injury

Optimizing CD45-Targeted Astatine-211-Radioimmunotherapy for Malignant and Non-Malignant Blood Disorders

ABSTRACT CD45 is expressed on almost all normal and neoplastic hematopoietic cells but not on non-blood cells and has, therefore, been pursued as a drug target. Initially centered on augmenting conditioning before hematopoietic cell transplantation (HCT) for blood cancers, there is increasing interest in expanding CD45-directed therapies into other settings, with radioimmunotherapy (RIT) being the major therapeutic modality so far. Investigators at our institution pioneered CD45 RIT with b-emitters such as iodine-131 (131I) using the murine monoclonal antibody (mAb), BC8. A phase 3 trial testing 131I-BC8 (131I-apamistamab [Iomab-B]) with allogeneic HCT in older adults with relapsed/refractory acute myeloid leukemia showed improved outcomes over conventional care, validating this approach. More recently, attention has shifted toward a-emitters that deliver substantially higher decay energies over much shorter distances than b-emitters, rendering them more suitable for precise and potent target cell killing. In our work, we focus on astatine-211 (211At) for its ideal half-life and decay without a-emitting daughters. For clinical application, mAbs are conjugated with the bifunctional boron cage molecule, isothiocyantophenethyl-ureido-closo-decaborate(2-) (B10-NCS), to enable stable protein astatination. Three early-phase trials testing 211At-BC8-B10 as augmentation of HCT conditioning for patients with malignant and non-malignant blood disorders are ongoing, with emerging data indicating significant anti-tumor efficacy. Nonetheless, relapses still occur. Other important limitations include marked infusion toxicities and human antimouse antibody (HAMA) responses related to the murine nature of BC8 and dimer formation after 211At labeling of mAb-B10 conjugates with tissue residualization from 211At atom oxidation. The latter may contribute to the risk of liver cell injury, the dose limiting extramedullary toxicity of CD45 RIT. As a first step toward our goal of optimizing CD45 RIT, we have raised new, fully human CD45 mAbs as basis for novel therapeutics. In preliminary in vivo studies in immunodeficient mice, we found some of these mAbs to have greater anti-tumor efficacy than a humanized version of BC8 (HuBC8) we generated as a reference mAb. We will now conduct comparative in vivo CD45+ cell targeting (“biodistribution”) and anti-tumor efficacy studies to select a lead candidate mAb for clinical application and use protein engineering to maximize the selectivity and efficacy of targeted radiation delivery. We will use immunodeficient mice xenotransplanted with human leukemia cells for this purpose as no human approaches are available and in vitro testing is inadequate to measure both the targeting and biologic RIT effects on human leukemia cells. Mice provide the in vivo milieu needed for comprehensive evaluation. Development of improved mAb astatination methodologies to minimize off-target toxicities of 211At-RIT will further increase therapy specificity and reduce toxicity. In parallel, we will conduct genome-scale, unbiased target identification/validation studies to identify partner drugs for rational combination therapies aimed at enhancing the anti-tumor efficacy of 211At-CD45 RIT.

Regulation of neutrophil endoplasmic reticulum stress response by IRE1a

Project Summary/Abstract: The lungs are exposed to pathogens and environmental toxins that trigger stress and cause numerous respiratory diseases. Effective host defenses against lung infection by bacterial pathogens, including methicillin- resistant Staphylococcus aureus (MRSA), rely on innate immune cells including neutrophils, prominent early responders to sites of infection. If host defenses are ineffective, MRSA causes serious lung infection, resulting in severe morbidity and a significant economic burden on healthcare facilities, where it is endemic. MRSA infections have a mortality rate of up to 14% and an estimated $500 million in healthcare costs in the US alone. Increasing resistance to vancomycin, the last resort antibiotic for MRSA infections, underscore the urgent need for innovative treatment approaches. Although directly targeting pathogens with antibiotics has been a successful approach for treating infections, many pathogens, including MRSA, eventually will become resistant to these drugs. As an alternative, immunomodulatory strategies to enhance host defenses, such as those shown to be effective against cancer cells, have the potential for treating drug-resistant pathogen infections. Recently, we showed that the inositol-requiring enzyme 1-α (IRE1α), an endoplasmic reticulum (ER) stress sensor, is required for clearance of MRSA in a murine skin abscess model, where neutrophils are robustly recruited to the site of infection. Further, IRE1α coordinates signaling events upstream of calcium (Ca2+) mobilization, histone citrullination, and production of mitochondrial reactive oxygen species (mitoROS), all of which are important for neutrophil inflammatory responses including the formation of antimicrobial neutrophil extracellular traps (NETs). Because excessive neutrophil activation and NET release can be detrimental to vital organs, it is not clear whether neutrophil IRE1α-mediated stress responses aid or impede the resolution of infection in the lungs. While IRE1α activation has been linked to the development of lung fibrosis through the regulation of alveolar epithelial- to-mesenchymal transition in the context of chronic inflammatory diseases, its role in pulmonary neutrophil defenses is unknown. Thus, there is a gap in our knowledge of how cellular stress responses modulate pulmonary neutrophil defenses and infection outcomes in the lungs. The overarching goal of this proposal is to elucidate the mechanisms by which neutrophil IRE1α signaling influences production of mitoROS and Ca2+ mobilization to drive NET release, injure lungs, and regulate pulmonary host defense against MRSA. We will accomplish the following Aims: (1) Define the molecular mechanisms underlying IRE1α-mediated mitoROS hyperactivation of human and mouse primary neutrophils and excessive NET release, and (2) Elucidate the role of neutrophil IRE1α signaling in excessive NET release, lung injury, and immunity in vivo using a MRSA pneumonia infection mouse model. These studies will yield mechanistic insight into how IRE1α-driven ER stress responses impact pulmonary neutrophil defenses and lung injury revealing potential targets for anti-microbial immunotherapies.

Cartilage targeting exosomes for OA gene therapy and pain treatment

Project Summary Gene therapy has the potential to facilitate targeted expression of therapeutic proteins to promote cartilage regeneration in osteoarthritis (OA). The dense, avascular, aggrecan-glycosaminoglycan rich negatively charged cartilage, however, hinders their transport to reach chondrocytes in effective doses. While viral vector mediated gene delivery has shown promise, concerns over immunogenicity and tumorigenic side-effects persist. To address this, we have developed surface-modified cartilage-targeting MSC exosomes as non-viral carriers for gene therapy. MSC derived exosomes have intrinsic therapeutic potential as they can induce cartilage repair and are non-immunogenic, making them desirable for gene delivery. We have engineered charge-reversed cationic exosomes by anchoring cartilage targeting optimally charged arginine-rich cationic peptide (CPC) motifs into the anionic exosome bilayer (Exo-CPC) by using buffer pH as a charge-reversal switch. Exo-CPC use charge interactions to penetrate through the full thickness of arthritic cartilage (close to tidemark) and deliver the packaged genetic material cargo to chondrocytes residing in the deep tissue layers while native anionic exosomes cannot. They can also bind within the synovial joint, making them effective for OA pain relief gene therapy. Here we will engineer charge-reversed Exo-CPC for delivery of IL-1RA (receptor antagonist of interleukin-1) mRNA and NaV1.8 (voltage gated sodium channel 1.8) inhibitor siRNA to stimulate both disease modifying response and long-term pain relief with a one-time intra-articular dose. IL-1RA mRNA targets are in the chondrocytes and synovium cells; Nav1.8 expressing nerves innervate into synovium and subchondral bone in OA – sites that Exo-CPC can readily target. Aim 1 will engineer cartilage targeting Exo-CPC for delivery of IL- 1RA mRNA and Nav1.8 inhibitor siRNA. Their ability to deliver IL-1RA mRNA to chondrocytes and IL-1RA protein translation efficiency will be evaluated in-vitro. Exo-CPC-Na v1.8’s ability to reduce NaV1.8 bioactivity of sensory nerves will also be evaluated. In Aim 2, their distribution intra-articular (proximity to NaV1.8-positive nerves), extra-articular, and DRG and spinal cord using partial meniscectomy NaV1.8-tdTomato reporter mice OA models will be evaluated. Additionally, their dose dependent reduction on MMP activity, neuronal excitability and pain- related behaviors, and any immunogenicity will be assessed. Aim 3 will use the determined functional doses to study the long-term disease modifying and pain-relief effects of mono and combination therapy with Exo-CPC- IL-1RA and Exo-CPC-Nav1.8 in rescuing injury induced tissue structural damage as well as in reducing pain (weight bearing asymmetry) for up to one month following IA administration in early vs. late stages (intervention at 2 vs 6 weeks) of MMT (medial meniscectomy) induced OA rats. The project paves way for utilizing the intrinsic therapeutic potential of MSC Exosomes as viral-free, non-immunogenic carriers for OA gene therapy by employing cartilage as a drug depot. Cationic exosomes can be used to deliver other OA gene targets, and can be widely used for targeting other negatively charged tissues like meniscus, ligaments, discs, fracture callus etc.

Cardiorespiratory and autonomic impacts of coolants in e-cigarette aerosols

PROJECT SUMMARY / ABSTRACT Coolants such as menthol, WS-3, and WS-23 are widely used in electronic cigarettes (e-cigs) to reduce irritation and enhance appeal—especially among youth. Despite their prevalence, the cardiopulmonary toxicity of these agents remains poorly characterized. Recent work shows that e-cig aerosols can disrupt autonomic nervous system regulation and cardiac electrophysiology, increasing catecholamine release, enhancing sympathetic regulation of cardiac rhythm, and provoking arrhythmias. Proof is also mounting that nicotine’s sympathomimetic traits mediate these pathogenic effects. Preliminary data from our laboratory show that coolants increase systemic nicotine levels, blunt respiratory reflexes, and potentiate arrhythmias upon exposures to e-cigarette aerosols, suggesting a paradoxical role for coolants in suppressing ventilatory responses while intensifying cardiovascular risk. These findings take on added significance in light of recent case reports of sudden cardiac arrest in young e-cigarette users, including some in otherwise healthy individuals. This project will elucidate how e-cigarette coolants alter exposure to harmful and potentially harmful constituents (HPHCs)—particularly nicotine and aldehydes—concurrent with their effects on cardiovascular and respiratory physiology. Using robust murine models with continuous ECG, blood pressure, and pleural pressure telemetry, we will assess how coolants alter the acute and chronic effects of e-cigarette aerosols on cardiac electrophysiology, autonomic tone, ventilatory function, hemodynamics, and toxicant exposure. We will also evaluate how coolant concentration and device power modulate these effects. In parallel, we will determine whether adolescent mice exhibit heightened susceptibility to these effects compared to adults, with attention to sex differences and the persistence of cardiotoxicity after exposure cessation. This comprehensive, multi-modal approach incorporates novel protocols for arrhythmia inducibility, high-resolution physiologic monitoring, and complementary analyses of biomarkers of exposure and effect. By clarifying how coolants interact with HPHCs—especially nicotine and aldehydes—to drive cardiopulmonary injury across age and sex, this work addresses high-priority research areas identified in RFA-OD-25-001, including the toxicological evaluation of e-cigarette constituents and their cardiopulmonary effects. The results will inform regulatory policy and public health strategies aimed at mitigating cardiovascular risk associated with e-cigarette use, particularly among vulnerable youth.

Pilot and Feasibility Program

PILOT AND FEASIBILITY PROGRAM: PROJECT SUMMARY The goal of the Cedars-Sinai Digestive Diseases Research Center (CSDDRC) Pilot and Feasibility (P&F) Program is to provide monetary support, expertise, and technical support to advance innovative basic, translational, and clinical research that matches the overall goal and themes of the Center. The central theme of the CSDDRC is mechanisms and measurements of the fibroinflammatory response in gastrointestinal (GI) tissues, which reflects Center members’ research in three subthemes: 1) Gut Microbiome, 2) Gastrointestinal (GI) and Liver Metabolism, and 3) GI and Liver Injury. The mission of CSDDRC P&F Program is to support new investigators, established investigators who are new to digestive and liver disease research, and established digestive and liver disease investigators who want to start new or collaborative research that promises to lead to a paradigm shift in the digestive diseases field. In partnership with the Enrichment Program, we will provide guidance for P&F awardees in the form of mentorship and collaboration opportunities. The CSDDRC Biomedical Research Cores will also support P&F awardees, facilitating rapid progress of their new and collaborative digestive and liver disease research. The P&F Program’s outcome measures will include the number of high-impact research publications, grant applications, and subsequent extramural funding for P&F awardees. We will accomplish our goals through the following three specific aims. Aim 1 will solicit research proposals from P&F candidates whose proposed research aligns with the central theme and the subthemes of the CSDDRC. We will advertise P&F support widely across campuses, in addition to contacting department/institute directors to solicit their recommendations for promising young and established investigators who are interested in working in digestive and liver diseases. Aim 2 will select pilot project applications that meet CSDDRC P&F Program goals using rigorous review criteria. Each year, the P&F Program will select four pilot projects to be funded by the P30 grant and matched by institutional support. Submitted applications will be peer- reviewed and preliminarily scored based on the NIH review format by three local expert reviewers. Subsequently, after oral presentations by the P&F applicants, the External Advisory Board (EAB) members will undertake a second round of review, scoring, and discussion at the P&F Program Review meeting following the CSDDRC Annual Symposium. Funding decisions will be made during the P&F Program Review meeting. Aim 3 will assist P&F project investigators with career development and obtaining extramural funding for digestive disease research. P&F awardees will benefit from the Enrichment Program’s well-organized mentoring structure, led by experienced members of the CSDDRC, which includes the Grants-in-Progress Mentoring Program, Gastrointestinal Research-in-Progress meetings, and grant application workshops. P&F awardees will also be mentored through direct interactions with P&F Program Directors, Core Directors, members of the Internal Advisory Board and EAB, and individual or collaborative mentor teams.

Circadian regulation of reperfusion efficacy in acute ischemic stroke

Reperfusion with thrombectomy has changed the clinical landscape for ischemic stroke. Recently, some studies suggest that patients with “large cores” may still benefit from reperfusion. Why? If these “cores” represent dead brain, why should reperfusion help? One logical explanation is that currently used neuroimaging “cores”, do not always identify uniformly dead tissue. Our pilot data suggest that these “cores” include tissue with a wide range of injury, indicated as changes in relative CT Hounsfield Units (rHU). Importantly, circadian mechanisms may be involved. Ischemic tissue with less severe changes in rHU tend to occur in the morning (active phase) when responses to reperfusion are better. In mouse models of stroke, ischemic injury is also less severe when strokes occur during the nighttime (active phase for nocturnal animals). In contrast, more severe ischemic injury during the daytime (inactive phase for mice) is accompanied by dampened vasodilation and CBF response along with increased immunothrombosis and neutrophil extracellular traps (NETosis). Is it possible that understanding these circadian mechanisms may help identify patients who respond best to reperfusion? And is it possible that targeting these circadian mechanisms can help convert non- responders into responders? In this multi-PI project, we use a translational approach (clinical neuroimaging and biomarkers in stroke patients, mouse models of stroke, CT-PET imaging of tissue viability, molecular pharmacology) with three integrated aims that can be pursued in parallel. Aim 1 will use neuroimaging in stroke patients to show that less severe rHU values in reperfusion-responsive “cores” tend to occur in the morning, whereas more severe rHU values in reperfusion-non-responsive “cores” occur later. Aim 2 will use clinical biomarkers to show that more severe rHU “cores” that are not reperfusion-responsive correlate with circadian effects on vasodilation and immunothrombosis. Aim 3 will use mouse stroke models to test whether targeting these circadian mechanisms of vasodilation and immunothrombosis can convert reperfusion-non-responders into reperfusion-responders. Patients cannot choose when they have a stroke. So why should we pay attention to circadian mechanisms? There may be 2 reasons that are addressed by the present project. First, thrombectomy is resource-intensive, and in spite of the very low number-needed-to-treat, only 20% of “large core” patients do well after reperfusion. Our studies may help identify who (when) these responders are. Second, the pathophysiologic mechanisms of cerebral ischemia differ depending on time-of-day. Therefore, understanding and then targeting these circadian mechanisms may allow us to convert reperfusion non-responders into responders.

Magnetic resonance true temperature imaging with high spatial and temporal resolution

ABSTRACT The knowledge of temperature and temperature distribution within the brain can be critical to understanding the healthy and diseased brain, its response to acute injury, and in monitoring critically important thermal interventions. There are several temperature sensitive properties such relaxation rates and the proton resonance frequency shift (PRFS) that can be measured with magnetic resonance imaging (MRI) methods but these methods can only measure temperature change. The PRFS method, which provides the most accurate measurement of temperature change can only measure true tissue temperature if the starting true temperature distribution is known. Fortunately, MR spectroscopy (MRS) methods have been developed that show great promise in the measurement of true temperature. These methods rely on the detection of a temperature independent spectral peak of protons bound to carbon atoms in high concentration metabolites, such as N- acetylaspartate (NAA), creatine (Cr) and choline (Cho) which can be used as a reference for the temperature dependent spectral peak of water protons. Both single voxel spectroscopy (SVS) methods and MRS imaging (MRSI) methods have been described but are slow because of the long readout time needed to achieve adequate spectral resolution and the need to perform multiple averages due to the low signal being measured. Echo-planar spectroscopic imaging (EPSI) speeds up MRSI by interleaving an oscillating imaging gradient to spatially encode one of the imaging dimensions simultaneously with spectral readout. Unfortunately, SVS, MRSI, and even EPSI are unsuitable for clinical applications because of the low spatial resolution (voxel size 1 cm3) and temporal resolution (multiple minutes). The goal of this project is to develop an MRI technique that can measure true temperature in the whole brain at spatial and temporal resolutions that enable clinical utility for acutely assessing and longitudinally monitoring healthy and diseased brain tissue, and real time monitoring of thermal interventional therapies. This innovative true temperature measurement technique combines EPSI, for low resolution background field measurements, with PRFS for high spatial and temporal resolution water proton measurements. While conventional EPSI methods interleave volumetric acquisitions with and without water suppression, we propose an innovative modification to take advantage of the very strong water signal to obtain a very high resolution, dynamic method for true temperature measurements. The MRI pulse sequence will be refined, validated (Aim 1), applied to healthy subjects and post-surgery patients at risk for infections (Aim 2), and applied to essential tremor (ET) patients during the required delay between repeated focused ultrasound sonications (Aim 3). Successful completion of the aims of this study will result in a clinically practical method to obtain true temperature measurements in the brain with a spatial and temporal resolution sufficiently high to meet the needs of monitoring focal thermal therapy treatments as well as to provide true temperature measurements over the entire brain for assessment of the state of the brain with disease, infection, and injury.

2-Deoxyglucose Therapy for Organophosphate Intoxication

Project Summary The main goal of this project is to determine the therapeutic potential of glycolysis inhibition as an adjunct to midazolam therapy in mitigating the long-term neurological effects from acute organophosphate pesticide and nerve agent (OPNA) exposure. Novel countermeasures are desperately needed for effective mitigation of morbidity and long-term effects of OPNAs. A variety of agents targeting glutamate, GABA and oxidative stress have been proposed, but glycolysis inhibitors have not been widely studied in OPNA intoxication. Dysregulated glucose metabolism plays a key role in seizures and neuronal injury following OPNA exposure. 2-Deoxyglucose (2-DG), a selective glycolysis inhibitor, has anticonvulsant and neuroprotection effects and hence can effectively mitigate acute and long-term OPNA neurotoxicity. In this project, we seek to identify the glycolysis inhibition as novel adjunct neuroprotection to midazolam therapy for OPNA exposure, with the goal of identifying 2-DG or related drugs as medical countermeasures. The glycolytic pathway represents a logical target for such intervention because glycolysis controls seizures and neuronal injury by regulating glucose utilization and activity in neurons and astrocytes in the brain. The proposed therapy is based on the hypothesis that acute OPNA neurotoxicity imparts sustained activation of the glycolysis pathway in the brain and therefore, 2- DG and selective glycolysis inhibitors prevents long-term neuronal damage neurological dysfunction. This hypothesis will be tested by using the FDA-approved (2-DG) or clinical-stage glycolytic inhibitors in two distinct OPNA models in rats: (Aim 1) To investigate the protective efficacy of 2-DG and novel glycolysis inhibitors against DFP-induced acute and long-term neuronal damage and neurological dysfunction. (Aim 2) Aim 2 (Year 2). To determine brain penetration, pilot toxicity and pharmacokinetic of 2-DG or other lead drug in naïve and DFP-exposed animals. Test drugs will be evaluated as per the NIH rigor criteria in a dose-related design in male and female rats and behavior/neuropathology will be checked for 3 months post-exposure. 2-DG and test drugs will be given starting 40-min after exposure to ONAs. Three primary outcome measures will be addressed for therapy effectiveness: (i) acute adjunct neuroprotection; (ii) chronic neuroprotectant efficacy; and (iii) prevention of neurological and behavioral deficits. The primary measures of neuroprotection include longitudinal MRI scanning, and extent of neurodegeneration, neuroinflammation, aberrant neurogenesis, and mossy fiber sprouting. Key neurological outcomes include memory deficits, depression, anxiety behavior, and neurological/motor deficits. The outcome of this project will provide “proof-of-efficacy” of a novel glycolytic therapy with FDA-approvable, repurposed drugs with promising potential to limit long-term effects of OPNAs in humans. Thus, the overall impact of the outcome is enormous for civilians, especially in developing a highly effective and safe post-exposure medical countermeasure for chemical nerve agents.

Intrinsic and extrinsic mechanisms underlying trigeminal nerve deficits in familial dysautonomia

PROJECT SUMMARY Rare diseases impose a significant burden on the US healthcare system, accounting for nearly half of all expenditures for their treatment. This statistic alone supports the need to invest in research to develop therapeutic interventions for rare diseases since the economic benefit outweighs the continued expense of financial resources. Familial dysautonomia (FD) is a rare, hereditary disease that arises from a splice site mutation in Elongator acetyltransferase complex subunit 1 (ELP1) and impacts the nervous system. To date, FD patients continue to face life-threatening complications involving basic involuntary functions like swallowing and somatosensation because there is no cure for this ultimately fatal neuropathy. FD patients exhibit symptoms due to defects in their somatosensory trigeminal nerves, whose cell bodies reside in the trigeminal ganglion (TG) and are derived from neural crest and placode cells. Recent studies from our lab using an FD mouse model (Elp1 deleted from neural crest cells) revealed TG axon outgrowth and target tissue innervation deficits, recapitulating phenotypes observed in FD patients. However, the mechanisms by which Elp1 mediates normal TG development, and how this goes awry in FD, remain largely elusive. To gain insight into Elp1 function, we performed mass spectrometry to evaluate the TG proteome of normal and FD mouse embryos. Our results uncovered statistically significant increases in extracellular matrix (ECM) and ECM binding proteins, pointing to altered TG biomechanical properties and, more broadly, changes in mechanotransduction, the process by which cells translate extrinsic cues into intrinsic signaling pathways that modulate gene expression. Importantly, proper axon outgrowth relies upon mechanotransduction as growth cones on axons sense and respond to their environment. In the head, this environment consists of ECM and cranial mesenchyme cells, but the impact of Elp1 loss from the latter is not known, including the potential for altered tissue biomechanics that could influence TG axon outgrowth. We hypothesize that loss of Elp1 induces changes in the biomechanical properties of both the TG/nerves and ECM/cranial mesenchyme, modifying mechanotransduction and leading to TG defects in FD, which we will interrogate in the following Specific Aims: 1) define the biomechanical properties of the TG/nerves and ECM/cranial mesenchyme and 2) determine the role of cranial mesenchyme Elp1 in mediating proper TG axon outgrowth. Our innovative research proposal takes a systems-level, multidisciplinary approach involving embryology, biomechanics, and high-resolution microscopy, with the goal of integrating molecular, cellular, and tissue data. These results will significantly advance our knowledge of the molecular mechanisms underscoring TG development and, collectively, inform treatment strategies for birth defects or disorders like FD with TG dysfunction, as well as nerve repair and/or regeneration after injury or disease.

Primary cilia protein IFT88 governs smooth muscle phenotype and vascular remodeling

Project Summary/Abstract Cardiovascular disease remains the leading cause of death in the United States, accounting for nearly 1 million deaths in 2022. Vascular diseases such as atherosclerosis, aneurysm, and coronary artery disease are regulated largely by smooth muscle cells (SMCs) residing in the blood vessel wall. The central dogma of vascular SMC biology is that differentiated cells can de-differentiate and give rise to a spectrum of alternative phenotypes promoting invasion, proliferation, fibrosis, and inflammation, but the mechanisms regulating SMC phenotypic transitions are poorly understood. Intraflagellar transport 88 (IFT88) is an essential protein for the formation of primary cilia, centriole-associated plasma membrane organelles that project into the extracellular milieu and regulate cell cycle reentry and responses to stimuli like growth factors and mechanical strain. Non- ciliary functions of IFT88 also include progression of the cell cycle checkpoint and polarized motility, both of which are functionally critical for SMC-mediated vascular remodeling. Little is known about the functional role of the primary cilia in SMCs and the role of the essential cilia protein IFT88 in regulating SMC phenotype. To address this gap in knowledge, my postdoctoral studies focus on the role of IFT88 in the context of intimal hyperplasia (K99). During the independent phase (R00), I will apply these findings to arteriovenous fistula (AVF) maturation, a surgical intervention often required for dialysis individuals with polycystic kidney disease (PKD), an IFT88 loss-of-function disease. I will test my central hypothesis that cilia are key regulators of SMC phenotype in three Specific Aims: 1) determine the role of IFT88-dependent SMC primary cilia in mechanotransduction of extracellular matrix (ECM) stiffness (K99), 2) determine the role of IFT88 in pathological intimal hyperplasia (K99), and 3) test whether SMC IFT88 expression is required for adaptive remodeling of grafted veins following AVF placement (R00). Overall, we propose that IFT88+ ciliated SMC represent an unidentified subclass of the SMC phenotype spectrum that is primarily responsible for vascular remodeling and is an attractive potential target for treatment of vascular diseases. Building on strong existing collaborations, we have formed a research and mentoring team with expertise in SMC pathophysiology, primary cilia biology, mechanobiology, AVF surgery, and PKD to complete the proposed aims. The additional training in cell-ECM interactions (Aim 1, K99), in vivo murine ligation injury and in vivo cilia imaging (Aim 2, K99), and AVF surgery and PKD pathology (Aim 3, R00) will be indispensable for preparing the PI, Dr. O’Brien, for his career as an independent investigator. Completion of the proposed aims will also contribute directly to an understanding of the function of IFT88-dependent primary cilia in SMCs and may likely identify novel therapeutic targets for treatment of vascular diseases.

MRI investigation of orientation-dependent changes in microstructure and function in a mouse model of mild traumatic brain injury

Harnessing Big Data in Neuroscience: From Mapping Brain Connectivity to Predicting Traumatic Brain Injury

Neuroscience is experiencing unprecedented growth in dataset size both within individual brains and across populations. Large-scale, multimodal datasets are transforming our understanding of brain structure and function, creating opportunities to address previously unexplored questions. However, managing this increasing data volume requires new training and technology approaches. Modern data technologies are reshaping neuroscience by enabling researchers to tackle complex questions within a Ph.D. or postdoctoral timeframe. I will discuss cloud-based platforms such as brainlife.io, that provide scalable, reproducible, and accessible computational infrastructure. Modern data technology can democratize neuroscience, accelerate discovery and foster scientific transparency and collaboration. Concrete examples will illustrate how these technologies can be applied to mapping brain connectivity, studying human learning and development, and developing predictive models for traumatic brain injury (TBI). By integrating cloud computing and scalable data-sharing frameworks, neuroscience can become more impactful, inclusive, and data-driven..

Structural & Functional Neuroplasticity in Children with Hemiplegia

About 30% of children with cerebral palsy have congenital hemiplegia, resulting from periventricular white matter injury, which impairs the use of one hand and disrupts bimanual co-ordination. Congenital hemiplegia has a profound effect on each child's life and, thus, is of great importance to the public health. Changes in brain organization (neuroplasticity) often occur following periventricular white matter injury. These changes vary widely depending on the timing, location, and extent of the injury, as well as the functional system involved. Currently, we have limited knowledge of neuroplasticity in children with congenital hemiplegia. As a result, we provide rehabilitation treatment to these children almost blindly based exclusively on behavioral data. In this talk, I will present recent research evidence of my team on understanding neuroplasticity in children with congenital hemiplegia by using a multimodal neuroimaging approach that combines data from structural and functional neuroimaging methods. I will further present preliminary data regarding functional improvements of upper extremities motor and sensory functions as a result of rehabilitation with a robotic system that involves active participation of the child in a video-game setup. Our research is essential for the development of novel or improved neurological rehabilitation strategies for children with congenital hemiplegia.

Traumatic brain injury and the visual sequela

Metabolic-functional coupling of parvalbmunin-positive GABAergic interneurons in the injured and epileptic brain

Parvalbumin-positive GABAergic interneurons (PV-INs) provide inhibitory control of excitatory neuron activity, coordinate circuit function, and regulate behavior and cognition. PV-INs are uniquely susceptible to loss and dysfunction in traumatic brain injury (TBI) and epilepsy but the cause of this susceptibility is unknown. One hypothesis is that PV-INs use specialized metabolic systems to support their high-frequency action potential firing and that metabolic stress disrupts these systems, leading to their dysfunction and loss. Metabolism-based therapies can restore PV-IN function after injury in preclinical TBI models. Based on these findings, we hypothesize that (1) PV-INs are highly metabolically specialized, (2) these specializations are lost after TBI, and (3) restoring PV-IN metabolic specializations can improve PV-IN function as well as TBI-related outcomes. Using novel single-cell approaches, we can now quantify cell-type-specific metabolism in complex tissues to determine whether PV-IN metabolic dysfunction contributes to the pathophysiology of TBI.

Brain-heart interactions at the edges of consciousness

Various clinical cases have provided evidence linking cardiovascular, neurological, and psychiatric disorders to changes in the brain-heart interaction. Our recent experimental evidence on patients with disorders of consciousness revealed that observing brain-heart interactions helps to detect residual consciousness, even in patients with absence of behavioral signs of consciousness. Those findings support hypotheses suggesting that visceral activity is involved in the neurobiology of consciousness and sum to the existing evidence in healthy participants in which the neural responses to heartbeats reveal perceptual and self-consciousness. Furthermore, the presence of non-linear, complex, and bidirectional communication between brain and heartbeat dynamics can provide further insights into the physiological state of the patient following severe brain injury. These developments on methodologies to analyze brain-heart interactions open new avenues for understanding neural functioning at a large-scale level, uncovering that peripheral bodily activity can influence brain homeostatic processes, cognition, and behavior.

Blood-brain barrier dysfunction in epilepsy: Time for translation

The neurovascular unit (NVU) consists of cerebral blood vessels, neurons, astrocytes, microglia, and pericytes. It plays a vital role in regulating blood flow and ensuring the proper functioning of neural circuits. Among other, this is made possible by the blood-brain barrier (BBB), which acts as both a physical and functional barrier. Previous studies have shown that dysfunction of the BBB is common in most neurological disorders and is associated with neural dysfunction. Our studies have demonstrated that BBB dysfunction results in the transformation of astrocytes through transforming growth factor beta (TGFβ) signaling. This leads to activation of the innate neuroinflammatory system, changes in the extracellular matrix, and pathological plasticity. These changes ultimately result in dysfunction of the cortical circuit, lower seizure threshold, and spontaneous seizures. Blocking TGFβ signaling and its associated pro-inflammatory pathway can prevent this cascade of events, reduces neuroinflammation, repairs BBB dysfunction, and prevents post-injury epilepsy, as shown in experimental rodents. To further understand and assess BBB integrity in human epilepsy, we developed a novel imaging technique that quantitatively measures BBB permeability. Our findings have confirmed that BBB dysfunction is common in patients with drug-resistant epilepsy and can assist in identifying the ictal-onset zone prior to surgery. Current clinical studies are ongoing to explore the potential of targeting BBB dysfunction as a novel treatment approach and investigate its role in drug resistance, the spread of seizures, and comorbidities associated with epilepsy.

Programmed axon death: from animal models into human disease

Programmed axon death is a widespread and completely preventable mechanism in injury and disease. Mouse and Drosophila studies define a molecular pathway involving activation of SARM1 NA Dase and its prevention by NAD synthesising enzyme NMNAT2 . Loss of axonal NMNAT2 causes its substrate, NMN , to accumulate and activate SARM1 , driving loss of NAD and changes in ATP , ROS and calcium. Animal models caused by genetic mutation, toxins, viruses or metabolic defects can be alleviated by blocking programmed axon death, for example models of CMT1B , chemotherapy-induced peripheral neuropathy (CIPN), rabies and diabetic peripheral neuropathy (DPN). The perinatal lethality of NMNAT2 null mice is completely rescued, restoring a normal, healthy lifespan. Animal models lack the genetic and environmental diversity present in human populations and this is problematic for modelling gene-environment combinations, for example in CIPN and DPN , and identifying rare, pathogenic mutations. Instead, by testing human gene variants in WGS datasets for loss- and gain-of-function, we identified enrichment of rare SARM1 gain-of-function variants in sporadic ALS , despite previous negative findings in SOD1 transgenic mice. We have shown in mice that heterozygous SARM1 loss-of-function is protective from a range of axonal stresses and that naturally-occurring SARM1 loss-of-function alleles are present in human populations. This enables new approaches to identify disorders where blocking SARM1 may be therapeutically useful, and the existence of two dominant negative human variants in healthy adults is some of the best evidence available that drugs blocking SARM1 are likely to be safe. Further loss- and gain-of-function variants in SARM1 and NMNAT2 are being identified and used to extend and strengthen the evidence of association with neurological disorders. We aim to identify diseases, and specific patients, in whom SARM1 -blocking drugs are most likely to be effective.

Brain-muscle signaling coordinates exercise adaptations in Drosophila

Chronic exercise is a powerful intervention that lowers the incidence of most age-related diseases while promoting healthy metabolism in humans. However, illness, injury or age prevent many humans from consistently exercising. Thus, identification of molecular targets that can mimic the benefits of exercise would be a valuable tool to improve health outcomes of humans with neurodegenerative or mitochondrial diseases, or those with enforced sedentary lifestyles. Using a novel exercise platform for Drosophila, we have identified octopaminergic neurons as a key subset of neurons that are critical for the exercise response, and shown that periodic daily stimulation of these neurons can induce a systemic exercise response in sedentary flies. Octopamine is released into circulation where it signals through various octopamine receptors in target tissues and induces gene expression changes similar to exercise. In particular, we have identified several key molecules that respond to octopamine in skeletal muscle, including the mTOR modulator Sestrin, the PGC-1α homolog Spargel, and the FNDC5/Irisin homolog Iditarod. We are currently testing these molecules as potential therapies for multiple diseases that reduce mobility, including the PolyQ disease SCA2 and the mitochondrial disease Barth syndrome.

Untitled Seminar

Heiko Luhmann (Germany) – How neuronal activity builds the cerebral cortex; Mary Tolcos (Australia) – Cortical development and fetal brain injury; Silvia Velasco (Australia) – Human brain organoids to study neurodevelopment and disease

Pro-regenerative functions of microglia in demyelinating diseases

Our goal is to understand why myelin repair fails in multiple sclerosis and to develop regenerative medicines for the nervous system. A central obstacle for progress in this area has been the complex biology underlying the response to CNS injury. Acute CNS damage is followed by a multicellular response that encompasses different cell types and spans different scales. Currently, we do not understand which factors determines lesion recovery. Failure of inflammation to resolve is a key underlying reason of poor regeneration, and one focus is therefore on the biology of microglia during de- and remyelination, and their cross talk to other cells, in particular oligodendrocytes and the progenitor cells. In addition, we are exploring the link between lipid metabolism and inflammation, and its role in the regulation of regeneration. I will report about our recent progress in our understanding of how microglia promote regeneration in the CNS.

Reconstructing inhibitory circuits in a damaged brain

Inhibitory interneurons govern the sparse activation of principal cells that permits appropriate behaviors, but they among the most vulnerable to brain damage. Our recent work has demonstrated important roles for inhibitory neurons in disorders of brain development, injury and epilepsy. These studies have motivated our ongoing efforts to understand how these cells operate at the synaptic, circuit and behavioral levels and in designing new technologies targeting specific populations of interneurons for therapy. I will discuss our recent efforts examining the role of interneurons in traumatic brain injury and in designing cell transplantation strategies - based on the generation of new inhibitory interneurons - that enable precise manipulation of inhibitory circuits in the injured brain. I will also discuss our ongoing efforts using monosynaptic virus tracing and whole-brain clearing methods to generate brain-wide maps of inhibitory circuits in the rodent brain. By comprehensively mapping the wiring of individual cell types on a global scale, we have uncovered a fundamental strategy to sustain and optimize inhibition following traumatic brain injury that involves spatial reorganization of local and long-range inputs to inhibitory neurons. These recent findings suggest that brain damage, even when focally restricted, likely has a far broader affect on brain-wide neural function than previously appreciated.

Post-traumatic headache

Concussion (mild traumatic brain injury) affects approximately 50 million people annually. Headache is the most common symptom after concussion and persists in up to 50% of those affected for at least one-year. The biological underpinnings of and the efficacy and tolerability of treatments for post-traumatic headache has historically received little attention. While treatment in clinical practice is mostly directly at the underlying phenotype of the headache, persistent post-traumatic headache is considered to be less responsive to treatments used to treat migraine or tension-type headache. Over the past several years, significant pre-clinical research has begun to elucidate the mechanism(s) involved in the development of post-traumatic headache, and a concerted effort to evaluate the efficacy of selected treatments for persistent post-traumatic headache has begun. This presentation will review the epidemiology, pathophysiology, and emerging data on the prevention and treatment of post-traumatic headache.

Deception, ExoNETs, SmushWare & Organic Data: Tech-facilitated neurorehabilitation & human-machine training

Making use of visual display technology and human-robotic interfaces, many researchers have illustrated various opportunities to distort visual and physical realities. We have had success with interventions such as error augmentation, sensory crossover, and negative viscosity.  Judicial application of these techniques leads to training situations that enhance the learning process and can restore movement ability after neural injury. I will trace out clinical studies that have employed such technologies to improve the health and function, as well as share some leading-edge insights that include deceiving the patient, moving the "smarts" of software into the hardware, and examining clinical effectiveness

Mechanisms of Axon Growth and Regeneration

Almost everybody that has seen neurons under a microscope for the first time is fascinated by their beauty and their complex shape. Early on during development, however, there are hardly any signs of their future complexity, but the neurons look round and simple. How do neurons develop their sophisticated structure? How do they initially generate domains that later have distinct function within neuronal circuits, such as the axon? And, can a better understanding of the underlying developmental mechanisms help us in pathological conditions, such as a spinal cord injury, to induce axons to regenerate? Here, I will talk about the cytoskeleton as a driving force for neuronal polarization. We will then explore how cytoskeletal changes help to reactivate the growth program of injured CNS axons to elicit axon regeneration after a spinal cord injury. Finally, we will discuss whether axon growth and synapse formation may be processes in neurons that might exclude each other. Following this developmental hypothesis, it will help us to generate a novel perspective on regeneration failure in the adult CNS, and how we can overcome this failure to induce axon regeneration. Thus, this talk will describe how we can exploit developmental mechanisms to induce axon regeneration after a spinal cord injury.

Mechanisms of sleep-seizure interactions in tuberous sclerosis and other mTORpathies

An intriguing, relatively unexplored therapeutic avenue to investigate epilepsy is the interaction of sleep mechanisms and seizures. Multiple lines of clinical observations suggest a strong, bi-directional relationship between epilepsy and sleep. Epilepsy and sleep disorders are common comorbidities. Seizures occur more commonly in sleep in many types of epilepsy, and in turn, seizures can cause disrupted sleep. Sudden unexplained death in epilepsy (SUDEP) is strongly associated with sleep. The biological mechanisms underlying this relationship between seizures and sleep are poorly understood, but if better delineated, could offer novel therapeutic approaches to treating both epilepsy and sleep disorders. In this presentation, I will explore this sleep-seizure relationship in mouse models of epilepsy. First, I will present general approaches for performing detailed longitudinal sleep and vigilance state analysis in mice, including pre-weanling neonatal mice. I will then discuss recent data from my laboratory demonstrating an abnormal sleep phenotype in a mouse model of the genetic epilepsy, tuberous sclerosis complex (TSC), and its relationship to seizures. The potential mechanistic basis of sleep abnormalities and sleep-seizure interactions in this TSC model will be investigated, focusing on the role of the mechanistic target of rapamycin (mTOR) pathway and hypothalamic orexin, with potential therapeutic applications of mTOR inhibitors and orexin antagonists. Finally, similar sleep-seizure interactions and mechanisms will be extended to models of acquired epilepsy due to status epilepticus-related brain injury.

JAK/STAT regulation of the transcriptomic response during epileptogenesis

Temporal lobe epilepsy (TLE) is a progressive disorder mediated by pathological changes in molecular cascades and neural circuit remodeling in the hippocampus resulting in increased susceptibility to spontaneous seizures and cognitive dysfunction. Targeting these cascades could prevent or reverse symptom progression and has the potential to provide viable disease-modifying treatments that could reduce the portion of TLE patients (>30%) not responsive to current medical therapies. Changes in GABA(A) receptor subunit expression have been implicated in the pathogenesis of TLE, and the Janus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) pathway has been shown to be a key regulator of these changes. The JAK/STAT pathway is known to be involved in inflammation and immunity, and to be critical for neuronal functions such as synaptic plasticity and synaptogenesis. Our laboratories have shown that a STAT3 inhibitor, WP1066, could greatly reduce the number of spontaneous recurrent seizures (SRS) in an animal model of pilocarpine-induced status epilepticus (SE). This suggests promise for JAK/STAT inhibitors as disease-modifying therapies, however, the potential adverse effects of systemic or global CNS pathway inhibition limits their use. Development of more targeted therapeutics will require a detailed understanding of JAK/STAT-induced epileptogenic responses in different cell types. To this end, we have developed a new transgenic line where dimer-dependent STAT3 signaling is functionally knocked out (fKO) by tamoxifen-induced Cre expression specifically in forebrain excitatory neurons (eNs) via the Calcium/Calmodulin Dependent Protein Kinase II alpha (CamK2a) promoter. Most recently, we have demonstrated that STAT3 KO in excitatory neurons (eNSTAT3fKO) markedly reduces the progression of epilepsy (SRS frequency) in the intrahippocampal kainate (IHKA) TLE model and protects mice from kainic acid (KA)-induced memory deficits as assessed by Contextual Fear Conditioning. Using data from bulk hippocampal tissue RNA-sequencing, we further discovered a transcriptomic signature for the IHKA model that contains a substantial number of genes, particularly in synaptic plasticity and inflammatory gene networks, that are down-regulated after KA-induced SE in wild-type but not eNSTAT3fKO mice. Finally, we will review data from other models of brain injury that lead to epilepsy, such as TBI, that implicate activation of the JAK/STAT pathway that may contribute to epilepsy development.

NMC4 Short Talk: Decoding finger movements from human posterior parietal cortex

Restoring hand function is a top priority for individuals with tetraplegia. This challenge motivates considerable research on brain-computer interfaces (BCIs), which bypass damaged neural pathways to control paralyzed or prosthetic limbs. Here, we demonstrate the BCI control of a prosthetic hand using intracortical recordings from the posterior parietal cortex (PPC). As part of an ongoing clinical trial, two participants with cervical spinal cord injury were each implanted with a 96-channel array in the left PPC. Across four sessions each, we recorded neural activity while they attempted to press individual fingers of the contralateral (right) hand. Single neurons modulated selectively for different finger movements. Offline, we accurately classified finger movements from neural firing rates using linear discriminant analysis (LDA) with cross-validation (accuracy = 90%; chance = 17%). Finally, the participants used the neural classifier online to control all five fingers of a BCI hand. Online control accuracy (86%; chance = 17%) exceeded previous state-of-the-art finger BCIs. Furthermore, offline, we could classify both flexion and extension of the right fingers, as well as flexion of all ten fingers. Our results indicate that neural recordings from PPC can be used to control prosthetic fingers, which may help contribute to a hand restoration strategy for people with tetraplegia.

What transcriptomics tells us about retinal development, disease and evolution

Classification of neurons, long viewed as a fairly boring enterprise, has emerged as a major bottleneck in analysis of neural circuits. High throughput single cell RNA-seq has provided a new way to improve the situation. We initially applied this method to mouse retina, showing that its five neuronal classes (photoreceptors, three groups of interneurons, and retinal ganglion cells) can be divided into 130 discrete types. We then applied the method to other species including human, macaque, zebrafish and chick. With the atlases in hand, we are now using them to address questions about how retinal cell types diversify, how they differ in their responses to injury and disease, and the extent to which cell classes and types are conserved among vertebrates.

Keeping axons alive after injury: Inhibiting programmed axon death

Activation of pro-degenerative protein SARM1 in response to diverse physical and disease-relevant injuries triggers programmed axon death. Original studies indicated substantially decreased levels of SARM1 were required for neuroprotection. However, we demonstrate that lowering SARM1 levels by 50% in Sarm1 haploinsufficient mice delays axon degeneration in vivo (after sciatic nerve transection), in vitro (in response to diverse traumatic, neurotoxic, and genetic triggers), and partially prevents neurite outgrowth defects in mice lacking pro-survival factor NMNAT2. We also demonstrate the capacity for Sarm1 antisense oligonucleotides to decrease SARM1 levels by more than 50% which delays or prevents programmed axon degeneration in vitro. Combining Sarm1 haploinsufficiency with antisense oligonucleotides further decreases SARM1 levels and prolongs protection after neurotoxic injuries. These data demonstrate that axon protection occurs in a Sarm1 gene-dose responsive manner and that SARM1 lowering agents have therapeutic potential. Thus, antisense oligonucleotide targeting of Sarm1 is a promising therapeutic strategy against diverse triggers of axon degeneration.

Neural Population Dynamics for Skilled Motor Control

The ability to reach, grasp, and manipulate objects is a remarkable expression of motor skill, and the loss of this ability in injury, stroke, or disease can be devastating. These behaviors are controlled by the coordinated activity of tens of millions of neurons distributed across many CNS regions, including the primary motor cortex. While many studies have characterized the activity of single cortical neurons during reaching, the principles governing the dynamics of large, distributed neural populations remain largely unknown. Recent work in primates has suggested that during the execution of reaching, motor cortex may autonomously generate the neural pattern controlling the movement, much like the spinal central pattern generator for locomotion. In this seminar, I will describe recent work that tests this hypothesis using large-scale neural recording, high-resolution behavioral measurements, dynamical systems approaches to data analysis, and optogenetic perturbations in mice. We find, by contrast, that motor cortex requires strong, continuous, and time-varying thalamic input to generate the neural pattern driving reaching. In a second line of work, we demonstrate that the cortico-cerebellar loop is not critical for driving the arm towards the target, but instead fine-tunes movement parameters to enable precise and accurate behavior. Finally, I will describe my future plans to apply these experimental and analytical approaches to the adaptive control of locomotion in complex environments.

Improving Communication With the Brain Through Electrode Technologies

Over the past 30 years bionic devices such as cochlear implants and pacemakers, have used a small number of metal electrodes to restore function and monitor activity in patients following disease or injury of excitable tissues. Growing interest in neurotechnologies, facilitated by ventures such as BrainGate, Neuralink and the European Human Brain Project, has increased public awareness of electrotherapeutics and led to both new applications for bioelectronics and a growing demand for less invasive devices with improved performance. Coupled with the rapid miniaturisation of electronic chips, bionic devices are now being developed to diagnose and treat a wide variety of neural and muscular disorders. Of particular interest is the area of high resolution devices that require smaller, more densely packed electrodes. Due to poor integration and communication with body tissue, conventional metallic electrodes cannot meet these size and spatial requirements. We have developed a range of polymer based electronic materials including conductive hydrogels (CHs), conductive elastomers (CEs) and living electrodes (LEs). These technologies provide synergy between low impedance charge transfer, reduced stiffness and an ability to be provide a biologically active interface. A range of electrode approaches are presented spanning wearables, implantables and drug delivery devices. This talk outlines the materials development and characterisation of both in vitro properties and translational in vivo performance. The challenges for translation and commercial uptake of novel technologies will also be discussed.

Converging mechanisms of epileptogenesis after brain injury

Traumatic brain injury (TBI), a leading cause of acquired epilepsy, results in primary cellular injury as well as secondary neurophysiological and inflammatory responses which contribute to epileptogenesis. I will present our recent studies identifying a role for neuro-immune interactions, specifically, the innate immune receptor Toll-like receptor 4 (TLR4), in enhancing network excitability and cell loss in hippocampal dentate gyrus early after concussive brain injury. I will describe results indicating that the transient post-traumatic increases in dentate neurogenesis which occurs during the same early post-injury period augments dentate network excitability and epileptogenesis. I will provide evidence for the beneficial effects of targeting TLR4 and neurogenesis early after brain injury in limiting epileptogenesis. We will discuss potential mechanisms for convergence of the post-traumatic neuro-immune and neurogenic changes and the implications for therapies to reduce neurological deficits and epilepsy after brain injury.

From Vulnerable Plaque to Vulnerable Brain: Understanding the Role of Inflammation in Vascular Health, Stroke, and Cerebrovascular Disease

Every year around 100,000 people in the UK will have a stroke. Stroke is a leading cause of adult disability, and cerebrovascular disease more broadly is a major cause of dementia. Understanding these diseases – both acute and chronic manifestations of cerebrovascular disease – requires consideration not only of the brain itself, but also the blood vessels supplying it. Atherosclerosis – the hardening of arteries as we age – may predispose to stroke by triggering the formation of blood clots that block the blood supply to the brain, but also involves inflammation that may cause chronic damage to the brain and prime both the brain and body for injury. Understanding this interaction between systemic disease and brain health may have important implications for our understanding of healthy ageing and provide novel therapeutic approaches for reducing the burden of cerebrovascular disease. This talk will consider how advances in imaging may facilitate our understanding of the processes underlying atherosclerosis and how it affects the brain in stroke, as well as work currently underway to translate this understanding into improving treatments for stroke.

Overdrawn at the ion bank: brain injury, neuronal chloride levels, and seizures

The role of the complement pathway in post-traumatic sleep disruption and epilepsy

While traumatic brain injury (TBI) acutely disrupts the cortex, most TBI-related disabilities reflect secondary injuries that accrue over time. The thalamus is a likely site of secondary damage because of its reciprocal connections with the cortex. Using a mouse model of mild cortical injury that does not directly damage subcortical structures (mTBI), we found a chronic increase in C1q expression specifically in the corticothalamic circuit. Increased C1q expression co-localized with neuron loss and chronic inflammation, and correlated with disruption in sleep spindles and emergence of epileptic activities. Blocking C1q counteracted these outcomes, suggesting that C1q is a disease modifier in mTBI. Single-nucleus RNA sequencing demonstrated that microglia are the source of thalamic C1q. Since the corticothalamic circuit is important for cognition and sleep, which can be impaired by TBI, this circuit could be a new target for treating TBI-related disabilities

Making spinal sensory interneurons from stem cells for regenerative therapies

Dr. Gupta is carrying out his post doctoral studies in the Buter Laboratory in UCLA. He is applying his his knowledge of embryology to stem cells for developing regenerative therapies to treat spinal cord injuries. In this talk, he will discuss how understanding the logic for spinal cord development led us to derive diverse sensory neuronal classes from embryonic stem cells. The spinal sensory neurons enableus to perceive our environment through modalities that are lost in spinal injury patients. These ESC derived senory neurons can help regain sensation in spina cord injury patients through regenerative therapies.

Sympathetic control of lymph node function

Peripheral nerve injury can cause debilitating disease and immune-cell mediated destruction of the affected nerve. While the focus of most studies has been on the nerve-degenerative response, the effect of loss of innervation on lymph node function is largely unclear. Here, I will discuss the cellular and molecular events caused by local denervation and loss of direct neural input to the popliteal lymph node that induce an inflammatory response and lymph node expansion.

Hughlings Jackson Lecture: Making Progress in Progressive MS – the Ultimate Challenge!

On April 22, 2021, Dr. Alan J Thompson of the University College London and the UCL Institute of Neurology, London, UK will deliver the Hughlings Jackson Lecture entitled, “Making Progress in Progressive MS – the Ultimate Challenge!” Established in 1935, the Hughlings Jackson Lecture is The Neuro’s premier scientific lecture. It honors the legacy of British neurologist John Hughlings Jackson (1835-1911) who pioneered the development of neurology as a medical specialty. Talk Abstract : The international focus on progressive MS, driven by the Progressive MS Alliance amongst others, together with recent encouraging results from clinical trials have raised the profile and emphasised the importance of understanding, treating and ultimately preventing progression in MS. Effective treatment for Progressive MS is now regarded as the single most important issue facing the MS community. There are several important challenges to developing new treatments for progressive MS. Fundamental to any development in treatment is a better understanding of the mechanisms of tissue injury underpinning progression which will in turn allow the identification of new targets against which treatments can be directed. There are additional complications in determining when progression actually starts, determining the impact of aging and defining the progressive clinical phenotypes – an area which has become increasingly complex in recent months. Evaluating potential new treatments in progressive MS also poses particular challenges including trial design and the selection of appropriate clinical and imaging outcomes - in particular, identifying an imaging biomarker for phase II trials of progressive MS. Despite these challenges, considerable progress is being made in developing new treatments targeting the innate immune system and exploring neuroprotective strategies. Further advances are being driven by a number of international networks, funded by the Progressive MS Alliance. Overall we are seeing encouraging progress as a result of co-ordinated global collaboration which offers real possibilities for truly effective treatment of progression.

Brain Awareness Week @ IITGN

Traumatic injury in the nervous system leads to devastating consequences such as paralysis. The regenerative capacity of the nervous system is limited in adulthood. In this talk, Dr. Anindya would be sharing how the simple nematode C. elegans with its known connectome can inform us about the biology of nervous system repair.

Life of Pain and Pleasure

The ability to experience pain is old in evolutionary terms. It is an experience shared across species. Acute pain is the body’s alarm system, and as such it is a good thing. Pain that persists beyond normal tissue healing time (3-4 months) is defined as chronic – it is the system gone wrong and it is not a good thing. Chronic pain has recently been classified as both a symptom and disease in its own right. It is one of the largest medical health problems worldwide with one in five adults diagnosed with the condition. The brain is key to the experience of pain and pain relief. This is the place where pain emerges as a perception. So, relating specific brain measures using advanced neuroimaging to the change patients describe in their pain perception induced by peripheral or central sensitization (i.e. amplification), psychological or pharmacological mechanisms has tremendous value. Identifying where amplification or attenuation processes occur along the journey from injury to the brain (i.e. peripheral nerves, spinal cord, brainstem and brain) for an individual and relating these neural mechanisms to specific pain experiences, measures of pain relief, persistence of pain states, degree of injury and the subject's underlying genetics, has neuroscientific and potential diagnostic relevance. This is what neuroimaging has afforded – a better understanding and explanation of why someone’s pain is the way it is. We can go ‘behind the scenes’ of the subjective report to find out what key changes and mechanisms make up an individual’s particular pain experience. A key area of development has been pharmacological imaging where objective evidence of drugs reaching the target and working can be obtained. We even now understand the mechanisms of placebo analgesia – a powerful phenomenon known about for millennia. More recently, researchers have been investigating through brain imaging whether there is a pre-disposing vulnerability in brain networks towards developing chronic pain. So, advanced neuroimaging studies can powerfully aid explanation of a subject’s multidimensional pain experience, pain relief (analgesia) and even what makes them vulnerable to developing chronic pain. The application of this goes beyond the clinic and has relevance in courts of law, and other areas of society, such as in veterinary care. Relatively far less work has been directed at understanding what changes in the brain occur during altered states of consciousness induced either endogenously (e.g. sleep) or exogenously (e.g. anaesthesia). However, that situation is changing rapidly. Our recent multimodal neuroimaging work explores how anaesthetic agents produce altered states of consciousness such that perceptual experiences of pain and awareness are degraded. This is bringing us fascinating insights into the complex phenomenon of anaesthesia, consciousness and even the concept of self-hood. These topics will be discussed in my talk alongside my ‘side-story’ of life as a scientist combining academic leadership roles with doing science and raising a family.

Novel mechanisms of neurogenesis and neural repair

In order to re-install neurogenesis after loss of neurons upon injury or neurodegeneration, we need to understand the basic principles of neurogenesis. I will first discuss about our discovery of a novel centrosome protein (Camargo et al., 2019) and discuss unpublished work about the great diversity of interphase centrosome proteomes and their relevance for neurodevelopmental disorders. I would then present work on a master regulator of neural stem cell amplification and brain folding (Stahl et al., 2013; Esgleas et al., 2020) to proceed presenting data on utilizing some of these factors for turning astrocytes into neurons. I will present data on the critical role of mitochondria in this conversion process (Gascon et al., 2016, Russo et al., 2020) and how it regulates the speed of conversion also showing unpublished data. If time permits I may touch on recent progress in in vivo reprogramming (Mattugini et al., 2019). Taken together, these data highlight the surprising specificity and importance of organelle diversity from centrosome, nucleolus and mitochondria as key regulators in development and reprogramming.

Role of Oxytocin in regulating microglia functions to prevent brain damage of the developing brain

Every year, 30 million infants worldwide are delivered after intra-uterine growth restriction (IUGR) and 15 million are born preterm. These two conditions are the leading causes of ante/perinatal stress and brain injury responsible for neurocognitive and behavioral disorders in more than 9 million children each year. Both prematurity and IUGR are associated with perinatal systemic inflammation, a key factor associated with neuroinflammation and identified to be the best predictor of subsequent neurological impairments. Most of pharmacological candidates have failed to demonstrate any beneficial effect to prevent perinatal brain damage. In contrast, environmental enrichment based on developmental care, skin-to-skin contact and vocal/music intervention appears to confer positive effects on brain structure and function. However, mechanisms underlying these effects remain unknown. There is strong evidence that an adverse environment during pregnancy and the perinatal period can influence hormonal responses of the newborn with long-lasting neurobehavioral consequences in infancy and adulthood. Excessive cortisol release in response to perinatal stress induces pro-inflammatory and brain-programming effects. These deleterious effects are known to be balanced by Oxytocin (OT), a neuropeptide playing a key role during the perinatal period and parturition, in social behavior and regulating the central inflammatory response to injury in the adult brain. Using a rodent model of IUGR associated with perinatal brain damage, we recently reported that Carbetocin, a brain permeable long-lasting OT receptor (OTR) agonist, was associated with a significant reduction of activated microglia, the primary immune cells of the brain. Moreover this reduced microglia reactivity was associated to a long-term neuroprotection. These findings make OT a promising candidate for neonatal neuroprotection through neuroinflammation regulation. However, the causality between the endogenous OT and central inflammation response to injury has not been established and will be further studied by the lab.

Plasticity of Pain and Pleasure

What happens when the nervous system fails to adapt? Our perception of the world relies on a nervous system that learns and adapts to sensory information. Based on our experience we can predict what a wooden surface will feel like, that fire is hot, and that a gentle caress from a partner can be soothing. But our sensory experience of the world is not static – warm water can feel like fire on sunburned skin and the gentle brush of our clothes can be excruciating after an injury. In pathological conditions such as chronic pain, changes in nervous system function can cause normally innocuous sensory stimuli to be perceived as aversive or painful long after the initial injury has happened. These changes can sometimes be similar to the formation of a pain ‘memory’ that can modulate and distort our perception of sensory information. Our research program seeks to understand how fundamental processes that govern the formation and maintenance of plastic changes in the nervous system can lead to pathological conditions and how we can reverse engineer these changes to treat chronic conditions.

Microenvironment role in axonal regeneration- looking beyond the neurons

After an injury in the adult mammalian central nervous system, lesioned axons fail to regenerate. This failure to regenerate contrasts with the remarkable potential of axons to grow during embryonic development and after an injury in the peripheral nervous system. Peripheral sensory neurons with cell soma in dorsal root ganglia (DRG) switch to a regenerative state after nerve injury to enable axon regeneration and functional recovery. Decades of research have focused on the signaling pathways elicited by injury in sensory neurons and in Schwann cells that insulate axons as central mechanisms regulating nerve repair. However, neuronal microenvironment is far more complex and is composed of multiple cell types including endothelial, immune and glial cells. Whether the microenvironment surrounding neuronal soma contribute to the poor regenerative outcomes following central injuries remains largely unexplored. To answer this question, we performed a single cell transcriptional profiling of the DRG neuronal microenvironment response to peripheral and central injuries. In dissecting the roles of the microenvironment contribution, we have focused on a poorly studied population of Satellite Glial Cells (SGC) surrounding the neuronal cell soma. This study has uncovered a previously unknown role for SGC in nerve regeneration and defined SGC as transcriptionally distinct from Schwann cells while sharing similarities with astrocytes. Upon a peripheral injury, SGC contribute to axon regeneration via Fatty acid synthase (Fasn)-PPARα signaling pathway. Through repurposing fenofibrate, an FDA- approved PPARα agonist used for dyslipidemia treatment, we were able to rescue the impaired regeneration in mice lacking Fasn in SGC. Our analysis reveals that in response to central injuries, SGC do not activate the PPAR signaling pathway. However, induction of this pathway with fenofibrate treatment, rescued axon regeneration following an injury to the central nerves. Collectively, our results uncovered a previously unappreciated role of the neuronal microenvironment differential response in central and peripheral injuries.

The developing visual brain – answers and questions

We will start our talk with a short video of our research, illustrating methods (some old and new) and findings that have provided our current understanding of how visual capabilities develop in infancy and early childhood. However, our research poses some outstanding questions. We will briefly discuss three issues, which are linked by a common focus on the development of visual attentional processing: (1) How do recurrent cortical loops contribute to development? Cortical selectivity (e.g., to orientation, motion, and binocular disparity) develops in the early months of life. However, these systems are not purely feedforward but depend on parallel pathways, with recurrent feedback loops playing a critical role. The development of diverse networks, particularly for motion processing, may explain changes in dynamic responses and resolve developmental data obtained with different methodologies. One possible role for these loops is in top-down attentional control of visual processing. (2) Why do hyperopic infants become strabismic (cross-eyes)? Binocular interaction is a particularly sensitive area of development. Standard clinical accounts suppose that long-sighted (hyperopic) refractive errors require accommodative effort, putting stress on the accommodation-convergence link that leads to its breakdown and strabismus. Our large-scale population screening studies of 9-month infants question this: hyperopic infants are at higher risk of strabismus and impaired vision (amblyopia and impaired attention) but these hyperopic infants often under- rather than over-accommodate. This poor accommodation may reflect poor early attention processing, possibly a ‘soft sign’ of subtle cerebral dysfunction. (3) What do many neurodevelopmental disorders have in common? Despite similar cognitive demands, global motion perception is much more impaired than global static form across diverse neurodevelopmental disorders including Down and Williams Syndromes, Fragile-X, Autism, children with premature birth and infants with perinatal brain injury. These deficits in motion processing are associated with deficits in other dorsal stream functions such as visuo-motor co-ordination and attentional control, a cluster we have called ‘dorsal stream vulnerability’. However, our neuroimaging measures related to motion coherence in typically developing children suggest that the critical areas for individual differences in global motion sensitivity are not early motion-processing areas such as V5/MT, but downstream parietal and frontal areas for decision processes on motion signals. Although these brain networks may also underlie attentional and visuo-motor deficits , we still do not know when and how these deficits differ across different disorders and between individual children. Answering these questions provide necessary steps, not only increasing our scientific understanding of human visual brain development, but also in designing appropriate interventions to help each child achieve their full potential.

Programmed Axon Death and its Roles in Human Disease

Axons degenerate before the neuronal soma in many neurodegenerative diseases. Programmed axon death (Wallerian degeneration) is a widely-occurring mechanism of axon loss that is well understood and preventable in animals. Its aberrant activation by mutation of the pro-survival gene Nmnat2 directly causes axonopathy in mice with severity ranging from mild polyneuropathy to perinatal lethality. Rare biallelic mutations in the homologous human gene cause related phenotypes in patients. NMNAT2 is a negative regulator of the prodegenerative NADase SARM1. Constitutive activation of SARM1 is cytotoxic and the human SARM1 locus is significantly associated with sporadic ALS. Another negative regulator, STMN2, has also been implicated in ALS, where it is commonly depleted downstream of TDP-43. In mice, programmed axon death can be robustly blocked by deletion of Sarm1, or by overexpression, axonal targeting and/or stabilization of various NMNAT isoforms. This alleviates models of many human disorders including some forms of peripheral neuropathy, motor neuron diseases, glaucoma, Parkinson’s disease and traumatic brain injury, and it confers lifelong rescue on the lethal Nmnat2 null phenotype and other conditions. Drug discovery programs now aim to achieve similar outcomes in human disease. In order to optimize the use of such drugs, we have characterized a range of human NMNAT2 and SARM1 functional variants that underlie a spectrum of axon vulnerability in the human population. Individuals at the vulnerable end of this spectrum are those most likely to benefit from drugs blocking programmed axon death, and disorders associated with these genotypes are promising indications in which to apply them.

Abstraction and Analogy in Natural and Artificial Intelligence

Learning by analogy is a powerful tool children’s developmental repertoire, as well as in educational contexts such as mathematics, where the key knowledge base involves building flexible schemas. However, noticing and learning from analogies develops over time and is cognitively resource intensive. I review studies that provide insight into the relationship between mechanisms driving children’s developing analogy skills, highlighting environmental inputs (parent talk and prior experiences priming attention to relations) and neuro-cognitive factors (Executive Functions and brain injury). I then note implications for mathematics learning, reviewing experimental findings that show analogy can improve learning, but also that both individual differences in EFs and environmental factors that reduce available EFs such as performance pressure can predict student learning.

Microglia function and dysfunction in Alzheimer’s disease

Emerging genetic studies of late-onset Alzheimer’s Disease implicate the brain’s resident macrophages in the pathogenesis of AD. More than half the risk genes associated with late-onset AD are selectively expressed in microglia and peripheral myeloid cells; yet we know little about the underlying biology or how myeloid cells contribute to AD pathogenesis. Using single-cell RNA sequencing and spatial transcriptomics we identified molecular signatures that can be used to localize and monitor distinct microglia functional states in the human and mouse brain. Our results show that microglia assume diverse functional states in development, aging and injury, including populations corresponding to known microglial functions including proliferation, migration, inflammation, and synaptic phagocytosis. We identified several innate immune pathways by which microglia recognize and prune synapses during development and in models of Alzheimer’s disease, including the classical complement cascade. Illuminating the mechanisms by which developing synaptic circuits are sculpted is providing important insight on understanding how to protect synapses in Alzheimer’s and other neurodegenerative diseases of synaptic dysfunction.

Affordable Robots/Computer Systems to Identify, Assess, and Treat Impairment After Brain Injury

Non-traumatic brain injury due to stroke, cerebral palsy and HIV often result in serious long-term disability worldwide, affecting more than 150 million persons globally; with the majority of persons living in low and middle income countries. These diseases often result in varying levels of motor and cognitive impairment due to brain injury which then affects the person’s ability to complete activities of daily living and fully participate in society. Increasingly advanced technologies are being used to support identification, diagnosis, assessment, and therapy for patients with brain injury. Specifically, robot and mechatronic systems can provide patients, physicians and rehabilitation clinical providers with additional support to care for and improve the quality of life of children and adults with motor and cognitive impairment. This talk will provide a brief introduction to the area of rehabilitation robotics and, via case studies, illustrate how computer/technology-assisted rehabilitation systems can be developed and used to assess motor and cognitive impairment, detect early evidence of functional impairment, and augment therapy in high and low-resource settings.

Aberrant cortical spine dynamics after concussive injury are reversed by integrated stress response inhibition

The acute effects of pegylated single-walled carbon nanotubes on the protein oxidative damage and HSP-70 levels in primary mouse astrocytes exposed to stretch injury

Acute intralesional application of extracellular vesicles improves outcomes in a rat model of traumatic spinal cord injury

Alterations of cortical connectivity in a mouse model of premature brain injury

Alterations of locomotion in a model of incomplete cervical spinal cord injury (SCI) in pigs

Altered expression of peripheral microRNAs and pathway signaling after mild traumatic brain injury

Application of the ceftriaxone changes the GLT-1 distribution after traumatic brain injury

Cell-type-specific dendritic changes in the mouse retina during development and in response to injury

Cellular Senescence and Neuroinflammation Following Controlled Cortical Impact Traumatic Brain Injury in Juvenile Mice

Challenging the role of oligodendrocytes upon traumatic brain injury

Chronic intracerebroventricular administration of orexin-A does not modify behavioural outcomes following repetitive mild traumatic brain injury in rats

Comparative model of minimal spinal cord injury reveals superior regenerative potential of nervous tissue during development compared to adulthood

Cortical reorganization after spinal cord injury is layer-specific and time-dependent

Craniectomy Camouflages the Mild Fluid Percussion Injury-induced Changes in Neurogenesis, Neuroinflammation, and Behavior

Deactivating Mast cells and delocalizing Aquaporin-4 avoid early formation of different edema subtypes and prevents sensorimotor impairments after spinal cord injury

BMX deficiency alleviates cognitive and motor impairment after traumatic brain injury

Description of post-traumatic brain lesion in a pediatric murine model of injury

Drebrin controls scar formation and astrocyte reactivity upon traumatic brain injury by regulating membrane trafficking

Dynamic ECM constructs for spinal cord injury repair

Early intravenous infusion of neuroectodermal stem cell exerts beneficial effect on neuroprotection following traumatic spinal cord injury

Effects of the chronic treatment with an A2A/A2B receptor mixed agonist, MRS3997, on cerebral injury in a rat model of transient brain ischemia

Effects of Dorsal Root Avulsion Injury on the Spinal Ganglia and Spinal Cord

Effects of Nuclear receptor Rev-Erbα/β on ischemic brain injury in mice

Effects of pioglitazone on the cortical damage and motor performance following traumatic brain injury in the rat

Effects of stroboscopic visual training on TUG and 6MWT performances in subjects with incomplete spinal cord injury evaluated using DeepLabCut markerless pose estimation system

Emulating the Secondary Injuries of Traumatic Brain Injury and the Exploration of Neurotherapeutics

Evaluation of repetitive mild traumatic brain injury by fluorescence and FDG PET imaging

Excitability of Injured and Non-Injured Neurons after Spared Nerve Injury

Fate mapping of peripherally derived macrophages after traumatic brain injury

Flexible neurotransmitter phenotype of spinal excitatory interneurons regulates locomotor ability after spinal cord injury

The genetic downregulation of calpain 1 reverts spinal hyperexcitability in a neonate mouse model of complete spinal cord injury

A Gut-Brain Connection: Gut Microbiome Composition is Differentially Altered After Repetitive Mild Traumatic Brain Injury in Adolescent and Adult Rats

Human Platelet Proteome improves traumatic brain injury in animal models

The impact of a pre-existing Toxoplasma gondii infection following traumatic brain injury in mice

Inflammation pattern after rat spinal cord injury with a comparative analysis of contusion vs transection experimental models

Inhibition of the NLRP3 inflammasome by OLT1177 induces functional protection and myelin preservation after spinal cord injury

Injury-induced upregulation of fibronectin and BMP4 modulates the differentiation of oligodendrocyte progenitor cells into Schwann cells

Interaction between NO and its derivatives with OGDHC in cerebral cortex upon brain injury

Investigation of sensory neuron-derived CSF1 as a potential chemoattractant factor for macrophages after peripheral nerve injury

AAV-mediated gene therapy for sensory regeneration after spinal cord injury