Univ Of North Carolina Chapel Hill

NIH Research Projects · FY 2025 · 2023-08

Project Summary/Abstract This Mentored Patient-Oriented Research Career Development Award will provide a structured environment with expert mentorship to enable Dr. Wesley M. Jackson to develop as an independent investigator and future leader in the field of neonatology. Hypoxic-ischemic encephalopathy (HIE) is a common and often fatal disease in infants. Mortality or severe neurodevelopmental impairment in infants with HIE remain high, despite the widespread use of therapeutic hypothermia. As a result, there is an urgent, unmet public health need to develop adjuvant therapies to improve neurodevelopmental outcomes in this population. Caffeine has been shown to reduce brain injury in animal models of HIE and may offer neuroprotection in infants with HIE. However, caffeine has not been studied in the setting of HIE and therapeutic hypothermia in humans. Dr. Jackson proposes to develop a population pharmacokinetics (PK) model of caffeine in the setting of therapeutic hypothermia to characterize the effects of hypothermia on caffeine disposition (AIM 1). He will utilize dosing simulations to optimize the caffeine treatment regimen to achieve therapeutic levels (AIM 2). Finally, he will validate the optimal dosing regimen in an open-label trial of caffeine in 24 infants receiving therapeutic hypothermia for HIE (AIM 3). Dr. Jackson developed a multidisciplinary career development plan to develop skills in clinical pharmacology, population PK modeling, and trials operations. The combination of structured and rigorous coursework with practical training provided by the aims of this proposal will allow Dr. Jackson to develop the skills necessary to become an independent researcher and leader in the field of neonatology. To guide him through this academic development, Dr. Jackson has assembled an experienced mentorship team with expertise in clinical pharmacology, trials operations, and drug development. Upon successful completion of the proposed Mentored Patient-Oriented Research Career Development Award, Dr. Jackson will have acquired the necessary advanced PK and clinical trial skills to pursue a lifelong career in developing safe and effective drugs for critically ill infants. Further, he will establish a platform to systematically evaluate therapies for critically ill infants in the setting of procedures or disease states which are likely to alter drug PK, thereby advancing drug development in this vulnerable population.

NIH Research Projects · FY 2025 · 2023-08

Project Summary Patients with Alzheimer’s disease (AD) exhibit progressive memory loss, depression, and anxiety, accompanied by impaired adult hippocampal neurogenesis (AHN). Although young adult-born neurons (ABNs) have been shown to play an important role in memory and emotion processing under physiological conditions, their function and therapeutic potential in degenerated AD brains remain largely undefined. A long-standing question has been centering on whether AHN could be enhanced in otherwise impaired AD brains to restore cognitive and affective functions. Our recent study showed that stimulating hypothalamic supramammillary nucleus (SuM) exerts robust neurogenic effects in healthy wild-type (WT) mice. Specifically, chronic patterned optogenetic stimulation of SuM leads to increased production of behaviorally-relevant ABNs with enhanced developmental properties. Importantly, acute chemogenetic activation of these SuM-enhanced ABNs improves memory performance and reduces anxiety-like behavior. We further tested this strategy in 5xFAD mice. Strikingly, patterned SuM stimulation restores the number and developmental properties of ABNs and acute chemogenetic activation of a small population of these SuM-enhanced ABNs (~500 ABNs/DG, <0.05% total granule cells/DG) is sufficient to restore memory and reduce anxiety/depression-like behaviors in AD mice. These findings highlight the therapeutic potential of enhanced ABNs (number, quality, and activity) in functional restoration in AD. Building upon these findings, we propose the following aims to decipher the mechanisms underlying these beneficial effects mediated by activation of SuM-enhanced ABNs using two complementary AD mouse models. Aim 1 will determine the functional properties of SuM-enhanced ABNs and the molecular regulators underlying SuM- mediated enhancement of neurogenesis in AD mice. Aim 2 will determine activity-dependent contribution of SuM-enhanced ABNs to local hippocampal circuit and brain-wide network dynamics in AD mice. Aim 3 will determine the effects of SuM-enhanced ABN activation on microglia properties, AD pathology, and hippocampal function in AD mice.

NIH Research Projects · FY 2025 · 2023-08

Abstract HIV infection of the nervous system results in chronic infection, inflammation, neuropsychiatric problems and cognitive decline in up to 50% of people living with HIV with no effective treatments to-date. Inflammation appears early in the disease process and causes progressive neuronal damage due, in part, to factors released by activated microglia and macrophages. In cultured neurons and mice, expressing the HIV gp120 transgene these factors induce intracellular calcium accumulation, cytoskeletal damage and focal swelling, in a fashion similar to early Alzheimer’s disease (AD) pathology, suggesting a common substrate for disease progression. Age-dependent accumulation of the p75 neurotrophin receptor occurs early in disease and is thought to contribute to pathogenesis by shifting the balance of neurotrophin signaling away from protective, regenerative pathways. Treatment of aging and gp120 transgenic mice with a small non-peptide p75NTR ligand, LM11A-31, suppressed cholinergic degeneration, inflammation and neuronal damage. In cats chronically infected with feline immunodeficiency virus, ten weeks of oral treatment with LM11A-31 prevented degeneration, improved cognitive behaviors, reduced anxiety and CSF viral titers in the absence of any adverse effects on systemic viremia, PBMC FIV burden, or CD4:CD8 T cell ratios. Since p75NTR is normally expressed at very low levels in adult brain but is upregulated in response to injury or disease, it provides a unique target for therapy with minimal potential for off-target effects. The drug is orally bioavailable, crosses the blood brain barrier and has no significant adverse effects in humans at therapeutic concentrations. To explore the potential of LM11A-31 as a disease modifying neuroprotective treatment, the proposed studies will establish the safety and tolerability of LM11A-31 treatment in a small cohort of stable virally-suppressed participants with HIV and mild neurocognitive impairment. Safety measures will be supplemented with exploratory characterization of traditional and novel biomarkers for early detection of inflammation and neurodegeneration in CSF and blood. A novel fMRI Hcorr analysis will be used to provide a sensitive measure of early immune and p75NTR activation with the potential to identify individuals in early stages of neurodegeneration. Serial neuropsychological test results will provide preliminary data and facilitate transition to a subsequent efficacy trial for prevention of cognitive decline. These studies are expected to show that LM11A-31 is safe to use in people living with HIV and to lay the groundwork for a larger efficacy trial designed to demonstration protection from neuronal damage and cognitive decline.

NIH Research Projects · FY 2024 · 2023-08

PROJECT SUMMARY Significance: The child protection system (CPS) serves as a primary responder to prenatal substance exposure (PSE), although policies guiding CPS involvement following a substance affected birth vary across and within jurisdictional settings. While CPS plays an important role in protecting children from harm, nonuniversal reporting policies offer the potential to deploy CPS intervention more strategically. It is not well understood how PSE reporting policies are implemented by mandated reporters and how timing of CPS involvement for substance-exposed infants affects custodial outcomes. Moreover, mandated reporters can offer key insights into best practice policies and standardized tools that may improve the effectiveness of reporting policies at discerning when CPS intervention is needed to mitigate risk of child maltreatment. Specific Aims: The objective of this proposal is to elucidate the implementation and outcomes of CPS reporting policies and to enumerate promising practices for improving policy performance with three specific aims: (1) describe women diagnosed with substance use at delivery and those reported to CPS using descriptive statistics and multilevel modeling through an intersectional equity lens; (2) analyze 3-year custodial outcomes, comparing births with documented PSE that were and were not reported to CPS in the early neonatal period; and (3) through content analysis and semi-structured interviews, evaluate policy consistency and identify best practices that may attenuate family risk and reliance on CPS for certain families. Approach: For the first two aims, a nonpublic birth cohort dataset of linked administrative records from California will be used to conduct multilevel and multinomial logistic regressions. For the third aim, a content analysis of CPS reporting policies at 14 high-risk birth hospitals in Los Angeles County will be augmented by semi-structured interviews with labor and delivery providers at those institutions. The proposed project is innovative in its use of linked administrative data with a sufficient sample size for interrogative analyses of differential outcomes by demographic characteristics at individual and institutional levels. The project is also innovative in its inclusion of policy content analysis, which fills a key gap in the current policy outcomes literature. The project is significant in its contribution of individual-level longitudinal and in-depth qualitative information to a focus area with immediate policy and programmatic relevance. Fellowship Applicant: The training plan outlined in this proposal will equip the applicant, Julia Reddy, with advanced epidemiologic skills and critical policy and systems knowledge. This plan will prepare the applicant to successfully complete the proposed project and advance as an independent public health researcher, focusing on policies and programs to alleviate the burden of substance use on families. The applicant is well supported by a strong team of mentors and research advisors who have the requisite experience and training to guide her doctoral research and aid in her professional development, along with significant institutional support.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY/ABSTRACT Persistent hyperactivation of the Ras-Raf-MEK-ERK pathway contributes to oncogenesis in over 30% of human cancers. Trametinib (Trm) is a highly selective inhibitor of MEK1, the sole upstream activator of multifunctional pro-survival kinases ERK1/2. Trm commonly is used in combination with dabrafenib to prolong life in patients with melanoma; its efficacy in other common tumor types including triple negative breast cancer (TNBC) is being widely explored. Trm generally is well tolerated, though it can cause cardiomyopathy that may lead to heart failure (HF) in up to 11% of cases. The mechanisms underlying Trm-associated cardiotoxicity are unclear. Our preliminary data show that 14-day Trm treatment abrogated mouse myocardial ERK1/2 activation and induced reversible cardiac contractile dysfunction characterized by reduced mitochondrial abundance and compromised oxidative phosphorylation in vivo. RNAseq analysis of Trm-treated mouse hearts revealed broad decreases in mitochondrial transcripts and increases in immune response pathways that are molecularly distinct from other HF etiologies. In vitro exposure of primary cardiomyocytes to Trm caused mitochondrial injury and activated canonical inflammatory pathways. These surprising effects were not predicted by our current understanding of MEK-ERK cardiomyocyte biology or by our understanding of the anticancer mechanisms of MEK inhibitors (MEKi’s). Here we will use 3 specific aims to test the central hypothesis that MEK-ERK inhibition impairs OXPHOS to induce mitochondrial injury resulting in innate immune activation, and that these effects collectively contribute to both the cardiotoxicity and anticancer efficacy of Trm. In the mechanistic Aim 1 we will find if Trm induces mitochondrial injury by compromising oxidative phosphorylation and inducing oxidative stress. Aim 2 will determine whether genetic or pharmacological loss of MEK function is sufficient to induce cardiomyocyte mitochondrial injury using novel mouse models of cardiomyocyte MEK1 deficiency and other FDA-approved pharmacological MEKi’s. Aim 3 will test whether Trm-induced mitochondrial toxicity activates innate immune responses in cardiomyocytes and cancer cells using a validated mouse model of TNBC and a clinically relevant combination targeted therapy. These studies will establish whether activation of pattern recognition receptors by mitochondrial damage associated molecular patterns contributes to Trm cardiotoxicity or anticancer efficacy, and will define whether the addition of Trm to an immune checkpoint inhibitor enhances cardiotoxic risk. The proposed experiments have the potential to impact the fields of myocardial biology and cancer therapeutics in related but distinct ways: (1) Expand our understanding of MEK-ERK regulation of cardiomyocyte mitochondrial function; (2) Identify the molecular processes that contribute to Trm cardiotoxicity; (3) Determine whether mitochondrial toxicity and innate immune activation contribute to the anticancer efficacy of Trm and other MEKi’s.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY This mentored career development proposal will 1) generate a novel multimodal arousal-based objective biomarker of cognitive, social, and sensory outcomes in infants with DS and 2) establish Dr. Rebecca Grzadzinski as an independent clinical researcher in behavioral and neurobiological characteristics of infants with DS. The overarching hypothesis is that atypical arousal patterns in early life influence how an infant with DS interacts with, samples from, and learns within a multisensory environment. Building upon neurobiological findings in typical and neurodevelopmental disorders, we hypothesize that 1) social arousal is associated with parent- reported social skills as well as amygdala volume, 2) non-social arousal is associated with parent-reported sensory reactivity and occipital volumes, and 3) habituation to stimuli is associated with estimates of cognitive ability and frontal lobe volumes. By identifying these arousal patterns in real-time in response to specific, well- controlled stimuli, we can begin to develop novel early interventions that are tailored to the infant's unique arousal profile. Linking arousal dynamics with underlying neurobiology not only validates the constructs but also provides targets for dissection in preclinical models of DS. This proposal is an unprecedented and time-sensitive opportunity to capitalize on the largest longitudinally followed sample of infants with DS with robust behavioral and neurobiological phenotyping. The foundation of this work leverages the ongoing data collection pipeline of infants with DS from 6 to 24 months of age within the multi-site, longitudinal Infant Brain Imaging Study (IBIS; PI: Piven; R01MH118362; PI: Botteron; R01HD088125-01A1). With the support of this proposal, stimuli designed to elicit arousal-based responses will be added to the standard IBIS battery. Parent report and direct assessment measures will be extracted from the IBIS database and arousal biometrics will be linked with concurrent and longitudinal metrics of cognitive, social, and sensory behaviors in infants with DS. Dr. Grzadzinski has assembled an expert mentorship team, including Drs. Piven (Director of IBIS) and Hazlett (UNC Site PI), who will mentor her during completion of this project and ensure she has access to all the IBIS resources necessary to bring this project to fruition. Drs. Lynch, Rodriguez-Romaguera, and Vora complete her mentorship team by adding methodological, translational, and clinical expertise needed to guide Dr. Grzadzinski toward independence. This project is a groundbreaking opportunity to validate early arousal biomarkers of cognitive, social, and sensory outcomes in infants with DS and ultimately guide early intervention and preclinical research in DS. This proposal aligns with the NIH INCLUDE Project Research Plan to collect deep phenotyping data on individuals with DS by linking with existing cohorts and will position Dr. Grzadzinski to be a highly successful independent clinical researcher dedicated to improving the lives of individuals with DS and their families.

NIH Research Projects · FY 2024 · 2023-08

During HIV infection, a reservoir of latently infected cells forms that persists during therapy, and this reservoir represents the major barrier to an HIV cure. We and others have shown that HIV latency is an epigenetic phenomenon, characterized by distinct changes to chromatin structure and histone modifications that repress HIV gene expression, that can be transmitted through cell division. This heritable property of latency allows the latent phenotype to survive ongoing clonal expansion of infected cells in hosts and sustain the overall reservoir. Furthermore, viral silencing and epigenetic programming is linked to global changes that occur within CD4 T cells as they transition from an activated to a resting state. Fully defining the process by which the reservoir is formed and by which latency is programmed will be essential to guiding novel approaches to prevent reservoir seeding or maintenance. To date, studying the process of reservoir formation during clinical HIV infection has been considered difficult, if not impossible, due to prior observations suggesting that the reservoir forms very early during acute infection. Newer information from several groups, however, has now revealed that the majority of the reservoir is seeded by viruses that are actively replicating at the time of ART initiation, suggesting that ART initiation triggers seeding of the reservoir. This observation raises the exciting possibility that we could potentially study the process of reservoir seeding by longitudinal observation of CD4 T cells from PWH in the immediately post ART period and, by doing so, reveal potential ways to block the reservoir from forming at the time of therapy initiation. In this proposal we aim to comprehensively define epigenetic and chromatin-based changes that occur in CD4 T cells in the post ART period using samples derived from the A5248 cohort. CD4 T cells from these samples will be profiled using a series of cutting-edge assays that have been established and validated in our laboratory. These assays include combined single-cell multi-omic (RNAseq/ATACseq) analysis, and high-resolution genome-wide mapping of multiple key histone modifications through Cleavage Under Targets and Release using Nuclease (CUT&RUN). From this approach we will achieve an integrated understanding of how heritable patterns of chromatin-based changes in CD4 T cells are triggered by ART initiation and generate novel and critical insights into the intracellular conditions that coincide with reservoir seeding in vivo. By achieving this goal, we will reveal mechanisms that promote reservoir seeding and suggest novel approaches to block reservoir formation at the time of ART initiation.

NIH Research Projects · FY 2024 · 2023-08

Abstract Alzheimer’s Disease (AD) affects over 26 million people worldwide, yet the treatment options are limited. This is in large part due to the unclear molecular mechanisms underlying AD. Genome-wide association studies (GWAS) have identified genomic regions that are associated with AD, but determining the exact causal variants and genes remains a major challenge. Recent developments in high throughput genomic technologies have incredible potential to functionally characterize these causal features, but must be applied to the correct cell types. Neurons, astrocytes, and microglia are all thought to play key roles in the etiology of AD but obtaining viable primary human brain cells for these experiments is understandably very difficult. Therefore, recent protocols to rapidly differentiate human induced pluripotent stem cells into various brain cell types offer great promise as tools to decipher the genetic basis of AD and guide future therapeutic efforts. The goal of this project is to identify which AD risk variants alter transcriptional regulatory capacity in human brain cells and to map them to the genes they regulate. To understand which variants are functional in microglia, astrocytes, and neurons, I will perform massively parallel reporter assays in human induced pluripotent stem cells (hiPSCs) differentiated into each cell type (Aim 1). To identify AD risk genes, I will use publicly available Hi-C, ATAC-seq, and RNA-seq in hiPSC-derived microglia, astrocytes, and neurons to link variants to genes (Aim 2A). I will functionally validate a selection of putative variant-gene pairs with CRISPR inhibition (Aim 2B). The results of this work will identify cell-type specific causal variants, and the genes that they regulate. This will have a positive impact because understanding exactly which genes are involved in which cell types in AD will elucidate the molecular mechanisms of the disease etiology. The genes identified in this study can act as targets for future studies and candidates for therapeutic design.

NIH Research Projects · FY 2024 · 2023-08

Project Summary Single-cell immune profiling technologies, such as cytometry by time of flight (CyTOF) enable broad and comprehensive characterization of diverse immune cell-types. Moreover, such technologies are being increasingly applied in clinical settings to gain a holistic view of the immune system. Ex vivo stimulation is a common perturbation applied to immune cells and assayed through CyTOF, which elicits functional responses that may be clinically predictive. Such experiments generate single-cell measurements for a large number of cells, causing manual analysis to become time-consuming and biased towards studying immune cell-types and their functional responses that have already been well-characterized. Existing bioinformatics approaches for automating manual analysis are limited in that they 1) primarily focus only on partitioning cells into cohesive cell-populations, 2) need to be run independently per stimulation and 3) produce several immunological features encoding cell-type specific functional responses to stimulation that are not indicative of canonical immune signaling pathways. In this proposal, we introduce a fully automated approach for automating the analysis of multi-sample, multi-stimulation immune profiling data. In particular, we shall develop algorithms to efficiently identify clinically-predictive functional responses to stimulation in a scalable manner to enable analysis of large clinical cohorts under several stimulation conditions. Uncovered functional responses that are clinically predictive can be used to develop diagnostic tests or to design vaccines to elicit particular cellular responses.

NIH Research Projects · FY 2026 · 2023-08

Importance: Despite the emergence of virtual care (VC) programs during the COVID-19 pandemic, the sustainability of these programs is unknown because of concerns relating to health access in rural regions, effective integration into clinical workflows, future payment parity, and the misalignment of many of the goals of VC integration with a fee-for-service payment environment. Lack of access to Real-World VC Data and knowledge of the unique needs of different VC stakeholder groups can impede attaining financial sustainability. Similarly, there is no consensus on evidence-based research measurements specific to VC, which hinders the efficiency and sustainability of VC. Objective: Lay strong foundation for translation research that accelerates the integration and evaluation of VC. Specific aims: (1) Build and promote a productive coalition of internal and external resources, thought leaders, and stakeholder representatives to enable the use of Real-World virtual care Data and generate innovative and pragmatic approaches to advance scalable integration and value locally and nationally. (2) Assess the facilitators and barriers for key stakeholders to achieve scalable and sustainable virtual care by conducting semi-structured interviews. (3) Develop and validate consensus around VC Integration and Value frameworks (e.g., outcome metrics) that will accelerate future translational research and provide evidence-based guidance for VC service and policy. (4) Train workforce to implement validated VC Integration and Value frameworks to improve human health. Center Activities: ViVE will continuously grow by learning from conducting its research and supporting the research of others regionally and nationally. To the extent, ViVE will create new infrastructure and provide access to Real-World VC Research Data and VC Expertise that will support and advance VC research. ViVE will assess the facilitators and barriers to achieving cost-effective, impactful, and sustainable VC from key stakeholders using semi-structured interviews. Additionally, ViVE will shift the current status quo of VC research by building consensus around VC Integration and Value frameworks. To ensure the effective implementation of these frameworks, ViVE will conduct workforce training sessions to improve the knowledge and skills required to implement VC frameworks. Expected outcomes: On successful completion of our research, we expect contributions to include (1) accelerating clinical and translational science NC TraCS (UNC CTSA) by expediting the development of a VC research hub, (2) developing a national VC coalition that advances translational VC research by enabling researchers to access Real-World VC Data, resources, and expertise, (3) building and validating VC measurement approaches and value-based outcomes metrics for Integration and Value, and (4) demonstrating real-world utility of validated outcomes and measurements through implementation in clinical research studies.

NIH Research Projects · FY 2025 · 2023-08

Colorectal cancer (CRC) screening is one of the most effective tools to reduce cancer morbidity and mortality. Yet, CRC screening rates at federally qualified health centers (FQHCs) in rural areas lag behind more well-resourced healthcare systems and national goals. Improving CRC screening in rural FQHCs requires attention to the needs of their patient populations as well as their limited resources for implementation; yet, little research has tested CRC screening programs with FQHCs that use effective messaging for the patient population and alleviate implementation burden. Our long-term goal is to scale implementation of CRC screening solutions that will reduce burden on FQHCs. Our team has developed a novel digital health platform, mPATH-Cloud, that has the potential to help alleviate implementation burden on clinical teams by automating many key processes, all the while delivering CRC screening communication, education, and services in ways that have proven to be patient-centered and effective. Thus, our study seeks to evaluate mPATH-Cloud with rural FQHCs to demonstrate effectiveness at improving guideline concordant screening and identify critical implementation processes and outcomes that will impact future dissemination and scalability. We will use an embedded experimental mixed methods model, which includes an individual randomized trial of the multi-component intervention, quantitative and qualitative measures to identify ways to improve tailored messaging and adapt strategies to improve effectiveness across patient profiles, and quantitative and qualitative measures of processes and outcomes to improve implementation. Our team is well-situated to lead this research, which if successful, will lead to progress toward improving screening in low-income rural communities served by FQHCs.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY/ABSTRACT The health of persons with HIV (PWH) has improved with the expanded use of effective antiretroviral therapy. Despite these improvements, the risk of atherosclerotic cardiovascular disease (ASCVD) for PWH remains up to twice as high as for those without HIV. PWH bear a high burden of ASCVD risk factors such dyslipidemia and diabetes mellitus, which is increasing as PWH live longer. Statins have proven efficacy to prevent ASCVD. PWH have a greater statin need but lower rates of adequate response to statins than those without HIV, in large part due to nonadherence. There is a need for patient-centered interventions for improving statin adherence that adequately incorporate PWH-specific barriers, such as HIV stigma, low ASCVD risk perception, HIV treatment vs. ASCVD prevention prioritization, and pill fatigue and drug interaction fears from antiretroviral therapy. The objective of this K01 grant is to adapt an intervention promoting statin adherence from the general population to PWH and evaluate the adapted intervention’s acceptability and feasibility in an HIV clinic. We hypothesize that STIC2IT (Study of a Tele-pharmacy Intervention for Chronic diseases to Improve Treatment adherence, “Stick to it”) can be adapted to PWH. STIC2IT is a pharmacist-delivered intervention proven in the general population to improve chronic medication adherence including to statins, via motivational interviewing and tailored resources to reduce adherence barriers. We will analyze existing data from the Centers for AIDS Research Network of Integrated Clinical Systems (CNICS) and conduct in-depth interviews of PWH in the University of North Carolina Center for AIDS Research HIV Clinical Cohort (UCHCC). We will use interview findings to adapt the intervention and pilot it in the UCHCC. This career development award will provide the PI with training in: 1) qualitative research methods; 2) intervention adaptation and evaluation; and 3) ASCVD prevention and epidemiology. The PI will be closely guided by an interdisciplinary mentoring team of experts in health behavior, epidemiology, cardiology, HIV care, and intervention trials. The Specific Aims are: 1) Among PWH, identify contemporary longitudinal patterns of statin use and effectiveness, and patient groups at greater risk of suboptimal statin use; 2) Systematically adapt the STIC2IT intervention to the needs and preferences of PWH; and 3) Evaluate the acceptability and feasibility of the adapted intervention in an HIV clinic. Carrying out these research aims will reinforce training activities and leverage the PI’s existing skills in HIV, clinical epidemiology, and pharmacoepidemiology studies using large, electronic health records-based clinical cohorts. The study will produce preliminary data for future study planning and a prototype adapted intervention ready to be evaluated for efficacy in R-level grants. This award will support the PI’s career goal of becoming an independent investigator at the forefront of innovative research to improve ASCVD prevention for PWH.

NIH Research Projects · FY 2025 · 2023-08

Project Summary Natural products serve crucial roles in the pharmaceutical industry as drugs or leads for drug compounds. Generated through secondary metabolism, these molecules impact the virulence, symbiosis, and survival of microorganisms. The nonproteinogenic oxyvinylglycine amino acids are an interesting class of secondary metabolites characterized by the presence of a vinyl oxygen moiety. Members of this class, such as 4-(2’- aminoethoxy)vinylglycine (AVG), are known to arrest germination in plants by inhibiting the pyridoxal 5’- phosphate (PLP)-dependent enzyme 1-aminocyclopropane-1-carboxylate (ACC) synthase.2 While the biosynthesis of vinyl ether-bearing oxyvinylglycine nonproteinogenic amino acids including AVG has been explored, the formation of other members of the family with alternative functional groups remains undetermined. 4-Formylaminooxyvinylglycine (FVG), an oxyvinylglycine containing an N–O bond, was reported to have duel herbicidal and bactericidal activity.3,4 The gvg biosynthetic gene cluster in Pseudomonas fluorescens strain WH6 is responsible for the biosynthesis of FVG and the related compounds guanidinooxyvinylglycine (GOVG) and aminooxyvinylglycine (AOVG) though the exact biosynthetic mechanism remains unclear.5,6 In this proposal I will determine the biosynthetic pathways responsible for the formation of FVG, GOVG, and AOVG. I will use a combination of feeding experiments and in vitro biochemical assays to determine the substrate and product of each enzyme along the biosynthetic pathway of these three nonproteinogenic amino acids. The vinyl alkoxyamine is unusual in amino acids, therefore I will characterize the enzyme responsible for N–O bond construction and determine its chemical mechanism. These studies will facilitate the bioinformatic discovery of similar oxyvinylglycine nonproteinogenic amino acids. Moreover, characterization of the iron-dependent enzyme responsible for N–O bond formation will facilitate its use in a synthetic context to expand the repertoire of oxidative biocatalysts.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY βII-spectrin (encoded by SPTBN1), is a ubiquitous component of the submembrane neuronal cytoskeleton. βII- spectrin binds F-actin and ankyrins to organize complex networks of ion channels, membrane transporters and cell adhesion molecules. βII-spectrin also promotes bidirectional transport of organelles and vesicles. Our lab recently reported de novo SPTBN1 variants as the genetic cause of a developmental delay syndrome that is comorbid with intellectual disability, autism spectrum disorder, ADHD, and seizures. However, the neuron types and brain circuits most vulnerable to deficits in βII-spectrin function and their specific contribution to the diverse neurological presentations are not fully elucidated. My preliminary studies indicate that βII-spectrin plays important roles in modulating cerebellar function and that cerebellar dysfunction may contribute to the SPTBN1 syndrome. To begin to unravel the roles of βII-spectrin in the cerebellum, I will focus on investigating its function in cerebellar granule cells by determining how βII-spectrin promotes: 1) the organization of excitable axonal domains and 2) axonal organelle dynamics.

NIH Research Projects · FY 2024 · 2023-08

PROJECT SUMMARY Transgender (TG) individuals have high prevalence of depression (64%) and are nearly nine times as likely to attempt suicide compared to the general population. Studies have not consistently collected data related to TG identity nor have they used the recommended two-step method of asking for assigned sex at birth and current gender identity. This population is largely overlooked in epidemiologic studies due to small sample size. With inconsistent and inaccurate ascertainment of TG patients in real-world data sources, TG people are missed and their health trends over time are understudied. Researchers are unable to identify and meaningfully address mental health inequities for this population, which can further exacerbate and perpetuate psychiatric conditions. It remains unclear what the health care utilization trends are for TG patients with psychiatric disorders and their adherence and persistence to psychiatric medications over time. Understanding this population’s mental health using large datasets is imperative in order to optimize the care management of psychiatric conditions experienced by TG people. The objectives of this proposal are to: (1) apply and evaluate the performance of existing computational phenotypes (CPs) to identify TG patients with depressive disorders (DD), anxiety, and attention deficit disorders (ADD), (2) assess adherence and prevalence of psychiatric medications among TG patients diagnosed with psychiatric disorders compared to cisgender patients with these diagnoses, and (3) examine the risk of non-fatal self-harm among TG patients with psychiatric disorders receiving psychotherapy compared to TG patients not receiving psychotherapy. For all aims, IBM MarketScan from years 2008 to 2020 will be used, which is a large, longitudinal medical claims database that includes inpatient and outpatient visits and prescription medication use. The completion of the proposed aims will provide real-world evidence on mental health care for TG individuals in the United States. The training plan outlined in this proposal will equip the applicant with critical knowledge and necessary skills in social and pharmacoepidemiology and transgender mental health. This plan will prepare him to successfully complete the proposed aims and to progress into a role as an independent, interdisciplinary researcher studying the intersection of pharmacoepidemiology and transgender health equity in the US. The applicant is extremely well supported by an interdisciplinary group of social, psychiatric, and pharmacoepidemiology faculty, health disparities researchers, and pharmaceutical researchers with the requisite expertise to support his doctoral research and prepare him for the next phase of his career.

NIH Research Projects · FY 2025 · 2023-08

ABSTRACT Melanoma is the deadliest form of skin cancer. The FDA-approved immune checkpoint inhibitors targeting PD1 and CTLA4 and the targeted therapies against BRAF and MEK have greatly improved overall survival in metastatic melanoma. Nevertheless, many patients die from metastatic melanoma including those with inflamed tumors (i.e., tumors bearing tumor-infiltrating lymphocytes). There is therefore room to improve melanoma treatments for human patients. Here we propose the development of therapeutic mRNA vaccines against melanomas. Specifically, our proposal leverages a materials optimization approach to identify an Optimized Tannic Acid Lipid Nanoparticle Formulation that can suppress melanoma growth by delivering mRNAs encoding Melanoma-Associated Antigens into Dendritic Cell Populations. In undertaking this approach, this proposal aims to further our understanding of the mRNA delivery capabilities of Tannic Acid Lipid Nanoparticles while simultaneously laying the groundwork to advance therapeutic mRNA vaccines against melanomas toward the clinic.

NIH Research Projects · FY 2024 · 2023-08

PROJECT SUMMARY Kombucha is a popular fermented tea that contains probiotics. This beverage has seen a surge in popularity in the United States since the turn of the century and is purported to have many health benefits. Some of these health claims have been cursorily examined, however, none have been rigorously tested and the mechanistic interactions between the microbial components of Kombucha and the host remains unexplored. I will elucidate the host metabolic response to consumption of Kombucha-associated microbes (K. microbes), thereby informing its use in complementary health approaches. The impact of individual probiotic microbes on human health is difficult to deconvolute as humans consume a complex diet, have trillions of gut microbes (including many unidentified species), and measuring host-microbe interactions is not feasible in human subjects. Therefore, animal model systems are essential to investigate the effects of consuming probiotics, including those in Kombucha, on host physiological processes. Caenorhabditis elegans is an excellent model system to explore how K. microbes modulate the host pathways that govern lipid homeostasis, because their microbiomes are easily manipulated through the food source provided and they are a well-established system to study metabolism and the aging process in vivo. I have established a standardized method to maintain C. elegans on a diet exclusively consisting of K. microbes that is consistent with the community found in the fermenting culture (confirmed through 16S rRNA sequencing). In preliminary investigations, I observed that populations of C. elegans exclusively consuming K. microbes, as compared to a control diet (E. coli, the standard laboratory food source), have altered expression of core lipid metabolism genes (e.g., beta-oxidation, fatty acid desaturation), decreased fat levels, and an increased median lifespan. Critically, the molecular mechanisms by which K. microbes alter host physiology is completely unknown. Therefore, I plan to use molecular and genetic approaches in C. elegans to systematically identify the molecular mechanisms that govern the host response to K. microbe consumption and elucidate the components of Kombucha that are necessary and sufficient to confer the observed metabolic and lifespan phenotypes. The proposed experiments will provide unprecedented insight into the mechanism by which K. microbe consumption reconfigures host metabolism.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY Gradient-recalled echo (GRE)–based echo planar imaging (EPI) has been the gold standard functional magnetic resonance imaging (fMRI) technique for nearly three decades due to its ability to rapidly acquire whole brain volumes with MR T2* sensitivity to blood oxygenation — a well-known surrogate marker for brain activity. This immensely utilized technique, however, suffers from high acoustic noise, ghosting and motion artifacts, magnetic field inhomogeneity–related artifacts, low sensitivity compared to other neuroimaging modalities, and poor spatial specificity. An fMRI sampling technique that addresses these problems has the potential to change day-to-day fMRI practices. In particular, such a development would be of great benefit to the emerging rodent fMRI community as anesthesia and stress confounds can be avoided. Additionally, most rodent fMRI studies are performed under high magnetic field strengths (> 7T), wherein susceptibility artifacts in GRE-EPI are exacerbated. Imaging sequences with “zero” acquisition delay and minimal increment of gradients are insensitive to problems stated above and have the potential to provide superior specificity and sensitivity compared to GRE- EPI-fMRI. The overarching goal of this project is to advance, validate, and disseminate a novel 3D brain- wide imaging sequence: Steady-state On-the-Ramp Detection of INduction-decay signal with Oversampling (SORDINO) for the preclinical animal fMRI community. In addition, we will investigate SORDINO contrast mechanisms and explore a contrast-enhanced method that may further augment SORDINO sensitivity. Our developments will be benchmarked in mice, wherein a head-fixation approach can be utilized to image mice in an awake condition. In Aim 1, we will develop and disseminate the SORDINO sequence and reconstruction package in a preclinical animal MRI platform. In Aim 2, we will inform the most robust imaging parameters and benchmark them against modeled SORDINO performance and GRE-EPI-fMRI and zero echo time (ZTE)-fMRI data. This will facilitate future SORDINO-fMRI applications and enable new capabilities to study large-scale, functionally and behaviorally relevant brain networks in awake mice. In Aim 3, we will examine the SORDINO contrast mechanisms using MR-compatible invasive recordings, which are crucial for data interpretation. The contrast mechanisms, if proven to be local tissue oxygenation, cerebral blood flow, and cerebral blood volume, will clarify SORDINO as a spatially specific approach for functional brain mapping. In Aim 4, we will leverage the expected sensitivity gain of SORDINO at shorter baseline T1 values and use a simple manganese-enhanced MRI (MEMRI) strategy, a method widely utilized by many preclinical MRI labs, to further augment awake mouse SORDINO-fMRI sensitivity. Overall, we expect the knowledge and deliverables in this work to have widespread implications and will significantly advance fMRI technologies. We also expect this work to have extended impacts on studies requiring rapid mapping of T1 changes such as dynamic-contrast-enhanced MRI and molecular MRI.

NIH Research Projects · FY 2025 · 2023-08

Project Summary/Abstract Bladder cancer is a prevalent and deadly cancer, with over 80,000 new cases and 17,000 deaths annually in the United States. Advanced bladder cancer has only a 15% 5-year survival rate. One of the most effective treatments for advanced bladder cancer is immune checkpoint blockade (ICB), but only 20-30% of patients with advanced bladder cancer respond and most responses are not enduring. A promising new treatment identified by our group to improve bladder cancer ICB response is the selective class 1 histone deacetylase inhibitor entinostat. In a mouse model, entinostat plus anti-PD-1 (αPD-1) ICB induced complete, enduring responses in 67% of mice. Entinostat decreased intratumoral M-MDSC and Treg populations, decreased tumor single- nucleotide variant (SNV) neoantigen burden in vivo, increased expression of some SNV neoantigens in vitro, and increased T cell specificity for these neoantigens in vivo. However, much of the mechanism behind response to entinostat plus αPD-1 is unknown, particularly how entinostat decreases immunosuppressive populations and affects expression of the neoantigen landscape. Understanding this mechanism is important to predict which patients will respond and to potentially improve responses through antigen-directed therapy. We hypothesize that entinostat-induced ICB response is driven by increased M-MDSC differentiation, decreased M-MDSC migration, and increased expression of suppressed immunogenic neoantigens, augmenting response to neoantigen vaccination. I will investigate two components driving response to entinostat plus αPD-1: M-MDSCs and neoantigens. The training in computational and wet lab immunology, tumor biology and genetics, orthotopic murine tumor models, and translational research with a clinical trial, will assist me in becoming an independently funded physician-scientist leading a cancer immunology research lab and caring for bladder cancer patients. In our M-MDSC-focused Aim 1, I will perform flow cytometry and transwell migration assays with M-MDSCs from orthotopic bladder cancer model tumors to assess whether M-MDSC differentiation and migration are affected by entinostat treatment. I will conduct immunofluorescence staining of human tumors from the LCCC1827 entinostat window trial (NCT03978624) to assess whether adding entinostat to ICB treatment decreases M- MDSCs in humans. The Vincent Lab has developed LENS, a software platform to identify neoantigens from multiple genomic sources. In our neoantigen expression-focused Aim 2, I will use LENS to identify all the neoantigens in 3 murine bladder cancer lines developed by the Kim Lab, test T cell neoantigen specificity by high-throughput ELISPOT, and use statistical modeling to predict neoantigens immunogenicity. I will also validate whether entinostat-induced immunoediting occurs in human tumors from LCCC1827. In our neoantigen vaccination-focused Aim 3, I will test whether neoantigen vaccination improves tumor response to entinostat plus αPD-1. I will treat orthotopic tumors, measure their growth, and perform flow cytometry and single cell RNAseq to measure non-exhausted neoantigen-specific CD8+ T cell abundance.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY/ABSTRACT This K08 Career Development Award details a 5-year training program to advance my career goal of becoming an R01-funded physician-scientist focused on elucidating thrombotic mechanisms in myeloproliferative neoplasms (MPN) in order to find new treatment targets and improve care of MPN patients. During the award period, I will continue developing expertise in mechanistic understanding of and models of thrombosis, acquire new scientific skills, advance translational capabilities, and generate publications and data that will serve as the foundation for a successful R01 application. Under the guidance of my primary mentor, Dr. Rafal Pawlinski, and co-mentors, Drs. Jonathan Serody and Alison Moliterno, these training objectives will be met by a combination of didactic course work, participation in seminar series, research experience, and mentoring by my advisory committee. Dr. Nigel Key and Dr. Josef Prchal will serve as advisors on the proposal. The scientific proposal is aimed at identifying thrombotic mechanisms in JAK2V617F-positive MPN. Thrombosis remains the leading cause of mortality in the major MPN subtypes polycythemia vera and essential thrombocythemia. Circulating blood cells are both increased in quantity and qualitatively abnormal in MPN. Current treatment paradigms aim to normalize the number of circulating blood cells to improve blood rheology. However, despite current therapies 25% of MPN patients will experience a thrombotic event after diagnosis. Understanding the basis of thrombosis and developing primary and secondary prevention strategies are key unmet needs in this field. Dr. Prchal and I recently reported that upregulation of hypoxia-inducible factor (HIF)- mediated gene expression in neutrophils of MPN patients associated with thrombosis history. Importantly, we also found increased neutrophil gene expression of tissue factor (TF), the primary initiator of the extrinsic pathway of coagulation. We extended this finding, demonstrating that MPN neutrophils possess TF procoagulant activity. Plasminogen activator inhibitor-1 (PAI-1) is the primary physiologic inhibitor of fibrinolysis; its gene expression was also increased in MPN patients. I therefore hypothesize that JAK2V617F-driven increases of HIF activity leads to upregulation of TF and PAI-1, thereby increasing the risk of MPN thrombosis. In Aim 1, I will use a mouse model of venous thrombosis (VT) to evaluate (1) the functional consequence of increasing JAK2V617F transgene copies to VT, (2) the effect of HIF-1α or HIF-2α inhibition to VT, (3) the contribution of JAK2V617F mutation in hematopoietic versus endothelial cells to VT, and (4) the effect of neutrophil TF to VT. In Aim 2, I will evaluate the effect of 0, 1, or 2 JAK2V617F-mutated alleles on heterogeneity of neutrophil gene expression in MPN patients using single cell RNA sequencing with overlayed single cell genotyping. The 2 Aims are complementary but independent and will identify new targets for the prevention of MPN thrombosis and set the stage for additional investigations.

NIH Research Projects · FY 2025 · 2023-08

Project Summary: Membrane protein (MP) biogenesis begins in the endoplasmic reticulum (ER) and is a complex process, as domains on both sides of the ER membrane, and within the membrane bilayer, must fold and assemble. MPs understudy include ABC-Transporters, P-Type ATPases, G-protein coupled receptors, and BRICHOS proteins. Missense mutations that cause misfolding and premature degradation of MPs give rise to diseases such as cystic fibrosis, hypogonadotropic hypogonadism, retinitis pigmentosa and idiopathic lung fibrosis. In order to prevent toxic accumulation, misfolded MPs are targeted for ER-associated degradation (ERAD) by E3 ubiquitin ligase complexes. The ER transmembrane Hsp40 DNAJB12 (JB12) recruits cytosolic Hsp70 to the cytoplasmic face of the ER and together these chaperones deliver the misfolded MPs to ERAD machinery. In order for a misfolded protein to be a candidate for ERAD however, it must be competent for extraction from the confines of the ER membrane and delivered to the cytosolic proteasome. Misfolded proteins with structural restraints that prevent entrance into the proteasome necessitate an alternative quality control mechanism to ensure degradation. Misfolded MPs expose surfaces in the ER lumen, membrane, and the cytosol, so the coordinated action of ERQC factors in different locations manage this challenge. Mistakes in MP protein management are fatal when rogue clients adopt a toxic shape that enable rogues to damage membranes and dominantly poison essential cell functions. Hsp70 and Hsp40s act with folding and degradation machines to triage MPs. They shield against proteotoxicity through suppressing aggregation, refolding clients, selection of clients for degradation and regulating flux though protein biosynthetic systems. A major problem to ERQC systems are the MPs that accumulate in thermodynamically stable intermediate states that are non-native and self-associate to form oligomers, amorphous aggregates, and amyloid-like fibrils. Such misfolded conformers bury surfaces that are normally recognized by ERQC factors, and their thermodynamic stability hinders the unfolding events required for their extraction from membranes and degradation in the narrow central cavity of the proteasome. Thermodynamically stable MP intermediates are resistant to ERAD and we discovered that they are degraded by a JB12 dependent ER-phagy mechanism. The overall goal of the experiments included in this proposal is to define nodes of cross-talk between the Hsp70 chaperone system, ERAD and ER-phagy that are essential for cell viability and proteome maintenance.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY/ABSTRACT Young adults with cancer need tailored behavioral interventions to improve their psychosocial health. Any cancer diagnosis in early adulthood can create debilitating life disruptions that increase social isolation that in turn can compromise psychosocial health. Social isolation also predicts mortality comparably to other well- established risk factors, including tobacco use, excessive alcohol consumption, obesity, and sedentary status. This conclusion—described as “unequivocal”—was established by a large-scale meta-analysis and now fuels the call for low-cost and scalable behavioral interventions optimized for vulnerable populations to increase social connectedness. The demand for such interventions is especially pressing for young adults with cancer, whose unique needs have long gone unmet. The broad, overarching objective of this work is to optimize an evidence-based social connectedness intervention for young adults with cancer and test whether it improves their psychosocial health. This intervention, delivered digitally and effective among young adults (noncancer samples), prompts individuals to increase the emotional quality of their in-person social encounters. Our multi- disciplinary team will carry out a rigorous, randomized controlled trial—the Keep Social RCT—using our simulated social media platform to deliver intervention messages optimized for young adults with cancer while collecting repeated measures of day-to-day experiences and psychosocial health outcomes. This program of research is designed to meet three specific aims. SPECIFIC AIM 1 is to optimize our social connectedness intervention for young adults with cancer. This aim will be met using a human-centered communication science approach to enhance the positive reception of health messages with social context cues (human imagery, peer stories), and conduct an online experiment with 400 young adults with cancer to identify the most effective intervention messages for use in the Keep Social RCT. SPECIFIC AIM 2 is to pilot, conduct, and analyze the Keep Social RCT to test whether our social connectedness intervention, delivered via social media, improves psychosocial health in young adults with cancer. After thorough pilot testing, this aim will be met by conducting our placebo controlled Keep Social RCT with repeated assessments over six weeks. These data will allow us to test whether our intervention raises social and emotional well-being (primary outcomes) and improves resilience and negative mental health symptoms (secondary outcomes). SPECIFIC AIM 3 is to extend data analyses of the AIM 2 Keep Social RCT to test theory-based mechanisms and explore moderators of intervention effectiveness to pave the way for further optimization. This aim will be met with statistical modeling to identify how and for whom our social connectedness intervention improves psychosocial health among young adults with cancer. Our multi-disciplinary team brings together expertise in social psychology, emotion science, communication science, and oncology to pursue these aims to produce translation-ready pragmatic knowledge to improve the quality of life among young adults with cancer in the United States.

NIH Research Projects · FY 2025 · 2023-07

PROJECT SUMMARY HIV prevention requires improvements in effectiveness, reduction of side-effects, and removing barriers to adherence for antiretroviral pre-exposure prophylaxis (PrEP). Evaluation of these improvements through randomized trials remains difficult due to sample size requirements, strict eligibility criteria, and assessments limited to active comparators. Addressing these challenges has made novel analytical approaches increasingly necessary. The proposed research will use cuttingedge quantitative methods to evaluate new PrEP combinations by combining diverse sources of information. Data from the HIV Prevention Trials Network 083 and iPrEx (Preexposure Prophylaxis Initiative) trials will be used to compare long-acting injectable cabotegravir PrEP to placebo among men who have sex with men. Results will provide a reliable estimate of the efficacy of long-acting injectable cabotegravir in lieu of direct randomized comparisons, which are not forthcoming. Next, data from the VOICE (Vaginal and Oral Interventions to Control the Epidemic) trial will be integrated with subject-matter expert knowledge through statistical and mechanistic modeling to evaluate the expected efficacy of tenofovir alafenamide and emtricitabine daily oral PrEP among women. Results from this second analysis can aid in the planning of randomized trials of tenofovir alafenamide in women (e.g., assess whether a planned trial would likely fail to demonstrate efficacy under previously observed adherence patterns). Finally, flexible analytic tools to apply the quantitative methods used in the proposed research will be developed and made freely available through open-source software. Provision of these tools will decrease barriers to future applications. Scientific results from this proposal will accelerate and strengthen how we can learn from randomized trials and make strides in the prevention of HIV. The candidate will benefit from strong mentorship and additional training in HIV epidemiology, mechanistic modeling, semiparametric theory, and guided development as an independent scientist. Through additional quantitative methods training, the candidate will be uniquely prepared to jointly use statistical and mechanistic modeling to bring field-specific strengths to address deficiencies that neither field can easily address on its own. Completion of the training and research aims of this mentored developmental award will situate the candidate at the forefront of HIV epidemiology and methodological research and prepare the candidate to become an independent researcher.

NIH Research Projects · FY 2026 · 2023-07

PROJECT SUMMARY/ABSTRACT Antimicrobial resistance (AMR) is a rapidly growing threat to global health that is primarily driven by the overuse and misuse of antimicrobials. The applicant’s preliminary work in Uganda confirmed what has been noted in other resource-limited settings - children who present with febrile illnesses, particularly those with associated respiratory symptoms, are frequently treated with antibiotic therapy despite most of them likely having self-limited viral infections that do not require such treatment. This inappropriate dispensation of antibiotics is in part due to the diagnostic uncertainty inherent in the reliance on clinical symptoms for diagnosis and management of acute respiratory infections (ARI). Therefore, there is an urgent need for novel diagnostic tools that can distinguish children with bacterial ARI from those with non-bacterial infections, thus reducing antibiotic overuse for children presenting with this clinical syndrome. The objective of the scientific aims proposed in this K23 application is to develop a diagnostic model that accurately predicts bacterial infection in children with febrile ARI in Uganda. This work will facilitate the long-term goal of the applicant, which is to become an independent investigator with expertise in diagnostic evaluation and implementation working to improve quality of care and antimicrobial stewardship in both domestic and global contexts. Specifically, under the mentorship of experts in the fields of emerging molecular technologies, diagnostic evaluation, and prediction modeling at the University of North Carolina at Chapel Hill, she will (1) determine the etiology of febrile ARI in a cohort of previously and prospectively enrolled children, enhancing the diagnostic assessment with PCR-based and metagenomic next generation sequencing tools, (2) validate a host immune response gene expression assay, incorporating genes previously identified to be differentially expressed in viral and bacterial ARI, that minimizes the number of genes included to maximize feasibility in resource-constrained settings, and (3) develop novel clinical algorithms that combine host-based classifiers with other clinical and laboratory data to accurately predict bacterial ARI. Through pursuit of the scientific aims, the associated experiential and hands-on laboratory and biostatistical training, and focused didactic coursework, the applicant will address the following gaps in her knowledge: (1) molecular technologies and their role in infectious disease diagnosis and diagnostic development, (2) clinical prediction modeling, and (3) diagnostic tool evaluation and implementation. By the conclusion of the K23 award period, the applicant will have generated key results to inform a competitive R01 application. She will also be well-positioned to transition into an independent physician scientist and leading expert in diagnostic evaluation and antimicrobial stewardship in resource- constrained settings.

NIH Research Projects · FY 2024 · 2023-07

Abstract Persistent quadriceps muscle dysfunction following anterior cruciate ligament (ACL) injury and reconstruction (ACLR) is a critical clinical concern impacting the success of postoperative rehabilitation and prognosis of long- term joint health. Our novel working hypothesis is that worse quadriceps muscle quality, caused by a progressive increase in non-contractile tissue within the muscle, post-ACL injury and ACLR is a critical and understudied mechanism underlying poor clinical outcomes. There is a significant scientific gap in our understanding of the mechanistic pathway linking changes in quadriceps muscle quality to poor clinical outcomes. Our preliminary work using ultrasonography to assess changes in muscle quality supports our working hypothesis, in that patients with an ACL injury demonstrate muscle tissue image signal changes consistent with increased non- contractile tissue makeup in the first 3 months post-ACLR. Furthermore, ultrasonographic muscle tissue signal changes are associated with lesser knee extensor strength and worse physical performance (i.e., hop testing). Unfortunately, rigorous studies to test our working hypothesis have not been conducted to comprehensively evaluate the effect of ACL injury on muscle quality and the impact of poorer muscle quality on clinical outcomes. Recent magnetic resonance imaging (MRI) innovations now allow for high-precision and rapid evaluation of muscle quality throughout the entire muscle volume and in individual quadricep heads. We can be opportunistic and leverage an ongoing rehabilitation-based parent clinical trial already collecting critical clinical outcomes of knee extensor strength, gait biomechanics, physical performance and patient-reported outcomes (PRO), and tibiofemoral cartilage composition at preoperative, and 1-, 6-, and 12-month post-ACLR timepoints. We are proposing to test our working hypothesis with an ancillary R21 by conducting the following specific aims: 1) determine longitudinal changes in quadriceps muscle quality following ACL injury and ACLR preoperatively and at 1-, 6- and 12-months post-ACLR; and 2) determine the associations between changes in muscle quality and a) knee extensor strength; b) gait biomechanics; c) PRO and physical performance; and d) tibiofemoral cartilage composition. Our study is innovative as: 1) we are testing a novel hypothesis that quadriceps muscle quality changes early post-ACL injury and that it is a critical mechanism associated with poor clinical outcomes; 2) we are utilizing a novel MRI technique capable of collecting highly-sensitive measures of muscle quality in individual heads of the quadriceps throughout the entire muscle volume; and 3) associations between muscle quality and a comprehensive host of clinical outcomes (i.e. knee extensor strength, gait biomechanics, physical performance and PRO, and tibiofemoral cartilage composition) can be evaluated as part of the ancillary R21. The proposed R21 is significant as identifying the association between deleterious changes in muscle quality and poor clinical outcomes is the first critical step in developing the next generation of interventions to address the underlying mechanistic muscular changes leading to poor outcomes following ACL injury and ACLR.