Biology subjects

Bestard-Cuche, N.

Publications and source records attributed to Bestard-Cuche, N..

5 recordsLinked to original sources

bioRxiv2026

FGF signaling induces disease-associated oligodendrocyte states and drives myelin pathology

Myelin integrity is essential for normal central nervous system (CNS) function and is disrupted in neuroinflammatory and neurodegenerative disorders, including multiple sclerosis and Alzheimer's disease. In these settings, myelin-forming oligodendrocytes adopt a conserved disease-associated transcriptional state, termed disease-associated oligodendrocytes (DAOs). How DAOs arise, the signals that drive their induction, and whether they actively contribute to pathology remain poorly understood. Here we show that FGF signaling instructs mature oligodendrocytes to enter disease-associated states that are sufficient to trigger myelin pathology. By screening disease-linked secreted factors, we identify FGF1 and FGF2 as potent inducers of a DAO-like state in purified oligodendrocyte cultures, characterized by transcriptional reprogramming and myelin-membrane shedding. In vivo, activating oligodendrocyte FGF signaling is sufficient to elicit DAO programs and myelin disruption, whereas inhibiting FGF signaling suppresses DAO induction in a mouse model of multiple sclerosis. Finally, analysis of post-mortem multiple sclerosis tissue reveals a concordant DAO-like state associated with increased engagement of the FGF/FGFR axis. Collectively, these studies define a regulated mechanism of DAO formation linked to myelin disruption and position mature oligodendrocytes as active contributors to myelin pathology in CNS disease.

neuroscience↗

bioRxiv2026

A human developmental and adult brain atlas benchmarks dopaminergic stem cell models and cell therapy candidates

Parkinsons disease (PD) is characterized by the progressive loss of midbrain dopaminergic (mDA) neurons1. Stem cell-derived mDA neurons hold promise for disease modelling2,3 and are currently in clinical trials for cell replacement therapy4-6. However, systematic benchmarking has been limited by the lack of a unified high-resolution reference and methods that quantify incomplete or mixed lineage specification in vitro7. We establish a single-cell and spatial atlas of the human developing diencephalon-midbrain-hindbrain axis resolving 93 cell subtypes, including 39 lacking prior single-cell characterization and 4 entirely novel populations. Using this atlas as a reference, we integrate 19 hPSC-derived mDA datasets, both published2,8-25 and unpublished, to build the Human Dopaminergic Neural Atlas (HDNA) spanning 2D, 3D, and graft models, including those used in clinical trials. To classify cells and quantify lineage fidelity, we develop CapybaraBrain, a marker-driven non-negative decomposition framework that assigns each cell continuous identity scores across all 93 developmental programs, enabling systematic discrimination of discrete, transitioning, and cross-lineage hybrid states26. We uncover a pervasive landscape of off-target populations reflecting relaxed transcriptional boundaries in vitro, including a previously unrecognized TH-PITX2 midbrain neuronal population, and we validate atlas-predicted latent lineage plasticity through inducible genetic fate mapping in mouse models. We further define maturation-associated transcriptional programs by harmonizing adult mDA subtype atlases, revealing that dopaminergic identity and maturation are partially decoupled across protocols. Finally, projecting PD patient-derived tri-cultures onto the HDNA uncovers genotype- and cell-type-specific transcriptional dysregulation. Together, these integrated atlases and computational framework establish a unified standard for benchmarking differentiation fidelity, exposing off-target states, and guiding next-generation PD models and cell therapies.

Developmental Biology↗

bioRxiv2024

Single-nuclei histone modification profiling of the adult human central nervous system unveils epigenetic memory of developmental programs

The adult human central nervous system (CNS) is remarkably complex, with neural cells displaying extensive transcriptional heterogeneity. However, how different layers of epigenetic regulation underpin this heterogeneity is poorly understood. Here, we profile the adult human CNS from distinct regions, for chromatin accessibility at the single-nuclei level. In addition, we simultaneously co-profiled the histone modifications H3K27me3 and H3K27ac at the single nuclei-level, providing their first map in all major human CNS cell types. We unveil primed chromatin signatures at HOX loci in spinal cord-derived human oligodendroglia (OLG) but not microglia. These signatures were reminiscent of developmental OLG but were decoupled from robust gene expression. Moreover, using high-resolution Micro-C, we show that induced pluripotent stem cell (iPS) derived human OLGs exhibit a HOX chromatin architecture compatible with the primed chromatin in adult OLGs, and bears a strong resemblance not only to OLG developmental architecture, but also high-grade pontine gliomas. Thus, adult OLG retain epigenetic memory from developmental states, which might enable them to promptly transcribe Hox genes, in contexts of regeneration, but also make them susceptible to gliomagenesis.

neuroscience↗

bioRxiv2022

Mapping the glial transcriptome in Huntington's disease using snRNAseq: Selective disruption of glial signatures across brain regions

Huntingtons disease (HD) is a severely debilitating, autosomal dominant neurodegenerative disease with a fatal outcome. There is accumulating evidence of a prominent role of glia in the pathology of HD, and we investigated this by conducting single nuclear RNA sequencing (snRNAseq) of human post mortem brain in four differentially affected regions; caudate nucleus, frontal cortex, hippocampus and cerebellum. Across 127,205 nuclei from people with HD, and age/sex matched controls, we found heterogeneity of glia which is altered in HD. We describe prominent changes in the abundance of certain subtypes of astrocytes, microglia, oligodendrocyte precursor cells and oligodendrocytes between HD and control samples, and these differences are widespread across brain regions. Furthermore, we highlight two possible mechanisms that characterise the glial contribution to disease pathology. Firstly, we show that upregulation of molecular chaperones represents a cross-glial signature in HD, which likely reflects an adaptive response to the accumulation of mutant Huntingtin (mHTT). Secondly, we show an oligodendrocyte-specific upregulation of the calmodulin-dependent 3,5-cyclic nucleotide phosphodiesterase 1A (PDE1A) in HD brain compared to controls, which may cause dysfunction of key cellular functions due to the downregulation of the important second messengers cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). Our results support the hypothesis that glia have an important role in the pathology of HD, and show that all types of glia are affected in the disease. As glia are more tractable to treat than neurons, our findings may be of therapeutic relevance.

neuroscience↗

bioRxiv2022

Marked regional glial heterogeneity in the human white matter of the central nervous system

The myelinated white matter tracts of the central nervous system (CNS) are essential for fast transmission of electrical impulses and are commonly affected in neurodegenerative diseases. However, these often uniquely human diseases differentially affect white matter regions, at various ages and between males and females, and we hypothesised that this is secondary to physiological variation in white matter glia with region, age and sex. Using single nucleus RNA sequencing of healthy human post-mortem samples, we find marked glial heterogeneity with tissue region (primary motor cortex, cerebellum, cervical spinal cord), with tissue-specific cell populations of oligodendrocyte precursor cells and astrocytes, and a spinal cord-enriched oligodendrocyte type that appears human-specific. Spinal cord microglia but not astrocytes show a more activated phenotype compared to brain. These regional effects, with additional differentially expressed genes with age and sex in all glial lineages, help explain pathological patterns of disease - essential knowledge for therapeutic strategies.

neuroscience↗