Biology subjects

Iannielli, A.

Publications and source records attributed to Iannielli, A..

5 recordsLinked to original sources

bioRxiv2025

Fully Human Stem Cell-Derived BBB Model for Clinical Disease Modeling and Neurotropic AAV selection

The blood-brain barrier (BBB) is a highly functionalized vascular interface which regulates the exchange of substances between the neural parenchyma and its periphery. BBB leakage, leading to its uncontrolled permeability, is increasingly recognized to facilitate the onset of neuropathologies and aggravate their clinical progression. In vitro models of the BBB have rapidly evolved into elaborated structures that mimic its spatial architecture and multicellular nature. However, their cellular components are currently highly heterogeneous in origin and maturation state. Here, we have developed novel procedures to establish reproducible and scalable sources of endothelial, mural and astroglial cells generating a fully human pluripotent stem cell (hPSC)-derived BBB model, termed thBBBA. hPSC-derived BBB cell types are readily assembled into thBBBAs that develop mature functional properties with high barrier impermeability. Mature thBBBAs can also be generated by frozen hPSC-derived cell samples, providing a simple and scalable off-the-shelf system for general use. thBBBAs were instrumental in identifying the critical pathological role of an IL-6 autocrine source in disrupting thBBBA integrity, increasing its permeability to NMDAR antibodies from autoimmune encephalitis patients, and revealing the therapeutic effects of tocilizumab in this setting. Additionally, we have shown that thBBBAs are an invaluable system for ranking the clinical readiness of novel engineered AAV neurotropic capsids, previously selected in animal models or in vitro systems.

neuroscience↗

bioRxiv2025

Targeted and efficient AAV therapy for neuroblastoma via direct capsid-antibody coupling

Adeno-associated viral (AAV) vectors are widely used in gene therapy for their versatility and safety, but their broad tropism limits cell-specific applications such as targeting primary or metastatic tumor cells. To address this, we developed AAV-STITCH, a strategy using SpyTag technology to covalently attach polypeptides to the AAV capsid. This allows precise, dose-dependent coupling of an anti-GD2 ScFv to a galactose-binding-deficient AAV9-W503A capsid, redirecting tropism specifically to GD2-expressing neuroblastoma (NB) cells. In pseudometastatic xenograft mouse models, AAV-STITCHGD2 selectively transduced NB tumor cells without transduction of healthy tissues. Furthermore, delivery of a suicide gene via AAV-STITCHGD2 suppressed tumor growth and extended survival in mice with subcutaneous and pseudometastatic NB xenografts. These findings establish the feasibility of engineering AAVs with cell-type-specific transduction properties, providing a powerful and adaptable platform for the selective elimination of NB tumor cells. This technology marks a meaningful advance toward next-generation, targeted cancer therapies with strong clinical potential.

bioengineering↗

bioRxiv2023

New AAV9 engineered variants with enhanced neurotropism and reduced liver off-targeting in mice and marmosets

Adeno-Associated Virus 9 (AAV9) is a delivery platform highly exploited to develop gene-based treatments for neurological disorders given its low pathogenicity and brain tissue tropism. However, the efficacy of this vector is dampened by its relatively low efficiency to cross the adult blood-brain barrier (BBB) and inherent targeting to the liver upon intravenous delivery. We generated a new peptide display library starting from a galactose binding-deficient AAV9 capsid and selected two new AAV9 engineered capsids, named AAV-Se1 and AAV-Se2, with an enhanced targeting in mouse and marmoset brains after intravenous delivery. Interestingly, the loss of the galactose binding strongly reduced the undesired targeting to peripheral organs, and above all liver, while not compromising the transduction of the brain vasculature. However, we had to reconstitute the galactose binding in order to efficiently infect non-endothelial brain cells. Thus, the combinatorial actions of the galactose-binding domain and the installed exogenous displayed peptide are crucial to enhance BBB crossing together with brain cell transduction. We also identified Ly6C1 as primary receptor for AAV-Se2 which is a Ly6A homologue highly expressed in the brain endothelial cells. This study describes a new strategy to select neurotropic AAV9 variants and identifies two novel capsids with high brain endothelial infectivity and extremely low liver targeting based on manipulating the AAV9 galactose binding domain.

bioengineering↗

bioRxiv2022

MCT1-dependent energetic failure and neuroinflammation underlie optic nerve degeneration in Wolfram syndrome mice

Wolfram syndrome 1 (WS1) is a rare genetic disorder caused by mutations in the WFS1 gene leading to a wide spectrum of clinical dysfunctions, among which blindness, diabetes and neurological deficits are the most prominent. WFS1 encodes for the endoplasmic reticulum (ER) resident transmembrane protein Wolframin with multiple functions in ER processes. However, the WFS1-dependent etiopathology in retinal cells is unknown. Herein, we showed that Wfs1 mutant mice developed early retinal electrophysiological impairments followed by marked visual loss. Interestingly, axons and myelin disruption in the optic nerve preceded the degeneration of the retinal ganglion cell bodies in the retina. Transcriptomics at pre-degenerative stage revealed the STAT3-dependent activation of proinflammatory glial markers with reduction of the homeostatic and pro-survival factors Glutamine synthetase and BDNF. Furthermore, label-free comparative proteomics identified a significant reduction of the monocarboxylate transport isoform 1 (MCT1) and its partner Basigin that are highly enriched on retinal astrocytes and myelin-forming oligodendrocytes in optic nerve together with Wolframin. Loss of MCT1 caused a failure in lactate transfer from glial to neuronal cell bodies and axons leading to a chronic hypometabolic state. Thus, this bioenergetic impairment is occurring concurrently both in the axonal regions and cell bodies of the retinal ganglion cells, selectively endangering their survival while impacting less on other retinal cells. This metabolic dysfunction occurs months before the frank RGC degeneration suggesting an extended time window for intervening with new therapeutic strategies focused on boosting retinal and optic nerve bioenergetics in WS1.

neuroscience↗

bioRxiv2019

Whole brain delivery of an instability-prone Mecp2 transgene improves behavioral and molecular pathological defects in mouse models of Rett syndrome

Rett syndrome (RTT) is an incurable neurodevelopmental disorder caused by mutations in the gene encoding for methyl-CpG binding-protein 2 (MeCP2). Gene therapy for this disease presents inherent hurdles since MECP2 is expressed throughout the brain and its duplication leads to severe neurological conditions as well. However, the recent introduction of AAV-PHP.eB, an engineered capsid with an unprecedented efficiency in crossing the blood-brain barrier upon intravenous injection, has provided an invaluable vehicle for gene transfer in the mouse nervous system. Herein, we use AAV-PHP.eB to deliver an instability-prone Mecp2 (iMecp2) transgene cassette which, increasing RNA destabilization and inefficient protein translation of the viral Mecp2 transgene, limits supraphysiological Mecp2 protein levels in transduced neural tissues. Intravenous injections of the PHP.eB-iMecp2 virus in symptomatic male and female Mecp2 mutant mice significantly ameliorated the disease progression with improved locomotor activity, coordination, lifespan and normalization of altered gene expression and mTOR signaling. Remarkably, PHP.eB-iMecp2 administration did not result in severe toxicity effects either in female Mecp2 mutant or in wild-type animals. In contrast, we observed a strong immune response to the transgene in treated male Mecp2 mutant mice that was overcome by immunosuppression. Overall, PHP.eB-mediated delivery of the iMecp2 cassette provided widespread and efficient gene transfer maintaining physiological Mecp2 protein levels in the brain. This combination defines a novel viral system with significant therapeutic efficacy and increased safety which can contribute to overcome the hurdles that are delaying clinical applications of gene therapy for RTT.\n\nOne Sentence SummaryGlobal brain transduction of the instability-prone Mecp2 transgene by systemic AAV-PHP.eB administration is both safe and effective in protecting male and female Mecp2 mutant mice from the RTT disease phenotype.

neuroscience↗