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Lancaster, M. A.

Publications and source records attributed to Lancaster, M. A..

At least 19 recordsLinked to original sources

Human Choroid Plexus Organoids Progress to Postnatal-like Maturation and Reveal a Closing Window of Developmental Plasticity

The choroid plexus (ChP) produces cerebrospinal fluid (CSF) and forms the blood-CSF barrier, yet the developmental programme driving its maturation in humans remains poorly understood. Using a 15-timepoint single-cell RNA sequencing atlas of human ChP organoids benchmarked against human tissue, we resolve an ordered differentiation process comprising cell cycle exit, ciliogenesis and ion transporter expression. Maturation culminates in a transcriptional state with features of human adult ChP, establishing the first in vitro ChP model to reach postnatal-like milestones. Centrosome proteomics identified previously uncharacterised, stage-specific regulators of ciliogenesis. To probe developmental plasticity, we perturbed ChP organoids with valproic acid (VPA), a clinically used antiepileptic and established teratogen. Early VPA-mediated disruption of multiciliogenesis and secretion recovered upon drug withdrawal, whereas late treatment washout resulted in persistent impairment of mature transporters. Together, these findings resolve the developmental programme by which the ChP reaches functionally mature identity and identify a stage-dependent plasticity window during its maturation.

developmental biology↗

Protein-state dysregulation and sex-specific neurodevelopmental signatures in schizophrenia forebrain organoids

Schizophrenia is highly heritable, yet the molecular mechanisms linking genetic risk to abnormal human brain development remain poorly understood. To address this, we generated dorsal forebrain organoids from 17 individuals with idiopathic schizophrenia and 17 age- and sex-matched controls and profiled them across multiple molecular layers, including single-nucleus transcriptomics, quantitative proteomics, metabolomics and deep post-translational modification (PTM) analysis. The organoids reproducibly modelled early cortical development and showed largely similar cellular composition between schizophrenia and control groups. Surprisingly, transcriptomic differences were relatively limited, with the strongest cell-type-specific changes observed in Cajal-Retzius neurons. In contrast, proteomic and particularly PTM-level analyses revealed widespread molecular disruption affecting pathways involved in neuronal migration, neurite development, synaptic function, protein kinase signalling, extracellular matrix organisation and lipid metabolism. Many of the earliest disease-associated changes emerged at the level of protein phosphorylation, consistent with altered neuronal maturation and neurite dynamics. At later developmental stages, schizophrenia organoids showed reduced abundance of synaptic proteins, fewer synaptic puncta and evidence of dysregulated retinoic acid and YAP1 signalling. Notably, most disease-associated alterations occurred independently of changes in transcript or protein abundance, indicating that key aspects of schizophrenia biology are encoded in protein state rather than expression level. These findings identify sex-specific dysregulation of protein state as a major molecular feature of schizophrenia and demonstrate the value of multi-layer proteomic approaches for uncovering disease mechanisms missed by transcriptomics alone.

neuroscience↗

Index-agnostic oblique plane light sheet microscopy of centimetre-scale cleared tissues at subcellular resolution

We present cleared-tissue direct-view oblique plane microscopy (CtDvOPM), which enables optically sectioned subcellular resolution imaging of centimetre-scale tissues at high throughput over the full range of clearing media refractive indices (n = 1.33-1.56). CtDvOPM can image conventionally-mounted expanded, aqueous or non-aqueous cleared tissue samples at up to 2 {micro}m lateral by 14 {micro}m axial resolution over a 10.1 mm x 25.0 mm x 6.8 mm (x x y x z) sample volume without image tiling, at up to 400 million voxels per second.

biophysics↗

Ventricular Forebrain Organoids Reproduce Macroscale Geometry of the Developing Telencephalon

During development, the size of the neuroepithelial cell pool plays a key role in establishing brain size, determining the numbers of derived progenitors and subsequent neuronal cell types. While early histogenesis is well modelled in brain organoids, the organ-scale geometry of the telencephalon is not accurately recapitulated. Herein, we present a new approach for generating ventral and dorsal forebrain organoids which develop a large ventricular neuroepithelium, characteristic of the closed telencephalic vesicle. Using a growth medium that supports aerobic glycolysis and is typically used for endothelial cells, we modulate neuroepithelial expansion to induce a more anatomically accurate neuroepithelial layer which, upon maturation, thickens physiologically to generate the typical neurogenic layered architecture. In addition, we present a new method for embedding organoids in miniature collagen spheres which mimics native extracellular matrix, stabilizes the ventricular geometry for dynamic culture conditions, and provides a means for incorporating vascular cells for neurovascular development. Finally, we demonstrate that human organoids grown under these conditions exhibit dramatically enlarged ventricles and delayed maturation compared to mouse. Together, this approach provides a model of the forebrain neuroepithelium with morphogenetic macroscale geometry and tissue architecture, suitable for investigating neurodevelopment and disease.

bioengineering↗

Maximising imaging volumes of expanded tissues for inverted fluorescence microscopy

Expansion microscopy (ExM) has enabled nanoscale imaging of tissues by physically enlarging biological samples in a swellable hydrogel. However, the increased sample size and water-based environment pose challenges for deep imaging using conventional inverted confocal microscopes, particularly due to the limited working distance of high-numerical aperture (NA) water immersion objectives. Here, we introduce a practical imaging alternative that utilizes an inverted water-dipping objective and a refractive-index-matched optical path using fluorinated ethylene propylene (FEP) film. Through point spread function (PSF) measurements and simulations, we show that the FEP film introduces predominantly defocus-like wavefront profiles characteristic of high NA systems, which result in an easily correctable axial shift of the focal plane. To ensure stable immersion and refractive index continuity, we use an arrangement relying on an FEP film, Immersol W, water and a FEP-based imaging dish. This configuration achieves sub-micron lateral and axial resolution, supports large tile-scan acquisitions, and maintains image quality across depths exceeding 800 {micro}m. We validate the system by imaging 4x-expanded U2OS cells and human cerebral organoids. Our approach provides a low-cost, plug-and-play solution for high-resolution volumetric imaging of expanded samples using standard inverted microscopes.

biophysics↗

Electrophysiological development and functional plasticity in dissociated human cerebral organoids across multiple cell lines

Microelectrode arrays (MEAs) are increasingly used to profile the development of synchronised activity in neural organoids, yet no organoid study has investigated the consistency of electrophysiological development across cell lines. Here, we used dissociated neural organoids derived from four cell lines on MEAs to characterise functional synapse development using multiple parameters across time. The dissociated organoids had increasing functional connectivity and network activity over time across all cell lines and plasticity in response to synaptic-like stimulation. Like the organoids they were derived from, dissociated organoid cultures contained a diverse mixture of cell types. Variability in activity parameters was associated with differences in cell type composition and regional identity, which in turn were affected by donor cell line and batch effects. These results demonstrate that dissociated cerebral organoids can generate functional neurons, akin to primary neuronal cultures from brain tissue, providing a scalable model for studies of neurodevelopment and synaptic function.

neuroscience↗

Human-specific morphoregulatory signatures in basal radial glia characterize neocortex evolution

As the seat of our cognition, the human neocortex is an object of immense fascination. Human neocortex expansion during evolution has been attributed to an increase in the proliferative capacity of neural progenitor cells during development, particularly basal radial glia (bRG). Despite their evolutionary relevance, the genomic changes driving human-specific bRG biology remain uncharacterized. We used comparative chromatin and transcriptional profiling of neural progenitor cells isolated from gorilla, chimpanzee and human cerebral organoids to identify cis-regulatory elements that have gained activity in humans. Focusing specifically on bRG, we discovered that morphoregulatory enhancer activity and gene expression signatures distinguish human bRG from other great apes. Functional analysis of the morphoregulatory genes FAM107A and CNGA3 in human organoids revealed that these genes are required for the morphological complexity of human bRG. Taken together, our interspecies comparison of basal radial glia suggests that human-specific morphoregulatory signatures characterize neocortex evolution.

neuroscience↗

Direct-view oblique plane microscopy

The ability to rapidly image mesoscopic samples is critically important for many areas of biological research. Owing to its high through-put and gentle, volumetric imaging nature, light-sheet fluorescence microscopy (LSFM) is an attractive modality to image such samples. However, the orthogonal dual-objective geometry of LSFM makes sample mounting challenging. Oblique plane microscopy (OPM) circumvents these issues by achieving light-sheet imaging through a single objective near the sample, with a further two objectives acting to image a tilted, oblique plane in the specimen. However, at low magnification, as required for mesoscopic imaging, conventional OPM systems suffer from a complicated and inefficient light path and/or a limited numerical aperture. Here we present a simple method for mesoscopic OPM that enables efficient light collection at any numerical aperture. By placing the camera directly in the remote space, the oblique plane can be imaged without the need for a third microscope system. Using a commercially available camera with 1.4 {micro}m pixels, we demonstrate imaging over a 5.3 x 3 x 2.6 mm3 field of view with a lateral resolution of [~]2 {micro}m and axial resolution of [~]22 {micro}m. Our technique is then used to image a 4x-expanded brain organoid.

biophysics↗

Isolation and characterization of synaptic structures from human neural organoids

Human neural organoids (NOs) provide a powerful platform for investigating synaptic development and dysfunction during early neurodevelopment. However, methodologies for isolating functional synaptic structures from these models remain limited. Here, we present a differential centrifugation protocol enabling the enrichment of growth cone particles (GCPs) and immature synaptosomes from air-liquid interface cerebral organoids (ALI-COs) at distinct developmental stages (day 90 and 150). Notably, the method avoids density gradients, requires minimal starting material while maintaining reproducibility across human and murine tissues. Quantitative proteomic profiling revealed significant enrichment of growth cone markers (e.g. GAP43) and classical synaptosomal proteins (e.g. PCLO, BSN, SYN1). Transmission electron microscopy (TEM) confirmed the presence of membrane-enclosed GCPs with fibrous content and mitochondria in day 90 isolates, and immature synaptosomes containing synaptic vesicles on day 150. Functional viability of both types of synaptic structures was demonstrated through KCl-induced depolarization, which triggered phosphorylation changes in growth cone proteins (GAP43, MARCKS, MARCKSL1), cytoskeletal regulators (DCLK1, SHTN1, MARK4, MAP1B) and protein kinases (CAMK2G, PRKCE) in day 90 GCPs, as well as classical synaptic vesicle cycle proteins (SYN1, DNM1, RPH3A) at day 150. Overall, this study establishes a centrifugation-based protocol for isolating growth cones and immature synapses from human organoids, capturing key stages of synaptic development and enabling scalable, patient-compatible models to study synaptic function and dysfunction in neurodevelopmental and neurodegenerative disorders.

neuroscience↗

Epigenetic restoration of differentiation competency via reversal of epiblast regionalisation

Although the epiblast in the embryo has the capacity to generate all tissues of the body, its in vitro counterparts often exhibit differentiation biases, posing significant challenges for both basic research and translational applications involving pluripotent stem cells (PSCs). The origins of these biases remain incompletely understood. In this study, we identify PSC differentiation biases as arising from fluctuations in repressive and activating histone posttranslational modifications, leading to the acquisition of a caudal epiblast-like phenotype. We present a novel approach to overcome this bias using a chemical chromatin restoration (CHR) treatment. This method restores transcriptional programs, chromatin accessibility, histone modification profiles, and differentiation potential, effectively recapitulating the competent anterior epiblast-like state. Furthermore, we propose that a high bivalency state is a defining feature of the anterior human epiblast. We suggest that fluctuations in histone modification marks drive epiblast regionalization, ultimately shaping cellular responses to differentiation cues.

developmental biology↗

Calcium dynamics tune developmental tempo to generate evolutionarily divergent axon tract lengths

The human brain has undergone an evolutionary expansion in size, both in terms of cell numbers and the size of cellular structures, including axon tracts. Human brain development also progresses slowly and takes particularly long. However, the functional relevance of slowed timing, and whether it is responsible for these changes in size, remains unknown. Here, we investigate this by studying axon tract development in human and mouse brain organoids. We demonstrate that human axon tracts grow [~]2x more slowly than those of mice, reflecting their slowed tempo, but that this actually leads to shorter human axons, not longer. To overcome the effect of slowed tempo, human axons have a more prolonged growth duration that enables them to project farther despite their slower growth rate. Using a combination of single-cell RNA sequencing and live imaging, we demonstrate that the prolonged duration involves a different mechanism to that controlling tempo and is driven by calcium dynamics. Human axons exhibit a reduced calcium influx compared to mouse, mediated by L-Type voltage-gated calcium channels. Stimulating this calcium influx in human neurons triggers earlier cessation of growth, leading to shorter axon tracts similar to those of mouse. We further show that increasing calcium speeds up the transition to the synaptogenesis stage. Thus, calcium regulation sets the timing of transitions to disproportionately extend developmental duration, thereby enabling evolutionary expansion of human neurons.

developmental biology↗

Mouse brain organoids model in vivo neurodevelopment and function and capture differences to human

In the last decade since their emergence, brain organoids have offered an increasingly popular and powerful model for the study of early development and disease in humans. These 3D stem cell-derived models exist in a newer space at the intersection of in vivo and 2D in vitro models. Functional benchmarking has so far remained largely uncharacterised however, leaving the extent to which these models may accurately portray in vivo processes still yet to be fully realised. Here we present a standardised unguided protocol to generate brain organoids from mice, the most commonly-used in vivo mammalian model; and in parallel establish a guided protocol for generating region-specific choroid plexus mouse organoids. Both unguided and guided mouse organoids progress through neurodevelopmental stages with an in vivo-like tempo and recapitulate species-specific characteristics of neural and choroid plexus development, respectively. Neuroepithelial cells generate neural progenitors that give rise to different neural subtypes including deep-layer neurons, upper-layer neurons, and glial cells. We further adapted protocols to prolong mouse cerebral organoid (CO) cultures as slices at the air-liquid interface (ALI), enhancing accessibility for long-term studies and functional investigations. In mature mouse ALI-COs, we observed mature glia, as well as synaptic structures and long-range axon tracts projecting to distant regions, suggesting an establishment and maturation of neural circuitry. Indeed, functional analyses with high-density multi-electrode arrays (HD-MEAs) indicate comparable activity to ex vivo organotypic mouse brain slices. Having established protocols for both region-specific and unpatterned mouse brain organoids, we demonstrate that their neurodevelopmental trajectories, and resultant mature features, closely mimic the in vivo models to which they are benchmarked across multiple biochemical, morphological, and functional read-outs. We propose that mouse brain organoids are a valuable model for functional studies, and provide insight into how closely brain organoids of other species, such as human, may recapitulate their own respective in vivo development.

neuroscience↗

Optimizing PSC culture for generating neural organoids

Cerebral organoids generated according to unguided protocols produce neural tissue with exceptional cell diversity and fidelity to in vivo. However, with only minimal extrinsic intervention, the importance of high quality starting material becomes paramount. Better understanding of what constitutes a high quality stem cell line and how to maintain those properties throughout prolonged culture is therefore a crucial foundation for successful organoid differentiation. In this study, we investigate the proteome and phospho-proteome of human pluripotent stem cells to uncover the mechanisms that drive neural organoid competence. We identify aberrant cell-extracellular matrix interaction and increased oxidative metabolism as hallmarks of poor neural differentiators. Drawing on the proteomic data and published literature, we optimise culturing conditions by using improved coating matrix, sustained supply of the key growth factor FGF2 and reducing oxidative stress. These adjustments improve brain organoid generation across all tested cell lines, though with varying degrees of efficiency. This work highlights the importance of optimal culture conditions to best support stem cells, ultimately enhancing the quality of brain organoids produced.

cell biology↗

A minimally guided organoid model for cross-species comparisons of cerebellar development

The human cerebellum has undergone significant evolutionary expansion compared to other species, contributing to both motor and cognitive skills. However, the mechanisms underlying this process remain largely unknown as interrogating human cerebellar development alongside other species has to date been unfeasible. To address this, we developed a minimally guided cerebellar organoid protocol that combines unguided neural induction with precise temporal calibration of posteriorizing morphogens. This approach effectively overrides default telencephalic fate in cerebral organoids and induces stable cerebellar identities. Cerebellar organoids derived from both human and mouse ESCs exhibit species-specific size differences at comparable developmental stages and show robust induction of cerebellar master regulators and progenitor cell types. This model provides a powerful tool for investigating the mechanisms underlying cerebellar development in the context of both evolution and disease.

developmental biology↗

Temporal proteomic and PTMomic atlas of cerebral organoid development

Cerebral organoids (CBOs) are generated from pluripotent stem cells that undergo neuroectoderm specification and neuronal differentiation in three dimensions. The developing neurons in CBOs migrate and self-organize into cerebral cortex-like layers, mimicking human brain development. CBOs develop according to intrinsic signaling mechanisms and offer unique insights into mechanisms of early human brain development. This process requires coordinated spatiotemporal regulation of protein expression and function, where the latter can be achieved by post-translational modifications (PTMs) on proteins. Despite the importance of proteins in brain development and function, profiling of protein abundance and the involvement of PTMs in CBO development remain underexplored. To gain insight into protein and PTM abundance in CBOs, we performed a high-resolution temporal analysis of CBOs up to day 200 using proteomics, PTMomics and metabolomics. We quantified more than 9,300 proteins and various neurodevelopmentally relevant PTMs (including phosphorylation, lysine acetylation, sialylated N-glycosylation, and cysteine modifications). We demonstrate that protein abundance and dynamic PTMs show significant temporal changes during CBO development related to neuronal differentiation and energy metabolism, whereas calcium signaling is mainly regulated by dynamic PTMs. We further show that synaptic protein content correlated with neurotransmitter levels, and we detected astroglia beyond day 100. Lastly, comparative analysis showed proteomic similarities between CBOs and human fetal brain tissue, supporting the physiological relevance of CBOs. Overall, our study presents a temporal atlas of protein and PTM abundance in CBOs and provides a valuable resource for studying neurodevelopment in neural organoids.

neuroscience↗

Circadian clocks in human cerebral organoids

Circadian rhythms result from cell-intrinsic timing mechanisms that impact health and disease1,2. To date, however, neural circadian research has largely focused on the hypothalamic circuitry of nocturnal rodents3. Whether circadian rhythms exist in human brain cells is unknown. Here we show bona fide circadian rhythms in human neurons, glia, cerebral organoids, and cerebral organoid slices (ALI-COs)4-8. Human neural circadian rhythms are synchronised by physiological timing cues such as glucocorticoids and daily temperature cycles, and these rhythms are temperature-compensated across the range of normal human brain temperatures9. Astrocyte rhythms are phase-advanced relative to other cultures and they modulate neuronal clock responses to temperature shift. Cerebral organoid rhythms are more robust at physiological brain temperatures; the relative amplitude of these rhythms increases over time in culture and their resetting capacity recapitulates key neurodevelopmental transitions in glucocorticoid signalling10-14. Remarkably, organoid post-transcriptional bioluminescent clock reporter rhythms are retained even when those of their putative transcriptional drivers are indiscernible15, and electrophysiology recordings confirm circadian rhythms in functional activity of monocultures, organoids, and ALI-COs. Around one third of the cerebral organoid proteome and phosphoproteome are circadian-rhythmic, with temporal consolidation of disease-relevant neural processes. Finally, we show that human brain organoid rhythms can be modulated and disrupted by commonly used brain-permeant drugs and mistimed cortisol exposure, respectively. Our results demonstrate that human brain cells and tissues develop their own circadian oscillations and that canonical mechanisms of the circadian clockwork may be inadequate to explain these rhythmic phenomena. 2D and 3D human neural cultures represent complementary and tractable models for exploring the emergence, disruption, and mechanics of the circadian neural clockwork, with important implications for chronobiology, brain function, and brain health.

neuroscience↗

MEA-NAP compares microscale functional connectivity, topology, and network dynamics in organoid or monolayer neuronal cultures

Microelectrode array (MEA) recordings are commonly used to compare firing and burst rates in neuronal cultures. MEA recordings can also reveal microscale functional connectivity, topology, and network dynamics--patterns seen in brain networks across spatial scales. Network topology is frequently characterized in neuroimaging with graph theoretical metrics. However, few computational tools exist for analyzing microscale functional brain networks from MEA recordings. Here, we present a MATLAB MEA network analysis pipeline (MEA-NAP) for raw voltage time-series acquired from single- or multi-well MEAs. Applications to 3D human cerebral organoids or 2D human-derived or murine cultures reveal differences in network development, including topology, node cartography, and dimensionality. MEA-NAP incorporates multi-unit template-based spike detection, probabilistic thresholding for determining significant functional connections, and normalization techniques for comparing networks. MEA-NAP can identify network-level effects of pharmacologic perturbation and/or disease-causing mutations and, thus, can provide a translational platform for revealing mechanistic insights and screening new therapeutic approaches.

neuroscience↗

Multi-omic analysis of guided and unguided forebrain organoids reveal differences in cellular composition and metabolic profiles

Neural organoids are invaluable model systems for studying neurodevelopment and neurological diseases. For this purpose, reproducible differentiation protocols are needed that minimize inter-organoid variability whilst generating neural organoids that physiologically resemble the brain area of interest. Currently, two main approaches are used: guided, where the differentiation towards neuroectoderm and subsequently specific CNS regions is driven by applying extrinsic signalling molecules, and unguided, where the intrinsic capability of pluripotent stem cells to generate neuroectoderm without external signalling is promoted. Despite the importance for the field, the resulting differences between these models have not been directly investigated. To obtain an unbiased comparison, we performed a multi-omic analysis of forebrain organoids generated using a guided and unguided approach focusing on proteomic, lipidomic and metabolomic differences. Furthermore, we characterised differences in phosphorylation and sialylation states of proteins, two key post-translational modifications (PTMs) in neurodevelopment, and performed single cell transcriptomics (scRNAseq). The multi-omic analysis revealed considerable differences in neuronal-, synaptic and glial content, indicating that guided forebrain organoids contain a larger proportion of neurons, including GABAergic interneurons, and synapses whereas unguided organoids contain significantly more GFAP+ cells and choroid plexus. Furthermore, substantial differences in mitochondrial- and metabolic profiles were identified, pointing to increased levels of oxidative phosphorylation and fatty acid {beta}-oxidation in unguided forebrain organoids and a higher reliance on glycolysis in guided forebrain organoids. Overall, our study comprises a thorough description of the multi-omic differences arising when generating guided and unguided forebrain organoids and provide an important resource for the organoid field studying neurodevelopment and -disease.

neuroscience↗