University Of Southern California

NIH Research Projects · FY 2024 · 2020-08

PROJECT SUMMARY This project is proposed to respond to Provocative Question 6 in RFA-CA-19-032. Objective: Paracrine transformation is a theoretical concept that was proposed years ago to explain the unconventional “non-autonomous” oncogenesis observed during development of Kaposi’s sarcoma (KS), one of the most common AIDS-associated malignancies. This proposal is designed to prove its existence, to dissect its mechanism, identify the players therein, and to define its roles in KS tumorigenesis using our novel animal models and an engineered microphysiological platform. Rationale: Kaposi’s sarcoma herpes virus (KSHV) causes an endothelial cell tumor, KS, in the skin and internal organs. A paradox in KS oncogenesis is that while most KS tumor cells are latently infected with minimal viral gene expression, only lytic-stage cells express vGPCR, the only known viral oncogene that is necessary and sufficient for KS development. Provocative Question: How vGPCR, a lytic viral gene expressed in cells destined to die, can cause cancer? Challenges: This question remained unanswered due to the lack of proper animal models, engineered in vitro or ex vivo systems to study pathogenesis, persistence, and tumor development that recapitulate this HIV/AIDS- associated malignancies. Innovation & Strategy: We have developed a series of novel animal models and Vascularized Skin Chip platform. Using these technical advancements, we will prove the existence of paracrine transformation, identify its cellular (immune cells, HIV) and molecular (vGPCR-loaded exosome) players, and characterize its mechanism as the main oncogenic driver for KS tumorigenesis. Impact: Our study will address the decades-long conundrum on KS tumor development by defining the existence and mechanism of paracrine transformation. This provocative concept of paracrine transformation will not only force us to move our focus beyond the lytic-infected cells as the oncogenic drivers, but also expand the way we understand the initiation, progression, and metastasis of cancer. In addition, this study will open a new door to novel anti-KS therapeutics, and provide a solid justification to investigate the presence of equivalent non-autonomous transformation in other non-viral oncogenesis, such as breast and colon cancers.

NIH Research Projects · FY 2026 · 2020-08

Project Summary Initially funded in 2019, the Institute on Methods and Protocols for Advancement of Clinical Trials in ADRD (IMPACT-AD) course has been a highly successful effort to train the next generation of Alzheimer’s Disease (AD) and Related Disorders (AD/ADRD) clinical trialists. In four completed years of this competitive course, we have trained 151 investigators. Despite these successes, the vision for IMPACT-AD has not yet been fully realized. That vision is of an alumni scholar network of well-trained AD/ADRD clinical trialists with the leadership, technical, and scientific skills and connections necessary to carry the field forward, toward its goal of developing safe and effective therapies to prevent and halt all neurodegenerative causes of cognitive impairment. Trialists are infrequently supported or rewarded in academic settings, with still inadequate recognition of the value in leading trials locally or nationally and resultant difficulties in securing promotions or other career advances. Moreover, though the IMPACT-AD course has finally (in 2022 and 2023) been held in person after being forced to be held remotely by Zoom due to the COVID-19 pandemic, the opportunities for IMPACT-AD alumni scholars to connect with each other to build collaborations and research partnerships are highly limited. IMPACT-AD alumni scholars need continued training, mentoring, and opportunities to strengthen their network. Given these facts, we propose to repurpose this U13 award to address the critical needs of the IMPACT-AD alumni scholars by convening an annual IMPACT-AD Alumni Scholar Conference. The objectives of this Alumni Scholar Conference are to: 1) Provide IMPACT-AD alumni scholars additional training and skills to support their scientific and career advances, and 2) Enhance the network of IMPACT-AD alumni scholars by facilitating deeper knowledge of others in the network to enhance scientific collaboration.

NIH Research Projects · FY 2025 · 2020-08

ABSTRACT Sedentary behavior (SB) contributes to increased risk for obesity and metabolic disease, cognitive deficits, and affect disorders over the lifespan. These are critical outcomes because children with these risk factors are more likely to develop type 2 diabetes mellitus (T2DM). SB increases T2DM risk by promoting hyperglycemia and greater postprandial glycemic variability as well as via cognitive detriments and depressive symptoms that lead to poor energy balance behaviors, obesity, and worsening insulin resistance. Physical activity can reduce these risk factors, however less than half of US youth meet guideline recommendations, and physical activity continues to decline throughout adolescence. Thus, there is a critical need to test alternative intervention approaches to sustained bouts of exercise for the prevention of T2DM in children. We were the first to show that interrupting SB with short, 3-minute, bouts of moderate exercise improved glucose tolerance and negative mood in a single 3-hour session. However, it is unknown whether these short-term improvements translate to sustained multi-day benefits to metabolic, cognitive, and mood outcomes. Thus, the overall goal of this study is to test the efficacy of multi-day effects of interrupting SB as a T2DM prevention strategy in youth with overweight/obesity. We propose a Phase II RCT to compare the effects of SB interruptions vs. sustained bouts of exercise to prolonged sitting in 7-11-year-old children with overweight/obesity. This proposal will address the following aims: (1) determine the multi-day efficacy of interrupting sitting on glucose homeostasis measured by continuous glucose monitor and oral glucose tolerance tests; (2) determine the multi-day efficacy of interrupting sitting on cognitive function improvements; and (3) determine the multi-day efficacy of interrupting sitting on affect and anxiety improvements. This study is innovative because: (a) interrupting SB is a novel intervention strategy that has shown potential to acutely improve metabolic parameters, yet the longer-term effects are unknown and no prior studies have compared efficacy in reducing multiple T2DM risk factors using this approach vs. a single bout of exercise over multiple days in children; (b) the use of continuous glucose monitoring is a novel strategy to investigate multi- day glucose responses to SB interruptions and their association with cognitive and affective outcomes; and (c) investigating psychological responses to multiple days of interrupting SB vs. a single bout of exercise are novel outcomes that co-vary throughout the day, and are essential to elucidate if we are to develop novel intervention approaches that address factors associated withT2DM risk. Given the improvements in glucose homeostasis in our acute 3-hour trials, along with the dearth of pediatric studies investigating sustained interventions interrupting SB, this study is a significant and logical next step towards testing the efficacy of this approach for the reduction of multiple T2DM risk factors in children with overweight/obesity. Our approach is impactful because the rigorous, controlled lab setting will allow us to design stronger intervention strategies for children that can be translated to other settings, and age and weight groups, thereby contributing to efforts at reducing T2DM risk in U.S. youth.

NIH Research Projects · FY 2025 · 2020-08

Project Summary: Stem cells replenish tissues and organs over an organism’s lifetime and can repair damage after injury. With their special capacities for self-renewal and differentiation, stem cells promise to revolutionize medicine. To develop better and safer stem cell therapies, it is critically important to improve the understanding of stem cell regulation. Most of the knowledge about stem cell regulation comes from studies that investigate the aggregate behaviors of thousands to millions of stem cells. However, recent studies suggest that individual hematopoietic stem cells (HSCs) behave substantially differently from one another in both mice and humans. These newly discovered inter-cellular differences present exciting new opportunities for studying HSC regulation. However, they also present significant technical challenges that are difficult to address with conventional approaches. The proposed research program will use a novel systems biology approach combined with quantitative single-cell analysis to determine the cellular and molecular mechanisms underlying HSC heterogeneity and coordination, as well as their influences on aging and the pathogenesis of hematopoietic diseases. Many hematopoietic diseases—such as bone marrow failure, myeloproliferative disorders, myelodysplastic syndromes and other age-associated hematopoietic problems—are initiated by rare cells. The proposed research program will map the precise pathogenesis of these diseases and identify disease founder clones and genes using newly developed single cell tracking and molecular profiling technologies. With these technical advances, the proposed research will also produce new fundamental knowledge about blood regeneration, the foundation of bone marrow transplantation. The long-term objective is to apply the knowledge obtained from the proposed basic research to control blood regeneration for therapeutic use, to detect leukemia and other clonal diseases at early stages, and to effectively treat diseases with advanced stem cell therapies.

NIH Research Projects · FY 2026 · 2020-07

The Center for Advancing Sociodemographic and Economic Study of Alzheimer’s Disease and Related Dementias (CeASES ADRD), established in 2020 at the University of Southern California, is a leader in fostering a network of social science researchers and driving innovative health and health economics research on dementia to improve individual and societal well-being. Through innovative programming, research and communication for impact, CeASES ADRD built a network of over 300 research affiliates, collaborated with 8 NIH-funded centers to produce 12 workshops and webinars, hosted 8 visiting scholars, fostered 5 collaborative NIA grants, funded 17 pilot studies that led to 14 R applications submitted to NIA, 5 funded R01s and produced numerous high impact publications. Activities proposed in the current renewal application build on our strengths and move research forward, through growing and deepening research networks and convenings, supporting early stage scholars through pilot awards coupled with transformative mentorship, developing and supporting new data resources, integrating advanced methods from computer science into social science dementia research, and building the model infrastructure for leveraging the large and growing number of harmonized global aging studies to address central questions about the causes and consequences of dementia. Effective leadership will connect core activities and link NIA resources across our partner centers and other NIA funded Aging Centers. New web-based, interactive portals, and adoption of new technologies such as computer emulation will expand impact to research, and public audiences. We will move innovative dementia research forward across four research themes: (1) estimating social and economic impact of AD/ADRD; (2) improving healthcare payment and delivery systems; (3) promoting value in dementia care; (4) addressing the global dementia burden through dynamic microsimulation models. To do so, CeASES ADRD brings data, programming and external affairs resources from the USC Schaeffer Center for Health Policy and Economics and the resources from the new Schaeffer Institute together with our 11 NIA-funded Partner Centers including USC’s Resource Center for Minority Aging Research, Alzheimer’s Disease Research Center, Roybal Center, Gateway to Global Aging Data, and Gateway Exposome Coordinating Center. Multidisciplinary researchers from across schools of gerontology, medicine, engineering, arts and sciences at the University of Southern California and the University of Texas, Austin weave together strengths in innovative dementia research, mentorship, rigorous dynamic microsimulation, quasi-experimental and machine learning methods, and application of myriad population level, longitudinal data sets to generate impactful AD/ADRD social science research.

NIH Research Projects · FY 2025 · 2020-07

ABSTRACT Stroke in small brain vessels in subcortical white matter (WM) regions account for 25% of all strokes. It leads to vascular cognitive impairment and dementia (VCID), and is the second leading cause of dementia overall. Despite such clinical importance, the pathophysiology of ischemic WM injury (WMI) and VCID is still poorly understood. Moreover, there is no yet an approved therapy for prevention and/or treatment of WM strokes and VCID. Here, we propose collaborative studies between the Zlokovic and Griffin labs on activated protein C (APC) pathways in the WM, and to evaluate therapeutic potential of APC-based therapies for ischemic WMI using a model of vasoconstriction of small brain vessels in the WM. Our previous studies using models of large artery infracts, brain trauma and neurodegeneration led to discovery of vasculoprotective, blood-brain barrier (BBB)-stabilizing, neuroprotective, and anti-inflammatory activities of APC and its cytoprotective-selective mutants. In 2019, these findings have been translated into successfully completed phase 2 trial for ischemic stroke of 3K3A-APC, a 2nd generation cytoprotective-selective APC analog with >90% loss of anticoagulant activity. However, whether activation of APC pathways in the WM is beneficial or not during ischemic WMI, remains unknown. Our goals include: 1) providing proof of concept for hypothesized mechanisms for protective activities of APC in the WM; and 2) characterizing novel protease activated receptor 1 (PAR1)-related P1-47 and PAR3-related P3-42 APC-mimetic peptides, and 3) testing improved 3rd generation APC R-46-selective biologics for treating and preventing ischemic WMI and WM stroke. Our pilot data support our hypotheses that: i) APC will be beneficial for ischemic WMI via PAR1 cleavage at Arg46 to protect WM fiber tracts, oligodendrocytes and BBB from ischemic WMI (AIM 1); ii) APC-mimetic peptides derived from PAR1 and PAR3 sequences (e.g,, P1-47 and P3-42, (i.e., the tethered PAR agonists created by APC cleavages) exhibit synergistic biased agonism, and will elicit -arrestin 2-dependent cytoprotective signaling in brain endothelium and oligodendrocytes in vitro and in vivo after WM stroke (AIM 2); and iii) E56K-APC and D180E-APC newly engineered APC mutants have enhanced ability to cleave PAR1 at Arg46 and will provide improved APC biologics for WM stroke therapy (AIM 3). To address our hypotheses, we will use i) WM model of stroke; ii) new mouse lines carrying R41Q-PAR1 and R46Q-PAR1 point mutations, and -arrestin 2-/- and G12-/- mice; iii) new APC-mimetic PAR1- and PAR3-related peptides with the respective PAR1 and PAR3 tethered-ligand amino acid sequences; iv) new APC R46-cleavage site selective biologics; v) in vivo mutiparametric longitudinal MRI of WM lesion volume, BBB integrity, blood flow, structural and connectivity changes, and tract-tracing based connectomics for circuit level analysis; vi) behavior tests; vii) immunohistology, neuropathology; and viii) oligodendrocyte cultures and in vitro BBB model. If successful, new knowledge generated from this project could translate to the clinic as new therapies for WM stroke and VCID.

NIH Research Projects · FY 2025 · 2020-07

The proposed project is designed to evaluate the effectiveness of cefixime (400mg, twice a day, for 10 days) compared to benzathine penicillin G (2.4 million units, intramuscularly) in patients with and without HIV infection. Syphilis rates have been increasing both in the US and internationally. Incidence is higher among men-who-have-sex-with-men and more importantly in individuals with HIV infection. Currently, penicillin is used to treat syphilis in patients with and without HIV infection. Doxycycline, tetracycline and ceftriaxone are alternative treatments for non-pregnant patients who are allergic to penicillin. Existing treatment alternatives are based on clinical experience, a limited number of small clinical trials, and case series, but each poses clinical challenges. New, safe and efficacious antibiotic treatment options are needed. In this proposal, we will build upon our successful pilot study to conduct a randomized, multisite, open-label, noninferiority clinical trial to evaluate the effectiveness of cefixime (400mg, twice a day, for 10 days) compared to benzathine penicillin G (2.4 million units, intramuscularly) in patients with and without HIV infection. We will enroll 360 participants with early syphilis infection from 9 clinical sites in the U.S. We will follow the participants to monitor clinical progress and serological response (RPR titer) every 3 months for 9 months. Our hypothesis is that cefixime will be non-inferior to penicillin in treating syphilis, shown as a 4-fold decrease in RPR titer from enrollment to 6-months after treatment administration. These are the two specific aims of our proposal. AIM 1: Evaluate the effectiveness of cefixime in the treatment of early syphilis when compared to benzathine penicillin G. AIM 2: Determine the predictors of treatment failure among participants. RELEVANCE (See instructions):

NIH Research Projects · FY 2026 · 2020-07

Abstract Protein ADP-ribosylation is a complex and highly dynamic process controlled by distinct writer, reader and eraser proteins. As major intracellular writers, poly-ADP-ribose polymerases (PARPs) are responsible for catalyzing this key type of post-translational modification by using nicotinamide adenine dinucleotide (NAD+) as a co-substrate and play pivotal roles in regulating a significant number of physiological and pathophysiological events. By specifically recognizing ADP-ribosylated proteins, reader proteins can trigger downstream signaling cascades or effector functions in direct or indirect manners. Eraser proteins can modulate ADP-ribosylation- mediated signaling activities through rapid removals of covalently attached ADP-ribose unit(s). The writers, readers, and erasers constitute ADP-ribosylation-based interaction networks that are not only extensively involved in human health but also implicated in pathogenesis of numerous diseases. Despite technological advancement, little information is known regarding the ADP-ribosylation-dependent interactome under physiological conditions for individual PARP writers of interest. Moreover, few chemical probes with sufficient specificity are available for unambiguously studying disease-relevant PARP isoforms. The goals of this MIRA project are to develop novel chemical tools to address these major challenges and functionally and mechanistically dissect ADP-ribosylation-regulated networks across varied cellular contexts. Successful completion of this work will result in a set of innovative chemical probes for in-depth studies of ADP-ribosylation- mediated signaling and advance our understanding of functions and roles of protein ADP-ribosylation in physiology and pathophysiology, leading to potential major breakthroughs in the development of new diagnostics and therapeutics targeting ADP-ribosylation-associated activities and pathways for many human diseases.

NIH Research Projects · FY 2024 · 2020-07

PROJECT SUMMARY The renin-angiotensin-system (RAS) plays a central role in regulating systemic blood pressure. This is illustrated by the proven benefit of RAS-targeted drugs such as angiotensin receptor blockers, which are critical to the treatment of hypertension, heart failure and kidney disease. The actions of the RAS depend on the peptide angiotensin II (ang II) acting on cells that express the G-protein coupled type 1 angiotensin receptor (human: AT1; mouse: AT1a). Our group has been at the forefront of unmasking cell-specific roles of ang II signaling within different cell populations in the kidney. These studies have revealed novel roles for ang II to act distinctly in different cell types to drive pathogenic mechanisms associated with hypertension. This suggests that the overall, systemic effect of ang II on blood pressure results from the cumulative actions of ang II on multiple cell types within the body. Our preliminary studies analyzed recently published single-cell RNA Sequencing datasets to explore the cell-specific expression of angiotensin receptors within the kidney. We find that pericytes, a mural cell type associated with capillaries and the glomerulus, express the mouse AT1a receptor. Additionally, we confirmed this by measuring AT1a expression from rapidly sorted pericytes from the kidney. However, the role of angiotensin signaling in pericytes remains under-examined. This is despite multiple lines of evidence that suggest renal pericytes play a central role in regulating blood pressure and renal injury, angiotensin-linked processes which are pathologically altered in hypertension and chronic kidney disease. This project will test the overall hypothesis that angiotensin II signaling within pericytes contributes to the development of hypertension and renal injury. This candidate has developed a novel mouse line which has inducible pericyte-specific deletion of the AT1a receptor. First, the contribution of pericyte ang II signaling to blood pressure control will be determined under baseline conditions and during ang II hypertension. Next, the effect of ang II signaling within pericytes on renal injury in the context of hypertension will be assessed. This research will be carried out by an applicant with excellent training in biomedical research with a strong publication record. The training for this proposal will occur at Oregon Health & Science University within the Division of Nephrology and Hypertension under the primary mentorship of Dr. Susan Gurley a leader in the field of cell-specific actions of RAS signaling in the kidney. This project will also be supported by two other co-mentors: Dr. Anusha Mishra, an expert on pericyte biology and microvascular blood flow, and Dr. Lynne Sakai, an expert on vascular fibrotic signaling. Career development activities include training in mouse micro-surgery, ex vivo slice imaging, assessment of renal pathology, and bioinformatic analysis of single-cell RNA sequencing datasets. This training is designed to launch the candidate to lead the next generation of kidney research with well-honed skills in animal physiology and molecular biology. This will setup the candidate to meet his long-term career coal of becoming an independent investigator focusing on the cellular and molecular causes of hypertension and renal injury.

NIH Research Projects · FY 2024 · 2020-07

PROJECT SUMMARY/ABSTRACT Upper limb reaching and grasping movements require complex cortical control circuits involving both motor- control outputs and real-time somatosensory feedback. Neurological disorders such as strokes, brain trauma, and spinal cord injury may result in a loss of the ability to perform these tasks. Many teams, including our own, are working to restore upper extremity function by using human neural signals to control the movements of a robotic limb with multiple degrees of freedom [1-3]. However, without somatosensory feedback, even the most basic limb movements are difficult to perform in a fluid and natural manner [4, 5]. There have only been a limited number of human studies exploring how to generate somatosensory feedback. Using subdural electrocorticography (ECoG) grids placed on the human primary somatosensory (S1) hand area in patients with epilepsy who require intracranial monitoring, we propose studies directed toward understanding how somatosensation is cortically encoded and how we can restore upper extremity somatosensation via electrical stimulation. To accomplish this, I have assembled a multidisciplinary mentoring team, led by Dr. Gianluca Lazzi, with an established history of success in mentoring early investigators. From my mentoring team, I plan on learning about neural modeling, study design and biostatistics, and medical device development. My long-term goal is to become an independent NIH-funded neurosurgeon-scientist who makes significant contributions to our understanding of sensorimotor integration. In Aim 1 we will use the participants own ECoG responses to real touch to guide a systematic mapping of stimulation parameter space to find distinct percepts of somatosensation. Much like how clinical neurostimulators such as deep brain stimulators (DBS) for movement disorders and vagus nerve stimulators (VNS) are therapeutic only at specific stimulation settings, we hypothesize that we will find specific stimulation combinations that result in different types of somatosensation. In Aim 2 we will compare task performance using artificial somatosensation versus native touch. In Aim 3 we will quantify how real touch and artificial somatosensation generated by ECoG stimulation differ in response time between real touch/stimulation and participant perception. These results and the mentoring provided through this K23 program will be a critical foundation for my transition to an independent investigator in sensorimotor integration.

NIH Research Projects · FY 2024 · 2020-07

Abstract The long-term goal of this study is to increase our understanding of the immune mechanisms involved in the pathogenesis of allergic diseases and asthma. Autophagy is an evolutionarily conserved and highly regulated essential homeostatic process that ensures lysosome-dependent bulk degradation of cytosolic proteins and organelles. Alterations in autophagy have been implicated in numerous conditions afflicting humans, including aging, cancer, neurodegenerative processes, and immune responses, as autophagy is essential for the generation of both innate and adaptive immune responses to pathogens. This project is motivated by recent published data from our laboratory and others, demonstrating that abrogation of autophagy, particularly in dendritic cells (DCs), induces severe airway hyperreactivity (AHR) in animal models (J Allergy Clin Immunol, 2016; Science. 2017). Moreover, several studies clearly demonstrate that genetic variants in Atg5, a critical gene in autophagy, are significantly associated with childhood asthma. In support of those studies, our preliminary results suggest that: A) treatment with autophagy inducers reduces AHR in animal models sensitized with allergens, B) enhancement of autophagy in dendritic cells induces IL-10 and significantly up- regulates PD-L2, which in turn robustly polarizes naïve T cells towards Foxp3+ regulatory T cells, C) genetic ablation of autophagy, particularly in DCs, induces steroid-resistant AHR in murine models, and D) autophagy is severely impaired in pulmonary dendritic cells obtained from patients with moderate to severe asthma. We now propose to investigate if enhancement of autophagy, particularly among antigen presenting cells, ameliorates pathology associated with asthma, suppresses unwanted lung inflammation and ultimately improves lung inflammation and function. To test this hypothesis, we first designed several approaches utilizing tissue-specific and conditional knockout murine models established in our laboratory. Second, we intend to modulate autophagy using a novel and robust autophagy inducer that was discovered recently by our collaborators at USC. Finally, we will extend our preliminary results in humans by assessing autophagy levels in the bronchoalveolar fluid and peripheral blood of patients with asthma, and determine if treatment with autophagy inducers can enhance immune-regulatory pathways. For the human studies we successfully established collaborations with UCSF pulmonary group and will utilized their lung biopsy repository samples obtained from well-defined cohorts of patients with asthma including neutrophilic asthma. Furthermore, we have assembled a team of scientists including a leading expert in autophagy and the chief of clinical pulmonology at USC to complement our laboratory's extensive experience in pre-clinical models of AHR. We believe that the results obtained from this study will provide novel insights into an important and previously unrecognized role of autophagy in asthma.

NIH Research Projects · FY 2025 · 2020-06

PROJECT SUMMARY/ABSTRACT Myocardial infarctions are caused by coronary artery occlusions that acutely deprive a localized region of myocardium of oxygenated blood, resulting in a steep oxygen gradient at the infarct border zone. Infarcted tissue then progresses through a pro-inflammatory phase of wound healing, followed by an anti-inflammatory, pro-fibrotic phase. However, for reasons that are poorly understood, the infarct border zone often undergoes adverse remodeling that does not resolve, leading to pathologies such as prolonged inflammation, fibrosis, arrhythmias, pathological hypertrophy, and heart failure. Cardiomyocytes, macrophages, and fibroblasts are each key components of the myocardium and are known to regulate each other. However, how an oxygen gradient (a defining feature of the infarct border zone) impacts crosstalk between these three cell types and downstream remodeling is poorly understood, largely due to limitations of existing model systems. During the first funding period of this R01, we engineered innovative “Myocardial Infarct on a Chip” devices that enabled us to co-culture hypoxic and normoxic cardiomyocytes and/or fibroblasts, which led to the new discovery that hypoxic-normoxic crosstalk had a detrimental effect on cardiomyocyte physiology and heightened pro- inflammatory signaling in both cell types compared to uniform normoxia and uniform hypoxia. Building on these results, our new goal is to test the hypothesis that oxygen-dependent crosstalk between cardiomyocytes, fibroblasts, and macrophages is a driving factor of pathological remodeling after myocardial infarction. To test this hypothesis, we will use devices that we developed during the first funding period to map intercellular circuits between cardiomyocytes, fibroblasts, and macrophages in non-uniform oxygen environments and quantify the molecular and functional phenotypes of each cell type. In Aim 1, we will determine the impact of hypoxic-normoxic crosstalk between cardiac fibroblasts and macrophages on functional and transcriptional phenotypes, including proliferation, phagocytosis, and migration. In Aim 2, we will determine the impact of cardiomyocyte-fibroblast-macrophage hypoxic-normoxic crosstalk on cardiac tissue functional and transcriptional phenotypes. We will measure cardiomyocyte tissue physiology (electrophysiology and contractility) and use single-cell proteomic technologies to deconvolve cell type-specific secretions and changes to the proteome. In Aim 3, we will determine the independent and combined impact of an oxygen gradient and direct contact with fibroblasts and/or macrophages on cardiomyocyte tissue phenotypes. We will establish technologies to perform spatial RNA sequencing in engineered cardiac tissues comprising cardiomyocytes, fibroblasts, and macrophages on our oxygen gradient device, which will also enable us to benchmark our transcriptomic data to published datasets of infarcted myocardium. Our project combines cutting-edge technologies in tissue engineering and molecular analyses and will lead to new discoveries that will inform novel therapeutic strategies to mitigate pathological remodeling after myocardial infarction.

NIH Research Projects · FY 2025 · 2020-06

ABSTRACT Patients with locally invasive triple negative breast cancer (TNBC) who have persistent minimal residual disease (MRD) despite neoadjuvant therapy are at significant risks of developing lethal metastasis. This represents one of the outstanding unmet needs in breast cancer therapy. A major cause of this high failure risk is the presence of rare, low- proliferative disseminated tumor cells (lpDTCs), which are highly resistant to treatment. Many lpDTCs can persist in distant organs for many years before reactivating to form metastasis. Attempts at eliminating lpDTCs in TNBC have not been successful due to their rarity, making it difficult to isolate individual lpDTCs to identify therapeutic targets. To that end, we report the identification and characterization of the IL-6, IL-6 receptor, and p38 (IL-6/R/p38) axis as a critical signaling pathway required for the maintenance of a significant majority of lpDTCs in TNBC. In cultured human TNBC cells and mouse models of TNBC, lpDTCs in the bone marrow (BM) can be forced out of quiescence simply by inhibiting IL-6/R signaling. More importantly, once acutely reactivated, lpDTCs become exquisitely sensitive to chemotherapy. Thus, the IL-6/R pathway is an attractive therapeutic target. In this proposal, we will test a novel therapeutic strategy in a Phase I and II trial in patients with TNBC by specifically inhibiting the IL-6/R pathway to force lpDTCs into proliferation, and then use conventional chemotherapy to eliminate these cells. First, we will determine whether this treatment strategy is safe in patients in a standard dose finding Phase I study of sarilumab, an IL-6R inhibiting antibody drug recently approved to treat rheumatoid arthritis, sequentially combined with capecitabine, a standard breast cancer chemotherapy drug, in patients with metastatic breast cancer (Aim 1). The Phase I’s objectives are to determine tolerability and safety of the combination and the recommended dose of the combination for the Phase II. Next, we will conduct a Phase II single-arm study using this recommended dose regimen in patients with stage I-III TNBC who have persistent MRD in breast tissue or surrounding lymph nodes after neoadjuvant therapy (Aim 2). The Phase II objectives are to determine how effective this drug combination is at clearing BM lpDTCs, and if so whether patients cleared of BM lpDTCs have a higher rate of progression-free survival at two years compared to patients historically treated with capecitabine alone. In Aim 3, we will isolate individual lpDTCs from BM aspirates collected in this trial using the conventional magnet-based enrichment method and a locally developed microfluidic device to 1) enumerate lpDTCs before and after treatment to determine the lpDTC clearing efficacy of the test drug combination; and 2) to perform genomics analysis of single lpDTCs, primary and metastatic tumor samples from the same patients. We will use a novel computational platform recently developed to analyze gene network changes in response to treatment and tumor microenvironments that breast cancer cells transition during metastasis. The goals are to 1) gain a deeper understanding of how lpDTCs are generated and maintained; and 2) yield additional targets that can be combined with the IL-6/R pathway to improve DTC-targeting strategies in the near future.

NIH Research Projects · FY 2025 · 2020-06

PROJECT SUMMARY Esophageal adenocarcinoma (EAC) is one of the deadliest malignancies, and its incidence has strikingly increased 6-8 fold in Western countries (including the United States, UK and several European countries) over the past 4 decades. Despite new insights gained from recent genomic analyses, meaningful therapeutic improvements have not occurred and the 5-year survival of EAC hasremained extremely low (~20%). Therefore, alternative research approaches, including advanced epigenomic studies, are desperately needed to understand the molecular basis of EAC for developing novel treatment regimens. Barrett’s esophagus (BE) is a premalignant condition and is considered as the obligate precursor lesion of EAC. During Barrett’s esophagus- associated neoplastic evolution, benign BE first becomes dysplastic and then progresses to EAC. Therefore, BE serves as an ideal pre-malignant model for the investigation of the step-wise neoplastic evolution of esophageal epithelial cells. However, our understanding of the molecular mechanisms promoting BEAN remains limited, with key questions (e.g., the primary drivers for the malignant transformation of BE into EAC) still unaddressed. We and others have shown that malignant transformation is accompanied by genome-wide gains and losses of enhancers and super-enhancers, which are occupied and regulated by upstream master regulator transcription factors (MRTFs). Indeed, our recent studies demonstrated profound alterations in both enhancer usage and MRTF activity between normal gastroesophageal junction (NGEJ), BE and EAC samples. Particularly, we have identified a set of EAC-specific MRTFs (ELF3, KLF5, GATA6, EHF). Pilot experiments have shown that these 4 MRTFs co-occupy hundreds of EAC- specific enhancers and super-enhancers, indicating they may regulate the EAC transcriptome. Moreover, these EAC-specific MRTFs are highly and uniquely expressed in EAC compared with normal GEJ or BE samples and are functionally required for EAC cell proliferation. Based on these findings, we hypothesize that EAC-specific MRTFs directly promote the malignant transformation of BE cells by rewiring enhancers and super-enhancers across the epigenome, activating signaling pathways and cellular processes essential for EAC development. We will test this hypothesis by investigating the biological functions of MRTFs in human BE-derived 3D organoids. In addition, we will study the mechanistic basis of the strong association between obesity and EAC by focusing on the regulatory loop of MRTF and fatty-acid synthesis, which is the key downstream pathway identified by our preliminary data. These investigations promise to establish primary driving forces of BE-associated neoplasia evolution and uncover epigenomic mechanisms underlying esophagus transformation, which will fundamentally transform our insights into the biology of esophageal cancer. More importantly, successful execution of this proposal may identify potential avenue for the prevention and early intervention of EAC by targeting fatty-acid synthesis pathway inthe high-risk individuals (e.g., refractory and/or high-grade BE patients) with obese condition.

NIH Research Projects · FY 2024 · 2020-06

PROJECT SUMMARY Candidate: Juliet Emamaullee is an Assistant Professor of Clinical Surgery at the University of Southern California (USC) and an attending liver and kidney transplant surgeon at Keck Hospital and Children’s Hospital- Los Angeles. Dr. Emamaullee has been working with her proposed K08 mentor, Dr. Omid Akbari, and her co- mentor, Dr. Shahab Asgharzadeh, to learn about mass cytometry approaches to characterize immune responses and now has begun independent work to develop these techniques to analyze the process of rejection in liver transplant (LT) recipients. The project aims to provide her with additional skills and knowledge required to achieve her long-term goal of studying the immunologic mechanisms involved in development and progression of LT rejection in order to develop new diagnostic, preventative, and therapeutic approaches to improve post-LT outcomes. Career Development Plan: Dr. Emamaullee has strategically planned to gain the necessary training and mentoring that will be required for her successful transition to being an independent investigator through select coursework and a robust mentoring plan. She has also organized an advisory committee composed not only of leaders in the field but also those able to directly impact her career advancement. The immediate training objectives are focused on consolidating her expertise in: (1) advanced immunological techniques including mass cytometry; (2) bioinformatics and data analysis; and (3) immunological pathways of rejection in clinical LT. This will not only ensure that Dr. Emamaullee's research project progresses as planned but will also ensure her progress will be recognized through promotion and obtaining independent research funding. She has an impactful, unique research project that is sufficiently different from her mentor's research to avoid competition or overlap. Research Plan: The proposed study leverages the extensive resources available at USC to address an important public health issue, which makes it directly relevant to the NIH mission. Hepatocellular carcinoma is on pace to become the leading global indication for LT, and rejection continues to be an important cause of graft loss and failure post-transplant. The diagnosis of rejection is not correlative to changes in liver blood tests and thus requires an invasive biopsy. Recently, there have been significant advances in the sensitivity of techniques to characterize immune responses, even in small tissue samples. We hypothesize that a liver-focused immune panel can be developed using imaging mass cytometry (IMC) to deeply analyze intrahepatic immune infiltrates in human liver tissue. We also hypothesize that graft-infiltrating lymphocytes can be characterized using IMC to better understand which subpopulations mediate allograft rejection in LT. First, we will develop a Liver Immunology IMC Panel using tissue obtained from LT patients with chronic rejection. Furthermore, we will utilize this assay to characterize graft-infiltrating lymphocyte subpopulations in chronic rejection and compare to results obtain using tissue obtained from LT patients with acute rejection. Immune profiles in each phase of rejection will be quantified and mapped, as well as compared to clinical parameters. Lastly, we will study LT patients prospectively to determine if these rejection-associated lymphocytes can be tracked in the blood during and after episodes of rejection. This project represents the first application of IMC in solid organ transplantation and has the potential to expand our knowledge of alloimmunity in clinical LT, which could provide the basis for a noninvasive assay of rejection in LT patients.

NIH Research Projects · FY 2024 · 2020-06

Project Summary It has been nearly 15 years since the last FDA approval for a new treatment for Alzheimer's Disease and Related Dementias (ADRD). Critical to the mission to improve the available therapies and curb the public health impact of ADRD will be a new generation of ADRD scientists, especially scientists with the unique training and skills necessary to design and perform clinical trials. This training is rarely provided through the traditional course of medical or biostatistical education. As a result, there is a dearth of well-trained ADRD clinical trialists. Moreover, there is very limited diversity among the current group of active ADRD trial investigators. To develop improved therapies for ADRD, multidisciplinary expertise in clinical trials will be necessary, including medical specialists but also expertise in biostatistics, trial design, biomarkers, ethics, and informatics. This proposal requests support to establish a first-of-its-kind training program in the essential elements of ADRD trials. The Institute on Methods and Protocols for the Advancement of Clinical Trials in ADRD (IMPACT-AD) Course will leverage the full infrastructure and expertise of the Alzheimer's Clinical Trials Consortium (ACTC) affiliated faculty. IMPACT-AD will be conducted annually to attract and train the next generation of ADRD clinical trialists, with a particular focus on improving the diversity of ADRD clinical investigators across race/ethnicity, gender, and scientific/professional backgrounds. IMPACT-AD seeks to provide a diverse range of clinicians, scientists and researchers with a modern and robust training in the design and conduct of ADRD clinical trials.

NIH Research Projects · FY 2025 · 2020-04

PROJECT SUMMARY The goal of the proposed work is to improve clinical predictions of stroke recovery and, subsequently, precision rehabilitation, by developing powerful statistical models that use routine, baseline clinical assessments (clinical MRIs, demographics, and behavior) to predict motor and cognitive stroke outcomes at 3, 6, and 12 months. This work builds on results from our current R01 grant (2020-2025) which established the role of global brain health (GBH; measured across cellular, vascular, and glymphatic domains as measured by brain age, white matter hyperintensities [WMH], and enlarged perivascular spaces [PVS], respectively) in accurately predicting stroke recovery. Specifically, using longitudinal data from baseline to 3-months post-stroke, we find that poorer GBH at baseline predicts worse lesion damage and more severe sensorimotor impairment at 3 months, and, conversely, more severe lesion damage at baseline predicts worsened GBH at 3 months. Relatedly, using a large, cross- sectional database of patients from acute to chronic stroke, we confirm that GBH is strongly associated with sensorimotor outcomes, with strongest relationships in the chronic stage, after secondary atrophy has time to evolve. We also find that GBH mediates relationships between lesion damage and stroke outcomes, suggesting that interventions to improve brain health could potentially mitigate the impact of stroke damage. However, while GBH appears to be a clinically useful biomarker, it is challenging to translate these findings into the clinic because the study of GBH requires high-resolution MRIs which are typically only acquired as part of research studies. Therefore, in this study we aim to leverage recent advances in generative AI that will allow us to extract GBH metrics from routinely acquired clinical MRIs. This study has three specific aims. Aim 1 will optimize AI algorithms to generate synthetic, high-resolution metrics (MRIAI) from routine clinical MRIs (MRIc) specifically for people with stroke, utilizing data from 437 people with stroke who have both MRIc and research MRIs (MRIR) from the ENIGMA Stroke Recovery database. Aim 2 will define longitudinal trajectories of MRIAI and their associations with impairment over the first year of stroke, with the hypothesis that declines in functional outcomes between 6 to 12 months post-stroke are correlated with worsened brain health during that same time period. For this aim, we will recruit 210 people with stroke for baseline, 3-, 6-, and 12-month clinical brain scans with brief behavioral assessments. Aim 3 will develop clinical decision trees that utilize baseline AI-enhanced clinical MRIs to predict mild, moderate, or severe impairment post-stroke, providing ranges of GBH and lesion values associated with each level of recovery. Decision tree predictive models will be validated on a separate dataset from a recently completed observational study (STRONG with baseline clinical MRIs and 3-, 6-, and 12-month outcomes (N=488) and openly shared as an easy-to-use, downloadable software toolkit. Successful completion of this work will lay the foundation for personalized treatments based on individuals' unique brain health profiles, such as targeted pharmaceuticals or lifestyle interventions, with implications beyond stroke to other age-related diseases.

NIH Research Projects · FY 2026 · 2020-03

PROJECT SUMMARY Cochlear implants (CIs) have transformed the lives of over one million people with severe-to-profound hearing loss by restoring access to speech. However, substantial challenges remain in domains essential for real-world communication: pitch perception, spatial hearing, and speech recognition in noisy and reverberant environments. These limitations stem largely from conventional processing strategies like the Advanced Combination Encoder (ACE), which prioritize spectral energy while discarding fine temporal structure and lacking synchronization across ears. Consequently, CI users often struggle to enjoy music, detect voice pitch, localize sounds, and understand speech in complex auditory scenes. This project targets three major innovations to overcome these deficits: (1) precise stimulation timing, such as peak-derived timing strategies that synchronize electrical stimulation with peaks in the acoustic waveform to better preserve temporal detail, (2) bilateral synchronization, which coordinates stimulation timing across ears to restore spatial hearing cues critical for localization and segregation, and (3) a lab-developed, biologically inspired adaptive noise reduction algorithm, Binaural Fennec, which suppresses background noise while preserving binaural timing and level cues. Three Specific Aims structure this work. Aim 1 examines whether peak-derived timing enhances pitch perception and voice pitch understanding, reinforced through structured auditory training. Aim 2 evaluates whether synchronized bilateral stimulation improves localization accuracy and spatial release from masking in both real and virtual acoustic environments. Aim 3 compares synchronized stimulation with commercial and research-grade suppression strategies across a range of masking and reverberation conditions using ecologically valid comprehension and source-tracking tasks. By combining individualized stimulation maps, cue-specific psychophysics, and real-world outcome measures, this study provides a rigorous framework for advancing cochlear implant processing. Findings will inform future programming strategies, optimize user outcomes, and guide the next generation of auditory prosthetics aimed at restoring naturalistic hearing.

NIH Research Projects · FY 2025 · 2020-02

PROJECT SUMMARY/ABSTRACT The overall goal of this proposed renewal is to establish that the focal region of low shear stress (0-4 dyne/cm2) immediately downstream or in the post-stenotic segment of intracranial atherosclerotic disease (ICAD) is a marker of atherogenesis and recurrent stroke, providing a therapeutic target for anti-inflammatory or anti- thrombotic interventions. Our central hypothesis is that post-stenotic low shear stress associated with atherogenic endothelial pathophysiology provides a rational basis for precision medicine of ICAD. Our prior data on low shear stress in the MCA in SAMMPRIS confirms the potential influential role of shear stress associated with endothelial pathophysiology recognized in systemic atherosclerosis yet extended to the cerebral circulation for the first time. Our three expanded independent specific aims leverage an ongoing, invaluable collaboration and the unmatched quality of the SAMMPRIS imaging archive. The Neurovascular Imaging Research Core at UCLA will conduct the prospective experiments to validate focal low shear stress measured on CTA CFD of ICAD across all arteries in SAMMPRIS with detailed anatomical flow models created from the same source images [SA-1]. This aim enables us to use our validated flow models to directly observe flow vortices and adjacent low shear stress in all ICAD arterial sites [SA-1]. These validated flow models serve as a scaffold for endothelium, where the cell morphology, expression of VCAM-1 and platelet aggregation can be studied in all ICAD locations [SA-2]. The clinical relevance of post-stenotic low shear stress (0-4 dyne/cm2) in these arterial lesions will be corroborated by imaging adjudication of stroke in the downstream territory after initial treatment in SAMMPRIS [SA-3]. Associations of this clearly defined potential therapeutic target of post-stenotic low shear stress will be examined with respect to all arterial sites and treatment methods in SAMMPRIS [SA-3]. All image post-processing, CTA and DSA CFD, 3D printing, and biological assays of endothelial pathophysiology will be conducted at UCLA, where we have pioneered this workflow. The ongoing multidisciplinary enthusiasm of SAMMPRIS trial leadership is an important element of this new approach to ICAD that employs our collaborative work and publications of these landmark trials and their detailed imaging and clinical analyses. Our extensive prior work reflecting collaborative multidisciplinary expertise on a novel imaging and biological framework, coupled with intensive experience linking the SAMMPRIS imaging and clinical datasets, provide a logical extension of knowledge on atherogenic low shear stress into the cerebral circulation.

NIH Research Projects · FY 2026 · 2019-09

Project Summary Consumption of an obesity-promoting “Western diet” (WD) is strongly associated with cognitive impairment and dementia risk, even independent of obesity 1-5. The hippocampus (HPC), a brain region classically associated with memory function and more recently with energy balance, is particularly vulnerable to the negative effects of WD consumption 4, 6. Emerging evidence from both humans and rodent models identifies the juvenile and adolescent stages as especially vulnerable developmental periods for WD-induced HPC dysfunction 5, 7-9. Our preliminary results presented herein reveal that juvenile and adolescent WD consumption is associated with long-lasting memory impairments and hyperphagia during adulthood. Remarkedly, these negative outcomes are present in the absence of obesity and persist despite a healthy diet intervention beginning at adult onset. This proposal will discover the biological mechanisms mediating early life WD-induced programming of disordered memory performance and eating behavior during adulthood. We recently discovered a functional link between early life sugar consumption, the gut microbiome, and HPC dysfunction 10. Applying an analogous approach with our novel early life WD model (sugar + saturated fat + processed foods), we have identified substantial gut microbiome changes in early life WD-fed vs. control rats, including alterations in bacterial populations that are correlated with HPC-dependent memory performance. The functional relevance of these results will be mechanistically evaluated in this proposal. Given that WD- induced microbiome changes are associated with changes in brain acetylcholine (ACh) signaling 11, and that HPC ACh signaling promotes memory function 12-18, additional experiments will explore our novel hypothesis that aberrant HPC ACh signaling is a neural basis for WD-associated HPC dysfunction. This hypothesis is supported by our preliminary results showing that early life WD yields long-lasting reductions in markers of ACh tone, and that nonspecific cholinergic receptor agonism reverses early life WD-associated HPC-dependent memory impairments. Proposed experiments utilize state-of-the-art in vivo imaging and pharmacological approaches to identify mechanisms linking early life WD consumption, HPC dysfunction, and ACh signaling. In addition to regulating memory function, the HPC has emerged as a key brain region in the higher- order control of food intake 6, 19. Our preliminary results show that early life WD consumption yields increased caloric intake driven by elevated meal size, an effect that persists even after a healthy diet intervention. Additional preliminary data reveal that HPC ACh binding dynamically increases throughout the course of a meal, and this effect is highly predictive of meal size. We will expand these results by evaluating how early life WD influences dynamic HPC ACh binding during meal consumption and sensitivity to various physiological satiation signals. Collective results from the proposal will identify novel neurobiological mechanisms through which the early life dietary environment programs for impaired cognition and altered energetic outcomes.

NIH Research Projects · FY 2024 · 2019-09

! PROJECT SUMMARY In 2015, evidence that e-cigarette use (“vaping”) in adolescents and young adults (AYAs) had increased and was associated with increased risk of cigarette smoking initiation generated concern in the public health community. Subsequent research has left the field with several critical questions, including: (1) whether vaping truly has a causal effect on smoking or merely reflects a common liability toward deviancy among ‘high-risk’ AYAs with emotional or behavioral problems, (2) whether an emerging wave of new vaping products, including new nicotine products such as JUUL, and an increasingly diverse class of products dedicated to vaping cannabis plant, oils, and waxes, may increase the appeal and addictive potential of vaping, and (3) whether there exist particular characteristics of vaping products and biopsychosocial mechanisms that underlie the risk of AYA vaping initiation, progression, and transition to other forms of drug use that could be targeted in prevention efforts. The uncertainties regarding the impact of AYA vaping have left policy officials with little evidence to determine if AYA vaping should be prioritized in public health programs, and if so, the most effective strategies for prevention. To address the evidence needs and provide a flexible framework for future study of the impact of various vaping products on the AYA tobacco product and cannabis use burden, we will test a novel ‘catalyst model’ of AYA vaping. The catalyst model proposes two steps, which we will evaluate in Aims 1 and 2 of this proposal. Step 1 (AIM 1). To determine whether (a) AYAs with fewer emotional-behavioral risk factors who have been previously deterred from drug use in traditional (non-vaporized) forms are at risk of vaping initiation, (b) the unique qualities and product features of vaping (e.g., concealability, flavors, appealing technology, social acceptability, low perceived harm) increase risk of AYA vaping, and (c) features of vaping products disproportionately increase the risk of vaping initiation for low-risk AYAs. Step 2 (AIM 2). To determine whether (a) vaping increases the risk of cross-product transitions involving initiation of other vaping products, or combustible nicotine or cannabis, as well as increases risk of progression to problematic drug use outcomes, including dependence, poly-drug use, and chronic drug use through early adulthood, (b) rewarding effects from exposure to nicotine, cannabinoids, and other product components (e.g. flavorings) increases risk of cross-product transitions and problematic drug use outcomes, and (c) product characteristics modify this association. To test the model, we will leverage data collected from participants from age 14-19 (2013-2018) from our existing cohort and follow participants into early adulthood (20-23, from 2019-2023; N~2000). We will also recruit a new cohort of 9th grade students at age 14 (N=2500) at the same schools as part of a cohort-sequential design that will apply causal inference analytic approaches to determine whether observed associations are likely causal. Collectively, this project will provide critical information regarding the priority and potential targets of public health efforts aimed at reducing the potential adverse public health effects resulting from AYA vaping, including tobacco-related cancer.

NIH Research Projects · FY 2024 · 2019-09

PROJECT SUMMARY/ABSTRACT The discovery that individuals with Trisomy 21, or Down syndrome (DS) have neuropathological features identical to those with sporadic Alzheimer's disease (AD) played a critical role in the identification of the amyloid precursor protein gene on chromosome 21 supporting the amyloid cascade hypothesis. People with DS have a lifetime risk for dementia in excess of 75% and comprise the world's largest population of genetically-determined AD. Just as studying DS helped identify the role of amyloid precursor protein mutations in AD pathogenesis, it is also likely to inform us of the potential benefit of manipulating the amyloid pathway on treatment outcomes in AD. It is critically important to the DS population and to the AD therapeutics field to conduct clinical trials, particularly those targeting amyloid accumulation, in individuals with DS. With this application, we propose to utilize the existing depth and breadth of expertise of the NIA-funded Alzheimer's Clinical Trial Consortium (ACTC) to conduct AD clinical trials in adults with DS across performance sites with expertise in DS including the Alzheimer's Biomarker Consortium for Down Syndrome (ABC-DS). As part of an NIH award received last year, we established the ACTC-DS network which includes working groups comprised of leaders from ACTC, ABC-DS and the European Horizon21 DS network to develop the collaborations, infrastructure and plans required to conduct AD clinical trials in DS. During the proposed R61 `Trial Readiness Phase' of the present project, in Aim 1, we will enroll 120 adults with DS (ages 35-55) across 15 sites into a trial ready cohort (TRC) to collect outcome measures and biomarkers harmonized with those being collected in the ongoing ABC- DS study (n = ~400). In Aim 2, we will determine the relationships between cognitive measures and AD biomarkers to identify endpoints for clinical trials that best reflect disease progression. During the R33 `Clinical Trial' phase, for Aim 3, we propose to implement a phase II randomized, double-blind, placebo-controlled trial to evaluate the safety and tolerability of a promising anti-amyloid therapeutic among individuals the TRC. In Aim 4, we will determine the impact of this agent on biomarker evidence of disease modification. Fundamentally, this project will serve to bring AD therapies to the DS population by leveraging the infrastructure of ACTC and incorporating the experience and expertise of the ABC-DS and Horizon21 networks. Beyond the proposed trial, this will establish the means and methods to conduct future therapeutic trials in this population. The potential impact of this approach on improving the lives of adults with DS as well as the general population cannot be overstated.

NIH Research Projects · FY 2025 · 2019-09

Glomerular endothelial cells (GEnC) play pivotal roles in the maintenance and function of the glomerular filtration barrier (GFB), and endothelial injury is a primary event in the development of chronic kidney disease (CKD). Several systemic and local secreted factors derived from podocytes and mesangial cells including insulin-like growth factor (IGF) and vascular endothelial growth factor (VEGF) have been established to help maintain the specialized GEnCs and the GFB. In the previous grant cycle our group discovered a key, but formerly overlooked, regulatory role of macula densa (MD) cells in glomerular endothelial function in health and disease. Unexpectedly, the roles include the secretion of novel MD-specific angiogenic, tissue growth, patterning, and extracellular matrix (ECM) remodeling factors and their paracrine mechanistic actions to control resident progenitor cells and regulate endogenous kidney tissue remodeling and regeneration. This renewal proposal aims to extend the novel, paradigm-shifting concept of glomerular endothelial regulation by the MD. We focus on the #1 top enriched MD-specific factor - pregnancy-associated plasma protein A2 (Pappa2), as the most proximal and principal GEnC regulating cellular and molecular pathway. Specifically, we hypothesize that MD- derived secreted Pappa2 and cell communication network (CCN1) are key determinants in the maintenance of a healthy glomerular endothelium and GFB by acting as central physiological regulators of IGF1-VEGF signaling efficiency in GEnCs. Preliminary work identified MD and GEnC-specific high expression and functional activity as well as angiogenic effects of the complementary enzyme/ligand/receptor pairs of MD Pappa2/CCN1 and GEnC Igf1r/Vegfr2/Itg/ECM signaling axis in mouse, rat, and human kidney. Single-cell genetic cell fate tracking with serial intravital multiphoton microscopy (MPM) confirmed clonal GEnC remodeling by endothelial precursor cells localized in the glomerular arterioles closest to the MD. Pappa2 knockout or Vegfr2 blockade resulted in endothelial injury, GFB dysfunction, glomerulosclerosis (GS), albumin leakage, all improved with CCN1 treatment. This project will use a comprehensive experimental approach that includes GEnC and MD cell cultures in vitro, new transgenic Cdh5-Confetti BalbC mouse and Pappa2 knockout rat models with both males/females in consideration of expected sex-specificity. Genetic single-cell fate tracking, disease models, serial MPM, and AAV9-mediated MD-specific gene delivery in vivo will investigate and therapeutically translate the key endothelial regulatory functions of MD-derived Pappa2. The specific aims are to (i) Examine the functional importance of maintaining the MD Pappa2-CCN1 balance for normal function of the glomerular endothelium in physiological conditions, (ii) Determine the disease modifying role of the MD Pappa2-CCN1 balance in endothelial injury, (iii) Test the therapeutic potential of MD-targeting Pappa2/CCN1 gene therapy in vivo for CKD.

NIH Research Projects · FY 2024 · 2019-09

ABSTRACT Our revised proposal launches the India ENIGMA Initiative for Global Aging & Mental Health - a globally coordinated study of brain aging and Alzheimer's disease (AD), created response to the NIH FOA: Global Brain and Nervous System Disorders Research Across the Lifespan (R01; PAR-18-834; https://grants.nih.gov/grants/guide/pa-files/PAR-18-835.html). Our overall goal is to identify predictive markers in the blood, genome, and epigenome that influence brain aging in India, to better understand prognosis, and to support personalized risk evaluations on each continent. We plan to identify etiological pathways to resilience using the rich biobanking strategy developed by our partners at NIMHANS in India. To do this, we will leverage our global consortium, ENIGMA (http://enigma.ini.usc.edu), to partner with dementia research pioneers in India, creating new links between international biobanks, and building research capacity. By 2020, 70% of the world's population over age 60 will live in developing countries, with 14% in India (Mathuranath 2012). Recently, attention has been drawn to a “diversity” crisis in brain research, as most brain research is conducted in Caucasian populations from relatively wealthy backgrounds (LeWinn 2017). This lack of ethnic diversity means that: (1) we do not know if predictors of health (and disease) generalize to other ethnic groups, and (2) we fail to collect vital data that could teach us how AD progresses in populations with different genetic and environmental backgrounds. Our coordinated analyses in US/EU and Indian biobanks will help identify brain aging predictors specific to India and those that are universal. Specifically, we will: Aim 1. Create Lifespan Charts of brain aging Trajectories in India using MRI, DWI and Resting State Functional MRI. Aim 2. Identify Blood and Epigenetic Markers that Predict Brain Aging and AD in India. Aim 3. Using a combination of multimodal imaging, blood markers, and clinical data to predict clinical decline in India. We test structural equation models that hypothesize how brain aging depends on lifestyle and psychosocial factors (diet, family support, drug abuse, literacy, sleep, and depression), as well as sex, education, and AD genetic risk. With novel machine learning methods, will analyze blood markers and plasma proteomic analytes, to define processes that are harmful to brain aging. In Capacity Building Aims, we will leverage ENIGMA's successful strategies to train emerging and established scientists in India to analyze their data with high quality control and precision, with targeted biostatistical and imaging workshops to bolster capacity. This collaborative India-US initiative will enable future science initiatives, and equip the NIMHANS team with the necessary tools to train new scientists and independently conduct high impact research bridging efforts into numerous international partnerships.

NIH Research Projects · FY 2025 · 2019-09

Project Summary The proposed study will investigate endothelial progenitor cells (EPCs) taken from blood samples from older adults at risk for dementia due to aging, genetics, Alzheimer’s disease pathophysiological changes and/or cerebral small vessel disease. Extensive studies have focused on brain and cognitive markers of resilience to Alzheimer’s disease, but far fewer studies have focused on the role of potentially protective vascular factors such as EPCs. Proposed studies will utilize blood markers of EPCs and will culture EPCs from older adult blood samples to investigate whether EPCs may predict whether someone remains cognitively normal despite the presence of Alzheimer’s and vascular brain changes or whether they begin to decline cognitively. Studies will also investigate whether EPC levels predict cerebrovascular changes, including deficits in the integrity of the blood-brain barrier. Finally, EPCs cultured from older adults with and without Alzheimer’s or vascular brain pathological changes will be studied and compared in their ability to grow, function and form a blood-brain barrier in a chip-based vascular microbrain model that mimics the cerebral microvasculature in vitro. Findings from in vitro EPC studies will then be compared with findings from brain imaging measures of cerebrovascular function and blood-brain barrier integrity.