The Banks of the Indus.

I remember the banks of the IndusThe silt and the paternal loveCarefree runs, clear minds under the basking sunIt feels to be the time when I truly livedAway from the realities, far from the worldly touchA place all to me where I thrived.

mRNA and Protein Expression in Human Fetal Membrane Cells: Potential Biomarkers for Preterm Prelabor Rupture of the Fetal Membranes?

Clinically, unique markers in fetal membrane cells may contribute to the search for biomarkers for preterm prelabor rupture of the fetal membranes (pPROM) in maternal blood. pPROM is associated with overwhelming inflammation and premature cellular senescence causing "biological microfractures" of the fetal membranes. We hypothesize that these pathological processes are associated with the shedding of fetal membrane cells into the maternal circulation. The aim of this study was to identify markers expressed exclusively in fetal membrane cells to facilitate their isolation, characterization, and determination of biomarker potential in maternal blood. We have (1), by their transcriptomic profile, identified markers that are upregulated in amnion and chorion tissue compared to maternal white blood cells, and (2), by immunohistochemistry, confirmed the localization of the differentially expressed proteins in fetal membranes, placenta, and the placental bed of the uterus. RNA sequencing revealed 31 transcripts in the amnion and 42 transcripts in the chorion that were upregulated. Among these, 22 proteins were evaluated by immunohistochemistry. All but two transcripts were expressed both on mRNA and protein level in at least one fetal membrane cell type. Among these remaining 20 proteins, 9 proteins were not significantly expressed in the villous and extravillous trophoblasts of the placenta.

Clinical interpretation of cell-based non-invasive prenatal testing for monogenic disorders including repeat expansion disorders: potentials and pitfalls.

Introduction: Circulating fetal cells isolated from maternal blood can be used for prenatal testing, representing a safe alternative to invasive testing. The present study investigated the potential of cell-based noninvasive prenatal testing (NIPT) for diagnosing monogenic disorders dependent on the mode of inheritance. Methods: Maternal blood samples were collected from women opting for prenatal diagnostics for specific monogenic disorders (N = 7). Fetal trophoblasts were enriched and stained using magnetic activated cell sorting and isolated by fluorescens activated single-cell sorting. Individual cells were subject to whole genome amplification, and cells of fetal origin were identified by DNA-profiling using short tandem repeat markers. The amplified fetal DNA was input for genetic testing for autosomal dominant-, autosomal recessive-, X-linked and repeat expansion disorders by direct variant analysis and haplotyping. The cell-based NIPT results were compared with those of invasive testing. Results: In two cases at risk of skeletal dysplasia, caused by variants in the FGFR3 gene (autosomal dominant disorders), cell-based NIPT correctly stated an affected fetus, but allelic dropout of the normal alleles were observed in both cases. Cell-based NIPT gave an accurate result in two cases at risk of autosomal recessive disorders, where the parents carried either different diastrophic dysplasia causing variants in the SLC26A2 gene or the same cystic fibrosis disease-causing variant in the CFTR gene. Cell-based NIPT accurately identified an affected male fetus in a pregnancy at risk of Duchenne muscular dystrophy (DMD gene, X-linked recessive disorders). In two cases at risk of the myotonic dystrophy type 1 (DMPK gene, repeat expansion disorder), cell-based NIPT correctly detected an affected and an unaffected fetus, respectively. Discussion: Circulating fetal cells can be used to detect both maternally- and paternally inherited monogenic disorders irrespective of the type of variant, however, the risk of allelic dropout must be considered. We conclude that the clinical interpretation of the cell-based NIPT result thus varies depending on the disorders' mode of inheritance.

How does cell-based non-invasive prenatal test (NIPT) perform against chorionic villus sampling and cell-free NIPT in detecting trisomies and copy number variations? A clinical study from Denmark.

OBJECTIVES: We aimed to compare cell-based NIPT (cbNIPT) to chorionic villus sampling (CVS) and to examine the test characteristics of cbNIPT in the first clinical validation study of cbNIPT compared to cell-free NIPT (cfNIPT). MATERIAL AND METHODS: Study 1: Women (N = 92) who accepted CVS were recruited for cbNIPT (53 normal and 39 abnormal). Samples were analyzed with chromosomal microarray (CMA). Study 2: Women (N = 282) who accepted cfNIPT were recruited for cbNIPT. cfNIPT was analyzed using sequencing and cbNIPT by CMA. RESULTS: Study 1: cbNIPT detected all aberrations (32/32) found in CVS: trisomies 13, 18 and 21 (23/23), pathogenic copy number variations (CNVs) (6/6) and sex chromosome aberrations (3/3). cbNIPT detected 3/8 cases of mosaicism in the placenta. Study 2: cbNIPT detected all trisomies found with cfNIPT (6/6) and had no false positive (0/246). One of the three CNVs called by cbNIPT was confirmed by CVS but was undetected by cfNIPT, two were false positives. cbNIPT detected mosaicism in five samples, of which two were not detected by cfNIPT. cbNIPT failed in 7.8% compared to 2.8% in cfNIPT. CONCLUSION: Circulating trophoblasts in the maternal circulation provide the potential of screening for aneuploidies and pathogenic CNVs covering the entire fetal genome.

Diagnosis of hydatidiform moles using circulating gestational trophoblasts isolated from maternal blood.

INTRODUCTION: Identifying hydatidiform moles (HMs) is crucial due to the risk of gestational trophoblastic neoplasia. When a HM is suspected on clinical findings, surgical termination is recommended. However, in a substantial fraction of the cases, the conceptus is actually a non-molar miscarriage. If distinction between molar and non-molar gestations could be obtained before termination, surgical intervention could be minimized. METHODS: Circulating gestational trophoblasts (cGTs) were isolated from blood from 15 consecutive women suspected of molar pregnancies in gestational week 6-13. The trophoblasts were individually sorted using fluorescence activated cell sorting. STR analysis targeting 24 loci was performed on DNA isolated from maternal and paternal leukocytes, chorionic villi, cGTs, and cfDNA. RESULTS: With a gestational age above 10 weeks, cGTs were isolated in 87% of the cases. Two androgenetic HMs, three triploid diandric HMs, and six conceptuses with diploid biparental genome were diagnosed using cGTs. The STR profiles in cGTs were identical to the profiles in DNA from chorionic villi. Eight of the 15 women suspected to have a HM prior to termination had a conceptus with a diploid biparental genome, and thus most likely a non-molar miscarriage. DISCUSSION: Genetic analysis of cGTs is superior to identify HMs, compared to analysis of cfDNA, as it is not hampered by the presence of maternal DNA. cGTs provide information about the full genome in single cells, facilitating estimation of ploidy. This may be a step towards differentiating HMs from non-HMs before termination.

Noninvasive prenatal screening for cystic fibrosis using circulating trophoblasts: Detection of the 50 most common disease-causing variants.

OBJECTIVES: Cystic fibrosis (CF) is one of the most common severe autosomal recessive disorders. Prenatal or preconception CF screening is offered in some countries. A maternal blood sample in early pregnancy can provide circulating trophoblasts and offers a DNA source for genetic analysis of both the mother and the fetus. This study aimed to develop a cell-based noninvasive prenatal test (NIPT) to screen for the 50 most common CF variants. METHODS: Blood samples were collected from 30 pregnancies undergoing invasive diagnostics and circulating trophoblasts were harvested in 27. Cystic fibrosis testing was conducted using two different methods: by fragment length analysis and by our newly developed NGS-based CF analysis. RESULTS: In all 27 cases, cell-based NIPT provided a result using both methods in agreement with the invasive test result. CONCLUSION: This study shows that cell-based NIPT for CF screening provides a reliable result without the need for partner- and proband samples.

Cell-Based NIPT Detects 47,XXY Genotype in a Twin Pregnancy.

Background: The existing risk of procedure-related miscarriage following invasive sampling for prenatal diagnosis is higher for twin pregnancies and some women are reluctant to test these typically difficultly obtained pregnancies invasively. Therefore, there is a need for noninvasive testing options that can test twin pregnancies at an early gestational age and ideally test the twins individually. Case presentation: A pregnant woman opted for cell-based NIPT at GA 10 + 5. As cell-based NIPT is not established for use in twins, the test was provided in a research setting only, when an ultrasound scan showed that she carried dichorionic twins. Materials and Methods: Fifty mL of peripheral blood was sampled, and circulating fetal cells were enriched and isolated. Individual cells were subject to whole-genome amplification and STR analysis. Three fetal cells were analyzed by chromosomal microarray (aCGH). Results: We identified 20 fetal cells all sharing the same genetic profile, which increased the likelihood of monozygotic twins. aCGH of three fetal cells showed the presence of two X chromosomes and a gain of chromosome Y. CVS from both placentae confirmed the sex chromosomal anomaly, 47,XXY and that both fetuses were affected. Conclusion: NIPT options can provide valuable genetic information to twin pregnancies that help the couples in their decision-making on prenatal testing. Little has been published about the use of cell-based NIPT in twin pregnancies, but the method may offer the possibility to obtain individual cell-based NIPT results in dizygotic twins.

Doomsurfing and doomscrolling mediate psychological distress in COVID-19 lockdown: Implications for awareness of cognitive biases.

The coronavirus disease 2019 (COVID-19) pandemic has led to a significant increase in the consumption of the internet for work, leisure time activities, and has also generated substantial amounts of anxiety, and uncertainty, which has lead individuals to spend a lot of time surfing the internet for the latest news on developments in the COVID-19 crisis. This ends up as scrolling or surfing through a lot of pessimistic news items. This search for information during COVID-19 is apparently influenced by a number of cognitive biases as well as mediated by poor affect regulation skills. Thus, there is a need to address these cognitive biases and promote affect regulation strategies across health settings.

Screening for Fetal Aneuploidy and Sex Chromosomal Anomalies in a Pregnant Woman With Mosaicism for Turner Syndrome-Applications and Advantages of Cell-Based NIPT.

Background: Cell-free NIPT and cell-based NIPT are risk-free testing options using maternal blood samples to screen for fetal aneuploidies, but the methods differ. For cell-free NIPT, the fetal fraction of cell-free DNA in plasma is analyzed with a high background of maternal DNA. In contrast, for cell-based NIPT, a limited number of the rare, intact fetal cells are isolated for the genetic analysis. This case demonstrates the differences regarding testing for fetal sex-chromosomes anomalies (SCAs) between these two tests. Materials and Methods: A pregnant woman with mosaicism for Turner syndrome opted for NIPT in first trimester. For the cell-free NIPT analysis, DNA extraction, genome-wide massive parallel sequencing, and data analysis were carried out as described by the kit manufacturer (Illumina©, San Diego, CA, USA). For cell-based NIPT, the first sample gave no result, but the woman consented to repeat cell-based NIPT. After whole genome amplification and STR analysis, fetal DNA from three individual fetal cells was subjected to chromosomal microarray (aCGH, Agilent oligoarray, 180 kb). Results: Fetal fraction was 7%, and cell-free NIPT showed 2 copies of chromosomes 13, 18, and 21 and a decreased proportion of chromosome X, suggestive of fetal Turner syndrome. In contrast, the cell-based NIPT result showed no aneuploidy and two X-chromosomes in the fetus. Conclusion: cell-based NIPT may provide a non-invasive testing option to screen for SCAs in women with mosaicism for monosomy-X in blood, where cell-free NIPT cannot discriminate whether the X-loss is maternal or fetal.

Predictors of Hospitalization for Manic Episode in Alzheimer's Dementia: Inputs From an Inpatient Case-Control Study.

Objectives The correlates of manic episodes in dementia have not been systematically studied. The primary goal of our study is to compare the sociodemographic characteristics and psychiatric comorbidities in Alzheimer's dementia (AD) inpatients with manic episodes versus without manic episodes, and to evaluate the demographic predictors and risk factors for manic episodes in AD inpatients. Methods We conducted a case-control study using the Nationwide Inpatient Sample of 34,285 AD patients (age ≥60 years). Subsequently, the cases i.e., AD inpatients with a manic episode (N = 1,035) and the controls (without a manic episode, N = 1,035), were extracted using propensity-score matching based on age. The cases did not have a past psychiatric history of bipolar disorders. We used the logistic regression model to evaluate the odds ratio (OR) of association between pre-existing psychiatric comorbidities and manic episodes and evaluate the demographic predictors of manic episodes in AD inpatients. Results A higher proportion of AD inpatients with manic episodes were females (63.8%), whites (85.2%), and from low-income families below the 50th percentile (63%). Females were more likely to be hospitalized for manic episodes (OR 1.33; 95% CI 1.09-1.64) than males. AD inpatients with manic episodes had a higher risk of presenting with suicidal behaviors (OR 1.88; 95% CI 1.23-2.86). A significantly higher proportion of AD inpatients with manic episodes had comorbid tobacco use (5.3% vs. 3.4%) and cannabis use (1.4% vs. 0%) compared to those without manic episodes. Conclusion Females with AD had a greater risk of being hospitalized for manic episodes. These patients have an 88% higher risk of suicidal behaviors during the manic presentation and have comorbid tobacco and cannabis use. Early diagnosis and management of manic episodes in at-risk AD patients are important to improve the quality of life (QoL) and outcomes.

Cyber-Physical Loops as Drivers of Value Creation in NDE 4.0.

Across so many industries, non-destructive evaluation has proven its worth time and again through quality and safety assurance of valuable assets. Yet, over time, it became underappreciated in business decisions. In most cases, the data gathered by NDT is used for quality assurance assessments resulting in binary decisions. And we seem to miss out on value of the information content of NDE which goes way deeper and can help other stakeholders: such as engineering, management, inspectors, service providers, and even regulators. Some of those groups might not even be aware of the benefits of NDE data and its digitalization. Unfortunately, the NDE industry typically makes the data access unnecessarily difficult by proprietary interfaces and data formats. Both those challenges need to be addressed now by the NDE industry. The confluence of NDE and Industry 4.0, dubbed as NDE 4.0, provides a unique opportunity for the NDE/NDT Industry to not only readjust the value perception but to gain new customer groups through a broad set of value creation activities across the ecosystem. The integration of NDE into the Cyber-Physical Loop (including IIoT and Digital Twin) is the chance for the NDE industry to now shift the perception from a cost center to a value center. This paper provides an overview of the NDE ecosystem, key value streams, cyber-physical loops that create value, and a number of use cases for various stakeholders in the ecosystem.

Cell-based non-invasive prenatal testing for monogenic disorders: confirmation of unaffected fetuses following preimplantation genetic testing.

PURPOSE: Proof of concept of the use of cell-based non-invasive prenatal testing (cbNIPT) as an alternative to chorionic villus sampling (CVS) following preimplantation genetic testing for monogenic disorders (PGT-M). METHOD: PGT-M was performed by combined testing of short tandem repeat (STR) markers and direct mutation detection, followed by transfer of an unaffected embryo. Patients who opted for follow-up of PGT-M by CVS had blood sampled, from which potential fetal extravillous throphoblast cells were isolated. The cell origin and mutational status were determined by combined testing of STR markers and direct mutation detection using the same setup as during PGT. The cbNIPT results with respect to the mutational status were compared to those of genetic testing of the CVS. RESULTS: Eight patients had blood collected between gestational weeks 10 and 13, from which 33 potential fetal cell samples were isolated. Twenty-seven out of 33 isolated cell samples were successfully tested (82%), of which 24 were of fetal origin (89%). This corresponds to a median of 2.5 successfully tested fetal cell samples per case (range 1-6). All fetal cell samples had a genetic profile identical to that of the transferred embryo confirming a pregnancy with an unaffected fetus, in accordance with the CVS results. CONCLUSION: These findings show that although measures are needed to enhance the test success rate and the number of cells identified, cbNIPT is a promising alternative to CVS. TRIAL REGISTRATION NUMBER: N-20180001.

Percutaneous catheter drainage of uncomplicated amoebic liver abscess: prospective evaluation of a clinical protocol for catheter removal and the significance of residual collections.

INTRODUCTION: Patients with amoebic liver abscess (ALA) may require percutaneous catheter drainage (PCD). Once the PCD output is substantially reduced or has ceased along with clinical recovery, residual collections on radiological evaluation may concern the treating physicians. The prevalence and significance of such collections is unknown, and the subsequent approach how to tackle them is unclear. METHODS: Consecutive patients with one or more uncomplicated ALAs requiring drainage were prospectively enrolled from 3 hospitals and managed based on a standard approach. Catheter removal was attempted after the patients fulfilled all 4 of the following criteria: disappearance of abdominal pain, absence of fever for at least 48 h, an improving trend of TLC (documented on 2 consecutive reports), and catheter drain output of < 10 ml/day for at least 2 consecutive days. RESULTS: A total of 110 patients (mean age 46.6 ± 10.5 years, 93.6% males, 89.1% alcoholics) underwent PCD placement; 69 patients (69/110; 62.7%) met all 4 criteria within 5 days of PCD placement (optimal response) and had an uncomplicated course. Patients with suboptimal responses (41/110; 37.3%) were evaluated for local and systemic complications; the appearance of fresh collections (5/110; 4.5%), abscess rupture (2/110; 1.8%), bile leakage (3/110; 2.7%), cholangitis (2/110; 1.8%), thrombophlebitis (2/110; 1.8%) and hospital-acquired infections (2/110; 1.8%) were diagnosed and treated accordingly. Ultimately, PCD removal (based on the fulfilment of all 4 criteria) was universally successful after a median of 5 days (IQR, 4-9 days). None of the patients had symptom recurrence after PCD removal, although residual collections were still seen in 97.3% of patients at the time of PCD removal and in 92.1% and 84.9% of patients available for follow-up at 1 and 3 months, respectively. CONCLUSION: Based on our clinical protocol, PCD removal in ALA can be successfully expedited even in the presence of residual collections. An inability to fulfill all 4 criteria within 5 days of PCD placement warrants further evaluations for local and systemic complications that require additional therapeutic measures.

NDE 4.0-A Design Thinking Perspective.

Cyber technologies are offering new horizons for quality control in manufacturing and safety assurance in-service of physical assets. The line between non-destructive evaluation (NDE) and Industry 4.0 is getting blurred since both are sensory data-driven domains. This multidisciplinary approach has led to the emergence of a new capability: NDE 4.0. The NDT community is coming together once again to define the purpose, chart the process, and address the adoption of emerging technologies. In this paper, the authors have taken a design thinking approach to spotlight proper objectives for research on this subject. It begins with qualitative research on twenty different perceptions of stakeholders and misconceptions around the current state of NDE. The interpretation is used to define ten value propositions or use cases under 'NDE for Industry 4.0' and 'Industry 4.0 for NDE' leading up to the clarity of purpose for NDE 4.0-enhanced safety and economic value for stakeholders. To pursue this worthy cause, the paper delves into some of the top adoption challenges, and proposes a journey of managed innovation, conscious skills development, and a new form of leadership required to succeed in the cyber-physical world.

Perception of Illness and Its Association with Treatment Willingness in Patients with Newly Diagnosed Nonalcoholic Fatty Liver Disease.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease of immense public health relevance. Understanding illness perceptions in the NAFLD population will provide sound scientific evidence for planning high-quality patient-centered care and implementing effective interventions. The Brief Illness Perception Questionnaire (BIPQ) is a robust psychometric tool to systematically assess the dimensions of illness perceptions in various chronic ailments. METHODS: In a cross-sectional study enrolling patients with newly diagnosed NAFLD, the sociodemographic, anthropometric, biochemical, and radiological determinants of enhanced illness perceptions (measured by the BIPQ score) were investigated using univariate and multivariable binary logistic regression analyses. Finally, the association between individual domains of the BIPQ and willingness to participate in comprehensive medical management was explored. RESULTS: In total, 264 patients (mean age 53 ± 11.9 years, 59.8% males) were enrolled in the final analysis. The mean and median BIPQ scores in the study population were 30.3 ± 12.8 and 31.0 (IQR, 22.0-40.0), respectively. The variables having a significant independent association with heightened perceptions (BIPQ > 31) were family history of liver disease (aOR, 5.93; 95% CI, 1.42-24.74), obesity (aOR, 3.33; 95% CI, 1.57-7.05), diabetes mellitus (aOR, 2.35; 95% CI, 1.01-5.49), and transaminitis (aOR, 2.85; 95% CI, 1.42-5.69). Patients with a higher level of illness perceptions (31.6 ± 12.9 vs 27.8 ± 12.3, p = 0.022) were more likely to express a willingness to participate in the comprehensive management plan, with 3 of the 8 domains (consequence, identity, and treatment control) mainly affecting willingness. CONCLUSION: A family history of liver disease, obesity, diabetes, and transaminitis were independently associated with increased illness perceptions. A belief in serious consequences, a strong illness identity, and higher perceived treatment control were significantly associated with the willingness to undergo comprehensive care for NAFLD.

Hydatidiform mole diagnostics using circulating gestational trophoblasts isolated from maternal blood.

BACKGROUND: In gestational trophoblastic disease, the prognosis is related to the genetic constitution. In some cases, taking a biopsy is contraindicated. METHODS: In a pregnant woman, ultrasound scanning suggested hydatidiform mole. To explore if the genetic constitution can be established without taking a biopsy (or terminating the pregnancy), cell-free DNA and circulating gestational trophoblasts were isolated from maternal blood before evacuation of the uterus. The evacuated tissue showed the morphology of a complete hydatidiform mole. Without prior whole-genome amplification, short tandem repeat analysis of 24 DNA markers was performed on the samples, and on DNA isolated from evacuated tissue, and from the blood of the patient and her partner. RESULTS: Identical genetic results were obtained in each of three circulating gestational trophoblasts and the evacuated tissue, showing that this conceptus had a diploid androgenetic nuclear genome. In contrast, analysis of cell-free DNA was less informative and less specific due to the inherent presence of cell-free DNA from the patient. CONCLUSION: Our results show that it is possible to isolate and analyze circulating gestational trophoblasts originating in a pregnancy without maternal nuclear genome. For diagnosing gestational trophoblastic diseases, genotyping circulating gestational trophoblasts appears to be superior to analysis of cell-free DNA.

Cell-based non-invasive prenatal diagnosis in a pregnancy at risk of cystic fibrosis.

OBJECTIVE: We aimed to develop cell-based NIPT for cystic fibrosis (CF) and test a pregnancy at risk of two common pathogenic variants. METHOD: A pregnant woman carrying monozygotic twins opted for prenatal testing as she and her partner were heterozygote carriers of F508del (c.1521:1523del). The partner was also positive for the CFTR-related variant R117H (c.350G>A). Fetal trophoblasts from maternal blood were enriched and isolated using antibodies and a capillary-based cell-picking instrument. Multiplex PCR-based fragment length analysis was performed on the extracted fetal DNA for STR-genotyping, fetal gender and F508del variant status. The R117H variant status was tested using SNaPshot analysis. RESULTS: The fetal origin of the isolated cells was verified by detection of two paternally inherited STR alleles and an Y chromosome marker, while no maternal DNA contamination was detected. The direct variant analysis detected F508del heterozygosity and the SNaPshot analysis for R117H detected only the normal allele. Thus, the results showed that the fetuses were healthy carriers of F508del, concordant with the findings of conventional prenatal testing. CONCLUSION: Cell-based NIPT could accurately state the fetal variant status and distinguish fetal trophoblasts from maternal cells. In the future, cell-based NIPT may provide an accurate less invasive alternative to chorionic villous sampling.

Cell-based noninvasive prenatal testing (cbNIPT) detects pathogenic copy number variations.

In two cases, cell-based noninvasive prenatal testing (cbNIPT) detected pathogenic copy number variations (CNVs) in the fetal genome. cbNIPT may potentially be an improved noninvasive alternative for the detection of smaller CNVs.

The Number of Circulating Fetal Extravillous Trophoblasts Varies from Gestational Week 6 to 20.

Cell-based non-invasive prenatal testing (cbNIPT) based on circulating fetal extravillous trophoblasts (fEVTs) has shown to be possible in gestational week (GW) 10-13. Prenatal testing is relevant for a wider time period than GW 10-13, but it is unclear if fEVTs are present in sufficient numbers for cbNIPT at other time points during pregnancy. We present the first longitudinal study where the number of circulating fEVTs was determined from the mid first trimester to the mid second, specifically GW 6-8, 12-13, and 19-20. Blood samples from 13 women opting for assisted reproduction were collected at GW 6-8, 12-13, and 19-20. fEVTs were enriched using a magnetic-activated cell sorting system, stained with anti-cytokeratin antibodies, and fEVTs were identified with the use of a MetaSystem fluorescence microscope scanner. Blood samples drawn at GW 6-8 yielded an average of 5.5 fEVTs per 30 mL of blood. This increased significantly to an average of 11.8 in GW 12-13 (P value: 0.0070, Mann-Whitney test), and decreased significantly to an average of 5.3 in GW 19-20 (P value: 0.0063, Mann-Whitney test). In 9 out of 13 cases, the number of fEVTs peaked in GW 12-13 compared to GW 6-8 and GW 19-20. For the majority of cases, fEVTs can be identified at GW 6-8 and GW 19-20, but the highest number of fEVTs is observed at GW 12-13 indicating this is the optimal time point for cbNIPT.

Do fetal extravillous trophoblasts circulate in maternal blood postpartum?

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.