Use of artificial intelligence embryo selection based on static images to predict first-trimester pregnancy loss.

RESEARCH QUESTION: Can an artificial intelligence embryo selection assistant predict the incidence of first-trimester spontaneous abortion using static images of IVF embryos? DESIGN: In a blind, retrospective study, a cohort of 172 blastocysts from IVF cases with single embryo transfer and a positive biochemical pregnancy test was ranked retrospectively by the artificial intelligence morphometric algorithm ERICA. Making use of static embryo images from a light microscope, each blastocyst was assigned to one of four possible groups (optimal, good, fair or poor), and linear regression was used to correlate the results with the presence or absence of a normal fetal heart beat as an indicator of ongoing pregnancy or spontaneous abortion, respectively. Additional analyses included modelling for recipient age and chromosomal status established by preimplantation genetic testing for aneuploidy (PGT-A). RESULTS: Embryos classified as optimal/good had a lower incidence of spontaneous abortion (16.1%) compared with embryos classified as fair/poor (25%; OR = 0.46, P = 0.005). The incidence of spontaneous abortion in chromosomally normal embryos (determined by PGT-A) was 13.3% for optimal/good embryos and 20.0% for fair/poor embryos, although the difference was not significant (P = 0.531). There was a significant association between embryo rank and recipient age (P = 0.018), in that the incidence of spontaneous abortion was unexpectedly lower in older recipients (21.3% for age ≤35 years, 17.9% for age 36-38 years, 16.4% for age ≥39 years; OR = 0.354, P = 0.0181). Overall, these results support correlation between risk of spontaneous abortion and embryo rank as determined by artificial intelligence; classification accuracy was calculated to be 67.4%. CONCLUSIONS: This preliminary study suggests that artificial intelligence (ERICA), which was designed as a ranking system to assist with embryo transfer decisions and ploidy prediction, may also be useful to provide information for couples on the risk of spontaneous abortion. Future work will include a larger sample size and karyotyping of miscarried pregnancy tissue.

Sustainability in the IVF laboratory: recommendations of an expert panel.

The healthcare industry is a major contributor to greenhouse gas emissions. Assisted reproductive technology is part of the larger healthcare sector, with its own heavy carbon footprint. The social, economic and environmental costs of this collective carbon footprint are becoming clearer, as is the impact on human reproductive health. Alpha Scientists in Reproductive Medicine and the International IVF Initiative collaborated to seek and formulate practical recommendations for sustainability in IVF laboratories. An international panel of experts, enthusiasts and professionals in reproductive medicine, environmental science, architecture, biorepository and law convened to discuss the topics of importance to sustainability. Recommendations were issued on how to build a culture of sustainability in the workplace, implement green design and building, use life cycle analysis to determine the environmental impact, manage cryostorage more sustainably, and understand and manage laboratory waste with prevention as a primary goal. The panel explored whether the industry supporting IVF is sustainable. An example is provided to illustrate the application of green principles to an IVF laboratory through a certification programme. The UK legislative landscape surrounding sustainability is also discussed and a few recommendations on 'Green Conferencing' are offered.

The Internet of Things in assisted reproduction.

The Internet of Things (IoT) is a network connecting physical objects with sensors, software and internet connectivity for data exchange. Integrating the IoT with medical devices shows promise in healthcare, particularly in IVF laboratories. By leveraging telecommunications, cybersecurity, data management and intelligent systems, the IoT can enable a data-driven laboratory with automation, improved conditions, personalized treatment and efficient workflows. The integration of 5G technology ensures fast and reliable connectivity for real-time data transmission, while blockchain technology secures patient data. Fog computing reduces latency and enables real-time analytics. Microelectromechanical systems enable wearable IoT and miniaturized monitoring devices for tracking IVF processes. However, challenges such as security risks and network issues must be addressed through cybersecurity measures and networking advancements. Clinical embryologists should maintain their expertise and knowledge for safety and oversight, even with IoT in the IVF laboratory.

Computer software (SiD) assisted real-time single sperm selection associated with fertilization and blastocyst formation.

RESEARCH QUESTION: Is it possible to explore an association between individual sperm kinematics evaluated in real time and spermatozoa selected by an embryologist for intracytoplasmic sperm injection (ICSI), with subsequent normal fertilization and blastocyst formation using a novel artificial vision-based software (SiD V1.0; IVF 2.0, UK)? DESIGN: ICSI procedures were randomly video recorded and subjected to analysis using SiD V1.0, proprietary software developed by our group. In total, 383 individual spermatozoa were retrospectively analysed from a dataset of 78 ICSI-assisted reproductive technology cycles. SiD software computes the progressive motility parameters, straight-line velocity (VSL) and linearity of the curvilinear path (LIN), of each sperm trajectory, along with a quantitative value, head movement pattern (HMP), which is an indicator of the characteristics of the sperm head movement patterns. The mean VSL, LIN and HMP measurements for each set of spermatozoa were compared based on different outcome measures. RESULTS: Statistically significant differences were found in VSL, LIN and HMP among those spermatozoa selected for injection (P < 0.001). Additionally, LIN and HMP were found to be significantly different between successful and unsuccessful fertilization (P = 0.038 and P = 0.029, respectively). Additionally, significantly higher SiD scores were found for those spermatozoa that achieved both successful fertilization (P = 0.004) and blastocyst formation (P = 0.013). CONCLUSION: The possibility of carrying out real-time analyses of individual spermatozoa using an automatic tool such as SiD creates the opportunity to assist the embryologist in selecting the better spermatozoon for injection in an ICSI procedure.

[Passive immunotherapy in Sars-Cov2 infections]. / Immunothérapies passives dans l'infection par le SARS-CoV-2.

This article presents the current situation by November 2021 of the prophylactic or therapeutical use of polyclonal or monoclonal antibodies in Covid-19, either as immuno-modulators, or directly directed towards the virus.

Embryo Ranking Intelligent Classification Algorithm (ERICA): artificial intelligence clinical assistant predicting embryo ploidy and implantation.

RESEARCH QUESTION: Can a deep machine learning artificial intelligence algorithm predict ploidy and implantation in a known data set of static blastocyst images, and how does its performance compare against chance and experienced embryologists? DESIGN: A database of blastocyst images with known outcome was applied with an algorithm dubbed ERICA (Embryo Ranking Intelligent Classification Algorithm). It was evaluated against its ability to predict euploidy, compare ploidy prediction against randomly assigned prognosis labels and against senior embryologists, and if it could rank an euploid embryo highly. RESULTS: A total of 1231 embryo images were classed as good prognosis if euploid and implanted or poor prognosis if aneuploid and failed to implant. An accuracy of 0.70 was obtained with ERICA, with positive predictive value of 0.79 for predicting euploidy. ERICA had greater normalized discontinued cumulative gain (ranking metric) than random selection (P = 0.0007), and both embryologists (P = 0.0014 and 0.0242, respectively). ERICA ranked an euploid blastocyst first in 78.9% and at least one euploid embryo within the top two blastocysts in 94.7% of cases, better than random classification and the two senior embryologists. Average embryo ranking time for four blastocysts was under 25 s. CONCLUSION: Artificial intelligence lends itself well to image pattern recognition. We have trained ERICA to rank embryos based on ploidy and implantation potential using single static embryo image. This tool represents a potentially significant advantage to assist embryologists to choose the best embryo, saving time spent annotating and does not require time lapse or invasive biopsy. Future work should be directed to evaluate reproducibility in different data sets.

Comparison of 36 assisted reproduction laboratories monitoring environmental conditions and instrument parameters using the same quality-control application.

RESEARCH QUESTION: Assisted reproduction laboratories record instrument performance periodically. No standardized guidelines have been produced for this activity despite mandatory auditing systems in several countries. This study of 36 laboratories in 12 different countries was conducted to assess differences and similarities between quality assurance programmes using an adaptable cloud-based quality-control app for instrument monitoring. DESIGN: A total of 36 deidentified IVF laboratories that subscribed to the same quality-assurance application were studied. Data were evaluated based on instrument types allocated to 10 domains: incubators, gas tanks, warming surfaces, refrigerators and freezers, cryo-storage, environment, water purification, peripheral equipment, checklists and miscellaneous. RESULTS: The incubator domain constituted the greatest proportion of parameters (35%), followed by surface warming instruments at 15%. Most incubator O2 readings were monitored between 4.5 and 5.5%, and between 5.5 and 6.5% for CO2. The altitude of the laboratory was poorly correlated with the CO2 setting. Incubator display and measured values of gases and temperature by built-in sensors vary considerably compared with third-party sensors. A quality-control diligence score or mean average data points was calculated for each laboratory. This score is independent of number of instruments or laboratory size. Higher scores were associated with laboratories in countries with government regulations and mandatory auditing systems. CONCLUSIONS: Major differences exist in instrument monitoring practices among laboratories. Although incubator monitoring is the largest domain, many other sensitive instruments are diligently monitored by most laboratories. International standardization and guidelines are needed.

Altered levels of mitochondrial DNA are associated with female age, aneuploidy, and provide an independent measure of embryonic implantation potential.

Mitochondria play a vital role in embryo development. They are the principal site of energy production and have various other critical cellular functions. Despite the importance of this organelle, little is known about the extent of variation in mitochondrial DNA (mtDNA) between individual human embryos prior to implantation. This study investigated the biological and clinical relevance of the quantity of mtDNA in 379 embryos. These were examined via a combination of microarray comparative genomic hybridisation (aCGH), quantitative PCR and next generation sequencing (NGS), providing information on chromosomal status, amount of mtDNA, and presence of mutations in the mitochondrial genome. The quantity of mtDNA was significantly higher in embryos from older women (P=0.003). Additionally, mtDNA levels were elevated in aneuploid embryos, independent of age (P=0.025). Assessment of clinical outcomes after transfer of euploid embryos to the uterus revealed that blastocysts that successfully implanted tended to contain lower mtDNA quantities than those failing to implant (P=0.007). Importantly, an mtDNA quantity threshold was established, above which implantation was never observed. Subsequently, the predictive value of this threshold was confirmed in an independent blinded prospective study, indicating that abnormal mtDNA levels are present in 30% of non-implanting euploid embryos, but are not seen in embryos forming a viable pregnancy. NGS did not reveal any increase in mutation in blastocysts with elevated mtDNA levels. The results of this study suggest that increased mtDNA may be related to elevated metabolism and are associated with reduced viability, a possibility consistent with the 'quiet embryo' hypothesis. Importantly, the findings suggest a potential role for mitochondria in female reproductive aging and the genesis of aneuploidy. Of clinical significance, we propose that mtDNA content represents a novel biomarker with potential value for in vitro fertilisation (IVF) treatment, revealing chromosomally normal blastocysts incapable of producing a viable pregnancy.

Inherited and Acquired Decrease in Complement Receptor 1 (CR1) Density on Red Blood Cells Associated with High Levels of Soluble CR1 in Alzheimer's Disease.

The complement receptor 1 (CR1) gene was shown to be involved in Alzheimer's disease (AD). We previously showed that AD is associated with low density of the long CR1 isoform, CR1*2 (S). Here, we correlated phenotype data (CR1 density per erythrocyte (CR1/E), blood soluble CR1 (sCR1)) with genetic data (density/length polymorphisms) in AD patients and healthy controls. CR1/E was enumerated using flow cytometry, while sCR1 was quantified by ELISA. CR1 polymorphisms were assessed using restriction fragment length polymorphism (RFLP), pyrosequencing, and high-resolution melting PCR. In AD patients carrying the H allele (HindIII polymorphism) or the Q allele (Q981H polymorphism), CR1/E was significantly lower when compared with controls carrying the same alleles (p < 0.01), contrary to sCR1, which was significantly higher (p < 0.001). Using multivariate analysis, a reduction of 6.68 units in density was associated with an increase of 1% in methylation of CR1 (estimate -6.68; 95% confidence intervals (CIs) -12.37, -0.99; p = 0.02). Our data show that, in addition to inherited genetic factors, low density of CR1/E is also acquired. The involvement of CR1 in the pathogenesis of AD might be linked to insufficient clearance of amyloid deposits. These findings may open perspectives for new therapeutic strategies in AD.

Deletion of receptor for advanced glycation end products exacerbates lymphoproliferative syndrome and lupus nephritis in B6-MRL Fas lpr/j mice.

The receptor for advanced glycation end products (RAGE) is a pattern recognition receptor that interacts with advanced glycation end products, but also with C3a, CpG DNA oligonucleotides, and alarmin molecules such as HMGB1 to initiate a proinflammatory reaction. Systemic lupus erythematosus is an autoimmune disorder associated with the accumulation of RAGE ligands. We generated mice invalidated for RAGE in the lupus-prone B6-MRL Fas lpr/j background to determine the role of RAGE in the pathogenesis of systemic lupus erythematosus. We compared the phenotype of these mice with that of their wild-type and B6-MRL Fas lpr/j littermates. Lymphoproliferative syndrome, production of anti-dsDNA Abs, lupus nephritis, and accumulation of CD3(+)B220(+)CD4(-)CD8(-) autoreactive T cells (in the peripheral blood and the spleen) were significantly increased in B6-MRL Fas lpr/j RAGE(-/-) mice compared with B6-MRL Fas lpr/j mice (respectively p < 0.005, p < 0.05, p < 0.001, and p < 0.001). A large proportion of autoreactive T cells from B6-MRL Fas lpr/j mice expressed RAGE at their surface. Time course studies of annexin V expression revealed that autoreactive T cells in the spleen of B6-MRL Fas lpr/j-RAGE(-/-) mice exhibited a delay in apoptosis and expressed significantly less activated caspase 3 (39.5 ± 4.3%) than T cells in B6-MRL Fas lpr/j mice (65.5 ± 5.2%) or wild-type mice (75.3 ± 2.64%) (p = 0.02). We conclude that the deletion of RAGE in B6-MRL Fas lpr/j mice promotes the accumulation of autoreactive CD3(+)B220(+)CD4(-)CD8(-) T cells, therefore exacerbating lymphoproliferative syndrome, autoimmunity, and organ injury. This suggests that RAGE rescues the apoptosis of T lymphocytes when the death receptor Fas/CD95 is dysfunctional.

The why, the how and the when of PGS 2.0: current practices and expert opinions of fertility specialists, molecular biologists, and embryologists.

STUDY QUESTION: We wanted to probe the opinions and current practices on preimplantation genetic screening (PGS), and more specifically on PGS in its newest form: PGS 2.0? STUDY FINDING: Consensus is lacking on which patient groups, if any at all, can benefit from PGS 2.0 and, a fortiori, whether all IVF patients should be offered PGS. WHAT IS KNOWN ALREADY: It is clear from all experts that PGS 2.0 can be defined as biopsy at the blastocyst stage followed by comprehensive chromosome screening and possibly combined with vitrification. Most agree that mosaicism is less of an issue at the blastocyst stage than at the cleavage stage but whether mosaicism is no issue at all at the blastocyst stage is currently called into question. STUDY DESIGN, SAMPLES/MATERIALS, METHODS: A questionnaire was developed on the three major aspects of PGS 2.0: the Why, with general questions such as PGS 2.0 indications; the How, specifically on genetic analysis methods; the When, on the ideal method and timing of embryo biopsy. Thirty-five colleagues have been selected to address these questions on the basis of their experience with PGS, and demonstrated by peer-reviewed publications, presentations at meetings and participation in the discussion. The first group of experts who were asked about 'The Why' comprised fertility experts, the second group of molecular biologists were asked about 'The How' and the third group of embryologists were asked about 'The When'. Furthermore, the geographical distribution of the experts has been taken into account. Thirty have filled in the questionnaire as well as actively participated in the redaction of the current paper. MAIN RESULTS AND THE ROLE OF CHANCE: The 30 participants were from Europe (Belgium, Germany, Greece, Italy, Netherlands, Spain, UK) and the USA. Array comparative genome hybridization is the most widely used method amongst the participants, but it is slowly being replaced by massive parallel sequencing. Most participants offering PGS 2.0 to their patients prefer blastocyst biopsy. The high efficiency of vitrification of blastocysts has added a layer of complexity to the discussion, and it is not clear whether PGS in combination with vitrification, PGS alone, or vitrification alone, followed by serial thawing and eSET will be the favoured approach. The opinions range from in favour of the introduction of PGS 2.0 for all IVF patients, over the proposal to use PGS as a tool to rank embryos according to their implantation potential, to scepticism towards PGS pending a positive outcome of robust, reliable and large-scale RCTs in distinct patient groups. LIMITATIONS, REASONS FOR CAUTION: Care was taken to obtain a wide spectrum of views from carefully chosen experts. However, not all invited experts agreed to participate, which explains a lack of geographical coverage in some areas, for example China. This paper is a collation of current practices and opinions, and it was outside the scope of this study to bring a scientific, once-and-for-all solution to the ongoing debate. WIDER IMPLICATIONS OF THE FINDINGS: This paper is unique in that it brings together opinions on PGS 2.0 from all different perspectives and gives an overview of currently applied technologies as well as potential future developments. It will be a useful reference for fertility specialists with an expertise outside reproductive genetics. LARGE SCALE DATA: none. STUDY FUNDING AND COMPETING INTERESTS: No specific funding was obtained to conduct this questionnaire.

A limited survey-based uncontrolled follow-up study of children born after ooplasmic transplantation in a single centre.

Experimental ooplasmic transplantation from donor to recipient oocyte took place between 1996 and 2001 at Saint Barnabas Medical Center, USA. Indication for 33 patients was repeated implantation failure. Thirteen couples had 17 babies. One patient delivered twins from mixed ooplasmic and donor egg embryos. A limited survey-based follow-up study on the children is reported: 12 out of 13 parents completed a questionnaire on pregnancy, birth, health, academic performance and disclosure. Parents of a quadruplet did not participate. Prenatal development and delivery were uneventful. School grades ranged from good to excellent. Children were of good health. Body mass index (BMI) was normal in 12 out of 13 children. One child had chronic migraine headaches, two mild asthma, three minor vision and three minor skin problems. One boy from a boy/girl twin was diagnosed with borderline pervasive developmental disorder - not otherwise specified at age 18 months, but with no later symptoms. One couple disclosed the use of egg donor to their child. One reported intention to disclose; six were undecided and four reported they would not disclose. This limited follow-up strategy presents a high risk of bias. Parents may not assent to standardized clinical analysis owing to lack of disclosure to their children.

Causes and estimated incidences of sex-chromosome misdiagnosis in preimplantation genetic diagnosis of aneuploidy.

Preimplantation genetic diagnosis of aneuploidy (PGD-A) with comprehensive chromosome analysis has been known to improve pregnancy outcomes. Accuracy in detecting sex chromosomes becomes important when selecting against embryos at risk for sex-linked disorders. A total of 21,356 PGD-A cycles consisting of day-3 (cleavage) or day-5 (blastocyst) biopsies were received at the same laboratory for PGD-A via fluorescence in situ hybridization (FISH) or array comparative genome hybridization (aCGH) from multiple fertility centres. The misdiagnosis rates were 0.12% (Wilson 95% CI 0.05 to 0.25%) in day-3 FISH cycles, 0.48% (Wilson 95% CI 0.19 to 1.22%) in day-3 aCGH cycles and 0.0% (Wilson 95% CI 0 to 0.26) in day-5 aCGH cycles. Although rare, the likely causative biological event for true misdiagnosis is embryonic XX/XY mosaicism. Reanalysis of 1219 abnormal cleavage-stage research embryos revealed a 73% incidence of minor and major mosaicism. Only four (0.3%) embryos were found to be diploid and contained XX and XY cells that could potentially account for the misdiagnosis of sex. Our investigation identified errors leading to misdiagnosis and their attribution to specific events during PGD-A testing. The reported misdiagnosis rates suggest that PGD-A for sex determination is highly accurate, particularly when using aCGH applied to blastocyst biopsies.

Detection of carcinoembryonic antigen using single-domain or full-size antibodies stained with quantum dot conjugates.

Compact single-domain antibodies (sdAbs) are nearly 13 times smaller than full-size monoclonal antibodies (mAbs) and have a number of advantages for biotechnological applications, such as small size, high specificity, solubility, stability, and great refolding capacity. Carcinoembryonic antigen (CEA) is a tumor-associated glycoprotein expressed in a variety of cancers. Detection of CEA on the tumor cell surface may be carried out using anti-CEA antibodies and conventional fluorescent dyes. Semiconductor quantum dots (QDs) are brighter and more photostable than organic dyes; they provide the possibility for labeling of different recognition molecules with QDs of different colors but excitable with the same wavelength of excitation. In this study, the abilities for specific detection of CEA expressed by tumor cells with anti-CEA sdAbs biotinylated in vitro and in vivo, as well as with anti-CEA mAbs biotinylated in vitro, were compared using flow cytometry and the conjugates of streptavidin with QDs (SA-QDs). The results demonstrated that either in vitro or in vivo biotinylated anti-CEA sdAbs are more sensitive for cell staining compared to biotinylated anti-CEA mAbs. The data also show that simultaneous use of biotinylated sdAbs with highly fluorescent SA-QDs can considerably improve the sensitivity of detection of CEA on tumor cell surfaces.

Live births achieved via IVF are increased by improvements in air quality and laboratory environment.

Infertility is a common disease, which causes many couples to seek treatment with assisted reproduction techniques. Many factors contribute to successful assisted reproduction technique outcomes. One important factor is laboratory environment and air quality. Our facility had the unique opportunity to compare consecutively used, but separate assisted reproduction technique laboratories, as a result of a required move. Environmental conditions were improved by strategic engineering designs. All other aspects of the IVF laboratory, including equipment, physicians, embryologists, nursing staff and protocols, were kept constant between facilities. Air quality testing showed improved air quality at the new IVF site. Embryo implantation (32.4% versus 24.3%; P < 0.01) and live birth (39.3% versus 31.8%, P < 0.05) were significantly increased in the new facility compared with the old facility. More patients met clinical criteria and underwent mandatory single embryo transfer on day 5 leading to both a reduction in multiple gestation pregnancies and increased numbers of vitrified embryos per patient with supernumerary embryos available. Improvements in IVF laboratory conditions and air quality had profound positive effects on laboratory measures and patient outcomes. This study further strengthens the importance of the laboratory environment and air quality in the success of an IVF programme.

Structural basis for the ABO blood-group dependence of Plasmodium falciparum rosetting.

The ABO blood group influences susceptibility to severe Plasmodium falciparum malaria. Recent evidence indicates that the protective effect of group O operates by virtue of reduced rosetting of infected red blood cells (iRBCs) with uninfected RBCs. Rosetting is mediated by a subgroup of PfEMP1 adhesins, with RBC binding being assigned to the N-terminal DBL1α1 domain. Here, we identify the ABO blood group as the main receptor for VarO rosetting, with a marked preference for group A over group B, which in turn is preferred to group O RBCs. We show that recombinant NTS-DBL1α1 and NTS-DBL1α1-CIDR1γ reproduce the VarO-iRBC blood group preference and document direct binding to blood group trisaccharides by surface plasmon resonance. More detailed RBC subgroup analysis showed preferred binding to group A1, weaker binding to groups A2 and B, and least binding to groups A(x) and O. The 2.8 Å resolution crystal structure of the PfEMP1-VarO Head region, NTS-DBL1α1-CIDR1γ, reveals extensive contacts between the DBL1α1 and CIDR1γ and shows that the NTS-DBL1α1 hinge region is essential for RBC binding. Computer docking of the blood group trisaccharides and subsequent site-directed mutagenesis localized the RBC-binding site to the face opposite to the heparin-binding site of NTS-DBLα1. RBC binding involves residues that are conserved between rosette-forming PfEMP1 adhesins, opening novel opportunities for intervention against severe malaria. By deciphering the structural basis of blood group preferences in rosetting, we provide a link between ABO blood grouppolymorphisms and rosette-forming adhesins, consistent with the selective role of falciparum malaria on human genetic makeup.

Laser-assisted zona pellucida thinning does not facilitate hatching and may disrupt the in vitro hatching process: a morphokinetic study in the mouse.

STUDY QUESTION: Does laser-assisted zona thinning of cleavage stage mouse embryos facilitate hatching in vitro? SUMMARY ANSWER: No, unlike laser zona opening, zona thinning does not facilitate embryo hatching. WHAT IS KNOWN ALREADY: Artificial opening of the zona pellucida facilitates hatching of mouse and human embryos. Laser-assisted zona thinning has also been used for the purpose of assisted hatching of human embryos but it has not been properly investigated in an animal model; thinning methods have produced inconsistent clinical results. STUDY DESIGN, SIZE, DURATION: Time-lapse microscopy was used to study the hatching process in the mouse after zona opening and zona thinning; a control group of embryos was not zona-manipulated but exposed to the same laser energy. PARTICIPANTS/MATERIALS, SETTING, METHODS: Eight-cell CB6F1/J mouse embryos were pooled and allocated to three groups (n = 56 per group): A control group of embryos that were exposed to a dose of laser energy focused outside the zona pellucida (zona intact); one experimental group of embryos in which the zona pellucida was opened by complete ablation using the same total number of pulses as the control group; a second experimental group of embryos in which the zona pellucida was thinned to establish a smooth lased area using the same number of pulses as used in the other two groups. The width of the zona opening was 25 µm and width of the thinned area was 35 µm. Development was monitored by time-lapse microscopy. Overall treatment differences for continuous variables were analyzed by analysis of variance and pairwise comparisons using the Student t-test allowing for unequal variances, while for categorical data, a standard chi-squared test was utilized for all pairwise comparisons. MAIN RESULTS AND THE ROLE OF CHANCE: The frequency of complete hatching was 33.9% in the control group, 94.4% after zona opening, and 39.3% after zona thinning (overall group comparison, P < 0.0001). Overall, 60.7% of the zona-thinned embryos did not complete the hatching process and remained trapped within the zona; when they did hatch, they did not necessarily hatch from the zona-thinned area. Hatching in about one-third of the zona-intact embryos began with breaches at multiple sites by small groups of cells. Likewise, 53.6% of zona-thinned embryos had multiple breaches, always involving an area outside the thinned zone. Zona opening decreased multiple breaching and led to blastocyst escape an average of 14 h earlier than zona-thinned embryos and 5.5 h before control embryos (P = 0.0003). LIMITATIONS, REASONS FOR CAUTION: The experiments presented here were limited to in vitro experiments performed in the mouse. Whether human embryos would behave the same way under similar circumstances is unknown. We postulate that zona thinning is not beneficial in human embryos. WIDER IMPLICATIONS OF THE FINDINGS: The experiments demonstrate that zona thinning is not equivalent to zona opening for assisted hatching. The study provides reason for systematic reviews of assisted hatching trials to take the method of assisted hatching into consideration and not combine the results of zona thinning and zona opening procedures. STUDY FUNDING/COMPETING INTERESTS: Institutional funds were used for the study. No competing interests are declared.

Multiphoton imaging of tumor biomarkers with conjugates of single-domain antibodies and quantum dots.

An ideal multiphoton fluorescent nanoprobe should combine a nanocrystal with the largest possible two-photon absorption cross section (TPACS) and the smallest highly specific recognition molecules bound in an oriented manner. CdSe/ZnS quantum dots (QDs) conjugated to 13-kDa single-domain antibodies (sdAbs) derived from camelid IgG or streptavidin have been used as efficient two-photon excitation (TPE) probes for carcinoembryonic antigen (CEA) imaging on normal human appendix and colon carcinoma tissue. The TPACS for some conjugates was higher than 49,000 GM (Goeppert-Mayer units), considerably exceeding that of organic dyes being close to the theoretical value of 50,000 GM calculated for CdSe QDs. The ratio of sdAb-QD emission to the autofluorescence for 800 nm TPE was 40 times higher than that for 457.9 nm one-photon excitation. TPE ensures a clear discrimination of CEA-overexpressing tumor areas from normal tissue. Oriented sdAb-QD conjugates are bright specific labels for detecting low concentrations of antigens using multiphoton microscopy. FROM THE CLINICAL EDITOR: This study demonstrates carcinoembryonic antigen imaging on normal human appendix and colon carcinoma tissue utilizing CdSe/ZnS quantum dots conjugated to streptavidin or to 13-kDa single-domain antibodies as efficient two-photon excitation probes.

The first clinical validation of whole-genome screening on standard trophectoderm biopsies of preimplantation embryos.

Objective: To validate the performance of our laboratory-developed whole-genome screening assay within clinical preimplantation genetic testing environments. Design: Perform a laboratory-developed whole-genome assay on both cell lines and trophectoderm biopsies, subsequently employing the next-generation sequencing procedure to reach a sequencing depth of 30X. Adhere to the Genome Analysis Toolkit best practices for accuracy, sensitivity, specificity, and precision calculations by comparing samples with references. Our assay was then applied to cell lines and biopsies harboring known pathogenic variants, aiming to ascertain these changes solely from the next-generation sequencing data, independent of parental genome information. Settings: Clinical laboratory. Patients: Coriell cell lines and research embryos with known chromosomal or genetic variants. Research trophectoderm biopsies from a couple that are heterozygous carriers for distinct variants in the same autosomal recessive gene (HOGA1). Intervention: Not applicable. Main Outcome Measures: Accuracy, sensitivity, specificity, and precision were assessed by comparing the samples to their references. For samples with known variants, we calculated our sensitivity to detecting established variants. For the research embryos, noncarrier, carrier, and compound heterozygous states of inherited HOGA1 variants were distinguished independently of parental samples. Results: Amplification of DNA from cell lines and embryos yielded success rates exceeding 99.9% and 98.2%, respectively, although maintaining an accuracy of >99.9% for aneuploidy assessment. The accuracy (99.99%), specificity (99.99%), sensitivity (98.0%), and precision (98.1%) of amplified genome in the bottle (reference NA12878) and embryo biopsies were comparable to results on genomic DNA, including mitochondrial heteroplasmy. Using our assay, we achieved >99.99% sensitivity when examining samples with known chromosomal and genetic variants. This encompassed pathogenic CFTR, BRCA1, and other variants, along with uniparental isodisomies and microdeletions such as DiGeorge syndrome. Our research study identified noncarrier, carrier, and compound heterozygous states within trophectoderm biopsies while simultaneously screening for 1,300 other severe monogenic diseases. Conclusion: To our knowledge, this is the first clinical validation of whole-genome embryo screening. In this study, we demonstrated high accuracy for aneuploidy calls (>99.9%) and genetic variants (99.99%), even in the absence of parental genomes. This assay demonstrates advancements in genomic screening and an extended scope for testing capabilities in the realm of preimplantation genetic testing.