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1. Selecting active matter according to motility in an acoustofluidic setup: Self-propelled particles and sperm cells

Author

Misko, V. R., Baraban, L., Makarov, D., Huang, T., Gelin, P., Mateizel, I., Wouters, K., De Munck, N., Nori, F., and De Malsche, W.

Subjects
Condensed Matter - Soft Condensed Matter, Physics - Biological Physics, Physics - Chemical Physics, Physics - Fluid Dynamics, Physics - Medical Physics
Abstract

Active systems -- including sperm cells, living organisms like bacteria, fish, birds, or active soft matter systems like synthetic ''microswimmers'' -- are characterized by motility, i.e., the ability to propel using their own ''engine''. Motility is the key feature that distinguishes active systems from passive or externally driven systems. In a large ensemble, motility of individual species can vary in a wide range. Selecting active species according to their motility represents an exciting and challenging problem. We propose a new method for selecting active species based on their motility using an acoustofluidic setup where highly motile species escape from the acoustic trap. This is demonstrated in simulations and in experiments with self-propelled Janus particles and human sperm. The immediate application of this method is selecting highly motile sperm for medically assisted reproduction (MAR). Due to the tunable acoustic trap, the proposed method is more flexible than the existing passive microfluidic methods. The proposed selection method based on motility can also be applied to other active systems that require selecting highly motile species or removing immotile species., Comment: 18 pages, 4 figures (preliminary version)

Published
2024
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18. How to identify patients who would benefit from delayed-matured oocytes insemination: a sibling oocyte and ploidy outcome study

Author

Elkhatib, I, Nogueira, D, Bayram, A, Abdala, A, Del Gallego, R, Melado, L, De Munck, N, Lawrenz, B, Fatemi, H, Elkhatib, I, Nogueira, D, Bayram, A, Abdala, A, Del Gallego, R, Melado, L, De Munck, N, Lawrenz, B, and Fatemi, H

Abstract

STUDY QUESTION Which patients might benefit from insemination of delayed-matured oocytes? SUMMARY ANSWER Delayed-matured oocytes had a ≥50% contribution to the available cohort of biopsied blastocysts in patients with advanced maternal age, low maturation, and/or low fertilization rates. WHAT IS KNOWN ALREADY Retrieved immature oocytes that progress to the MII stage in vitro could increase the number of embryos available during ICSI cycles. However, these delayed-matured oocytes are associated with lower fertilization rates and compromised embryo quality. Data on the ploidy of these embryos are controversial, but studies failed to compare euploidy rates of embryos derived from delayed-matured oocytes to patients’ own immediate mature sibling oocytes. This strategy efficiently allows to identify the patient population that would benefit from this approach. STUDY DESIGN, SIZE, DURATION This observational study was performed between January 2019 and June 2021 including a total of 5449 cumulus oocytes complexes from 469 ovarian stimulation cycles, from which 3455 inseminated matured oocytes from ICSI (n = 2911) and IVF (n = 544) were considered as the sibling controls (MII-D0) to the delayed-matured oocytes (MII-D1) (n = 910). Euploidy rates were assessed between delayed-matured (MII-D1) and mature sibling oocytes (MII-D0) in relation to patients’ clinical characteristics such as BMI, AMH, age, sperm origin, and the laboratory outcomes, maturation, fertilization, and blastocyst utilization rates. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 390 patients undergoing IVF/ICSI, who had at least one metaphase I (MI) or germinal-vesicle (GV) oocyte on the day of oocyte collection (Day 0), which matured in 20–28 h after denudation were included. MI and GV oocytes that matured overnight were inseminated on the following day (Day 1, MII-D1) by ICSI. Only cycles planned for preimplantation genetic testing for aneuploidy using fresh own oocytes were included. MAIN RESULTS A

Published
2023

36. In vitro differentiation of human oocyte-like cells from oogonial stem cells: single-cell isolation and molecular characterization

Author

Blockeel, C., Racca, A., De Munck, N., Santos-Ribeiro, S., Valenzuela, J. Errazuriz, Drakopoulos, P., Galvao, A., De Vos, M., Tournaye, H., Surgical clinical sciences, Reproduction and Genetics, Centre for Reproductive Medicine - Gynaecology, Faculty of Medicine and Pharmacy, Follicle Biology, and Biology of the Testis

Subjects
0301 basic medicine, Ovarian Cortex, Growth Differentiation Factor 9, Cell Cycle Proteins, Synaptonemal complex protein 3, Cell Separation, In Vitro Techniques, Growth differentiation factor-9, ovarian neo-oogenesis, Oogenesis, Germline, Oogonial Stem Cells, DEAD-box RNA Helicases, Andrology, 03 medical and health sciences, Obstetrics and Gynaecology, medicine, Humans, oocytes, In Situ Hybridization, Fluorescence, oogonial stem cells, biology, medicine.diagnostic_test, Rehabilitation, Nuclear Proteins, DEAD box polypeptide 4, Obstetrics and Gynecology, Cell Differentiation, single-cell isolation, DNA-Binding Proteins, 030104 developmental biology, Reproductive Medicine, biology.protein, Female, Antibody, Fluorescence in situ hybridization
Abstract

STUDY QUESTION Are the large cells derived from cultured DEAD box polypeptide 4 (DDX4)-positive oogonial stem cells (OSCs), isolated from the ovarian cortex of non-menopausal and menopausal women, oocyte-like cells? SUMMARY ANSWER Under appropriate culture conditions, DDX4-positive OSCs from non-menopausal and menopausal women differentiate into large haploid oocyte-like cells expressing the major oocyte markers growth differentiation factor 9 (GDF-9) and synaptonemal complex protein 3 (SYCP3) and then enter meiosis. WHAT IS KNOWN ALREADY The recent reports of OSCs in the ovaries of non-menopausal and menopausal women suggest that neo-oogenesis is inducible during ovarian senescence. However, several questions remain regarding the isolation of these cells, their spontaneous maturation in vitro, and the final differentiation state of the resulting putative oocytes. STUDY DESIGN, SIZE, DURATION DDX4-positive OSCs were obtained from 19 menopausal and 13 non-menopausal women (who underwent hysterectomy for uterine fibroma, ovarian cyst, or other benign pathologies) and cultured for up to 3 weeks. Large and small cells were individually isolated and typed for early and late differentiation markers. PARTICIPANTS/MATERIALS, SETTING, METHODS Ovarian cortex fragments were processed by immuno-magnetic separation using a rabbit anti-human DDX4 antibody and the positive populations were measured by assessing both FRAGILIS and stage-specific embryonic antigen 4 (SSEA-4) expression. After 3 weeks in culture, large oocyte-like cells were individually isolated by DEPArray based on PKH26 red staining and cell size determination. GDF-9 and SYCP3 as final, and developmental pluripotency-associated protein 3 (DPPA3) as primordial, germline markers were measured by droplet digital PCR. The haploid versus diploid chromosomal content of chromosomes X and 5 was investigated using fluorescence in situ hybridization (FISH). MAIN RESULTS AND THE ROLE OF CHANCE SSEA-4 + and FRAGILIS + subsets of DDX4-positive populations were present at lower mean levels in menopausal (SSEA-4 +: 46.7%; FRAGILIS +: 47.5%) than in non-menopausal (SSEA-4 +: 64.9%; FRAGILIS +: 64.8) women (P < 0.05). A comparison of the women's age with the ratio of DDX4-positive cells/cm 3 of ovarian cortex revealed an inverse correlation with OSC number (P < 0.05). Once cultured, cells from both groups differentiated to form large (up to 80 μm) mature oocyte-like cells with typical oocyte morphology. Despite the higher numbers of these cells in cultures from non-menopausal women (37.4 versus 23.7/well; P < 0.001), the intra-culture percentages of large oocyte-like cells did not differ significantly between the two groups. Single large oocyte-like cells isolated from non-menopausal and menopausal women expressed equivalent levels of GDF-9 (e.g. 2.0 and 2.6 copies/μl RNA, respectively) and SYCP3 (e.g. 1.2 and 1.5 copies/μl RNA, respectively) mRNA. The remaining small cells isolated from the cultures expressed large amounts of DPPA3 mRNA (e.g. 5.0 and 5.1 copies/μl RNA, from menopausal and non-menopausal women, respectively), which was undetectable in the large oocyte-like cells. FISH analysis of the large and small cells using probes for chromosomes X and 5 revealed a single signal in the large cells, indicative of chromosome haploidy, whereas in the small cells two distinct signals for each chromosome indicated diploidy. LARGE SCALE DATA Not applicable. LIMITATIONS, REASONS FOR CAUTION Our study demonstrated the final differentiation of OSCs, collected from the ovarian cortex of adult women, to oocyte-like cells. However, because the rate of differentiation was low, a major role of the stem cell niche housing these OSCs cannot be ruled out. WIDER IMPLICATIONS OF THE FINDINGS Since the ability of OSCs to generate mature oocytes in vitro is highly variable, the viability of these cells in the ovarian cortex of non-menopausal and menopausal women may well be determined by the stem cell niche and the woman's concurrent reproductive state. Our study showed that the oocyte-like cells obtained by OSC differentiation in vitro, including those from the OSCs of menopausal women, express markers of meiosis. This model of ovarian neo-oogenesis will contribute to the development of approaches to treat female infertility. STUDY FUNDING/COMPETING INTEREST(S) The study was funded by Italian Association for Cancer Research (IG grant 17536), and from the Apulia Region ('Oncogenomic Project' and 'Jonico-Salentino Project'). All Authors declare no competing interests.

Published
2018
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39. Do we need to measure progesterone in oocyte donation cycles? A retrospective analysis evaluating cumulative live birth rates and embryo quality

Author

Racca, A, primary, De Munck, N, additional, Santos-Ribeiro, S, additional, Drakopoulos, P, additional, Errazuriz, J, additional, Galvao, A, additional, Popovic, B, additional, Mackens, S, additional, De Vos, M, additional, Verheyen, G, additional, Tournaye, H, additional, and Blockeel, C, additional

Published
2020
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43. Artificial frozen embryo transfer cycles: how important are the circulating estradiol (E2) levels for live birth rates?

Author

Orinx, E., Mackens, S., Santos-Ribeiro, S., De Munck, N., Racca, A., Popovic-Todorovic, B., Tournaye, H., Blockeel, C., De Vos, M., Obstetrics, Faculty of Medicine and Pharmacy, Centre for Reproductive Medicine - Gynaecology, Reproductive immunology and implantation, Surgical clinical sciences, Reproduction and Genetics, Biology of the Testis, and Follicle Biology

Published
2018

46. Expanding the time interval between ovulation triggering and oocyte injection: does it affect the embryological and clinical outcome?

Author

Vandenberghe, L T M, Santos-Ribeiro, S, Munck, N De, Desmet, B, Meul, W, Vos, A De, Velde, H Van de, Racca, A, Tournaye, H, Verheyen, G, De Munck, N, De Vos, A, and Van de Velde, H

Subjects
BIRTH rate, OVUM, RETROSPECTIVE studies, FERTILIZATION in vitro, INDUCED ovulation, OVULATION
Abstract

Study Question: Is the time interval between ovulation triggering and oocyte denudation/injection associated with embryological and clinical outcome after ICSI?Summary Answer: Expanding the time interval between ovulation triggering and oocyte denudation/injection is not associated with any clinically relevant impact on embryological or clinical outcome.What Is Known Already: The optimal time interval between ovulation triggering and insemination/injection appears to be 38-39 h and most authors agree that an interval of >41 h has a negative influence on embryological and clinical pregnancy outcomes. However, in ART centres with a heavy workload, respecting these exact time intervals is frequently challenging. Therefore, we questioned to what extent a wider time interval between ovulation triggering and oocyte injection would affect embryological and clinical outcome in ICSI cycles.Study Design, Size, Duration: A single-centre retrospective cohort analysis was performed including 8811 ICSI cycles from 2010 until 2015. Regarding the time interval between ovulation triggering and oocyte injection, seven categories were considered: <36 h, 36 h, 37 h, 38 h, 39 h, 40 h and ≥41 h. In all cases, denudation was performed immediately prior to injection. The main outcome measures were oocyte maturation, fertilization and embryo utilization rate (embryos adequate for transfer or cryopreservation) per fertilized oocyte. Clinical pregnancy rate (CPR) and live birth rate (LBR) were considered as secondary outcomes. Utilization rate, CPR and LBR were subdivided into two groups according to the day of embryo transfer: Day 3 or Day 5.Participants/materials, Setting, Methods: During the study period, oocyte retrieval was routinely performed 36 h post-triggering except in the <36 h group. The interval of <36 h occurred only if OR was carried out before the planned 36 h trigger interval and was followed by immediate injection. Only cycles with fresh autologous gametes were included. The exclusion criteria were: injection with testicular/epididymal sperm, managed natural cycles, conventional IVF, combined conventional IVF/ICSI, preimplantation genetic testing and IVM cycles. Female age, number of oocytes, pre-preparation sperm concentration, post-preparation sperm concentration and motility, day of transfer, number of embryos transferred and quality of the best embryo transferred were identified as potential confounders.Main Results and the Role Of Chance: Among the seven interval groups, adjusted mean maturation rates ranged from 76.4% to 83.2% and differed significantly (P < 0.001). Similarly, there was a significant difference in adjusted mean fertilization rates (range 69.2-79.3%; P < 0.001). The adjusted maturation and fertilization rates were significantly higher when denudation/injection was performed >41 h post-triggering compared to 38 h post-triggering (reference group). Oocyte denudation/injection at <36 h post-triggering had no significant effect on maturation, fertilization or embryo utilization rates compared to injection at 38 h. No effect of the time interval was observed on CPRs and LBRs, after adjusting for potential confounders. When oocyte injection was performed before 36 h the adjusted analysis showed that compared to 38 h after ovulation triggering the chance of having a live birth tends to be lower although the difference was not statistically significant (odds ratio 0.533, 95% CI: 0.252-1.126; P = 0.099). Injection ≥41 h post-triggering did not affect LBR compared to injection at 38 h post-ovulation.Limitations, Reasons For Caution: As this is a large retrospective study, the influence of uncontrolled variables cannot be excluded. These results should not be extrapolated to other ART procedures such as IVM, conventional IVF or injection with testicular/epididymal sperm.Wider Implications Of the Findings: Our results indicate that the optimal injection time window may be less stringent than previously thought as both embryological and clinical outcome parameters were not significantly affected in our analysis. This is reassuring for busy ART centres that might not always be able to follow strict time intervals.Study Funding/competing Interest(s): No funding. The authors declare no conflict of interest related to the present study.Trial Registration Number: N/A. [ABSTRACT FROM AUTHOR]

Published
2021
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47. Elevated progesterone levels negatively influence cumulative live birth rates by affecting both endometrial receptivity and embryonic competence

Author

Racca, A., Santos-Ribeiro, S., De Munck, N., Mackens, S., Mateizel, I., Camus, M., Verheyen, G., Tournaye, H., Blockeel, C., Centre for Reproductive Medicine - Gynaecology, Faculty of Medicine and Pharmacy, Surgical clinical sciences, Department of Embryology and Genetics, Reproductive immunology and implantation, Reproduction and Genetics, and Biology of the Testis

Published
2017

50. Outcome of vitrified-warmed blastocysts derived from poor-quality cleavage stage embryos

Author

Cauffman, G., Van Landuyt, L., De Munck, N., Tournaye, H., Van De Velde, H., Verheyen, G., Department of Embryology and Genetics, Gyneacology-Urology, Reproduction and Genetics, Surgical clinical sciences, Biology of the Testis, Basic (bio-) Medical Sciences, and Reproductive immunology and implantation

Subjects
embryo quality, Vitrification
Published
2015

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