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Tedesco, F. S.

Publications and source records attributed to Tedesco, F. S..

8 recordsLinked to original sources

NAD+ limitation and α-ketoglutarate depletion define cancer induced muscle atrophy

Tumour-host crosstalk is an emerging hallmark of malignancy. It is increasingly recognised that cancer alters non-tumour bearing distant organs, with important consequences for disease progression and survival. Skeletal muscle loss, a defining feature of cancer-associated cachexia, contributes to morbidity and reduced quality of life, yet its underlying mechanisms remain poorly understood. In this study we analysed the secretome of pancreatic cancer cells and identified a metabolite-driven signal that induces myotube atrophy. Our data suggests that atrophy, which seems to involve cytoskeletal stress and increased myosin contractility, arises from cancer cell-dependent reductive metabolic rewiring. Pancreatic cancer cells conditioned their environment with elevated levels of lactate, generating a lactate-rich extracellular milieu that decrease the NAD+/NADH ratio in myotubes. This redox imbalance impaired oxidative metabolism, decreasing -ketoglutarate (KG) levels and disrupted KG-dependent processes. Restoration of NAD+ or KG levels rescued myotube atrophy. Skeletal muscle from cancer-associated cachexia mouse models exhibited reduced KG levels. Collectively, these findings identify a targetable metabolite-mediated mechanism of tumour-muscle crosstalk.

cancer biology↗

A Single Lipid Nanoparticle Formulation Enables Delivery of Diverse RNA Therapeutics to Human Muscle Models of Duchenne Muscular Dystrophy

Duchenne muscular dystrophy is a lethal neuromuscular disorder caused by the absence of dystrophin, for which no curative treatment is available. RNA-based approaches have shown promising results; however, their evaluation is hindered by the lack of robust and rapid delivery methods for differentiated human muscle cells, which represent the most physiologically relevant in vitro models for assessing therapeutic strategies. Here, we establish a versatile lipid nanoparticle platform enabling efficient delivery of diverse RNA therapeutics across a range of human muscle models, including myotubes, induced pluripotent stem cell-derived myotubes, myoblasts, cardiomyocytes, and 3D engineered skeletal muscle tissues. Remarkably, a single commercially available lipid nanoparticle formulation supports delivery of cargos spanning more than 300-fold in size, from short antisense oligonucleotides ([~]20 nt) to complex CRISPR-based editors (up to [~]6.7 kb), including Cas9 nucleases, adenine base editors, and CRISPRa systems. This enables efficient gene correction and transcriptional modulation, resulting in dystrophin restoration or compensatory utrophin upregulation in relevant Duchenne muscular dystrophy models. Together, our results establish a single lipid nanoparticle formulation as a versatile platform for RNA delivery in human muscle systems and provide a practical framework for the rapid preclinical assessment of emerging therapies for Duchenne muscular dystrophy and other neuromuscular disorders. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=92 SRC="FIGDIR/small/741396v1_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@a18d71org.highwire.dtl.DTLVardef@4d0faforg.highwire.dtl.DTLVardef@140b078org.highwire.dtl.DTLVardef@1a235_HPS_FORMAT_FIGEXP M_FIG C_FIG Created in BioRender. Leclerc, D. (2026) https://BioRender.com/90h0fme

molecular biology↗

Advanced human iPSC-based modelling of LMNA-related congenital muscular dystrophy enables development of targeted genetic therapies for muscle laminopathies

LMNA-related congenital muscular dystrophy (L-CMD) is amongst the most severe forms of laminopathies, which are diseases caused by pathogenic variants in the LMNA gene. LMNA encodes the proteins Lamin A and C, which assemble with Lamin B1 and B2 to form the nuclear lamina: a meshwork providing structural stability to the nucleus that also regulates chromatin organisation and gene expression. Research into L-CMD mechanisms and therapies is hindered by lack of humanised, tissue-specific models that accurately recapitulate disease phenotypes. We previously reported that LMNA-mutant induced pluripotent stem cell (iPSC)-derived skeletal muscle cells have nuclear shape abnormalities and Lamin A/C protein mislocalisation. Here, we expand the selection of L-CMD patient- derived iPSCs and validate disease-associated readouts using a transgene-free based protocol which more accurately mimics skeletal myogenesis. Results showed no overt defects in developmental myogenesis, but recapitulation of pathological nuclear shape abnormalities in 2D and 3D cultures, nuclear envelope protein mislocalisation and transcriptomic alterations across multiple pathogenic LMNA variants. We then utilised this platform to assess LMNA gene editing strategies. CRISPR-based exon removal generated stable RNA and protein Lamin A/C species, without significant normalisation of nuclear morphological phenotypes or transcriptomic profile. Conversely, precise editing of the same mutation showed complete reversal of disease-associated nuclear morphometrics, alongside normalisation of the pro-inflammatory transcriptomic signature. Our data provide the foundation for a humanised in vitro disease and therapy modelling platform for this complex and severe muscle disorder. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=81 SRC="FIGDIR/small/660928v2_ufig1.gif" ALT="Figure 1"> View larger version (15K): org.highwire.dtl.DTLVardef@134276forg.highwire.dtl.DTLVardef@108f44forg.highwire.dtl.DTLVardef@dfa04eorg.highwire.dtl.DTLVardef@1956a90_HPS_FORMAT_FIGEXP M_FIG C_FIG HIGHLIGHTSO_LILMNA-mutant iPSCs undergo efficient skeletal myogenesis upon transgene-free, small molecule-based lineage-directed differentiation C_LIO_LIL-CMD iPSCs recapitulate hallmark disease-associated nuclear phenotypes and show a pro-inflammatory transcriptional profile C_LIO_LIDisease modelling platforms based on iPSC-derived skeletal muscle cells enable comparative testing of gene editing strategies C_LIO_LICRISPR-edited L-CMD iPSC-derived myogenic cells show amelioration of disease-associated readouts C_LI

cell biology↗

VISIBLE: An imaging-driven system for sampling, biofabrication, and manipulation of complex biological models

Complex in vitro models (CIVMs), including organoids, spheroids, and bioprinted constructs, have emerged as powerful platforms for recapitulating human tissue architecture and function. However, their inherent heterogeneity and dynamic nature pose significant challenges for standardization, reproducibility, and real-time manipulation. Here, we present VISIBLE (Versatile Imaging-Based Interactive Sampling and Bioprinting System), a modular, imaging-guided platform that integrates real-time monitoring with automated manipulation and 3D bioprinting that addresses these challenges. VISIBLE employs a dual-axis system comprising independently controlled tool-heads and microscope stages, enabling precise spatiotemporal interventions within live cultures. We demonstrate the system capabilities across a range of applications, including morphology- and function-based sampling of organoids and neurospheres, interactive 3D bioprinting, serial scratch assays, and real-time cell-cell interaction studies. Furthermore, we illustrate the system utility in translational contexts through the selective sampling and implantation of patient-derived xenograft organoids. VISIBLE supports long-term culture within an integrated incubation environment and accommodates interchangeable tool-heads for scalable, high-throughput workflows. By enabling closed-loop, feedback-controlled experimentation, VISIBLE addresses some of the critical limitations in existing CIVM platforms and offers a new versatile solution for a wide range of biomedical research applications. This work represents a significant step toward the development of autonomous experimental systems for complex tissue modelling and preclinical investigation.

bioengineering↗

Metabolic remodelling in hiPSC-derived myofibres carrying the m.3243A>G mutation

Mutations in mitochondrial DNA cause severe multisystem disease, frequently associated with muscle weakness. The m.3243A>G mutation is the major cause of Mitochondrial Encephalomyopathy Lactic Acidosis and Stroke Like episodes (MELAS). Experimental models that recapitulate the disease phenotype in vitro for disease modelling or drug screening are very limited. We have therefore generated hiPSC-derived muscle fibres with variable heteroplasmic mtDNA mutation load without significantly affecting muscle differentiation potential. The cells are excitable and show physiological characteristics of muscle fibres and show well organised myofibrillar structure. In cells carrying the m.3243A>G, the mitochondrial membrane potential and oxygen consumption were reduced in relation to the mutant load. We have shown through proteomic, phosphoproteomic, and metabolomic analyses that the m.3243A>G mutation variably affects the cell phenotype in relation to the mutant load. This variation is reflected by an increase in the NADH/NAD+ ratio, which in turns influences key nutrient-sensing pathways in the myofibres. This model enables detailed study of the impact of the mutation on cellular bioenergetics and on muscle physiology with the potential to provide a platform for drug screening.

cell biology↗

CRISPR-Cas9 mediated endogenous utrophin upregulation improves Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is a lethal neuromuscular disorder caused by loss of dystrophin. Upregulation of utrophin (UTRN), a dystrophin paralogue, is a promising therapeutic avenue. Here, we present a CRISPR-Cas9-mediated strategy to increase utrophin expression by disrupting microRNA (miR) binding sites (BS). Using a Cas9/gRNA ribonucleoprotein (RNP) complex we disrupted several miR BS in DMD myoblasts and selected the Let-7c BS has crucial for UTRN repression. Interestingly, Cas9/gRNA indels were as efficient as the complete removal of Let-7c BS in upregulating UTRN expression, without any major off-targets. In three-dimensional human DMD cultures, Cas9/gRNA-mediated editing resulted in significant utrophin upregulation and functional improvements of calcium dysregulation and muscle contraction. Finally, Let-7c BS disruption in mdx animals by systemic rAAVs mediated delivery of Cas9 and gRNA resulted in utrophin upregulation and amelioration of the muscle histopathological phenotype. These findings provide the foundations for a universal (mutation-independent) gene editing therapeutic strategy for DMD. One Sentence SummaryCRISPR-Cas9 has the potential to upregulate utrophin to treat all DMD patients.

molecular biology↗

Combining SLA 3D printing and soft lithography for fast, versatile, and accessible high-resolution fabrication of customised multiscale cell culture devices with complex designs

Cell culture devices, such as microwells and microfluidic chips, are designed to increase the complexity of cell-based models whilst retaining control over culture conditions and have become indispensable platforms for biological systems modelling. From microtopography, microwells, plating devices and microfluidic systems to larger constructs for specific applications such as live imaging chamber slides, a wide variety of culture devices with different geometries have become indispensable in biology laboratories. However, while their application in biological projects is increasing exponentially, due to a combination of the techniques and tools required for their manufacture, and the physical science background sometimes needed, the design and fabrication of such devices directly by biological labs remains a relatively high investment in terms of costs, use of facilities, needed collaborations and time. Whilst commercially available systems are available, these are also often costly, and importantly lack the potential for customisation by each single lab. This combination of factors still limits widespread application of microfabricated custom devices in most biological wet labs. Capitalising on recent important advancements in the fields of bioengineering and microfabrication, and taking advantage of low-cost, high-resolution desktop resin 3D printers combined with PDMS soft lithography, we have developed an optimised low-cost and highly reproducible microfabrication pipeline, capable of generating a wide variety of customisable devices for cell culture and tissue engineering in an easy, fast reproducible way for a fraction of the cost of conventional microfabrication or commercial alternatives. This protocol is designed specifically to be a resource for biological labs with little to none prior exposure to these fields technique and enables the manufacture of complex devices across the {micro}m to cm scale. We provide a ready-to-go pipeline for the efficient treatment of resin-based 3D printed constructs for PDMS curing, using a combination of curing steps, washes and surface treatments. Together with the extensive characterisation of the fabrication pipeline, we show the utilization of this system to a variety of applications and use cases relevant to biological experiments, ranging from micro topographies for cell alignments to complex multi-part hydrogel culturing systems. This methodology can be easily adopted by any wet lab, irrespective of prior expertise or resource availability and will enable the wide adoption of tailored microfabricated devices across many fields of biology.

bioengineering↗

DLL4 and PDGF-BB regulate migration of human iPSC-derived skeletal myogenic progenitors

Muscle satellite stem cells (MuSCs) are responsible for skeletal muscle growth and regeneration. Despite their differentiation potential, human MuSCs have limited in vitro expansion and in vivo migration capacity, limiting their use in cell therapies for diseases affecting multiple skeletal muscle groups such as muscular dystrophies. Several protocols have been developed to derive progenitor cells similar to MuSCs from human induced pluripotent stem cells (hiPSCs), in order to establish a source of myogenic cells with controllable proliferation and differentiation capacity. However, currently available hiPSC myogenic derivatives also suffer from limitations of cell migration, ultimately delaying their clinical translation. Here we provide evidence that activation of NOTCH and PDGF pathways with DLL4 and PDGF-BB improves migration of hiPSC-derived myogenic progenitors in vitro. Transcriptomic and functional analyses demonstrate that this property is conserved across species and multiple hiPSC lines, including genetically-corrected hiPSC derivatives from a patient with Duchenne muscular dystrophy. DLL4 and PDGF-BB treatment had no negative impact on cell proliferation; cells maintained their myogenic memory, with differentiation fully rescued by NOTCH inhibition. RNAseq analysis indicate that pathways involved in cell migration are modulated in treated myogenic progenitors, consistent with results from functional profiling of cell motility at single cell resolution. Notably, treated cells also showed enhanced trans-endothelial migration in transwell assays. Enhancing extravasation is a key translational milestone for intravascular delivery of hiPSC myogenic derivatives: our study establishes the foundations of a transgene-free, developmentally inspired strategy to achieve this goal, moving hiPSCs one step closer to future muscle gene and cell therapies.

cell biology↗