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van de Looij A, Singh R, Hatt L, Ravn K, Jeppesen LD, Nicolaisen BH, Kølvraa M, Vogel I, Schelde P, Uldbjerg N. Do fetal extravillous trophoblasts circulate in maternal blood postpartum? Acta Obstet Gynecol Scand 2020; 99:751-756. [PMID: 32323316 PMCID: PMC7384123 DOI: 10.1111/aogs.13880] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 04/17/2020] [Accepted: 04/20/2020] [Indexed: 02/01/2023]
Abstract
Introduction Circulating fetal extravillous trophoblasts may offer a superior alternative to cell‐free fetal DNA for noninvasive prenatal testing. Cells of fetal origin are a pure source of fetal genome; hence, unlike the cell‐free noninvasive prenatal test, the fetal cell‐based noninvasive prenatal test is not expected to be affected by maternal DNA. However, circulating fetal cells from previous pregnancies may lead to confounding results. Material and methods To study whether fetal trophoblast cells persist in maternal circulation postpartum, blood samples were collected from 11 women who had given birth to a boy, with blood sampling at 1‐3 days (W0), 4‐5 weeks (W4‐5), around 8 weeks (W8) and around 12 weeks (W12) postpartum. The existence of fetal extravillous trophoblasts was verified either by X and Y chromosome fluorescence in situ hybridization analysis or by short tandem repeat analysis. To exclude technological bias in isolating fetal cells, blood samples were also collected from 10 pregnant women between a gestational age of 10 and 14 weeks, the optimal time frame for cell‐based noninvasive prenatal test sampling. All the samples were processed according to protocols established by ARCEDI Biotech for fetal extravillous trophoblast enrichment and isolation. Results Fetal extravillous trophoblasts were found in all the 10 samples from pregnant women between a gestational age of 10 and 14 weeks. However, only 4 of 11 blood samples taken from women at 1‐3 days postpartum rendered fetal extravillous trophoblasts, and only 2 of 11 samples rendered fetal extravillous trophoblasts at 4 weeks postpartum. Conclusions In this preliminary dataset on few pregnancies, none of the samples rendered any fetal cells at or after 8 weeks postpartum, showing that cell‐based noninvasive prenatal testing based on fetal extravillous trophoblasts is unlikely to be influenced by circulating cells from previous pregnancies.
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Affiliation(s)
- Anne van de Looij
- Department of Women's Disease and Birth, Aarhus University Hospital, Aarhus, Denmark
| | | | | | | | | | | | | | - Ida Vogel
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | | | - Niels Uldbjerg
- Department of Women's Disease and Birth, Aarhus University Hospital, Aarhus, Denmark
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Tan KH, Zeng XX, Sasajala P, Yeo A, Udolph G. Fetomaternal microchimerism: Some answers and many new questions. CHIMERISM 2017; 2:16-8. [PMID: 21547031 DOI: 10.4161/chim.2.1.14692] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Accepted: 12/20/2010] [Indexed: 01/27/2023]
Abstract
The transfer of fetal cells into mothers during pregnancy and their organ specific integration is a well recognized phenomenon in placental vertebrates. Recently, it has been reported that some fetal cells found in the mothers have progenitor cell-like features such as multilineage differentiation potential and as a consequence they were termed pregnancy associated progenitor cells (PAPC). The multilineage differentiation potential suggested some level of cellular plasticity, which these cells share with other stem or progenitor cells. In this context, we have shown that PAPCs indeed express neural stem cell and markers for developing neurons in the brain and that PAPCs morphologically mature into neurons over time. The stem/progenitor properties of PAPCs raises the hope that they might be valuable for studying the functional integration of foreign cells into preexisting tissues and organs, for example in cellular therapies. The functional integration of transplanted cells and their connectivity to the host circuitry is still a major bottleneck in cellular therapies particularly for the brain. The animal models of fetomaternal microchimerism might provide valuable insights into the mechanism how cells survive, migrate, integrate and differentiate in a foreign environment of a host. This review discusses some of the recent findings in the field of fetomaternal microchimerism. It also tries to identify some major gaps of knowledge and raises some questions resulting from the recent advances. Studying fetomaternal microchimerism and the properties of PAPCs in greater detail might pave the way to advance cell based regenerative medicine as well as transplantation medicine.
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Tsui DW, Chiu RW, Lo YD. Epigenetic approaches for the detection of fetal DNA in maternal plasma. CHIMERISM 2017; 1:30-5. [PMID: 21327153 DOI: 10.4161/chim.1.1.12439] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Accepted: 05/20/2010] [Indexed: 12/18/2022]
Abstract
The presence of fetal DNA in the plasma of pregnant women has opened up new possibilities for noninvasive prenatal diagnosis. Over the past decades, different types of fetal markers have been developed, initially based on discriminative genetic markers such as male-specific signals or paternally-inherited polymorphisms, and gradually evolved to the detection of fetal-specific transcripts or epigenetic signatures. This development has extended the coverage of the application of cell-free fetal DNA to essentially all pregnancies, regardless of the gender of the fetus or its polymorphic status. In this review, we present an overview of the development of noninvasive prenatal diagnosis through epigenetics. We introduce the basis of how fetal DNA could be detected from a large background of maternal DNA in maternal plasma based on fetal-specific DNA methylation patterns. We evaluate the methodologies involved and discuss the factors that affect the robustness of the detection. We review the progress in adopting fetal epigenetic markers for noninvasive prenatal assessment of fetal chromosomal aneuploidies and pregnancy-associated disorders. We conclude with comments on the future directions regarding the search for new fetal epigenetic markers and the clinical implementation of epigenetic approaches for noninvasive prenatal diagnosis.
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Affiliation(s)
- Dana Wy Tsui
- The Centre for Research into Circulating Fetal Nucleic Acids; Li Ka Shing Institute of Health Sciences; and Department of Chemical Pathology; The Chinese University of Hong Kong; Shatin, Hong Kong SAR China
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Tan KH, Zeng XX, Sasajala P, Yeo A, Udolph G. Fetomaternal microchimerism. CHIMERISM 2014. [DOI: 10.4161/chim.14692] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Hua R, Barrett AN, Tan TZ, Huang Z, Mahyuddin AP, Ponnusamy S, Sandhu JS, Ho SSY, Chan JKY, Chong S, Quan S, Choolani M. Detection of aneuploidy from single fetal nucleated red blood cells using whole genome sequencing. Prenat Diagn 2014; 35:637-44. [PMID: 25178640 DOI: 10.1002/pd.4491] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 08/26/2014] [Accepted: 08/27/2014] [Indexed: 12/16/2022]
Abstract
OBJECTIVE The objective of the study was to detect aneuploidy in single fetal nucleated red blood cells (FNRBCs) from placental villi using whole genome amplification (WGA) and next generation sequencing. METHODS Three single FNRBCs per sample were manually picked from villi collected from ten women undergoing elective first-trimester termination of pregnancy, and one or two cells were picked from each of four aneuploid chorionic villus samples. Following WGA and addition of adaptor and index sequences, samples were sequenced on the Illumina MiSeq. Leading and trailing 15 bases were trimmed, and reads were aligned to the human reference genome. Z-scores were calculated to determine deviation of the mean of the test from reference samples, with a score of 3 used as the threshold for classification of a particular chromosome as trisomic. RESULTS We successfully made correct diagnoses from ten single cells isolated from villi from two cases of trisomy 21 (one case from a single cell and one from two cells), two cases of trisomy 18 (two cells each), and a case of trisomy 15 (three cells). CONCLUSION With their faithful representation of fetal genome, diagnosis using single FNRBCs provides a definitive result compared with non-invasive prenatal testing using cell-free fetal DNA, and is a safer alternative to invasive amniocentesis.
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Affiliation(s)
- Rui Hua
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228.,Department of Obstetrics and Gynaecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Angela N Barrett
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228
| | - Tuan Zea Tan
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, S117599
| | - Zhouwei Huang
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228
| | - Aniza Puteri Mahyuddin
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228
| | - Sukumar Ponnusamy
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228
| | - Jaspal Singh Sandhu
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228
| | - Sherry S Y Ho
- Department of Laboratory Medicine, Molecular Diagnosis Centre, National University Hospital, Singapore, S119074
| | - Jerry K Y Chan
- Experimental Fetal Medicine Group, Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228.,Department of Reproductive Medicine, KK Women's and Children's Hospital, Singapore, S229899
| | - Samuel Chong
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University Hospital, National University of Singapore, Singapore, S119074
| | - Song Quan
- Department of Obstetrics and Gynaecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Mahesh Choolani
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228
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Bussani C, Scarselli B, Cioni R, Bucciantini S, Scarselli G. Use of the Quantitative Fluorescent-PCR Assay in the Study of Fetal DNA from Micromanipulated Transcervical Samples. ACTA ACUST UNITED AC 2012; 8:259-63. [PMID: 15887982 DOI: 10.1007/bf03260071] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
AIM The purpose of this study was to evaluate the validity of the combined use of micromanipulation and quantitative fluorescent (QF)-PCR assay for the identification of fetal elements in transcervical cell (TCC) samples collected in early pregnancy. METHODS TCC samples were obtained by intrauterine lavage (IUL) in 113 pregnant women who were between 7 and 12 weeks pregnant before termination of pregnancy. All IUL samples were screened under an inverted microscope, at which time the isolation of fetal cells by micromanipulation was attempted. QF-PCR assay, using 9 small tandem repeat (STR) markers for chromosomes 13, 18, 21, X, and Y, was performed in all specimens to identify fetal cells in TCC samples and the corresponding placental tissue and blood specimens. TCC samples from male fetuses in which either the micromanipulation or QF-PCR analysis were unsuccessful, were studied with fluorescent in situ hybridization (FISH), using probes for X and Y chromosomes. RESULTS Isolation of supposed fetal material from IUL samples was carried out by means of micromanipulation in 93 cases (82.3%), where discernible chorionic villous filaments or cell clumps of probable trophoblastic origin were present. The QF-PCR analysis was performed in all 93 IUL samples and paternal peaks could be documented in 88 cases (94.6%) thus confirming the presence of fetal cells. Thirteen cases negative to micromanipulation and derived from male fetuses and four male cases not informative with QF-PCR analysis, after micromanipulation, were then tested with FISH assay using probes for sexual chromosomes. In six samples, rare (2-3%) male fetal cells were detected. Considering the combined results obtained from QF-PCR and FISH assays, the overall fetal sexing was correct in 83.2% of cases (94 of 113). CONCLUSION This study provides evidence that fetal cells are present in a high proportion of IUL samples. Micromanipulation appears to be an extremely efficient method for the isolation of trophoblastic elements. This study also confirms the potential of IUL as a possible alternative to the traditional prenatal diagnostic procedures for the recovery of fetal cells in precocious stage of gestation, and validates the combination of the isolation of such fetal elements by means of micromanipulation and analysis with the QF-PCR assay for the identification of the most frequent prenatal chromosomal aneuploidies.
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Affiliation(s)
- Cecilia Bussani
- Department of Gynecology, Perinatology and Human Reproduction, University of Florence, Florence, Italy.
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Cell-free fetal nucleic acid testing: a review of the technology and its applications. Obstet Gynecol Surv 2012; 66:431-42. [PMID: 21944155 DOI: 10.1097/ogx.0b013e31822dfbe2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
UNLABELLED Cell-free fetal nucleic acids circulating in the blood of pregnant women afford the opportunity for early, noninvasive prenatal genetic testing. The predominance of admixed maternal genetic material in circulation demands innovative means for identification and analysis of cell-free fetal DNA and RNA. Techniques using polymerase chain reaction, mass spectrometry, and sequencing have been developed for the purposes of detecting fetal-specific sequences, such as paternally inherited or de novo mutations, or determining allelic balance or chromosome dosage. Clinical applications of these methods include fetal sex determination and blood group typing, which are currently available commercially although not offered routinely in the United States. Other uses of cell-free fetal DNA and RNA being explored are the detection of single-gene disorders, chromosomal abnormalities, and inheritance of parental polymorphisms across the whole fetal genome. The concentration of cell-free fetal DNA may also provide predictive capabilities for pregnancy-associated complications. The roles that cell-free fetal nucleic acid testing assume in the existing framework of prenatal screening and invasive diagnostic testing will depend on factors such as costs, clinical validity and utility, and perceived benefit-risk ratios for different applications. As cell-free fetal DNA and RNA testing continues to be developed and translated, significant ethical, legal, and social questions will arise that will need to be addressed by those with a stake in the use of this technology. TARGET AUDIENCE Obstetricians & Gynecologists and Family Physicians Learning Objectives: After participating in this activity, physicians should be better able to evaluate techniques and tools for analyzing cell-free fetal nucleic acids, assess clinical applications of prenatal testing, using cell-free fetal nucleic acids and barriers to implementation, and distinguish between relevant clinical features of cell-free fetal nucleic acid testing and existing prenatal genetic screening and diagnostic procedures.
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Cell-free fetal DNA in the non-pregnant woman with thyroid disease disappeared after surgery. Clin Chim Acta 2008; 397:101-2. [PMID: 18682249 DOI: 10.1016/j.cca.2008.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2008] [Revised: 07/08/2008] [Accepted: 07/08/2008] [Indexed: 11/24/2022]
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Bussani C, Cioni R, Mattei A, Fambrini M, Marchionni M, Scarselli G. Prenatal diagnosis of common aneuploidies in transcervical samples using quantitative fluorescent-PCR analysis. Mol Diagn Ther 2007; 11:117-21. [PMID: 17397248 DOI: 10.1007/bf03256231] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
AIM The aim of this study was to test the feasibility of diagnosing common fetal chromosomal aneuploidies using quantitative fluorescent (QF)-PCR on transcervical cell (TCC) samples collected in the first trimester of pregnancy by means of intrauterine lavage (IUL). METHODS A total of 181 TCC samples were retrieved from pregnant women between 5 and 12 weeks of gestation, immediately before elective termination of pregnancy, at which time corresponding placental tissue and maternal blood specimens were also obtained. Isolation of trophoblastic cells by micromanipulation was attempted in all TCC samples. Micromanipulated specimens were analyzed by multiplex QF-PCR, including short tandem repeats for the chromosomes X, Y, 21, 18, and 13. RESULTS The micromanipulation was successful in 152 of 181 cases (84.8%) where chorionic villous filaments and/or cell clumps of seeming trophoblastic origin could be isolated. All 152 samples were tested by QF-PCR analysis and peaks of paternal origin could be documented in all cases. Two cases of trisomy 21 and two cases of monosomy X0 were detected by means of QF-PCR assay, in accordance with the results obtained in corresponding placental samples. CONCLUSION This study provides evidence that the use of multiplex QF-PCR amplification of selected microsatellites could be applied to micromanipulated TCC samples and in particular to IUL samples, which often contain trophoblastic cells, for the detection of chromosomal aneuploidies. The approach described in this study appears, therefore, a very promising tool toward non-invasive prenatal genetic diagnosis in the early stage of gestation.
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Affiliation(s)
- Cecilia Bussani
- Department of Gynecology, Perinatology and Human Reproduction, University of Florence, Florence, Italy.
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Loren AW, Bunin GR, Boudreau C, Champlin RE, Cnaan A, Horowitz MM, Loberiza FR, Porter DL. Impact of Donor and Recipient Sex and Parity on Outcomes of HLA-Identical Sibling Allogeneic Hematopoietic Stem Cell Transplantation. Biol Blood Marrow Transplant 2006; 12:758-69. [PMID: 16785065 DOI: 10.1016/j.bbmt.2006.03.015] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2006] [Accepted: 03/27/2006] [Indexed: 11/16/2022]
Abstract
Allogeneic hematopoietic stem cell transplantation (SCT) may cure patients with hematologic malignancies, but it carries significant risks. Careful donor selection is an important component of the clinical transplantation decision-making process and includes evaluation of HLA typing and other criteria, the most controversial of which is parity. We examined the effect of donor sex and parity on outcomes of HLA-identical sibling SCT. Because the effect of recipient sex/parity has never been explicitly evaluated, we also analyzed the effect of recipient sex/parity on outcomes of transplantation. We found that (1) parous female donors result in an increased risk of chronic graft-versus-host disease (GVHD) in all recipients, (2) the magnitude of this increased risk is similar in male and female recipients, and (3) nulliparous female donors increase the risk of chronic GVHD in male recipients to a degree comparable to that from parous donors. A decrease in the risk of relapse was not observed, and there was no effect on overall survival, acute GVHD, or transplant-related mortality. Recipient parity had no independent effect on any endpoint. Until the effects of pregnancy on the maternal immune system are better understood, it is appropriate whenever possible to avoid parous female donors and to choose male donors for male recipients in HLA-identical related donor SCT.
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Affiliation(s)
- Alison W Loren
- Stem Cell Transplant Program, Abramson Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
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Krabchi K, Gadji M, Forest JC, Drouin R. Quantification of all fetal nucleated cells in maternal blood in different cases of aneuploidies. Clin Genet 2006; 69:145-54. [PMID: 16433695 DOI: 10.1111/j.1399-0004.2005.00564.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We quantified all fetal nucleated cells (FNCs) per unit volume of maternal blood in different aneuploid pregnancies using molecular cytogenetic techniques. Seven cases of male trisomy 18, two triploidies (69,XXX), two 47,XXX, one 47,XXY, one 47,XYY, one male trisomy 13, and one case of 47,XY,r(22),+r(22) were analyzed. Whole blood samples were obtained from 15 women between 17 and 29 gestational weeks and harvested without using fetal cell enrichment procedures. Fluorescence in situ hybridization and primed in situ labeling were performed to identify the FNCs. All slides were manually scanned to quantify those cells. We have identified 4-20 FNCs/ml of maternal blood in the cases of trisomy 18; 10 and 25 FNCs/ml in the two cases of triploidy; 16 and 14 FNCs/ml, respectively, in the two X trisomies; 19 FNCs/ml in the 47,XXY; 26 FNCs/ml in the 47,XYY; nine FNCs/ml in the trisomy 13; and 10 FNCs/ml in the case of r(22). To detect all FNCs in all aneuploid pregnancies, we have used a very simple method that minimizes the manipulation steps to avoid losing fetal cells. The number of FNCs identified in aneuploid pregnancies was 2-5 times higher than in normal pregnancies. This higher number of FNCs will favor the design of a non-invasive pre-natal test.
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Affiliation(s)
- K Krabchi
- Service of Genetics, Department of Pediatrics, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC, Canada
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Troeger C, Holzgreve W, Ladewig A, Zhong XY, Hahn S. Examination of Maternal Plasma Erythropoietin and Activin A Concentrations with Regard to Circulatory Erythroblast Levels in Normal and Preeclamptic Pregnancies. Fetal Diagn Ther 2005; 21:156-60. [PMID: 16354996 DOI: 10.1159/000089068] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2005] [Accepted: 05/25/2005] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Preeclampsia has been shown to be associated with an increased number of fetal and maternal erythroblasts in the maternal circulation, suggesting that preeclampsia involves increased leakage of fetal cells across the placental barrier, as well as increased erythropoiesis. We examined the relationship between circulatory erythroblast levels with maternal plasma concentrations of erythropoietin and activin A. METHODS In a case-control study, we examined 15 pregnancies affected by preeclampsia and 10 matched controls. Erythroblasts were enriched from maternal blood samples by magnetic cell sorting, enumerated and correlated with corresponding plasma activin A and erythropoietin concentrations. RESULTS The proportion of erythroblast was elevated in preeclampsia (0.8 vs. 0.1%, p = 0.023). Erythropoietin and activin A concentrations were significantly elevated in preeclampsia (100.4 vs. 44.5 pg/ml, p = 0.023, and 7.4 vs. 1.85 ng/ml, p = 0.029, respectively). Circulatory erythroblast numbers were found to correlate with plasma activin A concentrations (r = 0.76, p = 0.01) in cases with preeclampsia. No such relationship existed for erythropoietin. CONCLUSIONS Our data suggest that increased concentrations of activin A promote enhanced levels of erythropoiesis in preeclampsia. As the placenta is one of the major sources of activin A in pregnancy, this increase in activin A-dependent erythropoiesis in preeclampsia may be a reflection of an underlying placental hypoxic condition.
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Affiliation(s)
- Carolyn Troeger
- University Women's Hospital and Department of Research, University Hospital, Basel, Switzerland
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Yang YH, Yang ES, Kwon JY, Kim IK, Park YW. Prenatal Diagnosis of Trisomy 21 with Fetal Cells in Maternal Blood Using Comparative Genomic Hybridization. Fetal Diagn Ther 2005; 21:125-33. [PMID: 16354990 DOI: 10.1159/000089062] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2004] [Accepted: 01/18/2005] [Indexed: 11/19/2022]
Abstract
OBJECTIVE This study was undertaken to determine the clinical use of comparative genomic hybridization (CGH) for detection of fetal trisomy 21 from fetal ceIls (nucleated red blood cells; nRBCs) isolated from maternal peripheral venous blood. METHODS Maternal peripheral venous blood samples were collected in sterile tubes containing heparin. After triple density gradient centrifugation, magnetic activated cell sorting using CD45 and CD71 was used to isolate the fetal nRBCs. Fetal nRBCs were successfully isolated from maternal peripheral blood in all cases. After laser-microdissecting fetal nRBCs, degenerate oligonucleotide-primed polymerase chain reaction, and nick translation, DNA size was suitable for hybridization. RESULTS By CGH analysis, we diagnosed one normal male, one normal female, and one trisomy 21 male fetus. These results were confirmed by amniocentesis. CONCLUSIONS Prenatal diagnosis from fetal cells in maternal peripheral blood by CGH shows clinical promise as an alternative or as a supplement to fluorescence in situ hybridization with chromosome-specific probes but further studies are warranted.
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Affiliation(s)
- Young Ho Yang
- Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul, Korea.
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Nomura K, Sumida Y, Yoh T, Morita A, Matsumoto Y, Taji S, Yoshida N, Minami M, Itoh Y, Horiike S, Kataoka K, Taniwaki M, Okanoue T. Lack of evidence for leukocyte maternal microchimerism in primary biliary cirrhosis. World J Gastroenterol 2004; 10:2415-6. [PMID: 15285032 PMCID: PMC4576301 DOI: 10.3748/wjg.v10.i16.2415] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
AIM: It is reasonable to assume that microchimerism could also be involved in the induction of primary biliary cirrhosis (PBC). However, previous reports investigated only fetus-microchimerism in women patients. Maternal microchimerism has not been investigated until now. The current study aimed to clear either maternal microchimerism was involved in the pathogenesis of PBC or not.
METHODS: We used fluorescence in situ hybridization on paraffin-embedded tissue (We called “Tissue-FISH”.) to determine whether maternal cells infiltrated in male patients who were diagnosed as having PBC. Tissue-FISH was performed by using both X and Y specific probes on the biopsy liver sample of 3 male PBC patients.
RESULTS: Infiltrating lymphocytes demonstrated both X and Y signals in all 3 male patients.
CONCLUSION: Maternal microchimerism dose not play a significant role in PBC. PBC may not relate to fetus and maternal microchimerism.
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Affiliation(s)
- Kenichi Nomura
- Molecular Hematology and Oncology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-0841, Japan.
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Sekizawa A, Yokokawa K, Sugito Y, Iwasaki M, Yukimoto Y, Ichizuka K, Saito H, Okai T. Evaluation of bidirectional transfer of plasma DNA through placenta. Hum Genet 2003; 113:307-10. [PMID: 12884005 DOI: 10.1007/s00439-003-0987-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2003] [Accepted: 06/03/2003] [Indexed: 11/27/2022]
Abstract
To clarify the origin of cell-free fetal DNA in maternal plasma, we analyzed bidirectional transfer of plasma DNA between fetus and mother. We analyzed maternal and fetal plasma DNA obtained from 15 pregnant women at the time of Cesarean section. The subjects were five patients with preeclampsia and 10 gestational-age-matched normal controls. DNA was extracted from 1.5-ml plasma samples and the cellular fraction of maternal and umbilical blood. Seven polymorphic marker genes were analyzed. The relative concentration of fetal DNA in maternal plasma and maternal DNA in cord blood were evaluated. The relative concentration of maternal DNA in fetal circulation (median, 0.9%; range, 0.2-8.4%) was significantly lower than that of fetal DNA in maternal blood (14.3%, 2.3-64%), with P=0.007. The relative concentration of maternal DNA in fetal blood was not affected by preeclampsia. These findings indicate that cell-free DNA is unequally transferred through the placenta. The structural characteristics of the placenta suggest that the majority of cell-free fetal DNA in maternal plasma is derived from villous trophoblasts.
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Affiliation(s)
- Akihiko Sekizawa
- Department of Obstetrics and Gynecology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, 142-8666, Tokyo, Japan.
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Abstract
This article reviews current information regarding the development and long-term effects on children born to women with connective tissue diseases. There are few data on specific effects attributed to the underlying maternal disease, but fetal growth restriction and preterm birth are relatively common. Antenatal use of prednisone as treatment for these disorders appears to be safe, and most children have developed normally. However, there is growing concern that prolonged fetal exposure to other glucocorticoids such as dexamethasone or betamethasone may lead to decreased growth and abnormal neuronal development. Low birth weight is reportedly associated with long-term medical complications such as adult-onset hypertension. Evidence also suggests that immunosuppressive agents taken during pregnancy might predispose the progeny to autoimmune disorders, malignancies and reproductive problems. Further research is warranted to determine that there are no unrecognized long-term risks to the offspring of these women.
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Affiliation(s)
- J R Scott
- Department of Obstetrics and Gynecology, University of Utah Medical Center, Salt Lake City 84108, USA.
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Abstract
Scleroderma is a heterogenous connective tissue disorder characterized by fibrosis of the skin, with or without internal organ involvement. The aetiology of scleroderma may involve both environmental and genetic factors. Abnormalities involving the immune system, vascular tissue and extracellular matrix have been demonstrated. Recent research has focused on microchimerism as a risk factor for the development of scleroderma. This article reviews the epidemiology and pathogenesis of this disorder.
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Affiliation(s)
- Keng Chen
- The St George Hospital, Kogarah, New South Wales, Australia.
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18
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Bussani C, Cioni R, Scarselli B, Barciulli F, Bucciantini S, Simi P, Fogli A, Scarselli G. Strategies for the isolation and detection of fetal cells in transcervical samples. Prenat Diagn 2002; 22:1098-101. [PMID: 12454965 DOI: 10.1002/pd.469] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE The aim of the study was to evaluate the detection of fetal cells from transcervical samples, collected in early pregnancy, by means of different molecular techniques. The value of the isolation of trophoblasts using an inverted microscope, also referred to as micromanipulation, is discussed. METHODS All the 89 specimens were obtained by intrauterine lavages before termination of pregnancy (TOP), between 7 and 12 weeks of gestation. Micromanipulation was carried out in a subgroup of 57 for the isolation of fetal material. Fetal sexing was achieved by FISH (fluorescent in situ hybridisation) using fluorescently labelled probes for X and Y chromosomes and by polymerase chain reaction (PCR). Male samples were also investigated for aneuploidy of the chromosome 21. Quantitative fluorescent (QF)-PCR using two short tandem repeat (STR) markers for chromosome 21 was carried out in 26 micromanipulated samples. RESULTS FISH analysis revealed that 45/89 placental samples derived from pregnancies with male fetuses. Correct sexing of the lavage samples from male pregnancies was achieved in 41/45 (91%) using dual-FISH technique, and in 43/45 (95.5%) with PCR. All the samples derived from male pregnancies tested for chromosome 21 were normal. From 57 samples subjected to micromanipulation, 51 (89.5%) showed discernible chorionic villous filaments or cell clumps of possible trophoblastic origin. One case of tetraploidy and two cases of monosomy were recorded. The rate of fetal cells, in the non-micromanipulated samples, was between 4% and 97% (mean 54.3%). In micromanipulated specimens, maternal contaminant cells were absent or extremely rare (1-2%). The efficiency of the QF-PCR analysis in detecting paternal peaks in all lavage samples was only 61.5%. CONCLUSION The present study confirms the presence of fetal cells in a very high proportion of both whole and micromanipulated intrauterine lavage samples. The isolation of trophoblastic elements can be achieved in most cases by micromanipulation. FISH and PCR techniques allowed the analysis of the most common fetal aneuploidies, confirming the power of this minimally invasive method.
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Affiliation(s)
- Cecilia Bussani
- Department of Gynecology, Perinatology and Human Reproduction, University of Florence, Florence, Italy.
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19
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Abstract
Microchimerism is defined by the presence within an individual of a low level of cells derived from another individual. Systemic sclerosis is clinically similar to chronic graft-versus-host disease, a known condition of chimerism, which has led some authors to explore the hypothesis that microchimerism may contribute to the pathogenesis of systemic sclerosis and other autoimmune disorders. This article reviews early studies that lend support to this hypothesis.
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Affiliation(s)
- S Régnier
- Unité de Dermatologie, Hôpital Tenon, 4 Rue de la Chine, 75020, Paris, France
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20
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Zitterkopf NL, Haven TR, Huela M, Bradley DS, Cafruny WA. Transplacental lactate dehydrogenase-elevating virus (LDV) transmission: immune inhibition of umbilical cord infection, and correlation of fetal virus susceptibility with development of F4/80 antigen expression. Placenta 2002; 23:438-46. [PMID: 12061860 DOI: 10.1053/plac.2002.0829] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Maternal-to-fetal transmission of the murine lactate dehydrogenase-elevating virus (LDV) has been previously shown to be regulated by maternal immunity as well as gestational age. For the present study, the role of maternal immunity in placental and umbilical cord virus protection was studied, and virus targeting of umbilical cord and fetal macrophages was correlated with expression of the F4/80 macrophage phenotypic marker. The results showed that LDV-infected macrophages appeared in umbilical cord by 24 h post-infection of pregnant mice, and some LDV-infected macrophages displayed the F4/80 phenotype. This potential reservoir of virus for the fetus was inhibited by passive immunization of pregnant mice with IgG anti-LDV antibodies, which rapidly concentrated in the placenta and umbilical cord. Probing of umbilical cord cells with antibodies directed at MHC genetic markers demonstrated the presence of both maternal and fetal cells in umbilical cords. A strong developmental correlation was observed between fetal F4/80 expression and LDV susceptibility, at about 13.6 days of gestation. These results demonstrate immune suppression of free and cell-associated virus in umbilical cord, thus defining a potentially important mechanism for immune protection of the fetus from transplacental virus infection. The results also clarify the developmental basis for fetal susceptibility to LDV infection.
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MESH Headings
- Animals
- Animals, Outbred Strains
- Antibodies, Viral/biosynthesis
- Antibodies, Viral/immunology
- Antigens, Differentiation/biosynthesis
- Antigens, Differentiation/immunology
- Arterivirus Infections/immunology
- Arterivirus Infections/transmission
- Disease Susceptibility/immunology
- Disease Susceptibility/virology
- Female
- Fetal Blood/immunology
- Fetal Blood/virology
- Fetal Diseases/immunology
- Fetal Diseases/virology
- Immunization, Passive
- Infectious Disease Transmission, Vertical
- Lactate dehydrogenase-elevating virus/immunology
- Lactate dehydrogenase-elevating virus/pathogenicity
- Lactate dehydrogenase-elevating virus/physiology
- Macrophages, Peritoneal/immunology
- Macrophages, Peritoneal/virology
- Maternal-Fetal Exchange/immunology
- Mice
- Mice, Inbred ICR
- Pregnancy
- Pregnancy Complications, Infectious/immunology
- Pregnancy Complications, Infectious/virology
- Viremia/immunology
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Affiliation(s)
- N L Zitterkopf
- Department of Basic Biomedical Sciences, University of South Dakota School of Medicine, 414 E. Clark St., Vermillion, SD 57069, USA
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21
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Mahieu-Caputo D, Senat MV, Romana S, Houfflin-Debarge V, Gosset P, Audibert F, Bessis R, Ville Y, Vekemans M, Dommergues M. [What's new in fetal medicine?]. Arch Pediatr 2002; 9:172-86. [PMID: 11915501 DOI: 10.1016/s0929-693x(01)00728-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
One of the major progress in fetal medicine in recent years is the increased sensitivity of sonographic screening for foetal malformations, due to technical improvement but also to a better training of professionals. Screening for chromosomal abnormalities is no longer based on maternal age alone. Second trimester maternal serum screening (MSS) is increasingly used: thus in 1997, 376,798 MSS tests were performed in France, yielding to the prenatal diagnosis of 391 cases of Down's syndrome. First trimester sonographic nuchal translucency measurement (NTM) is an effective screening method when performed under stringent conditions. Quality control however, is more difficult to implement on a large scale for NTM than for MSS. Performing screening tests sequentially carries a danger of generating an unnecessarily high number of amniocentesis, which may be obviated by a rational calculation of an individual's risk to carry an aneuploid baby. First trimester MSS is expected to become standard practice in the next years, probably in combination with NTM. Cytogenetics underwent substantial innovations recently, due to the ever-increasing use of molecular cytogenetics. FISH techniques allow: 1) precise analysis of unexpected structural chromosomal abnormalities diagnosed by routine amniocentesis, 2) rapid screening of the most common aneuploidies by amniocentesis when a fetal structural anomaly is detected by 3rd trimester ultrasound, 3) diagnosis of micro-deletions suspected by fetal ultrasound or post-mortem. Prenatal diagnosis by maternal blood sampling and fetal cells or DNA analysis is now part of routine clinical practice in selected cases, such as fetal sexing in families affected by an X linked disease. Thus one can select those pregnancies eligible to invasive prenatal diagnosis. Pre implantation diagnosis, which has not been legal in France until 1999 is now increasingly used as an alternative to first trimester diagnosis. As for fetal therapy, a major recent breakthrough is the prenatal management of twin to twin transfusion syndrome by either amnioreduction or laser coagulation of inter-twin vascular shunts. In addition, new pathophysiologic concepts involving the renin angiotestin system could lead to further therapeutic innovations. A European randomised trial is now being completed to establish the respective indications of drainage and Laser. All this underscores that fetal medicine is no longer solely a succession of dramatic technical breakthroughs, but is entered an era of large-scale diffusion that requires evidence based evaluation.
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Affiliation(s)
- D Mahieu-Caputo
- Service de gynécologie-obstétrique, hôpital Bichat, Paris, France
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22
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Fukushima A, Utsugisawa Y, Wada Y, Mizusawa N, Horiuchi S, Kagabu T. The application of magnetic cell sorter (MACS) to detect fetal cells in maternal peripheral blood. J Obstet Gynaecol Res 2001; 27:155-62. [PMID: 11561832 DOI: 10.1111/j.1447-0756.2001.tb01240.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES The aim of the present study was to investigate the effectiveness of sorting fetal nucleated red blood cells (FNRBC) from maternal peripheral blood, particularly during early gestation periods, by a combination of specific gravity centrifugation and magnetic cell sorter (MACS). METHODS Without prior knowledge of the gender of the fetus, we determined gender by analyzing a Y-chromosome specific sequence by nested-PCR, using 10 ml of the peripheral blood of healthy primigravida women at different stages of gestation (first trimester: n = 17, second trimester: n = 13, and third trimester: n = 19). The results of this prenatal sex determination were compared to the sex of newborns. RESULTS The specificity, sensitivity, positive predictive value (PPV) and negative predictive value (NPV) of the present method during the first trimester were 100, 81.8, 100, and 75%, respectively; during the second trimester, 80, 50, 80, and 50%, respectively; and during the third trimester, 25, 63.6, 53.8, and 33.3%, respectively. CONCLUSION The results show that this prenatal sex determination method has a highly accurate diagnostic rate during the first trimester, suggesting that it could be developed as a practical, non-invasive prenatal diagnostic technique for use during early gestation periods.
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Affiliation(s)
- A Fukushima
- Department of Obstetrics and Gynecology, School of Medicine, Iwate Medical University, Morioka, Japan
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23
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Abstract
Not every aspect of sonographic examination reveals karyotypic abnormalities. Ultrasound examination of a fetus with trisomy 21 generally reveals normal amniotic fluid, normal placentation, and normal fetal growth. In addition, other chromosomal abnormalities have many of the same sonographic findings as Down syndrome, and many findings have a large overlap with phenotypically normal fetuses. The importance of second-trimester ultrasound screening for Down syndrome has remained great because of its ease of use and relative effectiveness. Trained sonographers can adjust the relative risk for trisomy 21 and alter the need for genetic amniocentesis. It is important that parents understand the limitations of a screening test and the risks and benefits of possible subsequent confirmatory testing. If a major structural abnormality is identified on ultrasound, karyotype determination should be considered. Nuchal thickness in the first or second trimester remains the most clinically useful marker for trisomy 21. The predictive value of all the markers depends on the population studied and can be modified by a host of biochemical markers and historical factors. If fetal karyotype analysis could be performed without sampling through the uterus, prenatal diagnosis could be offered to all pregnant women, and screening would be unnecessary. Despite its limitations, ultrasound will have an important role in prenatal diagnosis at least until isolating and testing fetal cells from maternal blood or other sources becomes practical and widely available. Whether used alone or in conjunction with additional biochemical or molecular serum markers, ultrasound is an important and powerful tool in prenatal genetic evaluation.
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Affiliation(s)
- M H Graupe
- Department of Obstetrics and Gynecology, Cedars-Sinai Medical Center, UCLA School of Medicine, Los Angeles, California, USA
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24
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Siffroi JP, Freiss-Rouas N, Kanafani S, Menier C. [Fetal cells in the maternal blood and prenatal diagnosis]. GYNECOLOGIE, OBSTETRIQUE & FERTILITE 2000; 28:785-91. [PMID: 11127030 DOI: 10.1016/s1297-9589(00)00018-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Fetal loss after amniocentesis or chorionic villus sampling is a limit to prenatal diagnosis practice and to its generalization. The existence of fetal cells in the blood of pregnant women is now well established. Recognizing these cells with specific antibodies and isolating them with fluorescent or magnetic systems are the subject of numerous studies. However, to date, neither the sensitivity nor the specificity of these methods are sufficient to allow a non invasive prenatal diagnosis.
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Affiliation(s)
- J P Siffroi
- Service d'histologie, biologie de la reproduction et cytogénétique, hôpital Tenon, 4, rue de la Chine, 75020 Paris, France.
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25
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Abstract
BACKGROUND/AIMS Recent studies have suggested a role of fetal microchimerism in the pathogenesis of scleroderma. The present study investigated the potential role of fetal microchimerism in primary biliary cirrhosis (PBC), a closely related disease. METHODS A quantitative nested polymerase chain reaction was used to detect Y-chromosome sequences in the peripheral blood or the liver of PBC women and controls having male children and no transfusion or miscarriage history. RESULTS Male microchimerism was found in the peripheral blood from 45% (9 of 20) of PBC women and 25% (5 of 20) of healthy controls matched for the number of male children and age of the youngest son (p=0.28), and in the liver-biopsy specimens from 33% (5 of 15) of PBC women and 32% (8 of 25) of controls. The level of chimerism did not differ between patients and controls either in blood or in liver. Microchimerism was not related to the severity of the disease but was more frequent in PBC patients with anticentromere antibodies (p=0.049). CONCLUSIONS Fetal microchimerism does not seem to play a major role in most cases of PBC. However, the association with anticentromere antibodies suggests a possible role in the subgroup of patients with CREST syndrome or scleroderma.
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Affiliation(s)
- C Corpechot
- Service d'Hepato-Gastro-Entérologie, Hôpital Saint-Antoine, Paris, France.
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26
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Daryani YP, Barker GH, Penna LK, Patton MA. Transcervical sampling as a means of detection of fetal cells during the first trimester of pregnancy. Am J Obstet Gynecol 2000; 183:752-4. [PMID: 10992204 DOI: 10.1067/mob.2000.106819] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Our aim was to evaluate the detection of fetal cells from transcervical samples by means of fluorescence in situ hybridization analysis. STUDY DESIGN Forty-seven women undergoing first-trimester termination of pregnancy were recruited for transcervical sampling and 16 were recruited for endocervical mucus aspiration. Subjects were asked to assess the discomfort of the procedure. Fluorescence in situ hybridization analyses were performed with X and Y chromosome-specific probes. Results were compared with those of conventional chromosomal analysis. RESULTS Male signals (XY) were observed in 19 of 25 male fetuses (76%), and female signals (XX) were observed in 21 of 22 female fetuses. There was a significant variation between operators in cell retrieval. With mucus aspiration only 37.5% of male fetuses were correctly identified. The subjects did not find the procedure uncomfortable and reported that it was comparable to having a cervical smear taken. CONCLUSIONS Transcervical irrigation correctly identified the sex of 76% of male fetuses, but it still has considerable operator variability. This variability might be reduced by improved catheter design.
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Affiliation(s)
- Y P Daryani
- Department of Medical Genetics and the Department of Obstetrics and Gynaecology, St George's Hospital Medical School. London, United, Kingdom
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27
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Rodr�guez de Alba M, Gonz�lez-Gonz�lez MC, Palomino P, Ramos C. Prenatal diagnosis on fetal cells from maternal peripheral blood in cases of confined placental mosaicism. Prenat Diagn 2000. [DOI: 10.1002/(sici)1097-0223(200003)20:3<264::aid-pd780>3.0.co;2-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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28
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Rodríguez De Alba M, Palomino P, Jurado A, Sanz R, Ibañez MA, Fernández-Moya JM, Ayuso C, Díaz-Recasens J, Lahoz C, Ramos C. Prenatal diagnosis on fetal cells obtained from maternal peripheral blood: report of 66 cases. Prenat Diagn 1999; 19:934-40. [PMID: 10521819 DOI: 10.1002/(sici)1097-0223(199910)19:10<934::aid-pd675>3.0.co;2-p] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The potential use of fetal cells circulating in maternal blood for a non-invasive prenatal diagnosis has been widely described. Several authors have developed different methods for the enrichment of fetal cells from maternal peripheral blood. The aim of this study was to make a practical valuation of this new prenatal diagnosis technique, using those methods described as efficient and easy to carry out in a prenatal diagnosis unit. These methods consist of the double-density gradient and the positive selection by magnetic activated cell sorting (MACS) of the fetal erythroblasts, and the posterior study of the cells applying the FISH interphasic technique. Once the technique was ready, we obtained results from the study of 66 venous blood samples from women coming for prenatal diagnosis. Using a specific staining for fetal haemoglobin, fetal cells were identified in 63 cases. Fetal sex was well determined in 56 cases, 23 females and 33 males; in 7 cases the sex determination failed. All the aneuploidies found in a previous prenatal diagnosis were confirmed.
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29
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Hahn S, Garvin AM, Di Naro E, Holzgreve W. Allele drop-out can occur in alleles differing by a single nucleotide and is not alleviated by preamplification or minor template increments. GENETIC TESTING 1999; 2:351-5. [PMID: 10464616 DOI: 10.1089/gte.1998.2.351] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The ability to analyze the genetic material of single cells by the PCR opens up new prospects for diagnostics. Because only two copies of the genetic template are available for amplification, a problem that frequently arises when examining heterozygous loci in single cells is allele drop-out (ADO). ADO results from the preferential amplification of one of a pair of heterozygous alleles, in which the other allele is totally under-represented. In examining single cells from carriers heterozygous for beta-thalassemia mutations, we have found ADO to occur in alleles differing by a single nucleotide, where either the normal or the mutant genotype was absent. We have found that ADO is not overcome by either increasing the amount of DNA template to 20 pg or by primer extension preamplification (PEP), but rather that the best diagnostic accuracy is obtained by examining multiple single cells and basing a diagnosis on the combined results of such an examination.
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Affiliation(s)
- S Hahn
- Department of Obstetrics and Gynecology, University of Basel, Switzerland.
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30
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Miller D, Briggs J, Rahman MS, Griffith-Jones M, Rane V, Everett M, Lilford RJ, Bulmer JN. Transcervical recovery of fetal cells from the lower uterine pole: reliability of recovery and histological/immunocytochemical analysis of recovered cell populations. Hum Reprod 1999; 14:521-31. [PMID: 10100004 DOI: 10.1093/humrep/14.2.521] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The aim of this work was to isolate, enumerate and attempt the identification of fetal cells recovered from the lower uterine pole. Immediately before elective termination of pregnancy at 7-17 weeks gestation, samples were recovered by transcervical flushing of the lower uterine pole (n = 108) or transcervical aspiration of mucus from just above the internal os (n = 187), and their contents examined using histological, immunohistochemical and molecular techniques. Syncytiotrophoblasts were identified morphologically in 28 out of 89 (31%) and 50 out of 180 (28%) flushings and aspirates respectively (mean 29%). Immunocytochemistry with monoclonal antibodies (mAbs) recognizing trophoblast or epithelial cell antigens on a smaller number of samples (n = 69) identified putative placental cells in 13 out of 19 (68%) and 25 out of 50 (50%) flushings and aspirates respectively (mean 55%). These included groups of distinctive cells with a small, round, hyperchromatic nucleus, strongly reactive with mAbs PLAP, NDOG1 and FT1.41.1. Smaller groups of larger, amorphous cells, usually containing multiple large, pale staining nuclei, reactive with mAb 340 and to a lesser degree with mAb NDOG5 were also observed. Taking cellular morphology and immunophenotype into consideration, the smaller uninucleate cells were likely to be villous mesenchymal cells, while the larger cells were possibly degrading villous syncytiotrophoblast. There was no significant difference in the frequency of fetal cells obtained by the two recovery methods. Squamous or columnar epithelial cells, labelled strongly with antibodies to cytokeratins or human milk fat globule protein, were observed in 97% (29 out of 30) of aspirates. The use of cervagem in a small number of patients prior to termination of pregnancy did not appear to influence the subsequent recovery of placental cells. Y-specific DNA was detected by polymerase chain reaction (PCR) in 13 out of 26 (50%) flushings and (99 out of 154) 64% aspirates analysed (mean 62%). In-situ hybridization (ISH) revealed Y-specific targets in 40 out of 69 (60%) of aspirates analysed. A comparison of PCR data obtained from transcervical recovered samples and placental tissues showed a concordance of 80% (76 out of 95), with 10 false positives. Comparing the PCR data from tissues with data derived by ISH from 41 aspirates gave a concordance of 90% with two false positives. Although syncytiotrophoblasts were much more likely to be present in samples containing immunoreactive placental cells, the detection rates of fetal-derived DNA were similar regardless of the morphological and/or immunological presence of placental cells. We conclude that the transcervical recovery of fetal cells, while promising, requires considerable additional effort being expended in further research and development, particular in the sampling procedure.
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Affiliation(s)
- D Miller
- Centre for Reproduction, Growth and Development, University of Leeds, UK
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31
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Oosterwijk JC, Knepflé CF, Mesker WE, Vrolijk H, Sloos WC, Pattenier H, Ravkin I, van Ommen GJ, Kanhai HH, Tanke HJ. Strategies for rare-event detection: an approach for automated fetal cell detection in maternal blood. Am J Hum Genet 1998; 63:1783-92. [PMID: 9837832 PMCID: PMC1377651 DOI: 10.1086/302140] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
This article explores the feasibility of the use of automated microscopy and image analysis to detect the presence of rare fetal nucleated red blood cells (NRBCs) circulating in maternal blood. The rationales for enrichment and for automated image analysis for "rare-event" detection are reviewed. We also describe the application of automated image analysis to 42 maternal blood samples, using a protocol consisting of one-step enrichment followed by immunocytochemical staining for fetal hemoglobin (HbF) and FISH for X- and Y-chromosomal sequences. Automated image analysis consisted of multimode microscopy and subsequent visual evaluation of image memories containing the selected objects. The FISH results were compared with the results of conventional karyotyping of the chorionic villi. By use of manual screening, 43% of the slides were found to be positive (>=1 NRBC), with a mean number of 11 NRBCs (range 1-40). By automated microscopy, 52% were positive, with on average 17 NRBCs (range 1-111). There was a good correlation between both manual and automated screening, but the NRBC yield from automated image analysis was found to be superior to that from manual screening (P=.0443), particularly when the NRBC count was >15. Seven (64%) of 11 XY fetuses were correctly diagnosed by FISH analysis of automatically detected cells, and all discrepancies were restricted to the lower cell-count range. We believe that automated microscopy and image analysis reduce the screening workload, are more sensitive than manual evaluation, and can be used to detect rare HbF-containing NRBCs in maternal blood.
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Affiliation(s)
- J C Oosterwijk
- Department of Cytochemistry, Leiden University Medical Center, The Netherlands.
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32
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Oosterwijk JC, Mesker WE, Ouwerkerk-Van Velzen MCM, Knepflé CFHM, Wiesmeijer KC, Beverstock GC, Van Ommen GJB, Tanke HJ, Kanhai HHH. Prenatal diagnosis of trisomy 13 on fetal cells obtained from maternal blood after minor enrichment. Prenat Diagn 1998. [DOI: 10.1002/(sici)1097-0223(1998100)18:10<1082::aid-pd383>3.0.co;2-d] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Nelson JL, Furst DE, Maloney S, Gooley T, Evans PC, Smith A, Bean MA, Ober C, Bianchi DW. Microchimerism and HLA-compatible relationships of pregnancy in scleroderma. Lancet 1998; 351:559-62. [PMID: 9492775 DOI: 10.1016/s0140-6736(97)08357-8] [Citation(s) in RCA: 451] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Fetal cells can be found in the maternal circulation in most pregnancies. Fetal progenitor cells have been found to persist in the circulation of women many years after childbirth. We tested the hypothesis that microchimerism is involved in the pathogenesis of scleroderma. Scleroderma is of interest because of a strong female predilection, an increased incidence in the years after childbearing, and clinical similarities between scleroderma and chronic graft-versus-host disease after allogeneic bone-marrow transplantation. We also investigated whether HLA-compatibility of a child was associated with later development of scleroderma in the mother. METHODS We enrolled 40 women who had previously given birth to at least one son--16 healthy controls, 17 scleroderma patients, and seven healthy sisters of patients. We used quantitative PCR to amplify a Y-chromosome-specific sequence in whole peripheral blood from these women. Also 32 controls with 58 children, and 21 scleroderma patients with 47 children were HLA genotyped. FINDINGS The mean number of male cell DNA equivalents among controls was 0.38 cells per 16 mL whole blood (median 0 [range 0-2]) and 11.1 (6.0 [0-61]) among scleroderma patients (p = 0.0007). Controls' youngest sons were born a mean of 15.4 years previously, and scleroderma patients' sons 18.5 years previously. Some scleroderma patients had concentrations of male DNA higher than those found in most pregnant women. HLA-class II compatibility of a child from the mother's perspective was more common among scleroderma patients than among controls, but was not essential for persistence of male DNA in maternal peripheral blood. INTERPRETATION Low concentrations of male DNA can be detected in healthy women decades after the birth of a son. Microchimerism in scleroderma patients could be secondary to the underlying disease. However, the finding that HLA class II compatibility of a child was more common for scleroderma patients than for controls, supports the possibility that microchimerism may be involved in the pathogenesis of scleroderma.
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Affiliation(s)
- J L Nelson
- Fred Hutchinson Cancer Research Center, Seattle, Washington 98104-2092, USA
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34
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van Wijk IJ, van Vugt JM, Könst AA, Mulders MA, Florijn WJ, Oudejans CB. Identification of hash2-positive extravillus trophoblast cells in the peripheral blood of pregnant women. Placenta 1998. [DOI: 10.1016/s0143-4004(98)80004-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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35
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36
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Bianchi DW, Williams JM, Sullivan LM, Hanson FW, Klinger KW, Shuber AP. PCR quantitation of fetal cells in maternal blood in normal and aneuploid pregnancies. Am J Hum Genet 1997; 61:822-9. [PMID: 9382092 PMCID: PMC1715976 DOI: 10.1086/514885] [Citation(s) in RCA: 283] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Fetal cells in maternal blood are a noninvasive source of fetal genetic material for prenatal diagnosis. We determined the number of fetal-cell DNA equivalents present in maternal whole-blood samples to deduce whether this number is affected by fetal karyotype. Peripheral blood samples were obtained from 199 women carrying chromosomally normal fetuses and from 31 women with male aneuploid fetuses. Male fetal-cell DNA-equivalent quantitation was determined by PCR amplification of a Y chromosome-specific sequence and was compared with PCR product amplified from known concentrations of male DNA run simultaneously. The mean number of male fetal-cell DNA equivalents detected in 16-ml blood samples from 90 women bearing a 46,XY fetus was 19 (range 0-91). The mean number of male fetal-cell DNA equivalents detected in 109 women bearing a 46,XX fetus was 2 (range 0-24). The mean number of male fetal-cell DNA equivalents detected when the fetus was male compared with when the fetus was female was highly significant (P = .0001). More fetal cells were detected in maternal blood when the fetus was aneuploid. The mean number of male fetal-cell DNA equivalents detected when the fetal karyotype was 47,XY,+21 was 110 (range 0.1-650), which was significantly higher than the number of male fetal-cell DNA equivalents detected in 46,XY fetuses (P = .0001). Feto-maternal transfusion of nucleated cells appears to be influenced by fetal karyotype. The sixfold elevation of fetal cells observed in maternal blood when the fetus had trisomy 21 indicates that noninvasive cytogenetic diagnosis of trisomy 21 should be feasible.
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Affiliation(s)
- D W Bianchi
- Department of Pediatrics, New England Medical Center and Tufts University School of Medicine, Boston, MA 02111, USA.
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Frequency of Fetal Cells in Sorted Subpopulations of Nucleated Erythroid and CD34+ Hematopoietic Progenitor Cells From Maternal Peripheral Blood. Blood 1997. [DOI: 10.1182/blood.v89.7.2347] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Fetal cells that circulate in maternal peripheral blood (PB) during pregnancy offer a potential source of nucleated fetal material for noninvasive prenatal diagnosis. Fluorescence-activated cell sorting was used to target two populations of fetal cells: nucleated erythroid cells (NECs; CD71/glycophorin-A+ CD45lo-int CD34−) and hematopoietic progenitor cells (CD34+ cells; CD34++ CD71/glycophorin-A− CD45int). Fetal cells were detected by fluorescence in situ hybridization (FISH) using directly conjugated chromosome X and Y probes in 65% (13 of 20) of the maternal PBs (fetal karyotype 46,XY). The frequency of fetal cells isolated from the NEC and CD34+ fractions was, respectively, 0 to 14 and 0 to 7 cells per 2 × 107 previously frozen maternal cells (≈20 mL of blood). In nonfrozen samples, the yield and recovery of fetal cells was moderately improved. Culturing the CD34+ sorted fractions in serum-free media with cytokines improved the quality of the FISH preparations and resulted in a slight expansion in detectable fetal cells. The frequency of fetal cells isolated from cultured CD34+ fractions was 0 to 35 and 0 to 93 cells per 2 × 107 previously frozen and nonfrozen maternal PB cells, respectively. These results document the isolation, characterization, and enumeration of fetal cells from the maternal periphery that appear to be present in most, but not all, samples analyzed.
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38
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Abstract
Twenty-one women (age range 17-38 years) undergoing termination for social reasons in the first trimester were selected. Ultrasound determined the gestation and placental site. A commercially available flexible, sterile plastic tube was advanced to the level of the internal os. Five to eight millilitres of normal saline was injected and then gently aspirated into the tube. Chorionic villus sampling (CVS) or amniocentesis was subsequently performed for back-up sexing. Commercial X and Y probes were used simultaneously for fluorescence in situ hybridization (FISH) study of the cervical washing and back-up samples, XY signals were observed in 10 out of 12 male fetuses and 1 out of 4 female fetuses (false positive), indicating 81.3 per cent correct prediction. Four cervical washing samples did not provide enough cells for FISH. The frequency of cells showing XY signals varied from 3.6 to 47.8 per cent in male-predicted pregnancies. Placental-location, gestational age, or maternal age did not affect the successful retrieval of fetal cells. Trophoblast cells were obtained in a significant number (83 per cent) of pregnant women with male pregnancies by transcervical irrigation in the first trimester. This preliminary part of the study shows the presence of fetal cells in the transcervical samplings and the feasibility of FISH in detecting them; however, further studies are needed to isolate and purify fetal cells.
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Affiliation(s)
- Y P Daryani
- Department of Medical Genetics, St George's Hospital Medical School, London, U.K
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39
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Abstract
Laboratory advances in molecular genetics have resulted in numerous clinical applications for DNA analysis. Currently, because of cost, complexity, and resource limitations, DNA analysis is not used routinely for prenatal screening, but rather is targeted towards families at risk for an inherited condition. This article discusses the types of DNA analyses that are currently performed, the possible tissue sources of DNA for prenatal diagnosis, and the indications for DNA testing in obstetric practice. Internet addresses for the most up-to-date genetic information on a specific condition are given in this article.
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Affiliation(s)
- G K Gupta
- Department of Pediatrics, Tufts University School of Medicine, Boston, Massachusetts, USA
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40
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Abstract
Major adaptations in maternal physiology and metabolism are required for successful pregnancy outcome. Hormonal changes initiated even before conception significantly alter maternal biochemistry early in pregnancy. Steroid hormones, peptide hormones, and prostaglandins interact to expand blood and plasma volume and modulate the maternal capacity to supply energy and nutrients to the fetoplacental unit. As gestation progresses, reference ranges for the concentration of many biochemical parameters change significantly from those found in the nonpregnant state. Gestation-specific reference ranges are essential for correct interpretation of tests used in screening, diagnosis, and monitoring during pregnancy. The use of clinical laboratory tests in the management of high-risk pregnancy are discussed from the perspective of testing before conception and during pregnancy.
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Affiliation(s)
- G Lockitch
- Department of Pathology and Laboratory Medicine, University of British Columbia, Canada.
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Papadogiannakis N. Traffic of leukocytes through the maternofetal placental interface and its possible consequences. Curr Top Microbiol Immunol 1997; 222:141-57. [PMID: 9257490 DOI: 10.1007/978-3-642-60614-4_7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- N Papadogiannakis
- Karolinska Institute, Department of Pathology, Huddinge University Hospital, Sweden
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42
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Affiliation(s)
- N J Leschot
- Department of Human Genetics, Academic Medical Center, University of Amsterdam, The Netherlands
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Miller D, Briggs J. Reliability of trans-cervical recovery of placental cells from the lower uterine pole using a minimally invasive procedure. Evidence based on fetal sexing and analysis of recovered cell populations. Early Hum Dev 1996; 47 Suppl:S99-102. [PMID: 9031852 DOI: 10.1016/s0378-3782(96)01831-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Efficient recovery of placental cells (and their subsequent characterisation) from the lower uterine pole (L.U.P) by trans-cervical flushing or aspiration. SUBJECTS Women attending for termination of pregnancy (7-17 weeks' gestation) for social reasons. All patients gave their consent to the procedures outlined below. METHODS Trans-cervical intrauterine flushing (using 0.15 M NaCl) or mucus aspiration. Embryo transfer catheters were used in both procedures. Fetal sexing was achieved by gene amplification of Y-specific DNA sequences (Y-PCR), and by in situ hybridisation (bright-field and fluorescence) to the Y-chromosome. Data were compared with results obtained from fetal tissues recovered following termination of pregnancy. Gender-independent tests for fetal cells utilised immunocytochemistry with trophoblast-specific antibodies and dual immunocytochemistry/ISH, where appropriate. RESULTS (1) Fetal sexing by Y-PCR: 71/122 (58%) aspirates contained Y-specific DNA. In addition, the sexing of 72/86 (84%) aspirates and their corresponding samples of placental tissue, agreed exactly. (2) Microscopic detection of fetal cells. Placentally-derived syncytiotrophoblast was detected in 17/45 (38%) flushings and 39/173 (23%) aspirates. In most other Y-PCR+ samples which were negative for syncytiotrophoblast, Y-chromosome-bearing nuclei of unknown origin, were observed by ISH and immunocytochemical evidence for cytotrophoblastic cells was also uncovered. CONCLUSIONS Since Y-derived DNA can be detected in > 50% of flushings and aspirations, and gender-independent evidence for placental cells was obtained, regardless of fetal sex, we believe that most or all of these samples contained placental cells, including trophoblasts and naked nuclei. Trans-cervical placental cell recovery is a potentially valuable alternative to more invasive methods of aneuploid detection which require amniocentesis and CVS, provided its level of accuracy and above all, safety, can be evaluated.
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Affiliation(s)
- D Miller
- Division of Obstetrics and Gynaecology, University of Leeds, Leeds General Infirmary, UK
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44
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Cheung MC, Goldberg JD, Kan YW. Prenatal diagnosis of sickle cell anaemia and thalassaemia by analysis of fetal cells in maternal blood. Nat Genet 1996; 14:264-8. [PMID: 8896554 DOI: 10.1038/ng1196-264] [Citation(s) in RCA: 203] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Currently, amniocentesis, chorionic villus sampling (CVS) and fetal blood sampling are used to obtain fetal cells for genetic diagnosis. These invasive procedures pose a small but not negligible risk for the fetus. Efforts have been directed towards the enrichment of fetal cells, such as erythroblasts, from maternal blood and progress has been made in the diagnosis of some chromosomal disorders and in sex determinations. We now report the detection of point mutations in single gene disorders using this method of prenatal diagnosis by enriching fetal cells from maternal blood by magnetic cell sorting followed by isolation of pure fetal cells by microdissection. In two pregnancies at risk for sickle cell anaemia and beta-thalassaemia, we successfully identified the fetal genotypes. Thus, prenatal diagnosis of single gene disorders by recovering fetal cells from maternal circulation appears to be a feasible approach.
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Affiliation(s)
- M C Cheung
- Howard Hughes Medical Institute, University of California, San Francisco 94143-0724, USA
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45
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46
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Lees MM, Winter RM. Advances in genetics. Arch Dis Child 1996; 75:346-50. [PMID: 8984927 PMCID: PMC1511743 DOI: 10.1136/adc.75.4.346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- M M Lees
- Mothercare Unit of Clinical Genetics and Fetal Medicine, Institute of Child Health, London
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