Washington University

NIH Research Projects · FY 2024 · 2024-09

ABSTRACT: Bacterial infections are a major threat to human health. Many bacteria, particularly Gram-positives, form difficult- to-eradicate biofilms on catheters, cardiac devices and bone implants such as joint replacements. Because of the difficulty in treating established biofilm infections, early detection is advantageous. However, current diagnostic imaging modalities rely on nonspecific host features such as inflammation and edema, rather than detecting the bacteria themselves. The antibiotic vancomycin binds with high affinity and specificity to Gram- positive bacteria, and antibiotic-derivatives have been explored as imaging agents. In this application, we conjugate vancomycin to the siderophore DFOB, which binds with nM affinity to the virulence-essential surface displayed lipoprotein receptor (FhuD2) on S. aureus and other Gram-positives, and is subsequently internalized. DFOB is also an FDA approved chelation agent that forms stable complexes with transition metal PET isotopes (68Ga, 89Zr, and 44Sc). In the first Specific Aim, we test the in vitro affinity and specificity of bivalent radiometal- labeled Vanco-PEG-DFOB on target proteins, on live planktonic bacteria, as well as in clinically relevant biofilm embedded systems. We will determine the role of PEG spacer and transition metal isotope on the binding capability, and compare with monovalent tracers. In the second aim, we test the contrast and detection capacity of Vanco-PEG-DFOB using in vivo models of implant infection for both in-dwelling catheters and periprosthetic joint surfaces. We compare this novel bivalent and internalizing strategy to control monovalent radiotracers, and the clinically applied 18F-FDG, to generate data that may motivate further translational development of Vanco- PEG-DFOB for delineation of sites of infection. Importantly, this discovery platform can be adapted for other microbe-binding compounds to expand utility to a wide variety of infections.

NIH Research Projects · FY 2024 · 2024-09

Understanding the pathogenesis of cerebral small vessel disease (CSVD) and vascular contributions to dementia (VCID) is increasingly important to help protect the cognitive and mental health of an aging population. Recent technological advances now permit us to measure thousands of proteins and metabolites simultaneously in body fluids including cerebrospinal fluid (CSF), and single cell and spatial transcriptomics reveal tissue pathology at unprecedented resolution. Leveraging these new technologies to investigate CSVD and VCID will help to unravel the complex and heterogeneous mechanisms underlying these diseases. Here we take advantage of three resources led by our institution to best pursue these investigations. The first resource is a large collection of CSF samples from the Washington University Knight Alzheimer’s Disease Research Center (Knight-ADRC) and Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohorts. The second resource is a collection of human brain tissue specimens from these same cohorts. The third is extensive neuroimaging and analytical pipelines that can identify dissociable patterns of white matter hyperintensities (WMH), which are a key neuroimaging feature of CSVD. By combining these resources together, our first aim is to identify specific CSF proteins and metabolites related to each of 5 different WMH spatial patterns (i.e., topographies). This approach is likely to identify both shared and separate molecular correlates for each of the WMH topographies, which differentiate vascular risk factors and Alzheimer’s disease related pathologies. We will also determine how identified CSF correlates of CSVD relate to the development of cognitive impairment. Our second aim is to sample 5 regions of the brain, based on each of the different WMH topographies, from Knight-ADRC and ADNI human brain specimens. These will then undergo single cell and spatial transcriptomics, as well as further analysis using a vessel enrichment technique. We will relate these transcriptional data to premortem imaging and postmortem histopathology features from each specimen. The third and last aim is to perform a parallel transcriptomic analysis in rodent models of hypertension and cerebral amyloid angiopathy, both without and with treatment. Comparing rodent data to the human results will shed light on the validity of these rodent models for understanding CSVD in humans and may potentially reveal specific molecular mechanisms that underlie these diseases. We intend to use the results from all three aims to identify potential biomarkers and druggable targets. We are strongly committed to sharing all of the data produced by these efforts openly, and collectively hope that they will lead to a clearer mechanistic understanding of CSVD and VCID.

NIH Research Projects · FY 2024 · 2024-09

ABSTRACT This is a request to support the inaugural Nerve SPACE (Setting Priorities to Advance Clinical and Research Efforts in Nerve Injury) Conference, which will be hosted at Washington University Medical Center in St. Louis, MO in Q2 2025. Washington University has a distinct history of innovation and achievement in nerve injury and reconstruction, with internationally-recognized experts tracing lineage to the nerve programs in Plastic Surgery, Neurosurgery, and Orthopaedic Surgery, and is therefore uniquely position to host the inaugural Nerve SPACE meeting. Function of the musculoskeletal system is suddenly disrupted by nerve injuries. To restore function of the musculoskeletal system, patients with nerve injuries are cared for by hand surgeons, orthopaedic surgeons, plastic surgeons, and neurosurgeons. This broad coalition of disciplines provides the opportunity to gather a diverse and inclusive group of perspectives on the diagnosis, prognosis, clinical care, and research priorities for nerve injuries. The purpose of the Nerve SPACE conference is to gather nerve surgeons, established and emerging researchers, and other stakeholders (therapists, physiatrists, neurologists, patient advocates, and industry contacts) to discuss current controversies and future directions for clinical care and research in peripheral nerve injury. There will be an emphasis on open discussions, forward thinking, exploring cutting-edge findings, and building consensus.

NIH Research Projects · FY 2025 · 2024-09

ABSTRACT Heterotopic ossification (HO) is a condition involving pathologic bone formation in extra-skeletal soft tissues (e.g. tendons, ligaments, muscle) which can occur following orthopaedic surgeries or injuries such as high impact trauma and burns. There is an unmet clinical need to develop effective therapies to treat HO, particularly at early stages post-injury. In this proposed project, our objective is to explore small RNA targeting approaches (microRNA, siRNA) in a clinically relevant mouse model of trauma-induced HO to: i) develop and test new nanoparticle-based strategies to treat this debilitating condition, and ii) advance our understanding of the mechanisms driving HO and identify new potential therapeutic targets. From an unbiased microarray study to identify microRNA (miRNA) expression signatures in developing long bones, we identified miR-138 as being differentially-expressed in distinct regions of the growth plate. We subsequently showed that miR-138 has bone inhibitory function, including the ability to suppress HO in an established trauma-induced HO mouse model. Additionally, we demonstrated that a major mechanism by which miR-138 inhibits osteogenesis is by targeting and suppressing the cytoskeletal regulator, RhoC. We subsequently showed that direct inhibition of RhoC could also inhibit osteogenesis. Whether or not knockdown of RhoC alone can also dampen trauma-induced HO in vivo has yet to be investigated. Inflammation also plays a critical role in HO formation. Pilot data from our group show suppression of IL- 1-induced catabolic genes by either miR-138 over-expression or RhoC inhibition. In addition, p65 (a transcription factor component of the NF-kB complex and an important regulator of inflammation) is another reported target of miR-138, the function of which has not yet been examined in the context of HO. Taken together, we hypothesize that strategies to modulate miR-138 activity (and its downstream targets) will result in suppression of trauma-induced HO, including associated inflammation and pain, and also inform new mechanisms regulating this pathologic process. Two specific aims are proposed to address our hypothesis. Specific Aim 1 is focused on developing a small RNA targeting approach to suppress HO. The effects of over-expressing miR-138 or siRNAs targeting RhoC and p65 will be tested in the trauma-induced HO mouse model. Nanoparticle-based technology will be utilized to enhance translational RNA-targeting capabilities. In Specific Aim 2, a multi-omics approach will be used to determine the effects of nanoparticle treatments and how genetic-based over-expression of miR-138 in specific cell types can suppress HO. These studies will advance our knowledge on cellular processes driving HO, and provide evidence to support new therapeutic approaches, involving small RNA nanoparticle targeting, as a promising treatment for HO.

NIH Research Projects · FY 2024 · 2024-09

Degeneration of the intervertebral disc (IVD) is associated with changes to tissue composition and structure that include a loss of IVD height, decreased water content and decreased cellularity. Therapies based on supplementing degenerated IVD with mesenchymal stem or progenitor cells (MSC) have been widely explored for MSCs’ ability to secrete factors that contribute to cell survival, tissue repair and blunted inflammation. However, cells delivered without a carrier have short residence times in the tissue and are associated with a limited ability to repair the tissue. Strategies that promote MSC survival and localization in the IVD, such as injectable cell carriers and the addition of growth factors to promote MSC survival and biosynthesis are important to enable the true potential of cellular repair strategies. We aim to develop injectable, cell adhesive and growth factor presenting alginate hydrogels that unlock the reparative potential of MSCs to repair the disc. Many engineered cell carriers seek to reproduce the presence of cell-adhesive sites in the native extracellular matrix (ECM), by including full-length ECM proteins or short cell-adhesive peptides. Natural ECM also sequesters growth factors, including Insulin Like Growth Factor 1 (IGF-1) which promotes MSC survival and drives matrix synthesis by cells endogenous to the IVD. We propose to modify alginate gels to present both integrin-binding cyclic RGD peptides as well as tethered short peptides that mimic IGF-1. We hypothesize that combined presentation of cyclic RGD and IGF-1 mimicking peptides from MSC-encapsulating alginate gels will protect the MSC from apoptosis and inflammation in the hostile environment of the degenerative IVD, and enhance MSCs’ ability to promote survival and production of healthy ECM by resident cells of the IVD. We will test this hypothesis with in vitro studies of MSCs encapsulated in optimized peptide-modified alginate carriers, co-cultured with primary cells derived from human degenerative IVDs. We will also perform in vivo studies of human MSC encapsulation in optimized peptide-modified alginate carriers for transplantation into degenerated lumbar IVDs of the RNU rat. We expect the delivery of gel-encapsulated MSCs to induce IVD repair through activation of both cell adhesive and IGF-1 signaling pathways that promote MSCs’ secretion of cytokines for new ECM synthesis and blunted inflammation. Measures of IVD quality and single cell RNAseq will be obtained in the degenerated and treated rat IVDs to reveal the key populations and subpopulations of host cells that mediate pathology in IVD degeneration and those that are altered in response to MSC therapy.

NIH Research Projects · FY 2024 · 2024-09

Cancer predominantly affects the elderly, with a significant incidence of breast cancer in women aged 50-70. While cell mutations contribute to tumorigenesis, age-related changes in the tumor microenvironment, particularly in cancer-associated fibroblasts (CAFs), which themselves are diverse subsets with distinct roles, including inflammatory, vascular, and myofibroblast CAFs (iCAF, vCAF, and myCAF, respectively)2, may play a crucial role. Importantly, CAF subsets display substantial variability between different tissues and even within the same tissue3. Our study identifies senescent CAFs (senCAFs) as key players in breast cancer progression. In exciting new data we find that 1) senCAFs are frequently found in DCIS where they predict recurrence and in triple negative breast cancer (TNBC), estrogen receptor positive (ER+) BC, and Her2/Neu+ BC. 2) senCAFs are restricted to the myCAF population, raising the possibility that they are a developmental endpoint and do not simply appear stochastically in response to tissue level stress. 3) Depletion of senCAFs significantly reduces primary tumor progression and metastasis. 4) senCAFs modify the biophysical features of the extracellular matrix (ECM), which can impact host immune responses and tumor progression3. 5) senCAFs modify NK cell killing activity, which supports tumor growth. Together, these data lead to our hypothesis that senCAFs alter the biophysical properties of the ECM and immune responses to increase tumor growth and metastasis. To address this exciting hypothesis, we will use state of the art immunological and biophysical techniques in novel genetically engineered mouse models (GEMM) that we have built and human BC specimens in the following Aims. 1) Determine the organ specific effects of senCAFs on metastatic BC progression; 2) Determine how senCAFs impact ECM dynamics and tumor cell migration; and 3) Determine the impact of senCAFs on NK cell function and BC tumor progression. Our study on senCAFs, a novel component of the breast cancer microenvironment, may uncover critical mechanisms in breast cancer progression, guiding the development of immunotherapeutic and senolytic strategies.

NIH Research Projects · FY 2024 · 2024-09

ABSTRACT Down syndrome (DS), the most common genetic cause of intellectual disability, accounts for ~30% of all moderate-to-severe IDD cases, with ~5,500 new individuals diagnosed with DS each year in the United States. DS is associated with varying degrees of cognitive impairment from infancy onward, yet progress has been very limited in understanding the relationships between neurodevelopment in DS and deficits in function. While clear structural brain differences and altered functional connectivity have been observed in DS at older ages, limited knowledge of infant brain development in DS hampers understanding of the relationship between brain differences and early delays, as well as the impact of disrupted development of neurocircuitry on later function. Infant brain imaging studies are needed to clarify mechanisms that could guide novel interventions during a highly plastic stage of neurodevelopment and to identify biomarkers that could inform the personalization of DS treatment and enhanced outcomes. In-depth characterization of DS-associated developmental differences in neural circuit structure and function is also key to evaluating a range of emerging pharmacologic therapies and genetic modulators that show promise for improving long-term function. To address these gaps, our team proposes to complete deep phenotyping and neuroimaging in a DS infant cohort in response to RFA-OD-24-003, which articulates the plan for multiple sites to collaboratively assemble a lifespan cohort of individuals with DS. Here we propose to leverage the Infant Brain Imaging Study Network (IBIS), a multisite, multidisciplinary team with >15 years’ experience in infant recruitment and collection of longitudinal behavioral and neuroimaging data in typically developing infants and infants with Autism spectrum disorder (ASD), DS, and Fragile X Syndrome. Our specific aims are: 1) To collect multimodal neuroimaging, including structural and functional MRI, as well as EEG, in a cohort of 100 infants with DS and 50 typically developing controls at ages 6, 12, and 24 months; 2) to perform concurrent, longitudinal deep phenotyping on these infants in key developmental domains of cognition and adaptive function, and 3) to collect data characterizing variation in early social communication in these infants that would advance early risk assessment for ASD, which occurs in ~15% of children with DS. Our team will leverage IBIS’ expertise in ASD-relevant phenotyping to include standardized clinical measures as well as dimensional research measures allowing more refined characterization of social attention and language. Data will be collected on medical comorbidities, sociodemographic information, and family environmental factors, along with biospecimens for future genetic analyses. Data will be accessible to the scientific community and allow novel analyses to characterize the nature and timing of altered neurodevelopment in DS, as well as establish a richly phenotyped cohort for future longitudinal studies elucidating relationships between infant brain and behavioral development and long-term outcomes.

NIH Research Projects · FY 2025 · 2024-09

PROJECT SUMMARY/ABSTRACT Children with cancer in low-resource settings face a survival rate of only 20%. Clinical deterioration, defined as the worsening of patient status that requires clinical teams to recognize and respond in a coordinated fashion, remain a major cause of childhood cancer mortality globally. Interdisciplinary communication is essential to high-quality cancer care, especially during high-acuity events such as clinical deterioration. Despite knowledge that high quality interdisciplinary communication improves patient care and outcomes, we lack an understanding of specific modifiable determinants of communication quality and appropriate, usable, and measurable communication interventions. This is particularly true in low-resource settings. We have previously developed a valid, reliable, multilingual measure of communication quality during clinical deterioration and have conceptualized that communication structure and quality interact to directly impact the quality of childhood cancer care. The goal of this proposal is to develop and test a bundled multilevel intervention that responds to modifiable determinants of interdisciplinary communication quality and structural communication patterns in low-resource pediatric oncology hospitals to improve communication and care delivery. To accomplish this goal, we will engage clinicians and hospitals in low-resource settings. In Aim 1 we will identify the relationship between communication structure and quality in the care of children with cancer. We will conduct a cross-sectional social network analysis from 10 high-quality communication and 10 low-quality communication hospitals as determined by previous work. In Aim 2, we will develop a multilevel intervention to improve communication quality in low-resource hospitals. We will conduct a sequential mixed methods study using quantitative data from Aim 1 supplemented by qualitative interviews with clinicians. Following this, we will engage a global panel of experts in communication and clinical care to conduct implementation mapping, which will develop and prioritize an intervention to address common communication challenges. In Aim 3 we will conduct a cluster randomized control trial to test the feasibility and preliminary effectiveness of this multilevel intervention to improve communication quality in low-resource hospitals. We will test the identified intervention bundle at 8 low-resource hospitals. Our primary outcome will be the change in communication quality score, and we will also assess the feasibility, acceptability, and appropriateness of the intervention among frontline clinicians. When complete, this work will improve interdisciplinary communication and clinical outcomes for children with cancer in hospitals of all resource levels, thus advancing health equity globally.

NIH Research Projects · FY 2024 · 2024-09

Project Summary The afferent neurons of the eighth cranial nerve transmit information from the cochlea and vestibular organs to the brainstem. These neurons can be lost following damaging noise exposure, ototoxic injury, or as a consequence of normal aging. Once lost, afferent neurons do not regenerate, and their depletion can result in permanent hearing and balance deficits. In the case of hearing, clinical strategies to restore sensory function, such as cochlear implants, require survival of a sufficient number of spiral ganglion neurons. Unfortunately, there is currently no practicable method for replacing lost spiral ganglion neurons. Although the mammalian cochlea lacks the ability to regenerate neurons, the spiral ganglion contains a population of cells that express Nestin, which is widely regarded as a marker for neural stem cells. Studies conducted in mice have demonstrated that these Nestin-expressing cells do not divide once the cochlea has matured, and the signaling molecules that regulate their proliferation are not known. One factor that hinders the study of neurogenesis in the cochlea is that the cell bodies of cochlear afferents and Nestin-expressing cells are housed within bone in the inner ear and are not visually or experimentally accessible in living mammals. The task of developing methods for neuronal replacement in the inner ear would be greatly facilitated by the introduction of an appropriate model system to identify the basic cellular signals that permit ongoing addition and spontaneous regeneration of afferent neurons. The objective of the present proposal is to establish the posterior lateral line (pLL) ganglion of larval zebrafish as a model system for the study of neuronal repair and replacement. The pLL ganglion is comprised of ~50 neurons, which can be easily visualized in living animals. Current data indicate that about five new neurons/day are added to the pLL ganglion, but the identities of neural precursor cells and the factors that regulate their proliferation are not known. We have found that cells in larval pLL ganglion express two markers for neural precursors: Nestin and NeuroD. Moreover, expression of these two markers occurs in spatially distinct regions, suggesting two domains within the pLL ganglion that possess progenitor cells. Our studies will determine the contributions of each population to the process of ongoing neurogenesis in the pLL ganglion and reveal whether proliferation of either (or both) cell types is enhanced following ablation of a subset of afferent neurons. We will also quantify expression levels of Nestin and NeuroD within the ganglion as function of age to define the contribution of each cell type to the process of neuronal addition and regeneration. Finally, we will evaluate the function of macrophages in neurogenesis and regeneration of pLL ganglion neurons. Experiments will determine whether macrophages are activated by neuronal injury and will resolve whether they help promote the proliferation of progenitor cells. The data generated by this project will identify the factors that regulate production of sensory afferents and may reveal potential strategies for inducing proliferation of resident progenitors and differentiation of new neurons in the mammalian inner ear.

NIH Research Projects · FY 2025 · 2024-09

PROJECT SUMMARY Depression and anxiety are associated with alterations in brain networks supporting emotion processing and regulation, including attention (dorsal attention [DAN], ventral attention [VAN]), arousal and focus (cingulo- opercular [CON], saliency [SAL]), and self-regulation (default [DMN], frontoparietal [FPN]) networks. These networks undergo substantial development during the preschool years, a critical stage for developing self- regulation. Developing self-regulation involves learning how to distinguish specific negative emotions (e.g., sadness, fear, and anger). How caregivers react when their child expresses negative affect theoretically shapes how the neural representations of negative emotions develop, however this has not been formally tested. Further, a separate body of work shows that increased negative affect during the preschool period is a risk factor for later depression and anxiety. Together, this suggests a reinforcement model linking these two risk factors: increased expression of negative affect in the child elicits a caregiver response, which either scaffolds emotion learning or not. If the caregiving response is consistently negative, this results in the brain failing to develop separable concepts for distinct emotion categories, resulting in increased distress when faced with these emotions in the future. The principal goal of this study is to test this reinforcement model of how negative affect and caregiving interact to alter brain and emotional development, conferring risk for depression and anxiety. In Aim 1, I will characterize emotion processing development (activation and gaze to negative emotions) across the preschool period. In Aim 2, I will fit a reinforcement learning model, testing negative caregiving as a moderator of developing distinct negative emotion concepts. Finally in Aim 3, I will test if frequency of negative affect expression influences these associations. The department of Psychiatry is highly supportive of my transition to faculty and has offered a faculty position—Assistant Professor on the Investigator (tenure) Track—that is not contingent on the receipt of the DP5 grant and with 95% of my effort dedicated to research and a startup package tailored to my needs. I am also more than prepared for early independence. I have spent my entire research career independently studying the neurobiological etiology of anxiety and depression in collaboration with my mentors. Each of my first author papers builds on what was learned in the previous paper, innovating either conceptually or methodologically. I also have formal training and extensive experience in mentoring, training, management, grant-writing and data collection have all the necessary skills to run the complex and collaborative projects that comprise my independent program of research. In sum, my scientific and technical expertise, my accomplishments, and my leadership, mentorship, and management skills are perfectly suited to launch my independent research program and carry out both the proposed work and my long-term research goals.

NIH Research Projects · FY 2025 · 2024-09

Project Summary/Abstract Glenohumeral osteoarthritis (OA) can be as debilitating as hip or knee OA, and in the US, shoulder arthroplasty rates for OA are rising more rapidly than hip and knee arthroplasty. Yet few studies have investigated glenohumeral OA risk factors, resulting in insufficient insights to guide evidence-based prevention and treatment strategies. For OA at other joints, many risk factors are known, including sex, occupation, and genetics, but effects can vary considerably by joint type. Therefore effects on glenohumeral OA cannot be inferred without studies specific to the shoulder. While occupational risk factors for shoulder pain have been identified, there has been limited investigation of factors that specifically effect glenohumeral OA. Moreover, the genetics of glenohumeral OA is an unexplored area. Shoulder arthroplasty is also strongly correlated with hip and knee arthroplasty, and is known to be more common in patients with a history of shoulder instability. But estimates of the absolute risk of shoulder arthroplasty and how this risk differs across patient populations has not been well-defined. This information could improve patient counseling, and could indicate opportunities for early evaluation of OA in high-risk patient groups. Our central hypothesis is that glenohumeral OA results from a mix of modifiable (occupation) and non-modifiable factors (age, sex, genetics), and that these factors can be used alongside surgical history to produce informative risk predictions for glenohumeral OA. As no sufficiently large studies systematically capture radiographic measures of glenohumeral OA, our study will focus on shoulder arthroplasty as a measure of end-stage glenohumeral OA. Our objectives are to determine associations of occupational exposures with OA-related shoulder arthroplasty risk (Aim 1), identify genetic variants associated with risk of OA-related shoulder arthroplasty (Aim 2), and develop prediction models for 5- year and 10-year risk of OA-related shoulder arthroplasty (Aim 3). Across all aims we will use the UK Biobank (UKB), a population-based, 500,000-person cohort with more than a decade of prospectively linked hospital records capturing diagnoses and procedures, including >1200 OA-related shoulder arthroplasty cases. For Aim 1, we will link a novel job exposure matrix to UKB job titles to measure shoulder-specific occupational tasks. For Aim 2, we will combine whole-genome sequencing data available in UKB and the US-based All of US cohort to conduct an innovative sequencing-based genome-wide association study for OA-related shoulder arthroplasty. For Aim 3, we will leverage both the UKB and the US Healthcare Cost and Utilization Project to develop prediction models for us in both the general population, and specific high-risk patient populations. An understanding of glenohumeral OA risk factors is critically needed to allow informed design of prevention approaches. As shoulder arthroplasty is strongly correlated with OA at other joints, better understanding of genetic influences of glenohumeral OA can provide deeper insights regarding OA etiology. Findings from this study can enable better prediction of glenohumeral OA, improving patient counseling in the future.

NIH Research Projects · FY 2025 · 2024-09

Effective treatment schemes have reduced breast cancer mortality, but precise identification of women at increased risk of developing breast cancer, to personalize screening and preventive interventions, accordingly, is a major outstanding challenge. This urgent clinical need is most prominent among Black women, in view of their higher breast cancer mortality than White women. Studies have consistently shown the potential of artificial intelligence in the form of deep learning (DL) to elucidate novel mammographic signatures highly predictive of breast cancer. However, currently available DL models were developed in mostly White populations, and therefore, may generalize poorly in Black populations that would benefit from risk-based tailored screening and preventive strategies. Moreover, most related DL studies rely on digital mammography (DM) images, although digital breast tomosynthesis (DBT) has rapidly replaced DM in the US. These studies also paid limited attention to model interpretability, which is critical for clinical translation of DL models. We will leverage a unique multi-site resource of screening data from Black women (4507 cases; 90,701 controls; with 5-year follow-up) and state-of-the-art DL and medical imaging informatics tools, with the aim to enable accurate long-term (i.e., 5-year) breast cancer risk assessment for Black women. We will accomplish this through developments of DL imaging signatures of breast cancer risk with the new standard of breast cancer screening, DBT; thorough evaluations of their clinical utility in a multi-site setting; and deployment/dissemination activities to enable further evaluations and refinements based on feedback. We propose three aims. SA1 will develop a DBT-driven breast cancer risk score via DL and its combination with the clinical Black Women’s Health Study (BWHS) risk model into a hybrid breast cancer risk prediction tool. SA2 will perform independent clinical utility evaluations of our breast cancer risk prediction tool. SA3 will focus on translational innovation, by developing the deployment framework and disseminating our tools, knowledge, and resources. Our study will be the first of its kind on computational mammographic signatures of breast cancer risk among Black women. We anticipate that the successful completion of our aims will provide a novel tool for accurate long-term breast cancer risk assessment among Black women, extensive multi-site validation data and a complementary deployment/dissemination framework to enable further evaluations in research settings. We expect that the groundbreaking outcomes of this project will have a major impact on advancing personalized risk assessment for Black women, which, in turn, will lay the foundation for enhanced precision breast cancer screening and prevention strategies.

NIH Research Projects · FY 2024 · 2024-09

Chronic postsurgical pain (CPSP) is a major healthcare burden, affecting nearly 20% of patients undergoing major surgery. CPSP is associated with diminished quality of life, mood disturbances, functional impairment, and increases the risk of opioid use disorder. Considerable research suggests that a combination of somatosensory, immune, affective and cognitive mechanisms contribute to CPSP, and that CPSP phenotypes are highly heterogeneous, even after identical surgical procedures. However, most prior research has explored peripheral or central mechanisms in isolation, preventing an integrated insight into underlying biological factors that drive these distinct clinical phenotypes. Preclinical models of CSPS have also failed to capture this phenotypic heterogeneity or meaningful clinical outcome measures, significantly limiting forward translation of basic discoveries. As a result, current strategies for predicting, preventing and treating CPSP are extremely limited. To address this need, we have developed the IMPETUS program that draws expertise from pain neurobiology, clinical pain research, clinical psychology, cognitive neuroscience, immunology, proteomics, genomics, transcriptomics, bioinformatics, machine learning, and pain medicine. Our goal is to gain integrated mechanistic insights into peripheral and central biological processes that contribute to CPSP, and to understand how these processes contribute to CPSP heterogeneity. Aim 1. Characterize peripheral neural and immune mechanisms contributing to CPSP. In patients with CPSP subsequent to abdominal or genitourinary surgery (n=220) and contemporaneous controls (n=100), we will characterize somatosensory profiles of mechanical and thermal sensitivity, the neural and immune milieu at the cutaneous site of injury, and circulating immune host profiles, and compare them with correlates across the same domains in a mouse model of laparotomy. Aim 2. Characterize cognitive and affective mechanisms contributing to CPSP. In patients with CPSP and controls, we will use granular longitudinal data collection methods to characterize affective, cognitive, and activity/sleep measures of CPSP, and compare them with animal model correlates across these domains, using translational outputs of amotivation, punishment-sensitivity, reversal learning task, and actigraphy. Aim 3. Identify and back-translate mechanism-based CPSP phenotypes. Using state-of-the-art machine learning approaches applied to multidimensional data generated in Aims 1 and 2, we will identify discrete CPSP phenotypes, and recapitulate them in animal models for improved translatability. We expect the IMPETUS program to 1) identify distinct somatosensory, neural, immune, affective and cognitive mechanisms that contribute to distinct CPSP phenotypes and explain inter-patient heterogeneity, with cross-species validation; 2) Characterize distinct phenotypic clusters within CPSP to inform personalized patient care and stratified clinical trials for CPSP interventions; and 3) Develop animal models that recapitulate specific clinical phenotypes of CPSP to accelerate for mechanistic exploration and novel therapeutic development.

NIH Research Projects · FY 2025 · 2024-09

Project Summary/Abstract This proposal outlines the five-year research and career development plans for the PI, Stephen P. Persaud, MD, PhD, who is preparing for a career as an academic physician-scientist. Dr. Persaud completed his MD and PhD in immunology in 2015 at Washington University School of Medicine (WUSM), then completed his residency in Clinical Pathology in 2018 at Barnes-Jewish Hospital as part of the Pathology Physician Scientist Training Program. During his residency elective time, he began postdoctoral research in the lab of John DiPersio, MD, PhD, in the Oncology Division of the Department of Medicine at WUSM. Dr. DiPersio is an expert in allogeneic hematopoietic stem cell transplantation (allo-HSCT), normal and malignant hematopoiesis, and cellular immunotherapy, and has an outstanding track record of training successful physician-scientists. The exemplary scientific resources and environment provided by the DiPersio lab and WUSM, combined with the mentoring and training plans described herein, will enhance Dr. Persaud’s research program and advance his progress towards becoming an independent investigator. The long-term goal of the proposed research is to optimize HSCT conditioning, stem cell mobilization, and therapeutic gene editing to safely enable transplantation for non-malignant hematologic diseases, particularly sickle cell disease (SCD). Dr. Persaud published the first study showing that CD45- or cKit-targeted antibody-drug conjugates (ADCs) combined with Janus kinase 1/2 (JAK1/2) inhibitors could enable fully MHC-mismatched HSCT in mice. This work was the DiPersio lab’s first contribution to the antibody-based conditioning field and gave rise to several successful projects, including 1) development of fully myeloablative ADCs suitable for HSCT conditioning in the context of leukemia therapy, 2) the combination of anti-CD47/cKit antibodies with JAK1/2 inhibitors for toxin- free allo-HSCT conditioning, and 3) development of a novel streptavidin-based platform for rapid ADC production and screening. Dr. Persaud will build on this body of work in this proposal via two Specific Aims, which focus on overcoming the major hurdles to autologous gene therapy for SCD. In Aim 1, he will evaluate novel stem cell mobilization regimens combining VLA-4 and CXCR4 inhibition and assess their ability to generate a sufficient quantity and quality of stem cells for autologous gene therapy compared to standard-of- care regimens. In Aim 2, Dr. Persaud will optimize toxin-free conditioning with anti-CD47/cKit antibodies for transplantation and cure of SCD, including the development of novel bispecific CD47 x cKit antibodies. Collectively, these studies will explore the basic biology and translational potential of several novel approaches for improving the safety and efficacy of HSCT. Although this proposal focuses on autologous gene therapy for SCD, the work has important implications for both autologous and allogeneic transplantation for malignant and non-malignant diseases alike. Finally, the research will advance Dr. Persaud’s primary goal of building a research program dedicated to maximizing the therapeutic benefit of HSCT while minimizing injury to the host.

NIH Research Projects · FY 2025 · 2024-09

PROJECT SUMMARY There is a critical need for more effective treatments for metastatic and relapsed neuroblastoma (NB), the most commonly diagnosed extracranial solid cancer in children and the most common cancer in infancy. Following years of advancement of multimodal therapies, 60 % of high risk NB will recur after treatment, resulting in a 5% survival rate at 5 years. Conventional regimens now include targeted radiotherapy to the norepinephrine transporter (NET). This is a well-validated biomarker expressed in >90% of patients, and is targeted by 131I-MIBG – a beta particle emitting NET substrate. SSTR2 is another important neuroendocrine specific target, which is also highly expressed in >70% of NB. FDA-approved SSTR2 radiopeptides, 68Ga/177Lu-DOTA-TATE have showed some efficacy in investigational use in pediatrics. However, both 131I-MIBG and 177Lu- DOTA-TATE are low linear energy transfer, beta particle-emitting agents, which lack the capacity to ablate cancer cells or occult small lesions. 131I-MIBG treatment only achieves a long-term response in about 30% of NB patients, which is far lower than NET expression incidence. High linear energy transfer emissions have the capacity to eliminate microscopic occult disease sites, while sparing distant tissues from the long path lengths of conventional beta-emitting treatments. In this application we put forwards a combination treatment strategy with novel ligands to address multiple failure points of conventional targeted radiotherapy for this devastating disease. To NET, we target 77Br-MBBG (a highly chemically stable, auger emitting meta-bromobenzylguanidine) and to SSTR2 we have developed 227Th-L804-LM3 (a best-in-class Thorium-227 alpha emitter- conjugated antagonist for SSTR2). These high LET agents will selectively kill cancer cells with definitive anticancer effects; and the synergistic elimination of low expressors of either target will be compensated by the combination approach. We deploy and characterize these next generation agents to advance NB care in standard xenografts and advanced patient derived models of NB. We monitor treatment efficacy of 77Br-MBBG, 227Th-L804-LM3 and their combinations, and compare to conventional 131I-MIBG and 177Lu-DOTA-TATE treatment. We monitor tumor response; target expression using quantitative molecular imaging analogs; DNA damage and repair; and genomic profiles of NB in the de novo and post-treatment states. Through these studies, we anticipate to optimize novel treatment approach that can undergo near term translation at Washington University in St. Louis Children’s Hospital.

NIH Research Projects · FY 2024 · 2024-09

Autosomal dominant tubulointerstitial kidney disease caused by uromodulin mutations (ADTKD-UMOD) is one of the most common hereditary kidney diseases. It represents as many as 25% of patients with inherited kidney disease, after exclusion of polycystic kidney disease and Alport syndrome. ADTKD is characterized by progressive renal fibrosis, and currently there is no treatment. To develop targeted therapies, by using CRISPR/Cas9, we have generated the first ADTKD-UMOD mouse model harboring a leading human UMOD deletion mutation. UMOD is largely synthesized and secreted by tubular cells of thick ascending limb (TAL). Our mouse model shows that autophagy deficiency in TALs leads to increased accumulation of mutant UMOD protein-the root cause of the disease, eventually causing TAL cell death and renal fibrosis in ADTKD. The goal of this R56 award is to delineate the molecular mechanism regulating autophagy in ADTKD. The proposed study will pave the way to develop new therapeutic strategies for ADTKD patients.

NIH Research Projects · FY 2025 · 2024-09

Abstract For more than a decade the importance of the microbiome and its role in health and disease has been appreciated, yet the virome (the viral component of the microbiome) has remained understudied. Physiologic changes during pregnancy and the postpartum period (often overlooked periods of the lifespan) include dramatic adaptations in immune response that provide a unique opportunity to study and understand the dynamic interplay between the virome and host. Both systemic and local modifications in innate and adaptive immunity have been described, characterizing an “immunological clock” of pregnancy. These programmed changes in immune response are critical for pregnancy success, providing a balance between fetal tolerance and effective protection from pathogens, including viruses. Individual viruses that cause adverse pregnancy outcomes have been frequently studied, for example those that cause more severe infection during pregnancy and those that cause congenital infections. However, the complex communities of the virome (in this case defined as all the viruses that infect human cells) have largely remained unexplored. We hypothesize that the dynamic, programmed changes in immune response through pregnancy and postpartum will alter the interactions between virome and host, revealing important underlying biology of the virome-maternal-fetal unit. To test this hypothesis, we will prospectively collect longitudinal samples from the pregnancy, delivery, and postpartum periods in a racially diverse cohort of 100 subjects enrolled at two sites to monitor the virome in tandem with local and systemic immune responses.

NIH Research Projects · FY 2025 · 2024-09

ABSTRACT The gut microbiome (GM) strongly influences human health, playing critical roles in immune priming, nutrient metabolism, and pathogen exclusion. During infant and child development, the GM undergoes a systematic turnover of species until reaching an adult-like state. The equilibrium of the gut ecosystem can be disrupted by perturbations, such as antibiotic usage and inflammatory exposures, causing significant decreases in microbial diversity and aberrant physiological processes, sometimes with lifelong implications. However, the mechanisms underlying the resilience of the GM to shifts or perturbations are not well understood. The gut virome is dominated by bacteriophages (phages), which play crucial roles in shaping bacterial communities through predation and horizontal gene transfer. Viruses can also directly interact with human cells to influence gut physiology. Herein, we hypothesize that altered viral communities are both symptoms of and contributors to human disease, as gastrointestinal perturbations drive phage induction and subsequent virus-bacteria and virus-human interactions which impact human health. Accordingly, we propose to study virus-bacteria-human dynamics during antibiotic exposure and inflammatory diseases, leveraging over 70,000 banked patient stools from four cohorts with well- curated clinical metadata. The rationale implicating a functional role for viruses in human gut health is that changes in the abundance of specific viruses targeting certain bacterial populations are frequently observed in perturbed GM states. These include antibiotic exposure and intestinal inflammatory conditions for which there is no clear bacterial etiological agent, such as inflammatory bowel disease in adults and necrotizing enterocolitis in preterm infants. Our central motivation is to provide a comprehensive analysis of human gut ecology during dramatic GM shift events that are consistently correlated with virome alterations. Understanding these alterations is critical for the design of virus-related diagnostic or therapeutic strategies to improve inflammatory disease outcomes and antibiotic-triggered GM imbalance. This will be achieved through two aims to: I) Define the interactions between viruses, bacteria, and human cells contributing to perturbation-associated shift events, and II) Determine the effects of host-associated perturbations on gut viruses and their contributions to the inflammatory responses in mammalian cells and GM-humanized mouse models. Our analyses are significant as they provide a systematic investigation of the relationship between GM perturbations and virome alterations in adult and pediatric populations. Our proposal is innovative in leveraging novel complementary technologies including high-resolution genomics, viral tagging of bacterial and human cells, and GM-humanized gnotobiotic mouse models to identify viral drivers of clinical outcomes. Our proposal is impactful in its goal to address basic, translational, and clinically relevant questions in functional virus-bacterial-human interactions related to human health and disease.

NIH Research Projects · FY 2024 · 2024-09

PROJECT SUMMARY/ABSTRACT Up to half of depressed older adults do not respond to an initial antidepressant, and fewer than 20% achieve remission. Using a robust multi-site clinical trial network, we have completed two landmark randomized controlled trials (RCTs) showing that augmentation of current antidepressant with aripiprazole (ARI) or bupropion (BUP) results in a 29% remission rate in TRLLD. In response to RFA-MH-24-120, we will use this and other existing clinical trial data to design and evaluate a clinical decision support tool, the Biotype-assigned Augmentation Approach in Resistant Late-Life Depression (BAARD), to improve treatment selection using precision biomedical information. With integrated expertise in geroscience, psychopharmacology, cognition, molecular subtyping, neuroimaging, computational psychiatry, and qualitative research methods represented on our research team, we will use existing demographic, clinical, cognitive, genetic, proteomic, and high quality neuroimaging on ~700 participants to develop and test the BAARD tool. UG3 Phase Specific Aims: Design and Validate the BAARD Decision Support Tool. Aim 1, Yr 1: Develop the BAARD tool for treatment selection in TRLLD using data from two large multi-center trials (‘IRL-GRey’ & ‘OPTIMUM’) and the embedded biomarker study (‘OPT-Neuro’) (total N~700). Aim 2, Yr 2: Refine the BAARD biotype profile & analytic approach using data from individuals diagnosed with major depressive disorder (MDD) or treatment resistant depression (TRD) from the Canadian Biomarker Integration Network in Depression (CANBIND, N~200) and UK Biobank (UKB, N~2,400) studies, respectively. Go-no-go threshold for Yrs 1-2: To proceed to the proposed UH3 RCT phase (N=300), our BAARD tool must achieve a combined predicted remission rate of ≥46% in cross-validation. This corresponds to a balanced accuracy of ≥75% for remission prediction in test data and will be assessed at the end of Yr 1 and Yr 2. UH3 Phase Specific Aims: Test the BAARD Decision Support Tool in a Prospective RCT. Aim 3, Yrs 3-5: In the UH3 phase, we will randomize 300 adults aged ≥60 yrs with TRLLD (2:1) to BAARD tool- assigned treatment vs. randomized treatment assignment (1:1 ARI:BUP) and compare remission rates based on the Montgomery Asberg Rating Scale score (MADRS score<10) following 10 weeks of treatment. Hypothesis: The remission rate in the group treated with ARI or BUP based on BAARD predictions will be at least 17% higher than the remission rate observed in the randomly treated comparison group (e.g., 46% vs. 29%). Go-no-Go threshold for Yrs 3-5: The annual threshold for proceeding with the RCT will be based on participant enrollment milestones (first by end of Q9; 50% by end of Q12; 100% by end of Q15). Exploratory Aim, Yrs 4-5: Obtain stakeholder input on acceptability and appropriateness of BAARD and explore facilitators and barriers to implementation in future clinical trials, and eventually, routine clinical care.

NIH Research Projects · FY 2025 · 2024-09

PROJECT SUMMARY Alzheimer’s disease (AD), a progressive neurodegenerative disease causing memory loss, is the primary cause of dementia. Recent FDA approval of an amyloid beta-targeting medicine represents a significant advance in AD treatment, yet effective therapies for tau pathology remain crucial. Tau accumulation and neurofibrillary tangles are central to AD pathology and strongly correlate with cognitive decline and neuronal loss1. Therefore, strategies that seek to interrupt tau deposition and propagation may be effective treatments. Regions associated with tau accumulation2 in postmortem AD brains show reduced proteasome activity, suggesting impaired protein degradation may contribute to tau pathology. Thus, increasing proteasome activity to degrade tau may be an efficient therapy to reduce tau burden and neurodegeneration. The ubiquitin-proteasome system is negatively regulated, in part, by enzymes that remove the ubiquitin side chains from proteins targeted to the proteasome. Among these enzymes, the ubiquitin-specific protease 14 (Usp14) selectively acts on substrates, including tau, to reduce or prevent their degradation. This proposal tests an antisense oligonucleotide (ASO)-mediated approach to reduce Usp14 in the central nervous system, increasing proteasomal degradation of tau. ASOs are short, single-stranded DNA that bind to target mRNA to decrease or modify the protein expression through the recruitment of RNAse H. In recent years, ASOs have become valuable tools for understanding and treating neurodegenerative diseases, and improved chemistries and delivery methods have made ASOs safe and effective in multiple clinical trials3,4. Preliminary data show that Usp14-lowering ASO treatment activates the proteasome system and decreases total tau in neurons and tau transgenic mice. Using this effective tool, this proposal will assess the effects of proteasome activation on tau pathology and tau seeding in a mouse model of tau-mediated neurodegeneration. Aim 1 will test the effects of proteasomal activation via Usp14 lowering on tau pathology and gliosis in mutant P301S tau transgenic mice (PS19). I will intraventricularly administer Usp14- lowering ASOs to PS19 mice at early (3 months), mid (6 months), and late (9 months) stage pathology to evaluate neurofibrillary tangle formation, neuronal loss, gliosis, and potential off-target effects using immunohistochemistry, mass spectrometry, and ELISA assays. Aim 2 will investigate proteasomal activation's role in preventing tau seeding in vitro and its propagation in vivo. In vitro, primary neurons will be treated with GFP-labeled bioactive tau seeds, followed by Usp14-lowering ASO to activate the proteasome system. I will assess amount of GFP-labeled tau seeds and total aggregated tau to evaluate seeding efficiency. In vivo, wildtype mice will be injected with tau seeds and subsequently treated with Usp14-lowering ASO. The extent of tau propagation will be quantified by assessing the spread of endogenous tau aggregation beyond the initial GFP-labeled seed sites, comparing changes across treatment groups. Upon its successful completion, this project will determine if proteasomal activation via Usp14 targeting is an effective therapeutic strategy for AD.

NIH Research Projects · FY 2024 · 2024-09

Fentanyl and other synthetic opioids are killing thousands of Americans each year. The overall goal of this research is to better understand the role of the primary central noradrenergic system in fentanyl withdrawal. We have known for decades that increased locus coeruleus-noradrenergic (LC-NE) system activity is critically involved in both stress-induced increases negative affect and is potently modulated by withdrawal from opioids. However, there is extensive, long-term controversy over the contribution of the LC-NE system to opioid withdrawal-related behaviors. Critically, opioid withdrawal increases glutamate efflux into the locus coeruleus. This fundamental feature of opioid withdrawal was identified and rigorously studied for many years, generating potential therapeutic interventions that never reached the clinic. Study on this topic went largely quiet after lesions studies indicated an intact LC-NE system was not necessary for the withdrawal-induced place aversion or somatic signs of withdrawal. Despite these important findings, relatively little is known about afferent glutamatergic regulation of LC-NE neurons in opioid withdrawal-induced negative affect. We will determine whether a newly identified midbrain glutamatergic input to LC-NE neurons contributes to negative affective behaviors associated with opioid withdrawal. We have now identified a largely unstudied afferent projection to the LC from excitatory neurons in the ventral tegmental area (VTA), a region critical for processing reward and motivation. While projections from these glutamatergic VTA neurons to the nucleus accumbens and lateral habenula have opposing valences on aversion in mouse models, we hypothesize that VTA glutamate projections to the LC-NE system produce negative affect and will be modulated by opioid withdrawal. Our preliminary electrophysiology data suggests that this glutamatergic input to the LC amplifies other sources of glutamate. In this proposal, we begin by seeking to determine whether withdrawal from fentanyl selectively modifies this excitatory input the LC compared to other well-established excitatory inputs. Here, we will use brain slice electrophysiology and in vivo microdialysis to test the hypothesis that excitatory VTA-LC activity is selectively enhanced in opioid withdrawal. In the second aim, we will conduct behavioral studies modulating this excitatory VTA-LC projection to determine whether it is needed for natural avoidance behaviors that guide actions away from risk. Our preliminary data shows these behaviors that are amplified following fentanyl withdrawal. Together these experiments will generate previously unattainable information about fentanyl-induced plasticity in VTA glutamate inputs to LC-NE neurons and the negative affective behaviors these neurons generate. These studies will clarify function of the excitatory VTA-LC projection by determining 1) whether fentanyl withdrawal alters their input to the LC-NE system and 2) their role in fentanyl withdrawal-induced avoidance behaviors. This information will be critical for translational research targeting noradrenergic and/or glutamate systems in the treatment of opioid withdrawal and related neuropsychiatric disorders.

NIH Research Projects · FY 2025 · 2024-09

ABSTRACT The pathogenesis of postoperative delirium likely involves systemic inflammation, downstream neuroinflammation, and altered synaptic plasticity reflected by elevations in IL-6 and electroencephalographic (EEG) slowing. Furthermore, there are no known pharmacologic interventions for preventing postoperative delirium. Fluvoxamine is an antidepressant that could suppress neuroinflammation through sigma-1 receptor agonism. Fluvoxamine reduces prostaglandin synthesis and cytokine release from human blood. It is concentrates in the brain and neuroprotective via sigma-1 receptors. It improves survival in sepsis animal models and reduces clinical deterioration from COVID-19. Promise in the treatment of delirium is supported by a series of case reports of fluvoxamine treating delirium in older adults and/or intensive care unit. It is not clear whether suppressing neuroinflammation is a viable pathway towards mitigating delirium severity. Furthermore, it is unclear whether fluvoxamine is a feasible pharmacologic intervention for mitigating delirium risk, given societal stigma against antidepressants as well as side effects of nausea and potential drug-drug interactions. To evaluate the safety and feasibility of a multisite investigation on perioperative fluvoxamine, we propose Mitigating Delirium with Fluvoxamine Treatment for Non-Cardiac Surgery (MD FluNCS): Feasibility Trials & Mechanistic Insights. This work will enhance our understanding of core pathogenesis of postoperative delirium in a population at risk for Alzheimer's disease and related dementias. With the rise in the aging population, we hope to provide an intervention to mitigate risk as well as translatable theragnostic biomarkers and approaches for future precision medicine. The investigation will lay the groundwork for a larger scale Phase 3 trial geared toward advancing long-term goal of improving public health and quality of life for those at risk of postoperative delirium and related sequelae.

NIH Research Projects · FY 2025 · 2024-09

PROJECT SUMMARY / ABSTRACT Hyperpolarized (HP) 13C pyruvate MRI is an emerging imaging modality that provides unique access to glucose metabolism in the brain, a pathway that is implicated in brain aging and neurodegeneration by 15O / 18F metabolic PET research studies from our group and others. Prior human HP 13C research has been restricted almost exclusively to scanners from a single vendor, because of need for specialized pulse sequences and hardware. In this R21 project, we propose to establish the feasibility and reproducibility of advanced HP 13C imaging of the human brain on a major underexplored clinical MRI platform (Siemens). Although we acknowledge that some prior HP 13C MR/MRI work has already been conducted on this platform, this will be the first study to use metabolite-specific echo-planar imaging (EPI) with spectral-spatial radiofrequency (RF) excitation, which is a highly advantageous approach for HP 13C studies and is the most popular method for human HP 13C MRI, according to a recent consensus review paper. This will also be the first HP 13C work in brain on Siemens. Thus we consider feasibility of state-of-the-art human HP 13C brain imaging on this platform as an important objective. In Aim 1, testing will first be conducted in vitro by imaging a human-scale 3D-printed Shepp-Logan bioreactor phantom that mimics the signal dynamics of human hyperpolarized 13C brain imaging studies. In Aim 2, we will evaluate the reproducibility of in vivo HP 13C pyruvate human brain imaging in a test group of cognitively unimpaired adults, recruited from our existing 15O / 18F metabolic PET study. Each subject will be scanned twice in succession during each imaging session, and regional and spatial comparisons will be made between runs. To clarify the overall focus of the project in this resubmission application, the main scientific objective is evaluating the reproducibility of HP 13C imaging of human brain in normal subjects, which has yet to be established. As an exploratory aim, topography of this pilot HP 13C pyruvate MRI data will also be compared against metabolic PET data from the same subjects, to help motivate future HP 13C pyruvate brain imaging research studies.

NIH Research Projects · FY 2025 · 2024-09

ABSTRACT We propose to study how the innate response to virus changes as children mature, which we theorize contributes to asthma remission. Although asthma is a chronic disease, its symptoms vary greatly based on the season, time of day, and age. Asthma seasonality is driven by respiratory virus outbreaks2, 3. Time-of-day variations arise from the circadian clock, which regulates lung remodeling after respiratory viral infection4-6. The least understood is why age affects asthma activity, and particularly why asthma exacerbations gradually resolve in 50% of children as they mature7, 8. Understanding the biological processes that cause asthma resolution in children could yield ways of promoting remission in all patients. We hypothesize that asthmatic children experience fewer asthma exacerbations as they age because they develop a pro-resolution response to viruses, preventing new type-2 inflammation and airway remodeling from forming with each new infection. We further hypothesize that circadian clocks operating within alveolar macrophages (AMs) and airway epithelial cells are critical for this pro-resolution response. Our hypotheses arise from observations that, in children, viruses become less potent at triggering asthma exacerbations as children mature. In mice, respiratory viral infections that produce chronic lung remodeling in juvenile animals fail to do so in adults. The protection afforded by adult age correlates with a blunted type 2 inflammatory response to viruses. AMs are required for adult protection from post-viral lung disease and exhibit a distinct transcriptional and immunophenotypic profile. Protection is also marked by reduced accumulation of dysplastic Krt17+ basal cells after respiratory viral infection. Finally, these age-related benefits are negated by circadian clock disruption, leading otherwise protected adult mice to develop chronic post-viral lung disease like juveniles. This project will clarify how the circadian clock mediates the adult age, pro-resolution response to viral asthma triggers. Proposed experiments in mice use Sendai virus (SeV) as a viral model of asthmatic lung remodeling and Alternaria alternata extract as an allergic model that serves as a comparator. We will employ complementary genetic and environmental methods to disrupt circadian clock function (clock gene Bmal1 deletion and chronic jet lag or CJL). Aim 1 focuses on how the adult-age AM clock promotes the resolution of viral inflammation. Aim 2 focuses on how the adult-age epithelial clock promotes the normal repair of viral airway injury. We will analyze antiviral function in airway cells from asthma remission patients for the first time. This project aligns with NIH research priorities and satisfies the recent Notice of Special Interest NOT-HL-22-043: Basic and Translational Research on Circadian Regulation of Heart, Lung, Blood, and Sleep Disorders.

NSF Awards · FY 2024 · 2024-09

Three-dimensional (3D) surface models are widely used in many domains, such as engineering, design, manufacturing, medicine, and entertainment. In many use cases, the surface models are obtained from curve inputs. For example, engineers traditionally construct an object by first defining its wireframe; designers routinely conceptualize new shapes by sketching curves; and doctors often create 3D models of organs by delineating the organ boundaries on 2D slices of an image volume. Crucial to these applications is the ability to reconstruct a complete surface from a set of sparse, un-organized, and possibly noise-ridden curve segments. This research will develop a suite of algorithms that offer such ability with improved efficiency, surface quality, and generality over existing methods. Ultimately, the project will make it easier for everyone - novices and professionals alike - to create 3D models by drawing curves. Curve inputs are particularly challenging for surface reconstruction due to their sparsity, imprecision, and lack of connectivity. This project builds on the success of recent variational methods for surface construction from sparse and noisy point clouds, and introduces new problem formulations, optimization strategies, and surface representations for generating surfaces from 3D curves. The research will extend existing variational methods in three significant ways: improved efficiency for large inputs and interactive applications; better surface shapes that leverage higher-order geometric information of curves; and a greater variety of outputs including piecewise-smooth surfaces, surfaces with open boundaries, and non-manifold surface networks. The project will also produce prototypes of interactive, curve-driven modeling software that complements existing modeling tools with the unique capability of direct surface generation from unorganized and error-laden curves. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.