University Of Wisconsin-Madison

NIH Research Projects · FY 2025 · 2023-09

PROJECT ABSTRACT This project addresses a need for less morbid alternatives to surgical drilling of growth plates in the treatment of limb length discrepancies. Surgical approaches currently require 6 weeks of recovery before weight bearing, which takes a physical and psychological toll on pediatric patients. Surgery has also been associated with complications such as incomplete growth arrest, angular deformity, bleeding, and infection. We hypothesize that microwave ablation – a technology already used for treating malignant and benign tumors throughout the body, including in bones – can be used to disrupt the growth plate with fewer complications and faster return to baseline activity. Preliminary data demonstrates the feasibility delivering microwave energy to create heating in the growth plate when using clinical microwave tumor ablation systems in porcine tibias. This project will focus on developing more optimal devices and techniques for growth plate ablation. Directional antennas will be developed that target microwave energy to the growth plate while minimizing collateral damage. Dynamic positioning and multi-applicator techniques will be used to further refine energy delivery to ensure complete and uniform growth arrest. Finally, the safety and efficacy of the optimized techniques will be compared against the gold-standard of surgical drilling in distal femur, proximal tibia, and fibula. If successful, these developments and studies will form the basis for a novel and exciting treatment for limb length discrepancy in children.

NIH Research Projects · FY 2024 · 2023-09

PROJECT SUMMARY Genome-wide association studies (GWAS) have identified numerous genetic loci associated with almost all complex human diseases. Much of this success, particularly the accelerated findings in recent years, is credited to the development of deeply phenotyped population biobanks with matched genomic data. However, a crucial limitation of these population biobanks is the often-insufficient number of disease cases for late-life health outcomes, which is why the introduction of the concept of GWAS-by-proxy (GWAX) served as a landmark in the field. The GWAX study design is based on a simple idea – although biobank participants may not have their own diagnosis on late-life disease outcomes, they provide such diagnosis of their parents through the family health history survey; they also (indirectly) provide parental genetic data, as their biological child. Since this study, GWAX has been widely used in genetic studies for many diseases, but particularly frequently for neurodegenerative diseases. Every recent Alzheimer’s disease (AD) GWAS performed meta-analysis to combined case-control associations with GWAX proxy associations to boost sample size and statistical power. However, methodological issues in GWAX and the quality of its association results have not been carefully investigated. We demonstrate pervasive biases in current GWAX approaches, causing substantial divergence of GWAS and GWAX results. In addition, we demonstrate that education is an important social factor at the center of many of these biases. Since cognition is such a crucial marker for AD, biases caused by education/cognition become particularly important in AD genetics research and will give completely misleading results if not handled properly. Our proposal takes advantage of extensive family health history data available in the AllofUs research program and recent statistical advances developed by our investigator team in decomposing social genetic effects with summary statistics of multi-generational GWAS. We aim to expand these methods to rigorously and comprehensively characterize the biases in current GWAX results. Our central hypothesis is that GWAX associations based on family health history as proxy for disease phenotypes are substantially affected by survival bias and non-random over- and under-report of family member’s illness, and will lead to erroneous results and conclusions for analyses that naively combine these associations with case-control GWAS results. Successful completion of this proposal will improve scientific understanding of the genetic underpinnings of family health history, shed important light on the design and analysis of mid-aged biobank cohorts, and provide novel analytical strategies for future genetic studies leveraging family health history data in population biobanks.

NIH Research Projects · FY 2025 · 2023-09

Alcohol-associated liver disease (ALD) rates have risen markedly over the past 15 years, becoming the most common indication for liver transplantation in the U.S. and generating the majority of healthcare and cost burden among all liver diseases. With the COVID pandemic, these trends have worsened, and it is estimated that, if nothing is done to stem the tide, ALD-related mortality will double by 2040. Despite decades of medical research, alcohol cessation remains the only intervention that substantially decreases long-term ALD morbidity and mortality. However, only 10-15% of ALD patients access alcohol use treatment in the first year after their diagnosis, with women even less likely to access treatment compared to men. Despite these gaps, surprisingly few behavioral interventions for alcohol cessation have been tested in ALD patients, and, of those that have been tested, integrated alcohol cessation treatment alongside medical and hepatology care has had the most impact at reducing alcohol use. To address these critical research gaps, the investigators will perform a randomized, controlled, Type 1 hybrid implementation-effectiveness trial in a population of ALD patients to evaluate the effectiveness of CHESS Health Connections (a smartphone app for alcohol cessation shown to significantly reduce risky drinking in a prior randomized clinical trial of patients with severe alcohol use disorder). Patients will be enrolled in both general hepatology and multidisciplinary ALD clinics (which include integrated alcohol use treatment professionals alongside hepatology providers) at two large tertiary care centers (University of Wisconsin and University of Michigan). Aim 1 will compare the effectiveness of CHESS plus usual care (n=180) versus usual care (n=181) on days of abstinence over 6 months. Aim 2 will assess implementation of CHESS through qualitative interviews of key patient, provider, and clinic-level stakeholders using the Replicating Effective Programs framework and implementation costs. Our secondary/exploratory analyses will examine intervention effects on health outcomes including depression, anxiety, insomnia, AUD treatment engagement, and liver health. We will examine key moderators (age, sex, rurality, presence of formal AUD treatment, and stage of ALD) and mediators (relatedness, competence, autonomous motivation) on outcomes. We will also examine the impact of the CHESS app on measures of chronic liver impairment using the Model for End-Stage Liver Disease-Sodium score. This study will build on over a decade of work in adapting and using CHESS in various populations with alcohol use disorder. This study is highly innovative in three ways: 1) it is the first fully powered effectiveness trial of a proven smartphone app for alcohol cessation in ALD patients, 2) it will test a new model of care for delivering alcohol cessation treatment to ALD patients, and 3) it will utilize a novel collaboration of systems engineering and medical researchers with expertise in ALD, digital health, and implementation science. If successful, this study holds promise to provide critically needed alcohol use resources to ALD patients and potentially set a new standard of care.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY Developing an individualized approach to interpreting patient-reported outcome measures (PROM) scores is essential to providing quality care. In this proposal, we plan to create an individualized minimally clinically important difference (MCID) that is specific to each patient in order to improve the ability of PROMs to assess individual patient preferences and measure responsiveness to treatment in heterogeneous patient populations. Specifically, we will evaluate how clinically relevant information (e.g., baseline severity, sociodemographic characteristics) affects the interpretation of PROMs and how this information should be incorporated when making clinical decisions for individual patients. Unilateral vocal fold paralysis (paralysis) is a life-changing condition caused by injury to one recurrent laryngeal nerve and results in temporary or permanent glottal incompetence. Effects on health and quality of life can include loss of voice, swallowing dysfunction, and psychosocial distress. Paralysis is suited for developing the individualized MCID because (1) treatments exist, but effectiveness is poorly characterized; (2) decision-making is based on individual patient preferences; and (3) patient symptoms are heterogeneous, affected by injury severity and unique patient characteristics. Our team has pioneered statistical theory to develop the individualized MCID and simultaneously developed and validated the Cord Paralysis Experience (CoPE) – a novel PROM designed to assess disability specific to paralysis. The proposed study will develop an individualized MCID that incorporates each patient's injury severity, vocal demands, and sociodemographic characteristics, which can be used to improve the interpretability of PROMs at the point-of-care and align patient-provider expectations. To do this, we will perform an observational cohort study that measures pre- and post-treatment CoPE score changes among adults treated for acute paralysis (<3 months from injury, when symptoms are most severe) with standard-of- care interventions across a 37-site national collaborative of high-volume voice centers. The specific aims for this project are: (1) create individualized minimal clinically important differences (iMCID) that account for each patient's baseline injury severity, vocal demands, and sociodemographic characteristics, (2) test the heterogeneity of treatment effect among patients with acute paralysis to identify factors associated with treatment effectiveness of speech therapy and/or injection augmentation, and (3) develop a method to contextualize patient preferences using the iMCID with expected treatment effects in order to align patient- provider expectations. This work will revolutionize how the MCID is applied in heterogeneous patient populations while enabling clinical trials to improve the care of patients with paralysis, and making CoPE a useful, standardized way to assess disability in patients with paralysis at the point-of-care.

NIH Research Projects · FY 2025 · 2023-09

Project Summary The burden of Alzheimer’s Disease and Related Dementias (ADRD) is projected to increase by 150% by the year 2060 to affect 14 million Americans, with four- and seven-fold increases anticipated among Black and Hispanic/Latino older adults. To better understand the accumulation of risk throughout the life course and the disparities that exist in ADRD, studying social and structural determinants of health and employing a life course perspective have been emphasized. Research on the role of early life stressors and adversity on ADRD is emerging, but still limited. Older adults who experienced more childhood adversities had greater likelihood of incident dementia in three international aging cohorts; U.S.-based studies have been largely cross-sectional in design, mixed results have been observed, and only one examined racial/ethnic differences. However, greater understanding of the role these factors play is imperative if we aim to mitigate the risk of ADRD with a health equity lens. Identifying early life risk factors for ADRD and the primary pathways through which childhood adversity is operating will allow for more targeted interventions to reduce risk of ADRD in later life for the most vulnerable in our population. In addition, the role of neighborhood deprivation in these relationships remains understudied, despite known ramifications of environmental factors on health behaviors and outcomes. Understanding structural determinants of health and how they impact risk of ADRD will provide valuable insight for identifying the most vulnerable communities for targeting effective prevention strategies and motive for structural changes and policies that aim to improve these environments and the overall health of those individuals at greatest risk. To have the greatest impact on reducing the risk of ADRD, the role of the environment must be considered. In the F99-phase of this proposed research, Adrienne Lee will conduct three novel studies of these complex associations. Specifically, Adrienne will use the Health and Retirement Study to evaluate the associations of childhood adversity with neighborhood deprivation, cognitive trajectories, and dementia outcomes within racial/ethnic subgroups. She will link the study sample to the area deprivation index in midlife to further understand the role of environment and structural determinants of health on these associations, and to identify population-specific mechanisms by which we can tailor interventions throughout the life course. In the K00-phase of this proposed research, Adrienne will build off her dissertation research to identify early life resilience factors that promote healthy cognitive aging and that may counteract ACE exposure, and she will examine the associations of ACE exposure, in combination with neighborhood deprivation in relation to other hallmarks of aging. This research will inform equitable interventions.

NIH Research Projects · FY 2024 · 2023-09

PROJECT SUMMARY Alzheimer’s disease (AD) pathophysiology seldom occurs in isolation, and it is widely established from the neuropathology literature that the majority of individuals with dementia have multiple etiology dementia (MED). MED is common but undetected in extant major cohort studies and treatment trials for AD; many studies intentionally restrict clinical heterogeneity to an assumed single etiology by using narrowly defined clinical enrollment criteria. A major gap in our field is the lack of validated tools to detect MED in-vivo. The next era of large-scale imaging biomarker studies for AD and related disorders (ADRD) will require strategies commensurate with the known but largely unaddressed problem of etiologic heterogeneity. The Alzheimer’s Disease Research Centers (ADRCs) are uniquely positioned to meet this need. Collectively the 37 ADRCs follow ~14,000 active enrollees with high brain donor and autopsy rates (>60%). The ADRCs recruit across the clinical severity continuum and amply represent the several diseases comprising ADRD. Now, as a consortium, the centers will conduct a uniform imaging protocol capable of elucidating individualized etiological profiles including foundational PET imaging for AD proteinopathy (Amyloid and Tau), vascular burden with MRI and additional structural MRI and FDG PET for assessing the several patterns of morphologic and metabolic Neurodegeneration signatures of both AD and non-AD proteinopathies on deeply phenotyped patients. Design: This is a longitudinal imaging study at 2-year intervals that is superimposed on and fully integrated with the ongoing uniform cognitive and clinical data collection the 37 ADRCs already do. We will study 2,000 ethnoculturally diverse ADRC participants that are either clinically unimpaired (CU; N=800) or impaired (N=1,200) where AD is a considered, though need not be the primary suspected etiology. Aim 1 creates the ATN cohort through prospective imaging and plasma collection and establishes the foundational shared resource in conjunction with the National Alzheimer’s Coordinating Center (NACC) with linkage to the vast clinical, cognitive, and genetic datasets on these same participants. In Aim 2 we examine the temporal progression of the two most common etiologies—AD and vascular disease. We examine onset ages and duration of each and their joint effect on cognitive decline. Aim 3 focuses on other common proteinopathies. Classification and joint modelling methods will be applied to estimate etiologic composition and the effect of multi-proteinopathy on clinical and cognitive change. ATN imaging–a critical foundation for characterizing likely dementia etiologies—is needed on this expertly-diagnosed, uniformly evaluated MED ADRD cohort where neuropathology can inform clinicopathologic correlation, mechanistic underpinnings, and strategic diagnostic and therapeutic development. The consortium of ADRCs have the expertise and capacity to conduct this study and will work together to ensure its success and its impact on the field.

NIH Research Projects · FY 2024 · 2023-09

PROJECT SUMMARY Obesity, glucose and insulin resistance, and other metabolic disorders are on the rise due in part to the growing aged population. Dietary interventions such as calorie restriction (CR) can improve and even reverse these complications but CR diets are difficult for most people to adhere to. Alternative regimens based on restriction of specific macronutrients, such as protein restriction (PR) or limitation of specific essential amino acids, have shown promise in improving metabolic health and extend lifespan without needing to limit of calories. I and the Lamming lab have shown that Isoleucine restriction (IleR) improves glucose homeostasis, improve body weight and adiposity, and even extends the lifespan of mice. IleR induces fibroblast growth factor 21 (FGF21), an energy expenditure hormone and some but not all of the documented benefits of IleR are dependent on FGF21. During the F99 phase, I will determine for the first time if FGF21 is required for lifespan extending effects of IleR by using a mouse model of whole body FGF21 knockout. I will also test the necessity of mTORC1 in the adipose and skeletal muscle – two key sites of isoleucine catabolism – on IleR benefits by deleting Raptor specifically in the skeletal muscle or adipose tissue. This study will nicely bridge the gap between my graduate and postdoctoral work as I shift my focus from whole body metabolism and physiology to biology of aging muscle. In the K00 phase, I will utilize a validated mouse model of resistance exercise training to determine the interaction between training and the mTORC1 inhibitor rapamycin on skeletal muscle outcomes, such as muscle mass, fiber type, strength and mitochondrial respiration in both male and female mice of middle and old age, as well as organismal outcomes including frailty. I will also utilize banked tissues to examine muscular outcomes in older humans from a randomized clinical trial of everolimus Dr. Konopka has received funding for. Finally, I will conduct an exploratory analysis of the interaction between skeletal muscle health, everolimus, and dietary components based on the diet recall collected for each participant in the clinical trial. Completing these aims will bring me one step closer to my goal of becoming a well-rounded independent researcher conducting meaningful research on nutrition and metabolism in aging.

NIH Research Projects · FY 2026 · 2023-09

PROJECT SUMMARY Obesity, glucose and insulin resistance, and other metabolic disorders are on the rise due in part to the growing aged population. Dietary interventions such as calorie restriction (CR) can improve and even reverse these complications but CR diets are difficult for most people to adhere to. Alternative regimens based on restriction of specific macronutrients, such as protein restriction (PR) or limitation of specific essential amino acids, have shown promise in improving metabolic health and extend lifespan without needing to limit of calories. I and the Lamming lab have shown that Isoleucine restriction (IleR) improves glucose homeostasis, improve body weight and adiposity, and even extends the lifespan of mice. IleR induces fibroblast growth factor 21 (FGF21), an energy expenditure hormone and some but not all of the documented benefits of IleR are dependent on FGF21. During the F99 phase, I will determine for the first time if FGF21 is required for lifespan extending effects of IleR by using a mouse model of whole body FGF21 knockout. I will also test the necessity of mTORC1 in the adipose and skeletal muscle – two key sites of isoleucine catabolism – on IleR benefits by deleting Raptor specifically in the skeletal muscle or adipose tissue. This study will nicely bridge the gap between my graduate and postdoctoral work as I shift my focus from whole body metabolism and physiology to biology of aging muscle. In the K00 phase, I will utilize a validated mouse model of resistance exercise training to determine the interaction between training and the mTORC1 inhibitor rapamycin on skeletal muscle outcomes, such as muscle mass, fiber type, strength and mitochondrial respiration in both male and female mice of middle and old age, as well as organismal outcomes including frailty. I will also utilize banked tissues to examine muscular outcomes in older humans from a randomized clinical trial of everolimus Dr. Konopka has received funding for. Finally, I will conduct an exploratory analysis of the interaction between skeletal muscle health, everolimus, and dietary components based on the diet recall collected for each participant in the clinical trial. Completing these aims will bring me one step closer to my goal of becoming a well-rounded independent researcher conducting meaningful research on nutrition and metabolism in aging.

NIH Research Projects · FY 2025 · 2023-09

Project Summary We will develop new large-scale dynamic embedding models of network data with a focus on dynamic connec- tivity matrices from non-stationary multivariate time series obtained from human functional magnetic resonance images (fMRI). We propose to model brain networks as 2D curved surfaces, where the surface geodesics give connectivity information. Our approach will bypass the use of parcellations and more accurately evaluate the evolutionary dynamics of functional brain networks at the voxel level. We propose to build dynamically changing functional brain networks from a dataset with 1206 subjects from the Human Connectome Project (HCP) database containing T1-weighted magnetic resonance images (MRI), diffusion MRI (dMRI) and task and resting-state functional MRI (fMRI). MRI and dMRI will be used in conjunction with fMRI in building more refined dynamic connectivity models. Using 243 pairs of twins in the HCP database, we will determine network phenotypes specific to behavior, cognition and their genetic associations. This study will provide the research community with the brain network heritability maps and as well as a versatile open-source toolbox of algorithms for modeling and visualizing dynamically changing large-scale brain networks.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY/ABSTRACT Females with neurodevelopmental disabilities, including females with Down syndrome (DS), autistic females (iASD), and females with fragile X syndrome (FXS), are significantly understudied in research. Even though, like their male peers, females experience pervasive, lifelong difficulties with language, adaptive functioning, psychiatric comorbidities, and academic achievement, there remains a dearth of research regarding phenotypic development in females in these clinical groups. DS is the most common genetic cause of intellectual disability, while FXS is the most common inherited cause of intellectual disability and the most common single-gene cause of ASD. Both DS and FXS are associated with higher rates of co-occurring autism compared to the general population. Research on males has identified key areas of overlap and distinction between these three neurodevelopmental disabilities, particularly in language and cognition. Thus, studies comparing the phenotypes of DS, FXS, and iASD in females, focusing on areas of overlap and divergence, are particularly important because they provide the foundation for clinical and educational planning and elucidating the mechanisms producing the phenotypes of these three clinical disorders. Executive functions are one aspect of cognition that has received significant attention in DS, FXS, and iASD, since they are an important contributor to real-world outcomes and particularly amenable to treatment. Both language and executive functions are known to have a significant and pervasive impact on critical developmental outcomes, including academic skills (i.e., literacy), adaptive behavior, and psychiatric symptomatology. The impact of language and executive functions on these outcomes has not been explored in females with DS, FXS, or iASD. There is an urgent need to characterize the language and cognitive phenotypes of school-age females with these disorders to understand the nature and course of development. The proposed supplement will add a group of 20 8-12- year-old females with DS to the parent project, which includes 8–12-year-old females with FXS (n = 70) and iASD females (n = 70). Through two specific aims, we will determine the extent, nature, and syndrome specificity of impairments in language and executive functions and examine their relationships. We will determine the impact of language and executive functions on key developmental outcomes, including literacy, adaptive functioning, and psychiatric symptomatology. The proposed study will include standardized assessments, expressive language samples, experimental tasks, and parent report measures. The data from this study will provide critical information for clinicians and educators working with females with DS, FXS, and iASD and will provide data necessary for the development of targeted interventions for cognitive and language skills directly impacting developmental outcomes.

NIH Research Projects · FY 2024 · 2023-09

PROJECT SUMMARY/ABSTRACT Cardiac IKr is a critical repolarizing potassium current shaping the human ventricular action potential. It is conducted by heteromeric assemblies of the human ether-à-go-go-related gene (hERG1) 1a and 1b subunits. These subunits are encoded by alternate transcripts of the hERG/KCNH2 gene and differ only in their amino- terminal regions. hERG1a/1b heteromerization is vital for normal CM function, as the imbalance of subunit expression and/or function results in cellular pro-arrhythmic behaviors. hERG1a/1b assembly is mediated by the co-translational association of the encoding mRNAs in HEK293 cells, cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs), and human myocardium. Evidence suggests that interaction between the nascent proteins is not required for the co-translational complex assembly. This grant's preliminary findings indicate that this complex assembly occurs post-transcriptionally and is promoted by direct interactions between hERG1a and 1b mRNAs governed by their secondary structures. In preliminary studies, RNA binding proteins DDX3X and DDX5 were identified as part of the complex, and purified DDX3X promoted hERG1a/1b mRNAs' association in vitro. In the K99 phase, I will define the mRNA structural features promoting the co-translational association and determine the affinity and energies of the RNA/RNA interaction using in vitro systems, isothermal calorimetry (ITC), mutagenesis, hybrid protein-RNA immunoprecipitation (RIP), and live-cell imaging. I will also determine whether DDX3X and DDX5 affect hERG1a and 1b mRNAs stability, translation, and association in hiPSC-CMs using qPCR, electrophysiology, Western Blot, ribosome profiling, RIP, and single molecule fluorescent in situ hybridization (smFISH). I will use quantitative ITC and in vitro reconstitution approaches to determine the specificity, affinity, and energies of the interaction between purified DDX3X and DDX5 with hERG1a and 1b mRNAs. I will also evaluate if DDX3X and DDX5 promote the association of the mRNAs in in vitro systems. In the R00 phase, I will determine whether the stability, translation, and association of hERG1a and 1b mRNAs are impaired in arrhythmias associated with type 2 long QT syndrome (LQT2). I will use hiPSC-CM disease models to evaluate half-life, translation rate, and association of the mRNAs with qPCR, ribosome profiling, RIP, and smFISH. These experiments will contribute to understanding ion channel biogenesis and elucidate molecular mechanisms underlying LQT2 related arrhythmias. This proposal is designed to fulfill my short-term goals of expanding my skills in cardiovascular research and biophysics and transitioning into the independent phase of my career. This will ultimately allow me to obtain my long-term purpose of linking RNA and ion channel biophysics to translational cardiovascular research.

NIH Research Projects · FY 2024 · 2023-09

PROJECT SUMMARY/ABSTRACT This career development proposal is designed to provide Fred Ketchum, MD, PhD, with the necessary training to become an independent clinician-scientist developing interventions to improve decision- making and communication about preclinical biomarker testing that are inclusive to the needs of diverse patients with Alzheimer’s Disease and Related Dementias (ADRD). Dr. Ketchum will build upon his existing skills in qualitative research and medical communication to acquire additional skills in 1) user- centered design and implementation based on healthcare systems engineering approaches; 2) design and conduct of clinical trials of behavioral interventions with racially and ethnically diverse populations; 3) training in decision sciences. As an early-career researcher at an institution with an extensive infrastructure to support early-stage investigators and committed expert mentors, Dr. Ketchum is in an ideal environment to complete the proposed research and training. This proposal seeks to develop and pilot test an intervention to support decision-making about blood biomarker testing in primary care settings. Rapid advances towards blood biomarkers to screen for preclinical Alzheimer’s Disease are a major step towards addressing the devastating consequences of this condition by reducing diagnostic delays, broadening access for diverse populations, and ultimately allowing disease modifying therapies to be started sooner. Blood biomarker testing is expected to be used heavily by Primary Care Providers (PCPs), who make initial decisions about screening, diagnosis, and referral for patients with cognitive complaints. However, decisions about testing are complex, and there is a crucial need to support decisions among PCPs and their patients to address the gap between the future availability of biomarkers and integration into routine diagnostic decisions by PCPs, thereby advancing NIA’s strategic priority of developing effective interventions to address the burden of age- related diseases like ADRD. Aim 1 seeks to characterize decision-making processes related to clinical evaluations for cognitive complaints and identify decision-support needs among patients and PCPs. Aim 2 will adapt a decision-support tool for blood biomarker testing for use in diagnostic evaluations of cognitive complaints by PCPs in diverse populations through a user-centered design process. Aim 3 will test usability and acceptability of the intervention, and effects on shared decision-making. These data will support submission of an R01 proposal at the end of this award to determine the effects of the decision support tool on shared decision-making about blood biomarker testing in preclinical Alzheimer’s Disease in a large national sample.

NIH Research Projects · FY 2025 · 2023-09

PROJECT ABSTRACT Asthma is a complex, heterogenous condition with both genetic and environmental factors contributing to disease. The epithelial barrier is the interface between environmental exposures and the host. Gene- environment interaction studies demonstrate that early life exposures modify genetic risks in asthma, and epigenetic changes, such as DNA methylation (DNAm) may mediate these effects. Additionally, epithelial transcriptional changes link to childhood asthma. We propose to use both of these powerful technologies to provide a mechanistic link from environmental exposure to asthma inception. We hypothesize that exposures at the epithelial barrier related to the community (air pollution, nearby green space) and the individual (microbiome) alter epithelial DNAm and transcriptional responses to promote the development of asthma. To evaluate this hypothesis, we will leverage the ECHO Cohort protocol 3.0 to determine how prenatal and early life individual and neighborhood level exposures contribute to nasal epithelial changes in infancy to promote the development of wheezing (aim 1), determine how the these exposures, including the skin microbiome, influence skin epithelial changes to promote atopic dermatitis and wheezing (aim 2), and elucidate how individual and neighborhood characteristics influence maternal nasal epigenetic changes throughout pregnancy, and how these changes relate to allergic diseases in the child (aim 4). Finally, we will follow existing ECHO participants and recruit 350 pregnant women and 50 women preconception that give birth (for a of total 400 births) into ECHO Cohort protocol 3.0 (aim 3). Importantly, throughout this proposal, we seek to disentangle factors that may underlie health disparities by identifying the mechanisms by which environmental exposures (that are often associated and conflated with race) cause asthma. We will identify precise molecular targets for diagnosis and prevention. This information can be used to (1) establish non-invasive biomarkers (from nasal or skin swabs) to identify infants at risk for asthma, (2) develop treatment strategies based on altering patterns of microbial colonization or epithelial gene expression to promote health, and (3) identify actionable exposures that underly health disparities for intervention.

NIH Research Projects · FY 2024 · 2023-09

Project Abstract Dry mouth is a significant side-effect of radiation therapy for head and neck cancer patients. Several factors contribute to dry mouth. Decreased production of saliva is called hyposalivation. Poor quality and function of saliva is called salivary dysfunction. Together, these cause xerostomia, or what a patient experiences as simply dry mouth. Xerostomia can lead to tooth decay, infections, difficulty speaking, impaired swallowing, poor nutrition, and has a significant negative effect on quality of life. Doctors recommend that patients suck on hard candy, chew gum, use saliva substitutes, and/or carry a water bottle with them at all times. None of these are particularly effective. Our long-term goal is to prevent the development of long-term radiation-induced dry mouth to improve the quality of life for patients with head and neck cancer. We seek to achieve this goal by providing convincing evidence that innovative cellular therapies can safely and significantly prevent the development of long-term salivary gland dysfunction. The team of investigators tackling this project is uniquely suited to complete the work. Success would lead directly to the next phase of clinical testing. We have expertise in caring for head and neck cancer patients, developing minor salivary gland derived mesenchymal stromal cells (MSCs) as cellular therapies, and studying salivary function. The overall objective of this application is to plan and prepare for a Phase 1 trial to test the safety and tolerability of IFN-g pre-licensed minor salivary gland derived MSCs for prevention of radiation-induced xerostomia in head and neck cancer patients. To achieve our goals, we propose a milestone-based project in which we will work closely with the NIH and FDA to finalize study design for a Phase 1 safety and tolerability study, complete the clinical trial protocol, and submit regulatory documents in Aim 1. In Aim 2, we will complete all necessary milestones to activate the proposed clinical trial including safety systems, data systems, and site staff and facility preparation to ensure a smooth opening to the planned clinical trial.

NIH Research Projects · FY 2026 · 2023-09

Abstract Neuroinflammation, oxidative stress, and mitochondrial dysfunction have been associated with the pathophysiology of Alzheimer’s disease (AD), either as a primary cause or as a secondary component of the pathogenic process. AD, the most common cause of dementia in the elderly, is characterized by the accumulation of intracellular tau neurofibrillary tangles and extracellular amyloid plaques. The main component of the plaque core is the amyloid β (Aβ)-peptide. Longitudinal studies have shown that the appearance of plaques and tangles, together with markers of inflammation, starts decades before the onset of clinical symptoms. Some components of the inflammatory response may promote resolution and facilitate Aβ clearance, while sustained inflammation induces neurotoxicity. Fatty acid-binding proteins (FABPs) have recently emerged as key regulators of cell metabolism and inflammation. They control the intracellular transport of lipids that function as both, ligands for transcription factors and substrates for enzymes involved in lipid metabolism. In AD and other pathological conditions, astrocytes upregulate FABP7 expression. This increase in FABP7 expression has been linked to mitochondrial dysfunction. Accordingly, FABP7 is especially abundant in astrocytes that are rich in cytoplasmic granules originated from degraded mitochondria. Our preliminary data indicate that FABP7 participates in the development of a pro-inflammatory phenotype in human astrocytes, while down-regulation of FABP7 reduces the expression of inflammatory markers. FABP7 regulates the inflammatory response at least through 2 different mechanisms that have been independently pursued as therapeutic targets in AD. These include the regulation of peroxisome proliferator-activated receptor (PPAR) signaling and the regulation of arachidonic acid metabolism by cyclooxygenase-2 (COX-2). This suggests that FABP7 could function as a key regulator of the inflammatory response in astrocytes and constitutes a potential therapeutic target in AD. By simultaneously regulating two central components of the inflammatory response, targeting FABP7 may confer enhanced therapeutic efficacy over conventional anti-inflammatory therapies. On the aforementioned context, we will determine the mechanism by which FABP7 regulates the inflammatory response in astrocytes (Aim 1) and we will determine the therapeutic potential of targeting FABP7 in AD mouse models (Aim 2). Lastly in Aim 3 we will evaluate the extent to which FABP7 expression correlates with biomarkers of AD pathology and the rate of cognitive decline in human subjects. This proposal will contribute to the understanding of the role of FABP7 in neurodegeneration and will provide in vivo proof of the value of modulating FABP7 expression as a therapeutic target in AD.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY/ABSTRACT Epstein-Barr virus (EBV) is an important cause of human lymphomas in both immunocompetent and immunosuppressed humans, including Burkitt lymphomas (BLs), Hodgkin lymphomas (HLs) and diffuse large B cell lymphomas (DLBCLs). There are three different types of EBV latency (types I, II and III) that differ in the number of latent viral proteins expressed and transforming ability. Only type III viral latency (in which all 9 latent viral proteins are expressed) can transform primary human B cell in vitro, but because type III latency is highly immunogenic, EBV+ tumors with type III latency in humans are relatively rare and largely found in immunosuppressed hosts. EBV+ HLs and DLBCLs in humans commonly have type II latency (characterized by expression of EBNA1, LMP1 and LMP2A), while EBV+ BLs, which contain MYC translocations, have type I latency (in which EBNA1 is the only viral protein expressed). However, there is currently no in vivo or in vitro model available to study how EBV infection causes lymphomas with type I or type II latency, since this form of viral latency is not transforming in vitro and wild-type EBV-induced lymphomas in humanized mouse models inevitably support type III latency. EBNA2 transcriptionally activates each of the latent viral promoters used during type III latency. Using a newly constructed EBNA2-deleted EBV mutant (ΔEBNA2 EBV) made by our lab, we have developed a novel culture system that allows us to stably infect primary naïve B cells in vitro with this mutant, and to examine the effect of MYC over-expression. Our exciting preliminary results show that B cells infected with ΔEBNA2 EBV form DLBCL-like and HL-like tumors with type II viral latency at late time points in NSG mice, and that over-expressing the MYC gene (using a retroviral vector) in ΔEBNA2 EBV-infected B cells results in rapid onset of aggressive tumors that resemble human BLs and support type I EBV latency. In contrast, expression of MYC alone does not cause tumors in this model. As human BLs, DLBCLs and HLs are derived from germinal center (GC) B cells, in Aim 1, we will use this new model to examine the ability of ΔEBNA2 EBV- infected primary GC B cells (with or without MYC over-expression) to form lymphomas in NSG mice. In Aim 2, we will identify the specific EBV genes (and/or viral RNAs) required for the development of ΔEBNA2 EBV- induced tumors (with or without MYC) in naïve versus GC B cells. In Aim 3, we will define mechanisms by which MYC turns off LMP1 expression in ΔEBNA2 EBV-induced lymphomas and determine if small molecules that can restore LMP1 expression enhance the immune response to tumors in humanized mice. The proposed experiments will provide the first model system to define how types I and II EBV latency cause lymphomas in human GC B cells and to ask if restoration of LMP1 expression in BLs enhances the host immune response.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY Protein phosphatase 2A (PP2A) is a major Ser/Thr phosphatase with complex regulation and composition. Deregulation of PP2A holoenzymes leads to devastating human diseases, including multiple types of cancer and neurological disorders. In recent years, whole exome/genome sequencing for the molecular diagnosis identified broad disease mutations in PP2A subunits and substrates in cancer and neurological disorders. The diagnosis of de novo PP2A mutations in developmental disorders enthused unprecedented multidisciplinary phosphatase research and interactions with patient families. De novo mutations in several members of B56 family of PP2A regulatory subunits, such as B56δ and B56γ, cause neurological disorders, known as Jordan Syndrome. The same somatic mutations were found in cancer patients. Built on our preliminary cryo-EM, molecular dynamic simulations, biochemical, single molecule, reverse phase protein array, and cell biology studies, here we aim to decipher the mechanisms of B56 disease mutations in cancer and intellectual disabilities. We will determine the cryo-EM structures of WT and disease variants of the PP2A-B56δ holoenzyme (Specific Aim 1), investigate how intellectual disability (ID) mutations alter holoenzyme dynamics, activation phosphorylation, and interactions with regulatory proteins, combining biochemical dissections, advanced molecular dynamic simulation approaches, and single-molecule fluorescence resonance energy transfer (smFRET) (Specific Aim 2), and test our hypothesis on the discriminating and merging mechanisms of B56δ and B56γ ID mutations in perturbing the cAMP negative feedback signaling via MAPK and CREB signaling, respectively (Specific Aim 3). These studies will shed light on a highly dynamic regulation machinery involving the folding of long disordered regions against the holoenzyme core and a super-long dynamic interface harboring the majority of residues mutated in Jordan Syndrome, multiple activation phophorylation sites, and regulatory elements that suppress both the phosphatase active site and the substrate-binding groove.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY/ABSTRACT This career development proposal is designed to provide Fred Ketchum, MD, PhD, with the necessary training to become an independent clinician-scientist developing interventions to improve decision- making and communication about preclinical biomarker testing that are inclusive to the needs of diverse patients with Alzheimer’s Disease and Related Dementias (ADRD). Dr. Ketchum will build upon his existing skills in qualitative research and medical communication to acquire additional skills in 1) user- centered design and implementation based on healthcare systems engineering approaches; 2) design and conduct of clinical trials of behavioral interventions with racially and ethnically diverse populations; 3) training in decision sciences. As an early-career researcher at an institution with an extensive infrastructure to support early-stage investigators and committed expert mentors, Dr. Ketchum is in an ideal environment to complete the proposed research and training. This proposal seeks to develop and pilot test an intervention to support decision-making about blood biomarker testing in primary care settings. Rapid advances towards blood biomarkers to screen for preclinical Alzheimer’s Disease are a major step towards addressing the devastating consequences of this condition by reducing diagnostic delays, broadening access for diverse populations, and ultimately allowing disease modifying therapies to be started sooner. Blood biomarker testing is expected to be used heavily by Primary Care Providers (PCPs), who make initial decisions about screening, diagnosis, and referral for patients with cognitive complaints. However, decisions about testing are complex, and there is a crucial need to support decisions among PCPs and their patients to address the gap between the future availability of biomarkers and integration into routine diagnostic decisions by PCPs, thereby advancing NIA’s strategic priority of developing effective interventions to address the burden of age- related diseases like ADRD. Aim 1 seeks to characterize decision-making processes related to clinical evaluations for cognitive complaints and identify decision-support needs among patients and PCPs. Aim 2 will adapt a decision-support tool for blood biomarker testing for use in diagnostic evaluations of cognitive complaints by PCPs in diverse populations through a user-centered design process. Aim 3 will test usability and acceptability of the intervention, and effects on shared decision-making. These data will support submission of an R01 proposal at the end of this award to determine the effects of the decision support tool on shared decision-making about blood biomarker testing in preclinical Alzheimer’s Disease in a large national sample.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY/ABSTRACT Bacteria often grow in close association with solid surfaces. Tissues of the human body such as the oral cavity, lungs, gut and skin serve as surfaces for colonization by pathogenic bacteria that cause a significant health burden. Despite the importance of surface-associated bacteria to the development of infections, therapeutic interventions that target attached cells remain scarce. My laboratory seeks to understand fundamental mechanisms of how bacteria colonize surfaces. Bacterial cells growing on surfaces display a variety of distinct physiological characteristics that we refer to collectively as the surface-adapted state. In recent years, the ability of bacteria to recognize contact with solid substrates has emerged as a critical activator of the surface-adapted state. A molecular machine called the flagellum participates in these surface sensing systems, but how the flagellum allows bacteria to respond to physical contact has been difficult to characterize. We recently used a genetic screen to identify dozens of genes that allow the model bacterium Caulobacter crescentus to respond to surface contact. Preliminary data collected in my laboratory show that these novel surface sensing factors link the flagellum to cellular process that are not encompassed by current models for surface colonization. The goal of the work proposed here is to define how the flagellum coordinates diverse regulatory systems in the cell to control surface adaptation. We will achieve this goal by (1) elucidating how chemotaxis and mechanosensing intersect to promote surface responses and (2) determining how surface contact influences cell cycle progression. The proposed studies leverage my group’s novel insights into the genetic basis for surface adaptation to define how bacterial cells respond to physical contact. Successful completion of this work will identify therapeutic targets for treating bacterial infections.

NIH Research Projects · FY 2025 · 2023-09

ABSTRACT Aneuploidy, the state in which cells carry an incorrect number of chromosomes, is a major problem for human health. Aneuploidy is toxic during mammalian development and a leading cause of pregnancy loss. Down syndrome (DS) due to trisomy 21 is one of the few viable aneuploid syndromes, but affected individuals have life-long problems including premature aging. Despite intense study, the reasons for aneuploidy toxicity are still incompletely understood, presenting challenges for understanding DS. In contrast, aneuploidy is very common in human cancers, where most tumors tolerate and may even benefit from extra chromosomes. It is unclear how cancer cells overcome the stress of aneuploidy, because we don’t fully understand how aneuploidy affects cells in the first place. This proposal will utilize an extremely powerful and unique system to study the consequence of aneuploidy in an important model system, wild strains of budding yeast Saccharomyces cerevisiae. Yeast is a powerful model for dissecting cellular biology, because many of the mechanisms and defense strategies are conserved in humans. We recently made an exciting discovery that chromosome duplication in healthy yeast strains disrupts nutrient responses and quiescence, a conserved cellular program important for growth control and cell maintenance and renewal. Strains of multiple genetic background and carrying different chromosome amplifications display shared phenotypes, including incomplete cell-cycle arrest upon nutrient depletion, metabolic aberrations, defects in quiescence-induced silencing, and ultimately reduced chronological life span. This is remarkable, because defects in similar markers of quiescence are seen in both DS and many cancers – if disruption of quiescence is a conserved response to aneuploidy, it could have transformative impacts for future studies. This grant will elucidate how aneuploidy disrupts quiescence in an important eukaryotic model system. Aim 1 will use dynamic transcriptomics and single-cell microscopy to characterize the temporal order of defects, test several initial hypotheses, and implicate upstream regulators. It will also distinguish common versus chromosome-specific effects. Aim 2 will use a barcoded plasmid over-expression library to identify genes that complement aneuploid defects along the progression to quiescence. Integrating Aim 1 and 2 results will define a temporal map of genes and processes defective in aneuploid yeast strains and involved in quiescence. It will also point to the upstream defect(s) directly caused by chromosome duplication, whose further study will expand our understanding of aneuplodiy Aim 3 will use genomic, proteomic, single-cell and single-molecule analysis to define and characterize the “Ssd1 Q granule”, a phase separated granule containing the RNA-binding protein Ssd1, which we previously showed is fundamental for aneuploidy tolerance in healthy yeast. Since many mechanisms in yeast are conserved in higher organisms including humans, this project will expand our basic understand of aneuploidy and have far-reaching impact relevant for multiple human diseases.

NIH Research Projects · FY 2025 · 2023-09

Project Summary Sleep is a fundamental biological process that is essential for survival in animals. Humans normally spend ~ 30% of our lifetime sleeping, but sleep disorders are prevalent in modern societies. Sleep abnormalities not only affect daily performance but also lead to adverse effects on neuronal function and contribute to neurological and other diseases. Thus, it is imperative to understand how and why we sleep. However, it remains largely unclear how sleep is controlled at the molecular, cellular, and circuit levels, partially due to the complexity of sleep regulation. A fundamental question about sleep is how the brain controls different sleep-associated behavioral changes to induce a robust sleep state. Our long-term goal is to build a comprehensive understanding of basic genetic pathways and neural mechanisms underlying sleep regulation. Sleep is an evolutionarily conserved process, with shared features across different organisms that include behavioral quiescence, increased arousal threshold, and rapid reversibility to wakefulness. In line with this, recent studies in simple model organisms, such as worms, fruit flies, and zebrafish, have yielded valuable insights into sleep regulation. We propose to study a simple and robust stress-induced sleep (SIS) state in C. elegans: cellular stress activates epidermal growth factor (EGF) signaling primarily within a single neuron (ALA) to induce sleep. How does a single neuron control a 302-neuron brain to drive C. elegans into a sleep state? To address this question, we will exploit the advantages of C. elegans, such as powerful genetics, short life cycle, optical transparency, and a compact nervous system. Our central hypothesis is that activation of EGF signaling in the ALA neuron induces sleep through the actions of distinct yet potentially overlapping molecular pathways and neural circuits that coordinate various sleep behavioral phenotypes. To test this hypothesis, we propose two projects: 1) perform a set of genetic screens and mutant analyses to identify new sleep regulatory genes and 2) perform brain-wide functional circuit mapping to identify the neural basis for SIS at single-neuron resolution. We will systematically manipulate and visualize the activity of individual neurons in the entire nervous system of C. elegans through a combination of optogenetics, chemogenetics, in vivo calcium imaging, and a powerful GAL4-based bipartite expression system (cGAL) we developed. The proposed research is significant because it will provide a mechanistic view of how sleep operates at the molecular, cellular, and circuit levels. This study will also potentially transform approaches of functional circuit analyses in C. elegans because the cGAL reagents produced in this study will become a powerful resource for the entire research community and can be readily used to dissect underlying neural circuits for other behaviors.

NIH Research Projects · FY 2024 · 2023-09

ABSTRACT Biological mechanisms underlying psychosocial stress-induced changes to the larynx remain understudied. Psychological stress symptomology is concurrently reported in 25% of patients with voice problems. From a biological perspective, psychosocial stress can have deleterious consequences on both microbial communities and epithelial barrier integrity, as reported, in other mucosal organs such as the gut and stomach. First, the laryngeal microbiome has a distinct microbial composition when compared to the gut. How this distinct composition is influenced by psychosocial stress remains unknown. Independently, stress-induced changes to epithelial permeability (such as reduced epithelial proliferation and reduced mucus thickness) may potentially leave the larynx susceptible to further infection. This proposal broadly questions whether psychosocial stress can lead to microbial dysbiosis and compromised epithelial barrier integrity. In our proposed experiments, mice will be assigned to unstressed or stressed groups. Psychosocial stress will be induced via a validated chronic restraint stress protocol. Specific Aim 1 will determine laryngeal microbial adaptations following chronic, psychosocial stress exposure. We hypothesize that psychosocial stress will result in reduced microbial diversity and abundance, altered composition and differential abundance of specific bacterial taxa, and distinct predicted functional profiles in the laryngeal microbiota. To obtain laryngeal microbiota outcomes, 16s rRNA sequencing will be used completed on bacteria extracted from murine laryngeal tissue. Specific Aim 2 will delineate changes in vocal fold epithelial integrity post-chronic psychosocial stress. We hypothesize that psychosocial stress will result in increased bacterial translocation, decreased mucus thickness, reduced epithelial proliferation, reduced epithelial cell junction integrity, and altered gene expression of mucins in the vocal folds. Immunohistochemistry/ Immunofluorescence and qPCR will be used to delineate consequences of psychosocial stress on the laryngeal epithelium. Taken together, we hypothesize that psychosocial stress will concomitantly lead to microbial dysbiosis and alter epithelial barrier integrity in the larynx. Data from these two aims will lay the groundwork for identifying and manipulating specific bacterial phyla to delineate host-microbial epithelial interactions of psychosocial stress in the larynx.

NIH Research Projects · FY 2026 · 2023-09

Project Summary The hematopoietic stem cell (HSC) microenvironment in the bone marrow, termed the niche, provides a specialized microenvironment to control the proliferation, self-renewal, differentiation and migration of HSCs. HSC aging is accompanied by an expansion of myeloid-biased HSCs with declined self-renewal functions. Aging of HSCs is associated with various age-related blood diseases, such as clonal hematopoiesis of indeterminate potential (CHIP). Whether the aged microenvironment drives the aging of HSCs and age-related hematologic diseases, however, remains unclear. I recently demonstrated that the nociceptive nervous system is an essential HSC niche component that regulates granulocyte colony-stimulating factor (G-CSF)-induced HSC mobilization via the secretion of neuropeptide calcitonin gene-related peptide (CGRP) in the bone marrow. Our preliminary data reveal a significant reduction of CGRP levels in the aged bone marrow microenvironment, and administration of CGRP attenuates aging-associated phenotypes of HSCs in the old mice, resulting in a reduced number of HSCs and a restored myeloid versus lymphoid balance. In addition, we find that aged bone marrow microenvironment promotes the clonal expansion of genetically mutated HSCs (Asxl1tm/+ HSCs) over wildtype HSCs. Based on these preliminary data, we propose a 5-year experimental plan to characterize the functions of nociceptive neurons in the aged bonne marrow microenvironment and to dissect the contributions of aged bone marrow microenvironment to clonal hematopoiesis. In Specific Aim 1, we will evaluate the impact of aging on nociceptive neurons in the bone marrow. We will determine whether aging induces the loss of nociceptive fibers or reduces the CGRP levels without affecting the nociceptive innervation in the bone marrow. We will explore the mechanisms by which nociceptor-derived CGRP signals in the bone marrow drive the aging of HSCs. We will investigate whether modulation of CGRP signaling via ingestion of food containing capsaicin – a natural component of chili peppers that could trigger the activation of nociceptive neurons – could rejuvenate the functional and molecular aging signatures of HSCs. In Specific Aim 2, we will determine how aged bone marrow microenvironment interacts with HSCs to promote the Asxl1tm/+ mutant clonal hematopoiesis and explore whether targeting the aged bone marrow microenvironment could prevent Asxl1tm/+ HSC expansion. These proposed studies, focusing on the interactions between bone marrow niche and HSCs, will allow us to identify new extrinsic factors regulating HSC aging and potentially provide novel approaches to rejuvenate HSCs and prevent age- related hematologic diseases.

NIH Research Projects · FY 2024 · 2023-09

PROJECT ABSTRACT Asthma is a complex, heterogenous condition with both genetic and environmental factors contributing to disease. The epithelial barrier is the interface between environmental exposures and the host. Gene- environment interaction studies demonstrate that early life exposures modify genetic risks in asthma, and epigenetic changes, such as DNA methylation (DNAm) may mediate these effects. Additionally, epithelial transcriptional changes link to childhood asthma. We propose to use both of these powerful technologies to provide a mechanistic link from environmental exposure to asthma inception. We hypothesize that exposures at the epithelial barrier related to the community (air pollution, nearby green space) and the individual (microbiome) alter epithelial DNAm and transcriptional responses to promote the development of asthma. To evaluate this hypothesis, we will leverage the ECHO Cohort protocol 3.0 to determine how prenatal and early life individual and neighborhood level exposures contribute to nasal epithelial changes in infancy to promote the development of wheezing (aim 1), determine how the these exposures, including the skin microbiome, influence skin epithelial changes to promote atopic dermatitis and wheezing (aim 2), and elucidate how individual and neighborhood characteristics influence maternal nasal epigenetic changes throughout pregnancy, and how these changes relate to allergic diseases in the child (aim 4). Finally, we will follow existing ECHO participants and recruit 350 pregnant women and 50 women preconception that give birth (for a of total 400 births) into ECHO Cohort protocol 3.0 (aim 3). Importantly, throughout this proposal, we seek to disentangle factors that may underlie health disparities by identifying the mechanisms by which environmental exposures (that are often associated and conflated with race) cause asthma. We will identify precise molecular targets for diagnosis and prevention. This information can be used to (1) establish non-invasive biomarkers (from nasal or skin swabs) to identify infants at risk for asthma, (2) develop treatment strategies based on altering patterns of microbial colonization or epithelial gene expression to promote health, and (3) identify actionable exposures that underly health disparities for intervention.

NIH Research Projects · FY 2026 · 2023-08

Abstract/Summary Considerable efforted is devoted to developing HIV cure regimens that reduce viral reservoirs and boost antiviral immunity. These interventions seek to permit people with HIV (PWH) to stop ART and durably control HIV, inducing sustained ART-free remission. However, the virologic and immunologic determinants of ART- free remission are poorly understood. Therefore, one of the enduring questions for HIV cure research is how far interventions must reduce viral reservoirs to attain clinically relevant periods of ART-free remission. It is a common assumption among the HIV research community that the size of HIV reservoirs at ART termination affects the time to viral rebound (TTR) and the capacity of antiviral immune responses to control virus replication. Yet, the association between reservoir size and TTR is unknown, and the immunologic basis of post-treatment viral control (PTC) is unclear. Nevertheless, it is challenging to address these fundamental questions in human clinical trials due to variability in patient groups and difficulty quantifying extremely small viral reservoirs in vivo. As a result, mathematical models have been developed to forecast PTC and TTR after stopping ART. These models predict that viral reservoirs must contain hundreds to thousands of HIV latently infected cells to delay viral rebound for a few months, and the size of latent reservoirs dictates whether antiviral immune responses can control HIV replication after stopping ART. However, validating these predictions in PWH is challenging. Thus, to empirically test these predictions, we will use a simian immunodeficiency virus (SIV)/rhesus macaque model to precisely set the size of latent reservoirs in vivo. To do so, we will infuse defined numbers of autologous in vitro generated SIV latently infected cells into ART-treated, SIV-naïve rhesus macaques. Further, we will determine the number of latently infected cells that reactivate after stopping ART by establishing reservoirs with genetically barcoded SIV. Therefore, we will use this novel latency model to determine how progressively smaller SIV reservoirs affect TTR and PTC in the presence or absence of antiviral immunity. Specific Aim 1: Determine the TTR for defined SIV viral reservoirs. In this Aim, we will determine the TTR for viral reservoirs containing 5e4, 1e4, 1e3, and 1e2 latently infected cells. Specific Aim 2: Determine the impact of viral reservoir size and antiviral immunity on TTR and PTC. In this Aim, we will induce antiviral immunity with recombinant rhadinovirus encoding near full-length SIV and determine the TTR and viral loads post-ART for reservoirs containing 5e4 and 1e3 latently infected cells.