GM-CSF treatment of frozen bovine sperm improves function, fertilization, and subsequent embryo development.

In vitro embryo production (IVP) is used in the cattle industry to increase the rate of genetic gain. IVP uses semen that has been frozen and thawed, a process that renders sperm less viable than sperm from fresh semen. Granulocyte macrophage colony stimulating factor (GM-CSF) is present in bovine seminal plasma, while its receptor is present on bovine sperm.

Quantifying DNA damage following light sheet and confocal imaging of the mammalian embryo.

Embryo quality assessment by optical imaging is increasing in popularity. Among available optical techniques, light sheet microscopy has emerged as a superior alternative to confocal microscopy due to its geometry, enabling faster image acquisition with reduced photodamage to the sample. However, previous assessments of photodamage induced by imaging may have failed to measure more subtle impacts.

Viewing early life without labels: optical approaches for imaging the early embryo†.

Embryo quality is an important determinant of successful implantation and a resultant live birth. Current clinical approaches for evaluating embryo quality rely on subjective morphology assessments or an invasive biopsy for genetic testing. However, both approaches can be inherently inaccurate and crucially, fail to improve the live birth rate following the transfer of in vitro produced embryos.

Learning algorithms for identification of whisky using portable Raman spectroscopy.

Reliable identification of high-value products such as whisky is vital due to rising issues of brand substitution and quality control in the industry. We have developed a novel framework that can perform whisky analysis directly from raw spectral data with no human intervention by integrating machine learning models with a portable Raman device. We demonstrate that machine learning models can achieve over 99% accuracy in brand or product identification across twenty-eight commercial samples.

A micro-fabricated device (microICSI) improves porcine blastocyst development and procedural efficiency for both porcine intracytoplasmic sperm injection and human microinjection.

Purpose: Intracytoplasmic sperm injection (ICSI) imparts physical stress on the oolemma of the oocyte and remains among the most technically demanding skills to master, with success rates related to experience and expertise. ICSI is also time-consuming and requires workflow management in the laboratory. This study presents a device designed to reduce the pressure on the oocyte during injection and investigates if this improves embryo development in a porcine model.

UVA Hyperspectral Light-Sheet Microscopy for Volumetric Metabolic Imaging: Application to Preimplantation Embryo Development.

Cellular metabolism is a key regulator of energetics, cell growth, regeneration, and homeostasis. Spatially mapping the heterogeneity of cellular metabolic activity is of great importance for unraveling the overall cell and tissue health. In this regard, imaging the endogenous metabolic cofactors, nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavin adenine dinucleotide (FAD), with subcellular resolution and in a noninvasive manner would be useful to determine tissue and cell viability in a clinical environment, but practical use is limited by current imaging techniques.

Dynamic regulation of semaphorin 7A and adhesion receptors in ovarian follicle remodeling and ovulation.

The ovarian follicle is a complex structure that protects and helps in the maturation of the oocyte, and then releases it through the controlled molecular and structural remodeling process of ovulation. The progesterone receptor (PGR) has been shown to be essential in regulating ovulation-related gene expression changes. In this study, we found disrupted expression of the cellular adhesion receptor gene in the granulosa cells of PGR mice during ovulation.

Investigation of refractive index dynamics during embryo development using off-axis digital holographic microscopy.

Embryo quality is a crucial factor affecting live birth outcomes. However, an accurate diagnostic for embryo quality remains elusive in the fertilization clinic. Determining physical parameters of the embryo may offer key information for this purpose.

Nano-liter perfusion microfluidic device made entirely by two-photon polymerization for dynamic cell culture with easy cell recovery.

Polydimethylsiloxane (PDMS) has been the material of choice for microfluidic applications in cell biology for many years, with recent advances encompassing nano-scaffolds and surface modifications to enhance cell-surface interactions at nano-scale. However, PDMS has not previously been amenable to applications which require complex geometries in three dimensions for cell culture device fabrication in the absence of additional components. Further, PDMS microfluidic devices have limited capacity for cell retrieval following culture without severely compromising cell health.

Non-invasive assessment of oocyte developmental competence.

Oocyte quality is a key factor influencing IVF success. The oocyte and surrounding cumulus cells, known collectively as the cumulus oocyte complex (COC), communicate bi-directionally and regulate each other's metabolic function to support oocyte growth and maturation. Many studies have attempted to associate metabolic markers with oocyte quality, including metabolites in follicular fluid or 'spent medium' following maturation, gene expression of cumulus cells and measuring oxygen consumption in medium surrounding COCs.

Experimentally unsupervised deconvolution for light-sheet microscopy with propagation-invariant beams.

Deconvolution is a challenging inverse problem, particularly in techniques that employ complex engineered point-spread functions, such as microscopy with propagation-invariant beams. Here, we present a deep-learning method for deconvolution that, in lieu of end-to-end training with ground truths, is trained using known physics of the imaging system. Specifically, we train a generative adversarial network with images generated with the known point-spread function of the system, and combine this with unpaired experimental data that preserve perceptual content.

Vitrification within a nanoliter volume: oocyte and embryo cryopreservation within a 3D photopolymerized device.

Purpose: Vitrification permits long-term banking of oocytes and embryos. It is a technically challenging procedure requiring direct handling and movement of cells between potentially cytotoxic cryoprotectant solutions. Variation in adherence to timing, and ability to trace cells during the procedure, affects survival post-warming.

Optical imaging detects metabolic signatures associated with oocyte quality†.

Oocyte developmental potential is intimately linked to metabolism. Existing approaches to measure metabolism in the cumulus oocyte complex (COC) do not provide information on the separate cumulus and oocyte compartments. Development of an assay that achieves this may lead to an accurate diagnostic for oocyte quality.

The effect of discrete wavelengths of visible light on the developing murine embryo.

Purpose: A current focus of the IVF field is non-invasive imaging of the embryo to quantify developmental potential. Such approaches use varying wavelengths to gain maximum biological information. The impact of irradiating the developing embryo with discrete wavelengths of light is not fully understood.

Intraovarian, Isoform-Specific Transcriptional Roles of Progesterone Receptor in Ovulation.

Progesterone receptor (PGR) activity is obligatory for mammalian ovulation; however, there is no established direct functional pathway explaining how progesterone receptor completely and specifically regulates oocyte release. This study examined the overarching cell- and isoform-specific effects of the PGR within each cellular compartment of the ovary, using mice null for the PGR (PRKO), as well as isoform-specific null mice. The PGR was expressed in ovarian granulosa and stromal cells and although PRKO ovaries showed no visible histological changes in preovulatory ovarian morphology, follicle rupture did not occur.

Fabrication on the microscale: a two-photon polymerized device for oocyte microinjection.

Purpose: Intracytoplasmic sperm injection (ICSI) addresses male sub-fertility by injecting a spermatozoon into the oocyte. This challenging procedure requires the use of dual micromanipulators, with success influenced by inter-operator expertise. We hypothesized that minimizing oocyte handling during ICSI will simplify the procedure.

Does artificial intelligence have a role in the IVF clinic?

The success of IVF has remained stagnant for a decade. The focus of a great deal of research is to improve on the current ~30% success rate of IVF. Artificial intelligence (AI), or machines that mimic human intelligence, has been gaining traction for its potential to improve outcomes in medicine, such as cancer diagnosis from medical images.

Non-invasive, label-free optical analysis to detect aneuploidy within the inner cell mass of the preimplantation embryo.

Study Question: Can label-free, non-invasive optical imaging by hyperspectral autofluorescence microscopy discern between euploid and aneuploid cells within the inner cell mass (ICM) of the mouse preimplantation embryo?

Summary Answer: Hyperspectral autofluorescence microscopy enables discrimination between euploid and aneuploid ICM in mouse embryos.

What Is Known Already: Euploid/aneuploid mosaicism affects up to 17.3% of human blastocyst embryos with trophectoderm biopsy or spent media currently utilized to diagnose aneuploidy and mosaicism in clinical in vitro fertilization.

Dysregulation of bisphosphoglycerate mutase during in vitro maturation of oocytes.

Purpose: Oxygen is vital for oocyte maturation; however, oxygen regulation within ovarian follicles is not fully understood. Hemoglobin is abundant within the in vivo matured oocyte, indicating potential function as an oxygen regulator. However, hemoglobin is significantly reduced following in vitro maturation (IVM).

Effect of oxygen and glucose availability during in vitro maturation of bovine oocytes on development and gene expression.

Purpose: Oxygen tension during the in vitro maturation (IVM) of oocytes is important for oocyte developmental competence. A conflict exists in the literature as to whether low oxygen during IVM is detrimental or beneficial to the oocyte. Many research and clinical labs use higher than physiological oxygen tension perhaps believing that low-oxygen tension is detrimental to oocyte development.

HYPOXIA AND REPRODUCTIVE HEALTH: Hypoxia and ovarian function: follicle development, ovulation, oocyte maturation.

The ovarian follicle provides the oocyte with the ideal environment for growth and development in preparation for ovulation and fertilisation. The follicle undergoes many structural changes as it grows, including changes in vasculature, cell proliferation and differentiation and the formation of a fluid-filled antrum. These changes collectively create a low oxygen environment within the follicle.

Metabolic co-dependence of the oocyte and cumulus cells: essential role in determining oocyte developmental competence.

Background: Within the antral follicle, the oocyte is reliant on metabolic support from its surrounding somatic cells. Metabolism plays a critical role in oocyte developmental competence (oocyte quality). In the last decade, there has been significant progress in understanding the metabolism of the cumulus-oocyte complex (COC) during its final stages of growth and maturation in the follicle.

A Bimane-Based Peptide Staple for Combined Helical Induction and Fluorescent Imaging.

The thiol-selective fluorescent imaging agent, dibromobimane, has been repurposed to crosslink cysteine- and homocysteine-containing peptides, with the resulting bimane linker acting as both a structural constraint and a fluorescent tag. Macrocyclisation was conducted on nine short peptides containing two cysteines and/or homocysteines, both on-resin and in buffered aqueous solution, to give macrocycles ranging in size from 16 (i,i+2) to 31 (i,i+7) atoms. The structures were defined by CD, NMR structure calculations by using Xplor-NIH, NMR secondary shift and J analyses to reveal helical structure in the i,i+4 (1, 2), and i,i+3 (5) constrained peptides.