Biology subjects

Cepeda-Prado, E.

Publications and source records attributed to Cepeda-Prado, E..

3 recordsLinked to original sources

bioRxiv2024

Generating human parvalbumin interneurons through 3D glia reprogramming

Parvalbumin (PV) interneurons are crucial for synaptic plasticity, and their damage or loss is linked to various neurological disorders. Yet, generating these cells of human source in vitro is challenging, limiting advancements in cell repair and disease modelling. We introduce a novel approach to derive human PV neurons through direct reprogramming of glial precursor cells (GPCs). Using ectopic expression of GABAergic neuronal genes, GPCs efficiently convert into GABAergic interneurons in 3D culture environment within weeks and achieve functional neuronal maturity. Single-nuclei RNA sequencing identified a distinct PV neuronal cluster with high maturity and characteristics of PV chandelier subclass that are equivalent to bona fide human interneurons. Trajectory analysis revealed a distinct glia-to-PV interneuron conversion pathway, involving several new transitory genes, with potential for functional importance for PV derivation. Our data introduces a new strategy for generating human PV interneurons, promising significant implications for future generation of patient-specific PV neurons both in vitro and in vivo. HighlightsO_LIA novel approach to derive human PV interneurons by direct glia reprogramming. C_LIO_LIFirst comprehensive transcriptomic profiling of induced human PV interneurons. C_LIO_LIInduced PV interneurons are of chandelier subtype with transcriptional similarity to bona fide interneurons. C_LIO_LISuccessful glia-to-PV interneuron conversion passes through a specific reprogramming trajectory and involves key genes with functional potential. C_LI

neuroscience↗

bioRxiv2023

Injectable 3D microcultures enable intracerebral transplantation of mature neurons directly reprogrammed from patient fibroblasts

Direct reprogramming of somatic cells into induced neurons (iNs) has become an attractive strategy for the generation of patient-specific neurons for disease modeling and regenerative neuroscience. To this end, adult human dermal fibroblasts (hDFs) present one of the most relevant cell sources. However, iNs generated from adult hDFs using two-dimensional (2D) cultures poorly survive transplantation into the adult brain in part due to the need for enzymatic or mechanical cellular dissociation before transplantation. Three-dimensional (3D) culturing methodologies have the potential to overcome these issues but have largely been unexplored for the purposes of direct neuronal reprogramming. Here we report a strategy for direct in vitro reprogramming of adult hDFs inside suspension 3D microculture arrays into induced DA neurospheroids (iDANoids). We show that iDANoids express neuronal and DA markers and are capable of firing mature action potentials and releasing dopamine. Importantly, they can be gently harvested and transplanted into the brain of a Parkinsons disease rat model to reproducibly generate functionally integrated neuron-rich grafts. The 3D culturing approach presented here thus eliminates a major bottleneck in direct neuronal reprogramming field and, due to its simplicity and versatility, could readily be adapted as a culturing platform used for a broad range of transplantation studies as well as disease modeling.

neuroscience↗

bioRxiv2023

Label-free high-resolution infrared spectroscopy for spatiotemporal analysis of complex living systems

Label-free chemical and structural imaging of complex living tissue and biological systems is the holy grail of biomedical research and clinical diagnostics. The current analysis techniques are time-consuming and/or require extensive sample preparation, often due to the presence of interfering molecules such as water, making them unsuitable for the analysis of such systems. Here, we demonstrate a proof-of-principle study using label-free optical photothermal mid-infrared microspectroscopy (O-PTIR) for fast, direct spatiotemporal chemical analysis of complex living biological systems at submicron resolution. While other analytical methods can provide only static snapshots of molecular structures, our O-PTIR approach enables time-resolved and in situ investigation of chemical and structural changes of diverse biomolecules in their native conditions. This comprises a technological breakthrough in infrared spectroscopy to analyze biomolecules under native conditions over time: in fresh unprocessed biopsies, living brain tissue, and vertebrates without compromising their viability. One-Sentence SummaryProof-of-principle application of non-destructive O-PTIR for high-resolution spatiotemporal chemical and structural analysis of unprocessed biopsies, living brain tissue, and vertebrates.

molecular biology↗