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Corigliano, M. R.

Publications and source records attributed to Corigliano, M. R..

4 recordsLinked to original sources

Noninvasive Focal Gene Delivery of Functional Neural Actuators to the Primate Spinal Cord using Focused Ultrasound

Pathologies of the spinal cord -- from degenerative diseases to chronic pain -- represent a substantial global health burden. Although surgical and pharmacological treatments for spinal cord pathologies have advanced considerably, therapies capable of addressing the cellular mechanisms underlying these conditions remain limited. Viral gene therapies present a compelling alternative, allowing for delivery of therapeutic genes that directly target the pathological processes in specific cell-types. Effective viral delivery to the spinal cord, however, remains constrained by a fundamental tradeoff between procedural invasiveness and spatial precision. As such, there remains a need for clinically tractable methods -- that are both noninvasive and focal -- to deliver gene therapeutics across the restrictive vascular boundaries of the blood-spinal cord barrier (BSCB). Here, we demonstrate noninvasive, focal disruption of the BSCB and delivery of systemically administered chemogenetic gene payloads to the cervical and thoracic spinal cord in marmoset nonhuman primates (Callithrix jacchus) using focused ultrasound (FUS). Through systematic testing of ultrasonic pressures and central frequencies, we establish a FUS parameter set optimized for robust, spatially constrained molecular delivery across the marmoset BSCB. Using these optimized parameters, we show that FUS BSCB disruption permitted focal penetrance of systemically administered viral vectors for transduction of both fluorescent transgenes and excitatory chemogenetics within targeted spinal segments. Positron emission tomography (PET) imaging following chemogenetic actuation revealed significantly increased metabolic demand within the targeted region of the spinal cord, demonstrating in vivo evidence of functional transgene expression. Behavioral and histopathological assessments demonstrated preserved neurological function and tissue integrity, supporting the safety of FUS BSCB disruption and viral delivery in nonhuman primates. To facilitate broad application of this platform for noninvasive delivery of receptor-based gene therapeutics in marmosets, we generated an ultra-high-resolution (74 m) multimodal MRI/CT spinal cord template for precise targeting and anatomical localization. We also provide open-access engineering drawings and CAD files for our M-FRAME system (Marmoset Fixation and Reorientation Apparatus for Multimodal Experiments), enabling precise and repeatable spinal targeting without surgical fixation. Together, these results establish FUS-mediated BSCB disruption as a safe and effective approach for noninvasive, focal gene delivery to the primate spinal cord.

neuroscience↗

Noninvasive focal gene transfer of chemogenetic proteins in the primate brain

The development of chemogenetic neuromodulators, including Designer Receptors Exclusively Activated by Designer Drugs (DREADDs), have enabled focally specific, long-lasting, and reversible neuromodulation in the primate brain. Although systemically delivered synthetic ligands allow for noninvasive actuation of chemogenetic receptors, direct intraparenchymal injection remains atop the available methods to precisely deliver chemogenetic payloads to a specific target of the brain. The requirement of trephination, however, is accompanied by inherent risks of infection, long recovery times, and often tissue damage with concomitant behavioral complications. When considering therapeutic injections, the requirement of transcranial surgery does not translate well to the clinic, especially when repeated administrations are required. Here, we leverage our recent development of transcranial focused ultrasound (tFUS) for noninvasive and focal delivery of adeno-associated viruses (AAVs) carrying excitatory Gq-DREADDs to frontal cortical targets (areas 6DR and 8aD) in the marmoset brain. Using [18F]-fluorodeoxyglucose (FDG) positron emission tomography, we demonstrate significant increases in glucose metabolism at the site of viral delivery after administering the DREADD-specific agonist deschloroclozapine (DCZ), as compared to vehicle control. Focal neuronal DREADD expression was confirmed by immunohistochemistry at the site of opening. Through comparison of awake resting-state functional connectivity (whole brain connectivity with the sites of delivery) and structural connectivity (directly injected viral neuronal tracing at the sites of delivery) we demonstrate that the increase in glucose metabolism occurs at both mono- and polysynaptically connected brain regions. Taken together, these results demonstrate the ability to focally deliver excitatory chemogenetics without the need for surgery, allowing for activation of long-range frontal cortex circuits of the primate brain.

neuroscience↗

An Open Access Resource for Marmoset Neuroscientific Apparatus

The use of the common marmoset (Callithrix jacchus) for neuroscientific inquiry has grown precipitously over the past two decades. Despite windfalls of grant support from funding initiatives in North America, Europe, and Asia to model human brain diseases in the marmoset, marmoset- specific apparatus are of sparse availability from commercial vendors and thus are often developed and reside within individual laboratories. Through our collective research efforts, we have designed and vetted myriad designs for awake or anesthetized magnetic resonance imaging (MRI), positron emission tomography (PET), computed tomography (CT), as well as focused ultrasound (FUS), electrophysiology, optical imaging, surgery, and behavior in marmosets across the age- span. This resource makes these designs openly available, reducing the burden of de novo development across the marmoset field. The computer-aided-design (CAD) files are publicly available through the Marmoset Brain Connectome (MBC) resource (https://www.marmosetbrainconnectome.org/apparatus/) and include dozens of downloadable CAD assemblies, software and online calculators for marmoset neuroscience. In addition, we make available a variety of vetted touchscreen and task-based fMRI code and stimuli. Here, we highlight the online interface and the development and validation of a few yet unpublished resources: Software to automatically extract the head morphology of a marmoset from a CT and produce a 3D printable helmet for awake neuroimaging, and the design and validation of 8-channel and 14- channel receive arrays for imaging deep structures during anatomical and functional MRI.

bioengineering↗

Chronic Changes In Oligodendrocyte Sub-Populations After Middle Cerebral Artery Occlusion in Neonatal Mice.

BackgroundNeonatal stroke is common and causes life-long motor and cognitive sequelae. Because neonates with stroke are not diagnosed until days-months after the injury, chronic targets for repair are needed. We evaluated oligodendrocyte maturity and myelination and assessed oligodendrocyte gene expression changes using single cell RNA sequencing (scRNA seq) at chronic timepoints in a mouse model of neonatal arterial ischemic stroke. MethodsMice underwent sixty minutes of transient right middle cerebral artery occlusion (MCAO) on postnatal day 10 (p10) and received 5-ethynyl-2-deoxyuridine (EdU) on post-MCAO days 3-7 to label dividing cells. Animals were sacrificed 14 and 28-30 days post-MCAO for immunohistochemistry and electron microscopy. Oligodendrocytes were isolated from striatum 14 days post-MCAO for scRNA seq and differential gene expression analysis. ResultsThe density of Olig2+EdU+ cells was significantly increased in ipsilateral striatum 14 days post-MCAO and the majority of oligodendrocytes were immature. Density of Olig2+EdU+ cells declined significantly between 14 and 28 days post-MCAO without a concurrent increase in mature Olig2+EdU+ cells. By 28 days post-MCAO there were significantly fewer myelinated axons in ipsilateral striatum. scRNA seq identified a cluster of "disease associated oligodendrocytes (DOLs)" specific to the ischemic striatum, with increased expression of MHC class I genes. Gene ontology analysis suggested decreased enrichment of pathways involved in myelin production in the reactive cluster. ConclusionsOligodendrocytes proliferate 3-7 days post-MCAO and persist at 14 days, but fail to mature by 28 days. MCAO induces a subset of oligodendrocytes with reactive phenotype, which may be a therapeutic target to promote white matter repair.

neuroscience↗