University Of California-Irvine

NIH Research Projects · FY 2025 · 2023-08

ABSTRACT In India, cervical cancer (CC) remains one of the most common malignancies among women, with about 100,000 women diagnosed annually. HIV promotes the progression of precancerous lesions. Among women living with HIV/AIDS, a lack of Human Papilloma Virus (HPV) screening, coupled with high levels of depressive symptoms and stigma, along with malnutrition, negatively impact the activation and proliferation of immune cells, further promoting development of precancerous lesions in the cervix. Programs for women living with HIV (WLH) that include HPV screening and psychosocial and nutritional support are almost non-existent, and the gap is critical in hopes of reducing high CC incidence rates. In our recently completed R01 study of 600 WLH in rural India, we assessed the impact of our “ASHA-Nutrition” intervention, co-delivered by our community health workers (ASHA), and led by nurses, in providing emotional support, skill-building, nutrition education, and/or protein-enriched food supplements. Our findings revealed that the nurse-led ASHA support plus protein supplements and nutritional education showed a significant association with improved CD4+ T cell counts and increased lean mass at 18 months as well as improved depression, social support and stigma. CC screening of 598 of these WLH revealed 13% had abnormal cervical lesions and 4 (1%) had squamous CC. Further, our preliminary data suggest that nutritional supplements may be associated with a 40% reduction in the risk of abnormal cervical lesions. Our stellar team plans to build upon our prior successful model to refine our newly developed nurse-led, ASHA co-delivered, nutrition-enhanced, ASHA-Health HPV intervention, adapted to the needs of a high-risk sub-population of women co-infected with HPV and HIV (W-Co-V), and randomized by village clusters among women treated in antiretroviral treatment (ART) centers in underserved Karnataka, India. With a major focus on secondary prevention of CC, we hope to mitigate the link between high-risk human papillomavirus (HR-HPV) persistence (measured as 2 positive tests for the same HR-HPV type, separated by 12 -18 months), risk of CC, as well as improved health of W-Co-V. We will conduct a parallel-group cluster randomized clinical trial, assessing the efficacy of our refined comprehensive, ASHA-Health HPV intervention, as it relates to CC prevention, ongoing engagement in the HIV treatment cascade, and managing nutritional health among 420 high-risk co-infected women, as compared with an enhanced Standard of Care (SOC+). Our Primary outcome is HR-HPV persistence. Secondary outcomes will be the improvement in: 1) HIV indices (HIV viral load and CD4+ T cells); 2) Nutritional indices (serum albumin levels, Vitamin A, Vitamin D, and Iron); 3) Mental health (depression and HPV/HIV internalized stigma); and 4) Engagement in care (HPV/HIV appointment keeping and ART adherence); all measures will be assessed at baseline, and at 6-, 12-, and 18- month follow-ups. The ASHA-Health HPV Intervention builds on a highly successful multifaceted US-Indo collaboration of over 10 years, has a high potential for scale-up in India, and engages HPV co-infected WLH in reducing the risk of CC as well as improving their health. The success of this intervention can lead to policy development and future implementation science trials in the prevention of CC among co-infected Indian women.

NIH Research Projects · FY 2024 · 2023-08

SUMMARY Early-life adversity (ELA) is associated with vulnerability to mental illnesses that involve disruption of the brain’s reward circuits. These vulnerabilities may manifest as anhedonia, a reduction in reward desire or pleasure that is core feature of major depression. However, whether the association of ELA with anhedonia is causal is difficult to establish in humans, and mechanisms underlying this relationship are not understood. Our well-characterized rodent ELA model reliably leads to reward-circuit disruptions in a sex-dependent manner, yet the circuit nodes and pathways that are most affected remain unclear. In searching for ELA-sensitive reward-circuit components, we discovered and are characterizing a novel projection from basolateral amygdala (BLA) to nucleus accumbens (NAc) that expresses the neuropeptide corticotropin releasing hormone (CRH). Neurons expressing CRH are often stress-sensitive, and our preliminary data suggest this is also the case for the novel CRH+BLA-NAc pathway. Building on these robust data, we will determine the functional roles of the projection in mice and test the hypothesis that ELA- induced plasticity in this pathway contributes to sex-dependent effects of ELA on reward pursuit and consumption, significantly advancing our understanding of the origins of mental illness. Aim 1 will test the hypothesis that the novel CRH+BLA-NAc pathway modulates reward pursuit (motivation) and / or consumption in typically reared male and female mice, capitalizing on the temporal resolution of optogenetics and on formal motivation tasks to probe the specific role of the projection in the motivational vs. consummatory aspects of reward. Aim 2 will use the same technologies to determine the role of the CRH+ BLA-NAc projection in aberrant, sex-specific reward behaviors resulting from ELA. Aim 3 will examine the molecular and cellular mechanisms by which aberrant CRH+ BLA-NAc inputs regulate reward behaviors: we will identify the target cells of the projection following ex vivo optogenetic activation of BLA- origin projection fibers in the NAc, and determine the relative roles of GABA neurotransmission vs CRH receptor activation in the effects of projection stimulation on reward behaviors in male and female mice.

NIH Research Projects · FY 2025 · 2023-08

Project Summary Human induced pluripotent stem cells (iPSCs) are unique in that they retain their ability to indefinitely self-renew while maintaining the capacity to self-organize and differentiate into both embryonic and extraembryonic lineages. iPSCs have emerged as a powerful tool to study human development, and disease, and have been integrated with tissue engineering approaches for regenerative medicine applications. To fulfill the promise of iPSC clinical utility, further investigation of the role of the stem cell niche in iPSC morphogenesis, lineage specification, and functional maturation is needed. While organoid approaches have revolutionized our ability to mimic organ-level function in a dish, they typically are comprised of cells from a single germ layer, missing critical cues shared by surrounding populations including the microvasculature and stroma. In addition, organoids are generated in ill-defined matrices such as Matrigel, which suffers from batch-to-batch variation, and limited tunability. To this end, we propose using micropatterned induced gastrulation models to better understand how paracrine and mechanical cues guide primitive stem cell fate. In addition, by leveraging assembloid technologies, synthetic extracellular matrix mimics, and dynamic microfluidic culture, we aim to better understand multi-germ layer interactions during tissue specification. Finally, we propose that improved iPSC derivatives can be used to better understand patient-specific differences in metabolic disorders. Collectively, we propose that using an integrative approach will permit iPSCs to be a powerful testbed for studying developmental biology and disease processes.

NIH Research Projects · FY 2026 · 2023-07

Substance use disorders (SUDs) have substantial healthcare and economic costs as well as accidental deaths from drug overdose. Adolescence is a critical period in which exposure to alcohol and other drugs markedly increases the risk for SUD. Early-life adversity (ELA), including interpersonal trauma and loss, family dysfunction and poverty, is highly prevalent and a well-established risk factor for SUD. Individuals with ELA have an earlier age of onset for the initiation and transition to SUD, greater severity and a more pernicious course, marked by a greater risk for relapse and poor treatment response, compared to counterparts without ELA. The neuroimmune network hypothesis postulates that ELA sensitizes the brain circuits involved in threat and reward processing via inflammation, initiating positive feedback loops between these systems. Also, inflammatory mediators engage these neural circuits, predisposing individuals to emotional dysregulation, and “self-medicating” behaviors, such as smoking and drug use. Such self-medicating behaviors in adolescence, a period of high neuronal plasticity, can exacerbate the neurotoxic effects of ELA, with a quicker transition from use to disorder. To our knowledge, this theory has not been tested empirically. Adolescent studies characterizing inflammatory processes in relation to ELA focused on non-specific systemic markers of inflammation which may lack sensitivity in young, healthy persons to detect the early signs of pathogenesis, and the mechanistic specificity to inform modifiable pathways, by which health disparities emerge during this developmental period. The proposed investigation addresses these theoretical and methodological issues in the following ways: (1) we will recruit adolescents, stratified based on ELA and oversampling the high-ELA group, without a prior history of substance misuse or SUD, to examine the probability of SUD onset over a 24-month prospective follow-up; (2) examine whether an inflammatory index comprising of vertically integrated measures (namely upregulated proinflammatory and reciprocal downregulated antiviral type 1 interferon genes, diminished intracellular glucocorticoid receptor signaling, increased circulating cytokines, and c-reactive protein) accounts for, partly, the association between ELA and SUD onset; (3) assess whether ELA interacts with certain clinical, biobehavioral and family-contextual factors in predicting vulnerability to, or protection against, SUD; and (4) explore whether SUD onset has a modulating influence on psychiatric, biobehavioral and family-contextual factors. By identifying the biobehavioral risk and protective factors during a critical developmental period, the study findings may help shift ELA research toward prevention and resilience and identify novel biobehavioral targets for clinical trials. The identified biobehavioral targets may elucidate for whom the intervention programs engage the underlying psychobiological processes that precede the emergence of behavioral symptoms and determine their role in the pathogenesis of SUD in this high-risk group. Ultimately, such knowledge can enhance precision care in mitigating SUD risk in ELA-exposed youth and allowing them to reach their full potential as adults and reducing the socioeconomic burden associated with early-onset SUD.

NIH Research Projects · FY 2025 · 2023-07

Project Summary Gaining genetic access to specific cell types in rodents, non-human primates and other vertebrate species is critical for enabling targeted circuit manipulations to understand normal brain function and brain. The use of gene regulatory elements for targeted gene expression is transforming brain circuitry studies. In response to RFA-MH-21-180, the Center for Neural Circuit Mapping (CNCM) team led by Dr. Xiangmin Xu at the Minority Serving Institution (MSI)-designated institution, University of California, Irvine (UCI) will collaborate with Dr. Gordon Fishell’s team at Harvard University and the Broad Institute to produce and distribute reagents developed by their Armamentarium project, “Systematic identification of enhancers to target the breadth of excitatory and inhibitory neuronal cell types in the cerebral cortex” (U01MH13070, pending award). Dr. Fishell’s team has established a novel high-throughput enhancer screening platform using gene regulatory elements that enables cell type-restricted gene expression in cortical GABAergic interneuron and pyramidal excitatory neuron subtypes at an unprecedented resolution. This is achieved using adeno-associated virus (AAV) vectors for the effective screening and validation of enhancers for specific neuron types in the mouse, non-human primate, and human brain. The first goal of our proposed research is to establish close collaborations between the UCI and Harvard University/Broad Institute teams to scale up and optimize the production of cell-type-specific enhancer-AAVs. Using our growing Center platform, the UCI team will distribute these viral reagents to qualified investigators in the neuroscience community for cell-type-specific access and manipulation. The second goal of our research is to enhance the impact of this project by engaging scientists and students from diverse backgrounds and less research-intensive institutions that serve minority communities. In Aim 1, the UCI team will form a partnership with Dr. Fishell’s team to expand seed enhancer-AAV reagents characterized by Dr. Fishell’s team to make a broad set of tools for cell-type-specific neural circuit studies across vertebrate species. We will leverage our CNCM existing expertise in neurotropic virus production and distribution to make new helper AAVs based on Dr. Fishell’s enhancers to improve the precision of genetically targeted specific circuit mapping in the CNS. In Aims 2 and 3, we will coordinate with Dr. Fishell’s pilot U01 project investigators to scale up our UCI CNCM viral production pipeline and improve our distribution platform to support viral reagent production, validation, and ample supplies for research community distribution. We will expand our recruitment of team members from diverse backgrounds facilitated by partnering with Western University of Health Sciences and Morehouse School of Medicine to include faculty, staff and students of underrepresented minorities for the proposed research. We will fulfill the RFA requirement to generate and distribute authenticated viral reagents in a well-regulated manner to be widely used in the research community. This U24 award will provide critical support for the BRAIN-Initiative Armamentarium project.

NIH Research Projects · FY 2026 · 2023-07

Abstract Overview: MDRO Carriage, Transmission, Sequelae, and Prevention in Nursing Homes This P01 Program proposal will address critically important questions surrounding the expanding problem of multidrug-resistant organisms (MDROs) in nursing homes (NH). Of the 1.4 million residents residing annually in 15,000 U.S. NHs, more than half (65%) are estimated to harbor MDROs. These MDROs not only impact medically vulnerable residents in NHs, but they can spread to surrounding hospitals and long-term care facilities, causing significant morbidity and mortality. Despite growing evidence that NHs are major reservoirs of MDROs, investments to address MDROs in this health sector are lacking. Little is known about sources or drivers of MDRO transmission, and identification of effective interventions is needed. This program integrates expertise in infectious diseases, epidemiology, microbiology, pathogen genomics, human microbiome, statistics, systems science, health economics, and agent-based models to conduct an unprecedented set of studies on five MDROs in NHs – methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococcus (VRE), extended-spectrum beta-lactamase producers (ESBLs), carbapenem-resistant Enterobacterales (CRE) and the newly-emerged resistant fungus, Candida auris. By leveraging previous and newly-conducted studies, this program will provide one of the largest compilations of MDRO isolates from NH residents and environmental fomites. A total of 16,000 MDRO isolates and 3,000 metagenomic samples from 50 NHs will be studied using epidemiology, genomics, and simulation modeling as distinct and synergistic vantage points to elucidate 1) best sampling methods for MDRO carriage and co- carriage, 2) key sources and drivers of MDRO transmission, 3) major risk factors associated with carriage, infection, and hospitalization, and 4) high-yield interventions to inform infection prevention policies to mitigate adverse health outcomes due to MDROs in NHs.

NIH Research Projects · FY 2025 · 2023-07

PROJECT SUMMARY The tumor suppressor protein p53 is the most frequently mutated protein in human cancers. About 600,000 new cancer patients in the United States are diagnosed each year with tumors expressing mutated p53. Most of the mutations are missense mutations that affect one of six hotspot sites in the p53 DNA binding domain. These cancers express full length p53 that has lost tumor suppressor activity, but has acquired gain-of-function oncomorphic properties that provide selective advantage to cancer cells. The large number of affected cancers make p53 an exquisite target for cancer therapy. However, therapeutic approaches require reactivation of mutated p53. Developing “reactivation or corrector drugs” is challenging in itself, but further complicated by very limited experience in pharma, biotech, and academia in this domain. These challenges in exploring novel therapeutic approaches by developing p53 corrector drugs have led to very slow, and limited success in clinical trials with proposed p53 reactivator compounds. It recently emerged that several of the reported compounds are likely not acting on mutant p53 in vivo, but rather exploit redox- sensitivity of cells expressing p53 mutants. Development of bona fide p53 mutant corrector drugs that bind p53 and restore a wild-type like conformation/activity in p53 cancer mutants, thus remains a central goal with potentially very high impact. To achieve this goal mechanistic understanding of the p53 cancer mutant reactivation process is essential, but currently mostly lacking due to the lack of genuine p53 corrector molecules with the exception of compounds developed specifically for the relatively rare p53-Y220C allele. We have extensively studied genetic and pharmacological p53 reactivation. We found that Intragenic rescue mutations and small molecules we are developing induce a similar conformational change and stabilize an active conformation of p53 hotspot mutants. Although reactivation mutations have no direct therapeutic potential, they help in our understanding of p53 mutant reactivation mechanisms and can guide corrector drug development. Using information obtained from reactivating second-site mutations, we have developed tool compounds that bind mutant p53 and thereby restore DNA binding activity of mutant p53 in a reconstituted purified in vitro system. p53 target genes are induced when cells harboring p53 hotspot mutants are exposed to these compounds. Furthermore, cell proliferation is halted and apoptosis is induced in a p53 mutant dependent manner. Importantly, growth of tumors carrying p53 mutants is blocked by this compound series in animal models. Tumors lacking p53 or expressing wild-type p53 are not affected by such treatment. These compounds provide strong support for feasibility to develop drug-like molecules that act as genuine p53 mutant correctors. We now propose to use these tool compounds as well as well-characterized rescue mutations to develop detailed molecular understanding of the reactivation process for p53 hotspot mutants. Findings from these studies will be essential to jump start the development of chemically diverse p53 corrector drugs.

NIH Research Projects · FY 2025 · 2023-07

Project Abstract This application is responsive to the call for “Administrative Supplements on Long-term Cancer Survivorship" and focuses on long-term young adult survivors of testicular cancer. Testicular cancer is the most common malignancy among young adult males. While survival rates exceed 95%, long-term survivors are at risk for persistent psychological distress, occupational disruption, cognitive concerns, and diminished quality of life. These late effects are especially concerning among those diagnosed in young adulthood—a developmental period marked by goal pursuits, identity formation, and career establishment. However, few studies have examined the self-regulatory mechanisms that may sustain resilience or contribute to risk across long-term survivorship. Our team is currently testing Goal-focused Emotion-Regulation Therapy (GET) in recently treated young adult testicular cancer survivors (parent award: R01CA276143). GET targets goal navigation and emotion regulation—two transdiagnostic skills central to adaptation. Preliminary data suggest GET improves psychological outcomes and stress biology in early survivorship. Yet, it remains unknown whether these core mechanisms remain relevant years after diagnosis. The objective of this cross-sectional supplemental study is to evaluate the biopsychosocial and occupational correlates of self-regulation in 100 long-term young adult testicular cancer survivors (≥5 years post-diagnosis, diagnosed at ages 18–39). We will 1) Characterize biopsychosocial and occupational burden (e.g., mood symptoms, cognitive concerns, fatigue, financial toxicity), alongside GET-targeted mechanisms (goal navigation, emotion regulation, personal agency); 2) Test associations between goal navigation and psychosocial, occupational, and biological outcomes. We hypothesize that stronger goal navigation relates to lower distress, better quality of life, and higher agency.; and 3) Examine emotion regulation in relation to these same outcomes. We anticipate that adaptive emotion regulation will be associated with more favorable functioning across all domains. Findings will clarify whether self-regulatory capacities remain operative in long-term survivorship, informing intervention adaptation, survivorship guidelines, and future longitudinal models of resilience in AYA cancer survivors.

NIH Research Projects · FY 2024 · 2023-07

Project Summary Virtually all optical microscopes for biological imaging are based on refractive objective lenses. The performance of these lenses approaches the theoretical limit, however, their use is limited to the visible to near-infrared spectral range. Even within this range, their performance is only guaranteed over a relatively narrow range, and broadband use is invariably affected by chromatic aberrations. Another problem is the group delay dispersion that these lenses introduce to short optical pulses, which reduces the efficiency of nonlinear optical (NLO) signal generation in the microscope. Taken together, these shortcomings seriously compromise the imaging properties of several NLO imaging modalities such as three-photon excited fluorescence and third-harmonic generation. In addition, refractive objectives simply cannot be used for NLO techniques that incorporate excitation light in the mid-infrared (MIR) range, such as photothermal imaging and sum-frequency generation, promising technologies based on MIR molecular contrast. The only viable alternative is the all-reflective Schwarzschild-Cassegrain (SC) objective, which is inherently achromatic but suffers from a non-ideal pointspread function and a center obscuration that limits throughput. Because of these limitations, SC lenses have not found widespread use in biological imaging applications. This lack of performance is also the reason why advances in exciting new MIR-based NLO imaging technologies have been stifled: there simply are no high-performance high numerical focusing options available to support these emerging imaging technologies. In this project, we develop a novel all-reflective high numerical aperture lens that overcomes all limitations of the SC focusing lens. Based on a non-concentric design, this new design features perfect color correction from the ultra-violet to the mid-infrared, exhibits a wide field of view, dramatically reduces group delay dispersion and significantly improves throughput by eliminating the center obscuration all together. This lens not only advances existing NLO modalities that rely on broadband radiation, but also enables new technologies such as photothermal imaging and SFG microscopy that have thus far suffered from low performance focusing optics.

NIH Research Projects · FY 2024 · 2023-07

Project Summary Alzheimer’s Disease (AD) is the most common cause of dementia in elderly populations. The development of effective treatments for this progressive neurodegenerative disorder has been hindered by our lack of understanding of the disease. AD is classically characterized by amyloid-β (Aβ) plaques, neurofibrillary tangles, and brain-wide neuroinflammation which ultimately result in synaptic loss, neuronal dysfunction, and cognitive impairments. With our incomplete knowledge of the mechanisms underlying the emergence of these pathological hallmarks, we must focus on understanding the different aspects of disease pathology to successfully create therapies treating AD. Genome wide association studies (GWAS) have implicated microglia, the tissue-resident macrophages of the brain, as mediators of disease pathogenesis. Microglia actively maintain tissue homeostasis in the healthy brain including the regulation of lattice-like extracellular matrix (ECM) structures called perineuronal nets (PNNs). PNNs enwrap the soma and proximal synapses of different neuronal subsets and aid in learning/memory consolidation. While PNNs are naturally lost with age in wild-type (WT) mice, this loss is exacerbated in AD. Interestingly, when microglia are eliminated in the AD transgenic 5xFAD mouse model, 1) plaques fail to form and 2) PNN loss is prevented, altogether suggesting PNNs play a protective role. However, the consequences of PNN loss in AD remain unknown. To that end, we have developed two approaches to ablate PNN structures both before and after the onset of plaque deposition in order to determine their role in plaque formation, synaptic loss, and neuronal loss. In this proposal, I will determine the impact of PNNs in AD pathology by pursuing two important questions: 1) does the loss of these ECM structures facilitate plaque formation and 2) does PNN loss make neurons more susceptible to damage? Collectively, this proposal will elucidate the role of PNNs in AD – before and after the onset of plaque pathology – by exploring how their experimental ablation will affect plaque deposition, synaptic loss, and neuronal loss. Establishing whether PNNs can prevent plaque deposition as well as determining whether PNN loss in AD renders neurons more susceptible to damage is highly relevant and could lead to new therapeutic avenues that target genes/ proteins involved in PNN synthesis and degradation.

NIH Research Projects · FY 2024 · 2023-07

PROJECT SUMMARY This multi-PI proposal is a collaboration among tissue engineers and an orthopaedic surgeon to develop a liquid cartilage filler, called chondrogel, that would be efficacious in repairing gouge and focal defects of the knee using an arthroscopy approach. Chondrogel is formed using extensively passaged, allogeneic rib chondrocytes that have retained their ability to form mechanically robust neocartilage that is phenotypically akin to articular cartilage (e.g., production of collagen II and lubricin, absence of collagen I and X). Preliminary data show that chondrogel fills gouge defects in explant culture and also in vivo after 16wks in the minipig knee. We have also developed arthroscopic techniques for the minipig. In this proposal, we will show that, in addition to gouge defects, chondrogel will be effective in healing focal defects as well when administered arthroscopically. This will be achieved in two aims. In Aim 1, we will examine chondrogel 1) to show that, in addition to 20x1mm gouge defects, chondrogel is capable of filling focal defects 5mm in dia. in explant culture (Aim 1, Phase I), and 2) to find the maximum arthroscopic intraarticular pressure where chondrogel is still retained in gouge and focal defects (Aim 1, Phase II). In Aim 2, we will determine if chondrogel heals gouge and focal articular cartilage defects in the minipig using arthroscopy. Because chondrogel has been designed based on surgeon surveys and because it is based on rigorous science demonstrating its ability to form cartilage, successful completion of this proposal would allow the use of arthroscopy to treat cartilage defects.

NIH Research Projects · FY 2025 · 2023-07

PROJECT SUMMARY The development of an organism requires a delicate balance of cell proliferation with cell cycle exit events that necessitates the regulation of the cell cycle machinery to interface with the developmental program. Among critical cell cycle exit events during development are cell differentiation and cell cycle pause, also known as quiescence. The decision to proliferate or exit the cell cycle is influenced by a multitude of factors, including developmental, environmental and nutritional cues. Failures in these decisions are the cause of cancer, as well as developmental abnormalities and aging-related disorders. My overarching goal is to address how the core cell cycle machinery integrates diverse inputs to execute the decision to enter and exit the quiescent state and to couple the cell cycle to cell fate determination during development. My prior work employing C. elegans provided fundamental new insights into the control of cell cycle state transitions in an in vivo context. Using the developing germline, a tissue of utmost importance for the accurate propagation of the genomic information across generations and where cell cycle regulation is tied to nutrient signaling, I uncovered a conserved molecular mechanism that allows for the accumulation of cyclin B to drive entry into mitosis. I also determined how the cell cycle machinery is specialized in different developmental contexts to promote cell proliferation, with particular emphasis on the Cdk1-Cyclin B complex that coordinates mitotic entry and exit events. In this proposal, my group will capitalize on our expertise in cell cycle regulation mechanisms, in vitro biochemistry and developmental analyses to delineate the molecular mechanism by which germline precursors enter into and exit from a non-cannonical form of quiescence at the G2 stage of the cell cycle in response to nutrient signaling, to address how these signals interface with the pathways that regulate entry into mitosis, and to determine how the cell cycle machinery intersects with cell fate specification to promote cell differentiation during embryonic development. This work will drive new understanding of how cell cycle decision points are regulated during development, which could help prevent and/or treat disorders originating from cell proliferation defects.

NIH Research Projects · FY 2025 · 2023-07

Abstract Ischemic coronary heart disease is the world’s leading cause of mortality and morbidity. Within this complex disease entity, many patients suffer from myocardial ischemia but are found to have no obstructed coronary arteries (INOCA). These patients have a high risk of cardiovascular events. Yet current methods for accurately diagnosing and assessing the physiological effects of INOCA are limited. Catheter-based approaches are invasive, with added risk, procedural time, and cost. Positron-emission tomography (PET) and cardiac magnetic resonance (CMR), both noninvasive techniques for clinically assessing INOCA, have limitations such as claustrophobia (CMR), cost and radiation dose (PET), and local expertise and availability (both). None of these noninvasive tests accurately yields both anatomical information on the extent of coronary atherosclerosis and its pathophysiological consequences. We have developed a noninvasive, low-dose dynamic CT perfusion technique that can accurately measure myocardial perfusion in mL/min/g. This procedure combines patho- anatomical assessment using CT calcium and CT angiography, as well as pathophysiologic assessment using CT-derived stress flow (in mL/min/g) and coronary flow reserve (CFR), which are combined to calculate coronary flow capacity. The current study seeks to test this novel cardiac CT method for assessing patients with INOCA. Our technique’s accuracy in measuring stress flow and CFR has been validated in preclinical models, and its preliminary validation, safety, and feasibility shown in patients. We propose to study prospectively its accuracy for assessing INOCA. The study aims to (1) test the hypothesis that rest flow, stress flow, and CFR measured by noninvasive dynamic CT perfusion highly correlate with that by invasive measurement in patients with INOCA; (2) establish a stress flow and CFR reference range determined by noninvasive dynamic CT perfusion that could be used to set the minimum normal thresholds for stress flow and CFR; and (3) test the hypothesis that comprehensive cardiac CT can be used to differentiate between patients with and without physiologically significant coronary artery disease (CAD) in patients with suspected INOCA. Aim 1 will enroll 150 patients with positive stress test and INOCA. Patients will undergo our comprehensive cardiac CT followed by invasive stress flow and CFR tests. Aim 2 will enroll 50 patients with negative stress test and measured invasive stress perfusion greater than 1.21 mL/min/g and CFR > 2.0 to establish the normative range of CT-based stress flow and CFR. Aim 3 will discriminate between patients with and without physiologically significant CAD with dynamic CT perfusion, using invasive stress perfusion and CFR as the reference standard. The study’s successful completion invasive tool that allows comprehensive concurrent evaluation of coronary anatomyand physiology in symptomatic patients with INOCA.

NIH Research Projects · FY 2025 · 2023-07

PROJECT SUMMARY/ABSTRACT Traumatic brain injury (TBI) can lead to cognitive disabilities and epilepsy, but circuit mechanisms remain unknown. I hypothesize that the death of inhibitory interneurons and subsequent reorganization of neural circuitry in hippocampus leads to post-traumatic deficits in spatial coding and memory. To test this, I propose studies to systematically and comprehensively map the progressive structural and functional breakdown of hippocampal neurons in a widely used mouse model of TBI. In Aim 1, I will use advanced whole-brain circuit mapping technologies to visualize the inputs and outputs of hippocampal CA1 neurons in control and brain injured animals. In Aims 2 and 3, I will use calcium imaging with miniature microscopes to determine how spatial coding in hippocampus is altered by TBI and after interneuron transplantation. My long term goal is to build an independent academic career dedicated to developing novel circuit-based therapeutics for brain and spinal cord injury. Achieving this goal will require extensive training in the principles of neurotrauma, physiology and behavior. UCI is an outstanding institution for training in these areas, primarily due to the rich community of prominent neuroscientists and clinicians performing neurotrauma research and the pioneering role of UCI in the neurobiology of learning and memory, epilepsy and behavior. To help me achieve my goals, I have assembled a world-class team of internationally recognized scientists who will provide me with hands-on technical training, formal coursework and career guidance during the award and beyond.

NIH Research Projects · FY 2025 · 2023-06

Project Summary While significant progress has been made in reducing the malaria burden since the turn of the century, the last few years have seen a deceleration of this success and the World Health Organization (WHO) in its 2020 World Malaria Reportestimates ~229 million cases (morbidity) and 409,000 deaths (mortality) in 2019. Approximately 95% of the global malaria deaths occurred in only 31 countries with seven in sub-Saharan Africa accounting for ~51% of all the deaths. Furthermore, the WHO predicts no further significant decreases without greater use of the existing technologies and the necessary development of new tools. The challenges of the continued demand for new drugs and the slow roll-out of an efficacious vaccine makes urgent the need for new, cost-effective and efficacious disease-control tools that are safe for people and the environment. This need justifies efforts to develop genetic approaches for controlling malaria parasite transmission. Long-term, sustainable genetic control will require the deployment of strategies designed to be resilient to the immigration of susceptible mosquitoes and parasite-infected people. Genetically-engineered mosquito strains for population modification have the appropriate performance features for this purpose. Wild mosquitoes immigrating into a region populated by engineered, parasite-resistant mosquitoes will acquire beneficial genes by mating with the local insects, and persons with malaria moving into the same region will not be able to infect the resident vectors, and therefore are not a source for infection of other people. We have exploited the molecular mechanisms of CRISPR/Cas biology to develop autonomous gene-drive systems for site-specific, transgene copy number amplification in the mosquito germline. These drive systems carry a cargo of anti-parasite effector genes that prevent transmission of the parasites by the mosquitoes carrying them. The working hypothesis is that these systems will be able to impact transmission dynamics even if they confer a genetic load that impacts reproductive fitness. We shall investigate the impact of gene-drive system insertions on the recipient mosquitoes to determine effects on reproductive success and drive and effector gene efficacy and stability. Towards these ends, our Specific Aims are: 1) evaluate the impact of autonomous gene-drive systems on the reproductive success of Anopheles gambiae ss. and An. coluzzii and 2) evaluate the multigenerational stability of autonomous gene-drive systems in Anopheles gambiae ss. and An. coluzzii in laboratory cage trials. The successful completion of these Specific Aims will inform plans and modelling for the future use of this technology in malaria control.

NIH Research Projects · FY 2025 · 2023-06

PROJECT SUMMARY Relevance to public health. Microglia, the inflammatory cells in the brain and spinal cord, participate in the development of neuropathic pain (NeuP) after nerve injury by releasing reactive oxygen species (ROS) and proinflammatory cytokines. NeuP affects >16 million Americans, is associated with a severe reduction in quality of life. NeuP is often refractory to conventional analgesics, and opioids have only limited efficacy increasing the risk of their misuse. Medications not typically used as analgesics are often the first-line treatment of NeuP. How- ever, <50% of patients report pain relief with current treatment, and side effects are common. We offer evidence that suppressing the voltage-gated proton channel (Hv1) in microglia can reduce inflammatory mediators release and attenuate NeuP. We propose to identify small-molecule Hv1 blockers by high-throughput screening (HTS) of plant extracts and botanical compounds as a step toward new drugs for NeuP. Brief background. This application builds on: (i) our publication that Hv1 controls ROS and proinflammatory cytokines release in microglia and contributes to the development of NeuP, (ii) our preliminary finding that C6, a designer peptide blocker of Hv1, suppresses ROS and proinflammatory cytokine release by microglia and atten- uates NeuP after peripheral nerve injury in mice, and (iii) our successful pilot screening of a small compound library and eight exemplar plant extracts using a novel live-cell, fluorescence-based HTS assay. The HTS assay employs a pH-sensitive fluorescent protein genetically linked to the human Hv1 channel (hHv1-VFP-H148G), allowing real-time monitoring of Hv1 operation and the identification of Hv1 blockers. Unique features and innovation. Our target choice is innovative because no clinically approved drugs se- lectively target microglia and Hv1 lacks potent and specific small-molecule blockers. Our HTS assay is innovative because there is no reported HTS method for proton channels. We identified unique reagents: C6 (the first specific blocker of Hv1), C6 variants, F6 (a small molecule that inhibits Hv1 in the HTS), and Lavender (a plant extract that inhibits Hv1 in the HTS) to facilitate the development, refinement, and validation of the HTS assay. We will employ the HTS assay to screen a unique plant extract library with >1,500 species (with >15,000 esti- mated compounds), many of which have been used historically for anti-inflammation and pain-relief. Three specific aims. (1) Optimize the HTS assay (R61 phase) seeks to improve and validate the HTS assay for plant extracts and botanical compounds. (2) Select leads from a unique library of plant extracts (R33 phase) seeks to screen the plant extracts library and identify potent and specific botanical Hv1 blockers. (3) Study sup- pression of the microglial inflammatory response and NeuP with identified botanical Hv1 blockers (R33 phase) seeks to validate the efficacy of identified botanical Hv1 blockers in microglia cells and a mouse model of NeuP. Significance. This work addresses an unmet medical need for NeuP therapeutics and has a broader influ- ence because Hv1 in microglia is complicit in additional inflammatory disorders, such as ischemic stroke.

NIH Research Projects · FY 2026 · 2023-06

Project Summary Alzheimer's disease (AD) is an age-related, progressive neurogenerative disease that leads to loss of brain cells and their connections. The existing literature provides a broad view of AD/ADRD-related molecular changes from heterogeneous cell populations. However, cell-specific and brain-region specific AD/ADRD-related loss of cells and connectivity is not yet resolved, particularly at a mechanistic level. In response to RFA-AG-23-028, we have assembled a strong multi-investigator team across multiple institutions with complementary expertise in single-cell transcriptomics and epigenomics analysis, neural circuit mapping, and next-generation AD mouse model development. We will use multiple complementary lines of tau mouse models, in conjunction with APOE genetic modulation or pathogenic triggers in targeted brain regions. 1) We will use the Tau P301S transgenic mice on either a human APOE4 knock-in background (TE4) or a mouse Apoe knock-out background (TEKO). TE4 knock-in markedly exacerbates tau-mediated neurodegeneration, while TEKO mice show largely attenuated neuronal loss and brain atrophy compared to P301S mice. 2) We will additionally use recently developed novel humanized Tau mouse models that replace the endogenous mouse MAPT gene with either a normal or pathogenic variant of the entire human MAPT gene (MAPT gene replacement, MAPT-GR), which express all isoforms of human tau at physiologic levels and ratios. We hypothesize that vulnerable cell types in early AD- impact brain regions (locus coeruleus, entorhinal cortex, and hippocampal CA1 and subiculum) show early maladaptive gene expression profiles and epigenomic signatures that define their molecular vulnerability during AD/ADRD pathogenesis. To test our hypothesis, in Aim 1 we will apply single-cell epigenomics and transcriptomics technologies to early AD-impacted brain regions in age-matched control and AD mice, creating cell-type-resolved multi-omic maps of gene expression and chromatin accessibility. Tauopathy progression unfolds in an age-dependent manner, thus we will compare control and pathological tau model mice at two different ages each for different mouse lines (4 months, 10 months for TE and TEKO; 6 months, 12 months for MAPT-GR lines) based upon their behavioral and neuropathological characterization. In Aim 2, we will use the multiplexed error-robust fluorescence in situ hybridization (MERFISH) technology to generate single-cell resolution spatial transcriptomic maps for the early AD-impacted brain regions. MERFISH will extend single-cell omics and spatial genomics to map neural circuits and pathologies at high spatial resolution. In Aim 3, we will use perform computational analysis to integrate single-cell multi-omics data, image-based anatomical and molecular gene expression maps from Aims 1-2, acquired from different mouse models at different ages, to fully characterize the neuronal circuits and AD-vulnerability at cellular level. The proposed research is well aligned to the RFA goals and is expected to provide new biological insights into AD/ADRD pathogenesis at unprecedented cellular and spatial resolution.

NIH Research Projects · FY 2026 · 2023-06

PROJECT SUMMARY/ABSTRACT Influenza virus infections cause significant global morbidity and mortality and pose a serious pandemic risk due to the virus’s propensity for reassortment and mutation. Current influenza vaccines elicit strain-specific responses and are only 10-60% effective depending on the year. There is an urgent need for a universal influenza vaccine that elicits robust, persistent, and broadly cross-reactive B and T cell responses. Designing such a vaccine will require a comprehensive understanding of how features from both the host and the antigen modulate the magnitude, quality, and breadth of the influenza-specific response. Most human influenza studies have been limited to peripheral blood sampling, even though the critical cellular decisions that lead to productive adaptive immune responses occur within lymphoid tissues. Our long-term goal is to define the dynamics of the lymphoid tissue microenvironment, including cell-cell interactions and signaling pathways, that elicit protective immune responses in humans. Our central hypothesis is that immune signatures from mucosal lymphoid tissue are significantly more informative than peripheral blood in developing immunization strategies that elicit robust and broadly cross-reactive influenza responses. To address this question, we propose to leverage a high throughput in vitro organoid platform derived from primary human tonsil tissues. Tonsils are considered both lymphoid and mucosal tissues; they are also accessible from otherwise-healthy patients undergoing tonsillectomy for hypertrophy or obstructive sleep apnea. Participants are demographically diverse and cover the full human age span; males and females are represented at similar proportions. Immune organoids derived from tonsils accurately model human germinal center responses, specific antibody secretion, and T cell activation in response to influenza antigens. They are also able to capture host-mediated inter-individual immune variation related to patient age, sex, and immune history. Furthermore, tonsil organoids can be used to track the kinetics of the adaptive immune response and enable the mechanistic insights needed to rationally design a universal influenza vaccine. The goal of this application is to understand how host features and influenza antigen features contribute to both the magnitude and quality of the influenza immune response in humans. This proposal is supported by strong preliminary data and if successful, will open new areas of investigation for universal influenza vaccine development by identifying correlates and predictors of protection. We will combine comprehensive phenotyping and mechanistic experimental approaches to define the key drivers within human lymphoid tissues that lead to narrow, strain-specific responses. The novelty of this application lies in the systems immunology approach that integrates demographic, serological, phenotypic, functional, and repertoire readouts in a well- controlled immune organoid platform. Completion of the proposed experiments will help us rapidly identify correlates of protection and guide the design and testing of a broadly cross-reactive universal influenza vaccine.

NIH Research Projects · FY 2025 · 2023-06

Project Summary Candidate and Career Development Plan: Dr. Browne is an assistant professor practicing vitreoretinal surgery and functioning as an engineer and physician-scientist at the University of California, Irvine. Dr. Browne established his engineering and basic biological sciences skills as a PhD student. He has balanced clinical duties with his laboratory research activities and. His long-term career goals are to engineer functional imaging tools that will advance the understanding of early and advanced eye diseases and facilitate the therapies needed to treat humans. His training thus far has been using in vitro imaging alone. To achieve his career goals, he is requesting support for training to develop functional imaging tools in vivo and the molecular tools to correctly interpret Two-photon imaging (2PI) observations from animal models. This K08 award will enable Dr. Browne to develop his scientific and professional skills in advanced imaging, fluorescence microscopy, and retinal cellular biology applied in vivo. Dr. Browne and his co-mentors, Drs. Palczewski, Seiler and Kuppermann, have developed a hands-on strategy to fulfill the training requirements through relevant course work, didactics, laboratory techniques, and collaborations at UC Irvine. The training program will prepare Dr. Browne to submit R01-level proposals to independently investigate and optimize functional retinal imaging as a tool for therapeutic discovery. Research Plan: Many blinding retinal conditions, like age-related macular degeneration, are the consequence of biochemical dysfunction and the secondary effects of inflammation and cell death. Conventional clinical tools provide valuable structural information about the retina but are unable to visualize retinal function. Non-linear optical imaging can now reveal subcellular biochemistry in vitro and has emerged as a reliable tool to study retinal disease. 2PI in mouse models demonstrates subcellular changes in energy and light cycle metabolism. Cell replacement therapy has emerged as a therapeutic candidate for advanced vision loss, and preclinical trials in rats have demonstrated visual function restoration. To understand metabolic function in retinal organoids (RtOg) before and after transplantation into blind rats, we will employ functional 2PI in vitro and in vivo as outlined in the following specific aims. 1) Investigate RtOg maturation with 2PI and correlate functional imaging data with cell-specific reporters in vitro and molecular signatures post vivo, 2) Identify functional imaging biomarkers for in vivo metabolism using 2PI of normal rats and rat with retinal degeneration, 3) Study in vivo functional 2PI of transplanted RtOgs in rats to identify alterations in functional imaging biomarkers and correlate imaging findings with visual function testing. Completion of these aims will yield time-resolved metabolic detail for specific cell populations in developing RtOgs, avail novel in vivo information about retinal biochemistry in healthy retina, diseased retina, and diseased retinas treated with retinal sheet transplantation. These discoveries will guide future translation of both functional imaging and tissue replacement therapy in humans.

NIH Research Projects · FY 2026 · 2023-06

ABSTRACT Memory impairment is a common and devastating comorbidity of temporal lobe epilepsy. The network mechanisms underlying memory impairments are poorly understood. Micro-electrode recordings from temporal lobe epilepsy patients reveal frequent focal epileptic discharges (FEDs) that are only detectable with invasive recordings. Preliminary studies performed in our laboratory in a chronic epileptic mouse model revealed that mice experience frequent FEDs while they performed a spatial working memory task. Intriguingly, FEDs occurred robustly at specific locations on the maze, where healthy hippocampus normally generates population activity (sharp wave ripples, SWR) necessary for working memory. These data support the overall hypothesis that the cellular networks that normally partake in memory processes are hi-jacked by FEDs. We will test this hypothesis with three aims. For Aim 1 we will perform large scale tetrode recordings from freely moving mice to test the hypothesis that neurons active during FEDs overlap with neurons active during working memory SWR (wm-SWRs). For Aim 2 we will combine high-density linear probe recordings and chemogenetic inhibition to test the hypothesis that FEDs are generated in the CA3 region of the hippocampus. Finally, in the same animals as used in Aims 1 and 2, we will perform multi-day 24-hour recordings to test the hypothesis that FEDS occurring during working memory share cellular and network mechanisms with the early phase of behavioral seizures. The proposed research could help fill vital gaps in our knowledge about focal epileptic discharges – both in terms of their mechanisms and how they impact memory processing. We hope to elucidate which neurons participate in them, develop selective interventions to inhibit them, and determine how they impact behavioral seizures.

NIH Research Projects · FY 2025 · 2023-06

ABSTRACT Autophagy is a lysosomal degradation pathway that maintains cellular homeostasis under basal and stress conditions by catabolizing cellular constituents to produce energy and building blocks. Although autophagy is common to all eukaryotic cells, highly specialized cells exploit this pathway to support their unique physiological functions. One such example is cone photoreceptors, where autophagy promotes survival during periods of metabolic or light-induced stress. The function of cones as our daytime photoreceptors depends critically on the rapid recovery of their sensitivity after exposure to bright light, a process known as dark adaptation. This metabolically-demanding process is driven by the turnover of chromophore for the regeneration of cone visual pigment and by the resetting of the efficiency of synaptic transmission between cones and cone bipolar cells. As autophagy is intimately involved in cellular metabolism, we will test the novel hypothesis that autophagy modulates the cone-driven photopic dark adaptation. We will perform experiments to determine the physiological conditions that activate autophagy in cones, focusing on bright light exposure, fasting, and physical exercise. We will also determine the subcellular compartments in cones where autophagy is upregulated in response to a range of stress conditions. To investigate the role of autophagy in cone-driven photopic dark adaptation, we will perform electrophysiological experiments to determine how fasting, exercise, or genetic block of autophagy affect the recovery of photopic function following exposure to bright light. Finally, we will evaluate two alternative mechanisms by which autophagy could be modulating photopic dark adaptation, either by accelerating the turnover of visual chromophore or by enhancing synaptic transmission. These experiments will establish autophagy as a novel mechanism for regulating the function of mammalian cone photoreceptors and photopic vision. They will also pave the way for future translational studies with humans seeking to prevent vision loss and enhance photopic vision by intermittent fasting or exercise.

NIH Research Projects · FY 2026 · 2023-05

Santa Ana in Orange County (OC), California (CA) is a predominantly low-income city that is bound by multiple freeways, has a large industrial corridor, and has 65% of houses built prior to 1960. Residents of Santa Ana have identified lead (Pb) exposure as a major health concern. Responding to the problem, we established the Lead-Free Santa Ana! participatory research partnership to characterize Pb levels in soil in Santa Ana since 2017. In this study, we propose to investigate how lead exposure impacts children’s health and academic performance using a participatory research approach. We will also address important gaps in previous Pb research and practice, including 1) limited consideration of both life course exposure and susceptible time window for chronic low-level Pb exposure; 2) lack of research based on repeated outcome measures; 3) few studies on synergistic effect of metal mixtures; 4) few studies on multi-level (e.g., household, school, neighborhood) solutions; and 5) lack of research devoted to leveraging knowledge to inform effective solutions for reducing soil-based Pb exposure to ensure the exposed children have an opportunity for academic achievement. Our overarching goal is to examine associations of life course and current Pb exposures with children’s academic performance and neurobehavioral outcomes, identify harmful patterns and functional implications of current Pb exposure, and develop and implement a prevention and improvement plan (PIP), with particular attention to health solutions. The study population involves 600 children 6-10 years old at enrollment and their primary caregiver. Individual-level exposure to Pb and other metals will be estimated from: 1) deciduous tooth-based exposure at a weekly resolution from the 2nd trimester of gestation up to the 1st year of life and every 6-months from age 1 up to the time when the tooth is shed; 2) blood and saliva for current exposure. Repeated outcomes include 5 years of academic performance and 3 years of behavior outcomes based on the validated Child Behavior Checklist (CBCL) questionnaire. We will examine associations of academic performance and behavioral outcomes with deciduous teeth-based early life Pb exposure (Aim 1) and current blood Pb exposure (Aim 2). Further, we will develop, disseminate, pilot, and evaluate a multi-level (e.g. household, school, neighborhood, city, county) prevention and improvement plan (PIP), with a focus on solutions (Aim 3). The strengths of this study include: bridging participatory methods and implementation science by leveraging results from Aims 1-2 of this study and practice-based evidence to inform the PIP, strong neighborhood and university leadership, life course measurements of Pb and metal mixtures, a large prospective cohort with longitudinal measurements of both exposure and outcomes, and multiple levels of assessments (i.e. household, school, neighborhood) that advance the science on children’s health irregularities to develop, evaluate, and pilot action plans and solution-driven interventions. We will advance knowledge on how low levels of Pb exposure over the life course adversely affect children’s school performance and behavioral outcomes. The practice-based value of this study is noteworthy, as it integrates etiologic data and practice-based evidence to a solutions-oriented multi-level action strategy to improve child academic and neurodevelopmental outcomes.

NIH Research Projects · FY 2026 · 2023-05

Project summary: The long-term goal of my research program is to understand, in detail, the mechanisms of mammalian mRNA 3’ processing and its regulation. mRNA 3’-end formation, typically involving an endonucleolytic cleavage followed by polyadenylation, is an essential step of eukaryotic gene expression and it significantly impacts many aspects of RNA metabolism, including mRNA stability, subcellular localization and translation. In addition, the majority of eukaryotic genes produce multiple mRNA isoforms with distinct 3’ ends through alternative polyadenylation (APA). Recent studies have revealed that APA is highly regulated in development and plays an important role in post-transcriptional gene regulation. Aberrant APA patterns have been associated with a wide range of diseases, from cancer to neurological disorders. Key outstanding questions in the mRNA 3’ processing field include: 1) what is the structure-function relationship of the mRNA 3’ processing complex; 2) how is mRNA 3’ processing regulated by cell signaling; 3) how is APA regulated by RNA-binding proteins? We will address these questions by using biochemical, structural, and genomic analyses. The results of these studies will not only provide novel insights into this key step in eukaryotic gene expression, but also pave the way for developing novel therapy for many diseases.

NIH Research Projects · FY 2026 · 2023-05

Years of study and theory about the unique role of the hippocampus in storing new memories has led to a general idea that the hippocampus generates a unique output code for every unique experience, that is projected back to the neocortex, where it becomes coupled to attributes of the experience that are widely dispersed over the cortex, thus enabling their coherent retrieval. Hippocampal cellular firing, which is rooted in a self-motion based spatial framework, so-called, 'place cells', is modulated by the attributes of each experience (what actually happens at a given location, including sensory input, motor output, and internal brain states such as plans, and 'working' memory). How these memory 'indexes' impact the representation and storage of memory in cortex, at the neural population level, is not understood. We showed that hippocampal output enables the formation of unique, memory-related codes in superficial neocortex (the main target of hippocampal output). Similar to hippocampal 'place' cells, these codes take the form of position correlated cells (PCCs) that participate in sparse, orthogonal representations, corresponding to position and experience in a virtual reality environment (VRE). We have also shown that, like the behavioral manifestations of episodic memory and its derivative, generalized knowledge, these codes survive subsequent damage to hippocampus, and exhibit pattern completion and error correction in the face of cue deletions and rearrangements. These, and related, findings open up a new domain of cortical memory research, and many important questions arise concerning the origins of PCC spatial tuning, the exact role of top-down (hippocampal) and bottom-up (sensory) convergence of inputs to superficial cortex, including off-line replay, and the plasticity rules governing the creation and stabilization of cortical PCCs and their ability to exhibit pattern completion - a sine qua non of associative memory. We propose to explore these questions in mice in a VR paradigm. We will apply a combination of mesoscopic 2- photon and wide-field Ca2+ imaging, optogenetic and chemogenetic manipulation of hippocampal and cortical activity, multi-neuron electrophysiological recording of hippocampal and cortical neural ensembles and LFP dynamics, and cortical microstimulation of unique subsets of superficial neurons. The latter may enable artificial creation of new PCCs and their insertion into ongoing memory representations. Specific experiments include: 1) Testing, using optogenetic inactivation of hippocampus during replay events (Sharp-Wave-Ripples), whether off-line replay of hippocampal patterns contributes to the emergence of cortical PCCs. 2) Defining the role of bottom-up sensory inputs in the formation and subsequent expression cortical PCCs. 3) Exploration of the synaptic plasticity rules governing emergence of cortical PCCs. These experiments will provide a better understanding how hippocampal outflow to neocortex guides the emergence of new cortical feature detectors and schemas, and a framework for future studies on how this crucial function is degraded during normal aging and degenerative brain disorders.

NIH Research Projects · FY 2026 · 2023-05

Project Summary This project will develop a wearable continuous monitor for reporting and predicting physiological state during trauma, shock and sepsis with the goal of predicting morbidity, mortality, and providing feedback during medical intervention. I can also be used as a triage tool. The proposed technology responds to technology gaps published by the Department of Defense Combat Casualty Care Research Program and an NIH Notice of Special Interest in Physiological Monitoring and Point of Care Technologies for Trauma Care. The hybrid technology has an ultra- thin flexible multiple analyte sensor placed just under the skin attached to a flexible wearable patch for non- invasive hemodynamic monitoring. Together these technologies provide real time monitoring of blood oxygenation, heart rate, lactate, tissue oxygen, glucose, and pH. In Aim 1 we will design and construct a minimally invasive continuous sensor for glucose, lactate, oxygen and pH. It has been shown that frequent monitoring of these analytes not only identifies risk at initial injury, but can predict morbidity and outcomes, guide intervention, and stratify medical conditions associated with trauma that may have overlapping or cryptic symptoms. In Aim 2 we will design and construct a wearable patch that operates the sensor developed in Aim1 and further includes the non-invasive technology of pulse oximetry, autonomous operation, and wireless telemetry. The wearable and sensor are both made of flexible circuits providing comfort and mechanical matching of the indwelling component, and conformal attachment of the wearable to the skin. In Aim 3 we will conduct a study using a porcine model of hemorrhagic injury and sensor-guided resuscitation. At the completion of the grant, we will have a validated monitoring technology and can begin the process of applying for an Investigational Device Exemption from the FDA to proceed to human studies.