulation of steroidogenic genes, cytoskeletal genes and genes coding for apoptotic signalling and protein kinases.

Abstract: Gonadotrophins exert a major effect on ovarian development and on the control of fertilization. By stimulating cells with forskolin (FK), it is possible to study which genes are activated by gonadotrophins via the cAMP cascade, and which by alternative pathways. Using RNA isolated from stimulated cells, we found that 59% of the total genes modulated by LH were also modulated by FK, while 69% of the genes modulated exclusively by FSH were also modulated by FK. Gene transcripts involved in steroidogenesis/progesterone production were highly elevated, while 17beta-hydroxysteroid dehydrogenase was down-regulated. This suggests that a decrease in the conversion of androstenedione to testosterone and estrone to estradiol occurs during luteinization. Down-regulation of genes coding for actin cytoskeleton proteins and cytokeratin 18 was observed in response to gonadotrophin and cAMP stimulation. Several of the genes coding for the microtubule network were also modulated, implying that rearrangement of the cytoskeletal proteins permits better coupling between organelles involved in steroidogenesis. A dramatic change in gene transcripts coding for signalling enzymes was observed following LH stimulation. This includes the down-regulation of adenylyl cyclase 7 and 9, elevation of cAMP-dependent phosphodiesterase, and the up-regulation of a negative regulator of G-protein signalling (RGS16) that may negate gonadotrophin signalling via guanine nucleotide binding proteins. Thus luteinized cells, despite increased gene transcripts to LH/chorionic gonadotrophin (CG) receptors, respond inefficiently to gonadotrophin stimulation, due to attenuation of signal transduction in the cAMP cascade at multiple steps. Novel genes involved in the regulation of apoptosis were found for the first time to be up-regulated by gonadotrophin stimulation, including: BAX inhibitor-1, granulysin and apoptosis repressor with caspase recruitment domain (ARC). These proteins may be involved in a unique alternative pathway of ovarian cell death. Such a pathway could temporarily preserve the mitochondria and progesterone production during the initial stages of granulosa cell apoptosis.

Vascular endothelial growth factor, epidermal growth factor and fibroblast growth factor-4 and -10 stimulate trophoblast plasminogen activator system and metalloproteinase-9

Abstract: Trophoblast invasion, accompanied by degradation of extracellular matrix, is crucial to normal pregnancy development, whereas shallow placental invasion and implantation likely plays a role in the subsequent development of pre-eclampsia. The growth factors vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and fibroblast growth factor (FGF) are placental growth factors that activate degradation of extracellular matrix. We determined the effect of VEGF, EGF, FGF-2, FGF-4 and FGF-10 on the plasminogen activator system of first trimester cytotrophoblasts cultured in vitro. We studied the activity of urokinase plasminogen activator (uPA), its inhibitor plasminogen activator inhibitor-1 (PAI-1), and 92 kDa gelatinase-B (matrix metalloproteinase-9, MMP-9), using protein gel and reversed gel zymography. The expression pattern of FGF-4 and FGF-10 in human placental sections was determined by immunohistochemistry. FGF-4 was expressed in first trimester villi stroma, primarily in endothelial cells. FGF-10 expression was localized to first trimester extravillous trophoblasts. VEGF, EGF, FGF-4 and FGF-10, but not FGF-2, stimulate the activity of trophoblast uPA, PAI-1 and MMP-9. These results support the hypothesis that specific growth factors modulate the invasive potential of trophoblasts, and therefore may play an important role in early placental development. Our findings may contribute to the understanding of the pathophysiology of diseases associated with shallow placentation, such as pre-eclampsia.