North Carolina State University Raleigh

NIH Research Projects · FY 2025 · 2024-09

ABSTRACT The objective is to demonstrate feasibility of LQUS in human patients for assessing the severity of pulmonary edema due to heart failure and of idiopathic pulmonary fibrosis. The long-term goal is to develop LQUS to monitor pulmonary edema and fibrosis with high sensitivity and specificity in real time, in vivo, in humans. In patients with lung diseases such as pulmonary edema or fibrosis, diagnosis and monitoring is done using chest X-ray and CT scanning, or invasive pulmonary function tests. However, these imaging modalities expose patients to ionizing radiation, have high inter-observer variability, and are expensive and impractical for frequent routine monitoring. Pulmonary function tests are effort dependent and coughing and shortness of breath may affect the results. Therefore, the need for an in-vivo, point-of-care, real-time, non-ionizing, and noninvasive quantitative monitoring of pulmonary edema is great. Conventional ultrasound remains challenging in the lung because the air-filled alveoli cause multiple scattering. Vertical artifacts called B-lines can be observed with various lung diseases. Although they have some diagnostic relevance, these artifacts are operator- and system-dependent. More critically, they are qualitative and not specific. A need exists for the development of QUS biomarkers of the lung, to monitor chronic conditions leading to interstitial lung diseases such as cardiogenic pulmonary edema and idiopathic pulmonary fibrosis. We propose to develop new LQUS-based metrics of the lung parenchyma. We will develop methods to mitigate chest-wall effects and optimize the data acquisition for humans (Aim1), and apply LQUS methods in-vivo in humans with HF (Aim2) and with pulmonary fibrosis (Aim3).

NIH Research Projects · FY 2024 · 2024-09

Stroke is a leading cause of mortality and chronic disability, which predominately occurs due to blood clots or plaques impeding the blood flow in the brain (ischemic stroke) or a rupture in brain arteries (hemorrhagic stroke). Minimally invasive endovascular procedures, e.g., thrombectomy (removing clots to restore blood flow) and neurovascular embolization (deploying coils in aneurysms to obstruct blood flow), are employed to treat these two strokes but also pose risks for X-ray radiation exposure. Robots were introduced to safeguard operators from radiation and increase precision via teleoperated control several meters away from the patient. However, these robots are bulky capital equipment and only mechanically compatible with a few instruments. To tackle these limitations, we developed a versatile 4-DOF robot with a significantly smaller size than state-of-the-art robots and is compatible with a wide variety of instruments. To further improve effectiveness and usability of endovascular robots, we identify three key limitations to the widespread adoption of robotic systems: 1) prolonged procedure time due to frequent robotic to manual conversions due to lack of full actuation of instruments; 2) steep learning curve and long training time for clinicians to implement complex surgical manipulation with robots to perform interventions due to the lack of coordinated control and pre-operative training of robot-assisted procedure; 3) elevated risks of vessel or aneurysm ruptures due to lack of haptic feedback for instrument-vessel interaction force. Our interdisciplinary team, consisting of experts in robotics (Su), mechanics (Jawed), interventional neuroradiology (Tateshima, M.D.), anatomy (Hartstone-Rose), human-robot interaction (Joo) will: 1) develop full actuation (avoid manual loading/unloading of instruments), coordinated control paradigms, and patient-side haptic module for our robot; 2) establish a machine learning-assisted physics-based simulation framework for pre-operative training and intra-operative situational awareness; 3) study human-robot interaction to evaluate multiple metrics about manual, partial actuation, and full actuation procedures. Our goal is to design intelligent robots in concert with pre-operative virtual training and intra-operative virtual fixtures (safety zone) to improve effectiveness and usability, thus ultimately enhancing safety and clinical outcome of neurovascular interventions. RELEVANCE (See instructions): Our project entails transformative methods that span design, simulation, and medicine for an in-depth understanding of human-robot interaction for a surgery that saves the lives of millions of humans. Our work will advance two fundamental science disciplines: Robotics and Mechanics, and will make scientific contributions to computer sciences and engineering to improve fundamental understanding of medicine.

NIH Research Projects · FY 2025 · 2024-09

Project Summary The overarching goal of the PI’s research program is to decode the intricate biophysical and biochemical functions in diverse molecular processes underlined by the interplay among individual biomolecules and the nanoscopic local environments. To achieve this goal, the proposed research program will focus on the tailor- design of switchable and functional fluorophores and the integration of the probes with multi-dimensional single- molecule imaging (md-SMI) techniques for multi-functional super-resolution microscopy (mf-SRM) and spatially- resolved single-cell multi-omics. Super-resolution optical microscopy has enabled the visualization of subcellular structures and protein molecules with resolution down to the true molecular level (< 5 nm). However, the functional information (i.e., how the biomolecules and the environments interact with each other) within the complex biological system remains elusive. A major bottleneck in decoding the functional information at the single-molecule level is the incompatibility of the existing fluorophores for mf-SRM. Specifically, the (switchable) fluorophores used in existing super-resolution microscopy are predominantly exploited to label and locate the biomolecules and engineered to impose minimal changes responding to the environment thus incompatible in functional imaging. Fluorescent sensors, on the other hand, have been extensively explored to report environmental changes by capturing fluorescent responses (e.g., spectra, lifetime, polarization, intensity) to the environment at the ensemble level. Yet, conventional fluorescent sensors are dim, non-switchable, and lack subcellular molecular specificity, which are key requirements to operate mf-SRM. To address this challenge, therefore, we propose to develop a toolbox of fluorescent sensors as single-molecule functional probes toward mf-SRM. Four research thrusts will be pursued: (1) chromophore engineering to decouple intrinsic fluorescence inhomogeneity at the molecular level from its nanoenvironment factors for hyperplexed mf-SRM strategy for complex molecular interaction imaging related to the chromatin remodeling processes and their coordination with transcription factors, (2) leveraging the development of single-molecule biophysical probes to study the role of the physiochemical functional changes within the higher-order chromatin structure packing/unpacking processes on the epigenetic, (3) developing photon upconversion-based fluorophores for simultaneous near-infrared excitation towards parallel super-resolution interaction and functional imaging. The successful accomplishment and dissemination of the proposed functional fluorophores and enabled mf-SRM imaging capabilities in (a) multi- molecular interaction and (b) mapping the distinct nanoscale biophysical landscapes of subcellular architectures in live cells are anticipated to have an immediate impact on enabling new experimental and computational studies in the fields of chromatin epigenetics and spatially-resolved omics. The newly developed fluorescent probe toolboxes will further promote scientific discoveries and innovations in a wide range of biomedical questions in the fields of epigenetics, chromatin biology and cell biology

NIH Research Projects · FY 2024 · 2024-09

ABSTRACT Terpenoids are the largest class of naturally occurring small molecules. While the majority of terpenoids originate from plants and fungi, bacteria are also capable of producing them. Terpenoids are generated from sequential additions of isoprene units, followed by derivatization via terpene synthase and cyclase enzymes. We have analyzed Human Microbiome Project metagenomes using secondary metabolite prediction algorithms and found that half of all human gut microbiomes carry at least one terpene biosynthetic pathway. We also recently leveraged a high-throughput functional metagenomics approach and discovered that a histidine phosphatase present in the human fecal microbiome without homology to known terpene synthases catalyzed the formation of terpenoids. Carotenoids are mainly tetraterpenoids and are vitamin A precursors with important antioxidant, immunological, and metabolic functions. The overall absorption efficiency of carotenoids can be quite low in the small intestine; therefore, a significant quantity of carotenoids is transferred to the colon. When carotenoids enter the colon, they can interact with the colonic epithelium by acting on biochemical pathways, as we have previously shown. Despite this knowledge, how the gut microbiota might transform these compounds and how microbially produced terpenes/carotenoids impact the gut lining are understudied. We have found that 93.3% of subjects from the Human Microbiome Project contain carotenoid-modifying enzymes in their gut microbiota, and over half of these subjects contain a terpene biosynthesis pathway. Other researchers have shown that a reduced abundance of phytoene dehydrogenase in the gut microbiota is associated with symptomatic atherosclerosis, and that gut bacteria synthesize retinoic acid to modulate host immunity. Carotenoids and their microbial derivatives, therefore, have significant health impacts. In support of this, we have found that carotenoids in carrots mitigated obesity-associated gut dysbiosis. Considering all this data, we hypothesize that the human gut microbiome possesses yet-undiscovered terpene synthases and carotenoid modifying enzymes, and microbial terpenoids/carotenoids can display immunomodulatory activities in the colon. To test these hypotheses, we first will use a novel phage-based functional metagenomics approach and high-throughput screens to reveal terpene synthases and carotenoid modifying enzymes. We then will conduct analytical chemistry experiments to characterize the products of these enzymes. Finally, we will illustrate their biological activities in colon cells at the immunological and proteomic levels. Taken together, this work will reveal new chemistry performed by the gut microbiota and its effects on human health.

NIH Research Projects · FY 2025 · 2024-09

PROJECT SUMMARY Here we propose a novel technological platform that enables rapid and unbiased analysis of entire organs at subcellular resolution. An example of application is to study the developmental glial production (gliogenesis) in the mouse forebrain. Glial cells (also called glia), the most abundant cells in the central nervous system (CNS), play key roles in formation and modulation of myelin, synaptic transmission, and more. Many developmental and adult cases of CNS injury and degeneration such as Alexander disease, multiple sclerosis and Alzheimer’s disease are also associated with alterations in the development of glia. Unlike neurogenesis, gliogenesis remains active and responsive throughout adulthood, making gliogenesis a suitable candidate for future regenerative studies. Therefore, unfolding the mechanisms in which gliogenesis is regulated can provide a way to control the fate of glial cells and, consequently, the ability to reverse neurodegenerative diseases. However, the study of gliogenesis during development and adulthood is technically challenging. Since we use mouse genetic approaches to study gliogenesis mechanistically, our studies necessitate unbiased analyses that require tissue processing, imaging, collection and storage of large datasets, quantification, and regional annotations of the entire forebrain across space and time. This is practically impossible to achieve using classical histology and manual or even semi-automated methods that can take several years per gene. We have established a pipeline for light sheet fluorescence microscopy (LSFM) of tissue cleared (TC) mouse forebrains. The pipeline automatically locates and classifies millions of cells by color and morphology in thousands of images and maps them after registration to established global coordinate system such as the widely utilized Allen Brain Atlas. Combing further software development and hardware innovation, the level of imaging and unbiased analytical system is unprecedented and has the potential to be game-changing, allowing full and detailed cellular and subcellular analyses that have heretofore been unattainable. Specifically, we will: 1) Optimize a pipeline that implements simultaneous and automated detection and classification of multiple cell types in TC brains with LSFM imaging. To accelerate the adoption of such a pipeline in a biology lab, a graphical user interface will streamline the user’s ability to verify the results and to correct for errors using active learning. 2) Deploy a Deep Design (DD) approach for enhancing optical sectioning and multi- color acquisition in LSFM. The success of the DD initiative holds the potential to unlock various applications aimed at enhancing hardware reliant on deep learning for data analysis. Success of these goals will lead to an automated imaging and analysis platform that is developed to address questions in an important biological problem.

NIH Research Projects · FY 2025 · 2024-09

Age-related cognitive changes: Effects of combined flavonoid intake and physical exertion mediated by the gut microbiome Age-related cognitive changes can be the first indication of the progression to dementias, such as Alzheimer's. These changes may be driven by a complex interaction of factors including diet, activity levels, genetics, and environment. Recent in vivo experiments and human clinical trials have shown that flavonoid-rich foods can inhibit neuroinflammation and enhance cognitive performance. Improved cognition has also been correlated with a physically-active lifestyle, and with the functionality, composition, and diversity of the gut microbiome. Research has established that 1) the great majority (+90%) of dietary flavonoids are biotransformed into phytoactive phenolic metabolites at the gut microbiome level prior to absorption, 2) prebiotic- like dietary flavonoids alter microbiota profiles, functionality and diversity, 3) health-relevant outcomes from flavonoid ingestion may only be realized in the presence of a robust microbiome and 4) physical exertion (moderate aerobic exercise) dramatically accelerates the uptake of these gut-derived anti-inflammatory and immunomodulatory phenolic metabolites into circulation. This project's hypothesis is that the combination of flavonoid-rich diet and routine physical activity may potentiate cognitive benefits and reduce cognitive decline in an aging population, via mechanisms mediated by the gut microbiome. Aim 1 will examine the effects of routine flavonoid-rich blueberry intake (12-weeks), combined with or in the absence of regular moderate exercise, on cognitive function in a clinical population of older participants identified as experiencing age-related cognitive changes. Aim 2 will investigate, using shotgun metagenomics, the extent to which observed cognitive function is associated with intervention- induced changes in the microbiome and explore synergies. This Aim will leverage a unique and extensive in-house library of gut-derived phenolic metabolite standards. In Aim 3, the ability to abrogate the microbiome in test animals, unlike humans, will clarify its role in linking diet and physical exertion to cognition in aging brains. A mouse cognitive decline model employing antibiotics will isolate and interrogate the role of the microbiome as a mechanistic target by which dietary flavonoids and/or exertion improve cognitive outcomes. We will humanize the mice using fecal samples collected at baseline from human clinical subjects exhibiting age- related cognitive changes. The overall result of this project will determine how dietary flavonoids (e.g. berries) and moderate physical exertion, as reasonable diet and lifestyle modifications, can impact cognitive change in the aging population via the gut microbiome.

NIH Research Projects · FY 2024 · 2024-09

PROJECT SUMMARY Since any antimicrobial drug use has the potential to increase resistance, a key goal is to align antimicrobial drug use (AU) with the prescribing guidelines in veterinary settings. Awareness alone is inadequate to achieve concordance with prescribing guidelines since other factors, such as perceived pressure to prescribe by clients, hospital culture, and a lack of confidence in communicating with clients have been described as barriers to judicious use. Information is lacking on the impact of available educational resources to reduce veterinarian's intentions to prescribe antibiotics as well as their confidence that they can align their prescribing to AS principles. An area of identified antimicrobial overuse in companion animal medicine is canine acute diarrhea, for which up to 70% of veterinarians have been reported to prescribe or intend to prescribe metronidazole. These factors make it a crucial area for testing the impact of targeted resources designed to persuade veterinarians to reduce antimicrobial use. To foster antimicrobial stewardship in veterinary settings using training or education tools, we will use the Theory of Planned Behavior to quantify the knowledge, attitude, subjective norm (perceived social pressure regarding guidelines), and perceived behavioral control (perceived ability to follow the guideline) related to prescribing metronidazole for dogs with a common medical condition (i.e., acute diarrhea). We will explore whether a short educational video on antimicrobial stewardship or a summary of evidence-based guidance with accompanying citations can impact veterinarians' opinions on prescribing antibiotics for canine acute diarrhea and define characteristics of antimicrobial use resources that veterinarians identify as effective in changing their intention to reduce antimicrobial prescribing for canine acute diarrhea. The impact of these resources will be assessed using a cross-sectional survey of companion animal veterinarians in the United States randomized to 3 arms (no resource, educational video, summary of evidence-based guidance) followed by focus groups with participants drawn from each group to define which aspects of AS resources are effective in reducing veterinarians' intent to prescribe antimicrobial drugs. The outcome of these aims will facilitate a greater understanding of the potential impact of AS resources on aligning veterinary AU with AS guidelines and inform further research into the creation and implementation of resources to companion animal veterinarians to further the goals of antimicrobial stewardship.

NIH Research Projects · FY 2025 · 2024-08

Animal-Assisted Interventions (AAIs) are goal-oriented programs that intentionally incorporate animals, such as dogs, for therapeutic benefits. AAIs are widely used in a variety of settings, especially for cancer patients as well as veterans with Post-Traumatic Stress Disorder (PTSD). AAI has proven to provide physiological, psychological, and symptom benefits. The positive effects of AAI are posited to be, in part, due to the dynamic human-animal bond (HAB). Despite AAI’s popularity, neither comprehensive AAI assessment methods nor stakeholder-informed, standardized AAI protocols exist including activities critical for understanding AAI mechanisms of action, the role of the HAB, and the mechanisms by which the HAB is formed and maintained. Our overall objective is to develop, test, and evaluate an internet of things software and hardware system for dyadic physiological monitoring of humans and animals in AAI settings, and to innovate in analytic methods for interpreting the data. The work is important, careful, and systematic and will yield novel capabilities and information for AAI outcome assessment and intervention development. Our team has developed and tested an innovative platform that incorporates wearable, wireless sensors that will simultaneously gather physiological data (i.e., activity, heart rate/variability, respiratory rate, electrodermal activity) from both humans and dogs involved in AAIs. This novel system will be combined with psychological (i.e., distress, well- being) and symptom data (i.e., pain, fatigue) collected from the patient and dog handler. Tasks will include qualitative methods (i.e., focus groups) to elucidate first stakeholder-informed, standardized AAI protocols. Conducting focus groups including patients, handlers, and providers will provide information to optimize a structured AAI protocol that can be delivered with a high level of intervention fidelity, lead to beneficial patient outcomes, and provide controlled settings for objective, continuous measurement of both patient and dog physiology and behavior. This work will contribute new capabilities for the in vivo study of the human-animal bond in AAI especially in oncology and PTSD settings, and new knowledge about the types of interactions that promote, or result from, stronger human-animal bonds and the role they play in therapeutic outcomes. The populations are large: the U.S. has had 1.3M-1.8M new cancer patients every year since 1999, and it is estimated that 23% of the 2.7M veterans suffer from PTSD. The capabilities and knowledge derived from this project will afford new ways to directly improve the lives of millions of Americans. RELEVANCE (See instructions): The proposed research is relevant to NCI as it will contribute new knowledge and tools that illuminate and enable novel study of the role of Animal-Assisted Interventions (AAI) in oncology treatment. Existing knowledge strongly suggests AAI can improve wellbeing for oncology patients, but structuring AAI sessions to promote improved outcomes has been a process of trial-and-error. The novel tools proposed here will enable new capabilities for customizing AAI for oncology treatment and quantitatively evaluating outcomes.

NIH Research Projects · FY 2025 · 2024-08

Floss: a novel method for oral mucosal vaccination The overall goal of this proposal is to develop a novel method of oral cavity mucosal vaccination. The mucosal surfaces serve as portals of entry for a vast majority of pathogens such as influenza virus and HIV. It is recognized that a strong immune response at both the mucosal and systemic compartments is more effective at combating these infections than an immune response in just the systemic compartment. However, parenteral injections do not stimulate strong mucosal immunity. To achieve this, vaccines must be delivered through the mucosal surfaces. Furthermore, mucosal vaccinations can be painless and better accepted (of course depends on the route) as compared to painful shots. The oral cavity is an extremely attractive route for delivering vaccines due to it’s ease of accessibility and the relatively mild environment compared to the stomach. Within the oral cavity, the buccal and sublingual mucosa have been extensively researched, however, poor permeability of vaccines through these mucosal tissues has made it difficult to translate these routes to the clinic. Nonetheless, research has shown that if vaccines are delivered through the oral cavity, immune responses can be stimulated in the distant vaginal, respiratory, and intestinal mucosa, offering protection at all these other sites. In other words, the oral cavity has potential to be used for vaccination against a broad range of pathogens such as influenza and HIV. Therefore, a breakthrough in successful delivery of vaccines through the oral cavity could have a paradigm-shifting impact on vaccinations. Here we propose that a floss can be used to target the junctional epithelium for vaccination. The junctional epithelium is a unique epithelial tissue that has exceptionally high permeability and provides a doorway into the mucosa. However, because it is located at the base of the gum pocket it is harder to target. We postulate that the floss, a common dental device used by millions, could be coated with a vaccine and used for vaccination. Our hypothesis is that floss-based vaccination through the junctional epithelium can stimulate systemic and mucosal humoral and cellular immune responses against different antigens. This hypothesis is backed by our strong preliminary data. The objective of this research proposal is to build on this preliminary data and develop this novel method of vaccination into a reliable and reproducible method of vaccination. The aims are: i) comprehensive characterization of immune response generated through junctional epithelium immunization in mice, ii) characterization of the nature of immune stimulation following junctional epithelium vaccination in mice, and iii) characterization of systemic and mucosal immunity from floss-based vaccination in pigs. This new approach of vaccination will be assessed in mice and pigs, which increases the translational potential of this work. Because the floss is needle free, it is painless and could be self-applied. It also has potential to be distributed through postal mail, which could make vaccination campaigns easier. Overall, this research proposes to establish a new paradigm in oral mucosal vaccination, which has potential for significant impact on public health.

NIH Research Projects · FY 2025 · 2024-08

PROJECT SUMMARY In the US, variability in weather patterns are creating new health risks and exacerbating existing health disparities in some communities across the Nation. Local health departments and health care systems are front line defenders of the population’s health and play a key role in a community’s resilience to extreme weather. Yet weather-related health risks are not currently prioritized in local or regional community health assessment efforts, particularly in rural areas like Southern Appalachia. Partnerships between hospital, public health, community members, and environmental health scientists are often underutilized channels in examining the health impact of extreme weather as an environmental determinant that works independently and jointly with other social determinants to amplify local health risks. The overarching goal of this community-driven project is to integrate extreme weather impacts into a regional health assessment framework to enhance the capacity of local public health systems to protect the health of rural communities. We will achieve the following specific aims: Aim 1. Integrate extreme weather data into the regional community health assessment and needs process; Aim 2. Engage regional hospitals and public health departments in the identification of local environmental and health priorities; and Aim 3. Co-design targeted communications training for health professions and public health messaging on regional weather and environmental-related health impacts. Our expected outcomes will include the: (1) integration of extreme weather data into a regional community health assessment planning process; (2) identification intrinsic rural community health networks that will inspire commitment and foster capacity for community-wide participation in resilience planning; and (3) targeted communication trainings and public health messaging to advance awareness on extreme weather impacts in the region. This work has the potential to be transformative to the field by providing a public health model for integrating extreme weather impacts in a regional community health assessment process for rural communities. The long-term goal is to advance a national model that demonstrates the identification, prioritization, and implementation strategies to help communities address extreme weather impacts on health. This project will leverage WNC Health Impact, a partnership and coordinated process in existence for over a decade, to engage hospitals, public health agencies, and key regional partners in a 16-county region in rural Appalachia around a vision of improved community health. Results will guide the development of local and regional strategies to monitor and reduce the adverse health effects from extreme weather events.

NIH Research Projects · FY 2026 · 2024-07

2023. NIH MIRA project summary abstract Title: Chemical labeling strategies using biomolecule-compatible, nonaqueous media Abstract: Among many classes of chemical tools devised to date, protein bioconjugation technologies have proven valuable in a wide variety of contexts such as preparation of therapeutic agents and study of disease mechanism The last decade has witnessed a substantial advance in bioconjugation technologies, although challenges of selective and efficient labeling have not been completely addressed to date for many of the 20 canonical amino acids. Our research program tackles the longstanding issues of selective bioconjugation of unactivated amino acids by identifying nonaqueous media suitable for both biomolecules and organic chemistry reactions, which has not been actively pursued to date and is innovative from the applicant’s point of view. Our long-term goal is to develop bioconjugation methods selectively targeting amino acids that were inaccessible by previous approaches in aqueous media. Our overall objective in this application is to discover chemical methods for chemoselective functionalization of hydrophobic, unactivated, and less abundant amino acids, offering higher chance of site-specific modification due to their lower natural abundance and less surface exposure. Our central hypothesis is that nonaqueous media can be compatible with proteins and induce chemical reactions that were not achievable in aqueous medium. The rationale for the proposal is that development of novel bioconjugation methods is expected to become facile by gaining access to a large number of synthetic methodology literature that often relies on nonaqueous media. The proposed research is significant because it is expected to provide a chemical tool to target amino acid residues that were inaccessible by the traditional methods and to provide a new paradigm to create bioconjugates.

NIH Research Projects · FY 2025 · 2024-07

Project Summary Rates of neurodevelopmental disorders (NDDs) with socioemotional deficits are rapidly rising, including general and social anxiety disorders (ADs, more common in women). Although environmental factors, including chemical exposures in early development, are universally thought to increase NDD risk, most work to date has almost exclusively focused on genetic factors. One of the few environmental factors implicated in sex-specifically impacting behaviors relevant to NDDs with socioemotional deficits is developmental exposure to flame retardants (FRs). FRs and its components are widely used in electronics, infant products, and furniture, resulting in ubiquitous human exposure. Our previous work has shown that developmental exposure to the chemical FR mixture Firemaster 550 (FM 550) sex-specifically alters anxiety and social behavior in several species. Since it is challenging to directly link environmental chemical exposure to NDD-relevant behavioral and neural endpoints due to the lack of human-typical social behaviors in many laboratory rodents, we have employed the more human-relevant, spontaneously prosocial animal model, the prairie vole (Microtus ochrogaster). In the prairie vole model, developmental FM 550 exposure sex-specifically impacted anxiety, social interaction, exploratory motivation, and social pair bond formation. The greatest effects were detected in females, who displayed generalized and social anxiety, while males displayed a decreased ability to form social pair bonds. The mechanisms by which FM 550 exposure alters the neural systems that are integral to these behaviors and disorders remain poorly understood, providing the rationale for this proposal. Here we focus on dopamine (DA), oxytocin (OT) and vasopressin (AVP) systems in the social brain neural network (SBNN), which includes sexually differentiated brain regions such as the nucleus accumbens (NAcc) that are key for coordinating NDD-relevant behaviors. We will leverage the prairie vole model and our synergistic expertise in developmental neurotoxicology, autoradiography, genetics, electrophysiology, and neurochemistry to identify how FM550 impacts DA/OT/AVP receptor expression, receptor action on neuron function, and DA signaling as assessed using voltammetry in awake behaving animals. Our central hypothesis is that developmental exposure to FM 550 disrupts DA/OT/AVP receptor density, DA/OT/AVP electrical function, and DA signaling in awake, behaving animals. We address this central hypothesis in voles of both sexes. There are three aims: 1) Test the hypothesis that developmental FM 550 exposure impacts DA/OT/AVP receptor density and related gene expression, 2) Test the hypothesis that developmental FM 550 exposure impacts DA/OT/AVP receptor action on neuron electrical function, and 3) Investigate the effects of developmental FM 550 exposure on DA signaling relevant to social interactions. Overall, the proposed studies are significant and high impact because they leverage a unique model animal with enhanced translational value to identify specific novel mechanisms by which DA/OT/AVP receptors, neuron function and DA signaling are vulnerable to developmental chemical exposures.

NIH Research Projects · FY 2025 · 2024-07

PROJECT SUMMARY/ABSTRACT HIV-1 does not persistently infect macaques due to restriction by several species-specific host factors necessitating the use of chimeric SIV/HIV-1 viruses (SHIVs) as surrogates to model HIV-1 infection in macaques. Infection of macaques with SHIVs is the most preferred model system for vaccine and prevention studies because SHIVs encode HIV-1 Envelope glycoprotein (Env) – the sole target of HIV-1 neutralizing antibodies. Because the goal of vaccines is to prevent new infection, SHIVs based on circulating, transmitted forms of Env variants are desired as challenge viruses. Existing SHIV/macaque models typically employ SHIVs that encode HIV-1 Env from laboratory-adapted viruses, whose neutralization sensitivities differ from circulating Env variants. This significantly limits the ability of the existing SHIV/macaque models to predict efficacious intervention(s) in humans. Development of SHIVs encoding circulating Env variants has been extremely challenging, mainly because such SHIVs replicate poorly in macaques, if at all. To increase their replication and pathogenicity, SHIVs require extensive adaptation in vivo via serial passage in macaques. The process of serial macaque passage results in accumulation of adaptive mutations in Env that facilitates robust replication. Serial passage is typically performed within the first two weeks of infection, a time during which macaques mount a robust type-I interferon (IFN) response to infection. The host IFN response presents an early barrier against infection because production of IFNs upregulates expression of several IFN-stimulated genes (ISGs), which results in induction of an ‘antiviral state’. Proteins encoded by certain ISGs, referred to as restriction factors, act as potent barriers against cross-species lentiviral transmission. Thus, macaque restriction factors have the potential to block SHIV infection as they can antagonize HIV-1 Env. We recently identified macaque interferon-induced transmembrane proteins (IFITMs) as ISGs that selectively restrict replication of SHIVs encoding circulating HIV-1 Env variants. Our preliminary results suggest that unpassaged SHIV is potently inhibited by IFN in macaque lymphocytes. In contrast, serial passaged SHIVs are resistant to IFN. We found that the loss to two N-linked glycans in Env upon serial passage is sufficient to increase replication and confer resistance to IFN. This research proposal will: 1) characterize the adaptive changes in Env of serial passaged SHIVs that increase replication and IFN resistance; 2) determine the role of N-linked Env glycans in SHIV infection of primary macaque immune cell subsets ex vivo, and mucosal transmission and pathogenicity of SHIVs in vivo; and 3) evaluate the contribution of five macaque IFITM homologs, which are upregulated by IFN, in restriction of unpassaged, IFN-sensitive SHIVs. Upon completion, this study will provide mechanistic insights at the host-viral interface that drive selection, adaptation, and pathogenicity of SHIVs in macaques.

NIH Research Projects · FY 2025 · 2024-06

ABSTRACT Fungal infections, particularly Candida albicans (Ca), have a high worldwide disease burden and mortality rate. Unfortunately, antifungal resistance is rising in this pathogen, necessitating the search for alternative treatment modes. Ca can exist in the gut of healthy individuals without causing disease, but can also switch into a pathogenic form. Key drivers of Ca virulence include hyphal growth and biofilm formation that is enforced by its mating pheromone, α-factor. Unfortunately, biofilm formation also reduces the efficacy of antifungal drugs. Therefore, drugs that inhibit the ability of C. albicans to form biofilms in the gut may synergize with currently available therapies to treat Candida infections. Excitingly, Ca biofilms can be inhibited with synthetic peptides or biofilm-degrading enzymes. However, because protein drugs are susceptible to degradation in the gut, delivery of these drugs remains a challenge. Targeted delivery strategies such as liposomes or nano-lipid carriers are promising candidates for this purpose, but release their therapeutic cargo in response to rather crude signals (e.g. mucus or pH) which are relatively uniform in the large intestine. Engineered probiotic microbes are a promising vehicle for delivery of protein drugs into the large intestine. Recent advances in our ability to engineer non-model microbes, as well as an increased understanding of the gut microbiota, have led to a renewed focus in these therapies. Engineered probiotics achieve site-specific protein delivery due to the ability to sense highly specific extracellular cues (e.g. peptide hormones), localize to defined regions of the gut by displaying adhesins on their surface, and secreting recombinant proteins extracellularly. For the purposes of treating Ca biofilms, the probiotic yeast Saccharomyces boulardii (Sb) is particularly promising because of its high secretion rates, ability to easily display recombinant proteins on its cell surface, and its ability to express receptors for the Ca mating pheromone. In this study, we will develop strains of probiotic yeast that can bind to Ca biofilms, secrete biofilm-inhibiting proteins, and sense peptides secreted by Ca during biofilm formation. In doing so, we will generate a lead live biotherapeutic against Ca biofilms that is ready for testing in preclinical models of gut-derived candidiasis.

NIH Research Projects · FY 2024 · 2024-06

ABSTRACT Clostridioides difficile is a clinically important opportunistic pathogen that exploits disruptions in the commensal microbiome of the gastrointestinal tract. C. difficile infection (CDI) is characterized by colitis and diarrhea, which are largely caused by two secreted toxins, TcdA and TcdB. These primary virulence factors bind to the cell surface via their CROPs and internalization domains; upon cell internalization - they glycosylate Rho-family proteins, thus disrupting Rho-dependent cellular processes, ultimately leading to inflammation and increased epithelial permeability. The threat of CDI is rising due to the prevalence of hypervirulent and antibiotic resistant strains. The increasing risk of CDI, combined with the shortcomings of conventional antibiotic and fecal transplantation treatment options, poses an urgent need for novel therapies. Biotherapeutic approaches using monoclonal anti-TcdA/TcdB antibodies indicated a promising route, complementary to antibiotics; however, they suffer from cumbersome administration and limitations in biodistribution. Responding to these challenges, we developed neutralizing peptides that inhibit both TcdA and TcdB and engineered probiotic yeast as a delivery vector of anti-toxin peptides in the colon. In our preliminary work, we computationally designed and evaluated two experimentally effective neutralizing peptides (SA1 and SB6), which demonstrated anti-TcdA and TcdB biorecognition and conferred epithelial protection in primary derived human colonic epithelial monolayers. Additionally, we developed a yeast strain yielding >5 g/L peptide during fermentation after knockout of key proteases. In this work, we propose to implement this toolbox to develop a comprehensive strategy against TcdB-mediated C. difficile infection. To this end, we will computationally design peptides to bind to several domains on TcdB and evaluate a broader set of therapeutic hypotheses at the molecular, cellular, and organismal scales. First, we will elucidate the molecular mechanism of TcdB inhibition by SB6. This knowledge will inform a concerted computational-experimental design of peptides that target the TcdB active domain and neutralize its Rho glycosylation activity. Next, we will use recently published crystal structures and known receptor-binding domains of TcdB to develop peptides that block TcdB’s entry into the cell. These peptides will be inspired by the proteins to which TcdB natively binds on the cell surface, as well as the reference CROP-blocking antibody Bezlotoxumab. Finally, we will engineer probiotic yeast to secrete these peptides, and characterize their efficacy on human colonic epithelial cell and murine animal C. difficile infection models. Collectively, these efforts will elucidate the mechanisms by which inhibitory peptides can block TcdB activity and use this knowledge to develop optimized peptides that inhibit CDI by integrating expertise at the atomic, molecular, cellular, and organismal scales.

NIH Research Projects · FY 2026 · 2024-05

Pulse Electron Paramagnetic Resonance (EPR) spectroscopy is a well-developed indispensable tool for solving complex problems in biochemistry and structural biology. Pulse EPR encompasses several established methods such as double electron-electron resonance (DEER), relaxation-induced dipolar modulation enhancement (RIDME), and double quantum coherence (DQC) spectroscopy that are uniquely suited for obtaining long-range (up to 10 nm or longer) distances and distance distributions between spin labeled sites in biomacromolecules. The distances between endogenous paramagnetic metal centers can also be determined. Another particularly impactful application of pulse EPR is in studies of metalloenzymes, where such methods as 3-pulse electron spin echo envelope modulation (ESEEM) spectroscopy, electron nuclear double resonance (ENDOR), hyperfine sublevel correlation spectroscopy (HYSCORE), and electron double resonance detected NMR (EDNMR) spectroscopy have evolved into highly informative techniques for providing mechanistic details on the function of many important metalloenzymes without the need of preparing protein crystals. However, for all these pulse methods insufficient concentration sensitivity remains the main roadblock towards their broader applicability in biochemical and biophysical research. The goal of this technology development project is to dramatically - by at least one to two orders of magnitude - increase concentration sensitivity of pulse W-band (94 GHz) EPR spectroscopy by developing large-volume, high-quality factor (high-Q), and high finesse microwave resonators based on low-loss dielectric materials. So far this new pulse EPR technology has been only demonstrated as a proof-of-principle and will require further substantial efforts including: (Aim 1) Design and optimization of high volume / high quality factor resonators for pulse EPR for the best concentration sensitivity and construction of the resonator prototypes; (Aim 2) Development of critical mm-wave instrumentation to implement high volume / high sensitivity resonators for routine and advanced W-band pulse EPR experiments; and (Aim 3) Validating the new technology using well studied and well characterized systems. The latter will be done by carrying out 14N ESEEM/HYSCORE experiments with Fe center in myoglobin and di- Mn complexes, evaluating 55Mn EDNMR sensitivity gains for a series of Mn ion complexes, including di-Mn clusters as well as S3 state of the oxygen evolving complex of PSI, and applying the DEER method to resolve distance and angular information for a series of rigid biradicals, transmembrane peptides and rhodopsin oligomers. If successful, this project will provide an innovative technology solution to the paramount long- standing issues of pulse EPR spectroscopy such as increasing both the excitation bandwidth and sensitivity at higher EPR frequencies. This will lead to a broader applicability of pulse EPR methods across the fields of biochemistry and structural biology.

NIH Research Projects · FY 2025 · 2024-04

Several rural communities across the U.S. are burdened by hazardous explosive waste disposal sites, including many active and retired military bases on the National Priorities List. Colfax, LA (2021 pop. 2,010, 71% Black, 26% White, med. income $16,687) currently hosts the only commercially-operating open burn/open detonation (OBOD) hazardous waste thermal treatment (TT) facility in the nation and treats contaminated soils from Superfund sites, spent military munitions, and other explosives. Fine and ultrafine particulate matter (PM) is emitted during TT of Superfund hazardous wastes and military munitions. Colfax residents living immediately south of the TT facility solicited our assistance after enduring health impacts including chloracne, cancers, and thyroid, respiratory, and cardiovascular diseases. During our 2022-23 community-based sampling campaign in Colfax, we detected environmentally persistent free radicals (EPFRs), metals, polycyclic aromatic hydrocarbons, dioxins, and furans in fine and coarse PM samples and collected urine, nail, and dust samples. Beginning December 26, 2023, the Louisiana Department of Environmental Quality will prohibit OBOD, to be replaced with a closed-burn containment system (CBCS) no earlier than 2025. OBOD prohibition aligns with EPA’s efforts to replace OBOD with CBCS, representing an important inflection point in energetic waste management that requires surveillance to ensure that community exposures are sufficiently minimized. However, even CBCS may incur risks. Emissions of chlorinated compounds and some metals associated with thyroid, respiratory, and skin disease are still anticipated with CBCS. For this reason, Colfax residents have asked us to continue surveillance of the air quality even after the cessation of OBOD. We hypothesize that replacement of OBOD with CBCS will cause short-term increases in coarse PM containing perchlorate derivatives, transition metals, and PFAS during construction, followed by a substantial reduction in fine PM and its components once CBCS is operational. Through our work, we will 1) collect ambient particulate matter, household dust, and biological samples at key time periods during and after construction of the CBCS and 2) chemically analyze collected samples to ascertain changes in chemical composition during OBOD operationand the CBCS construction and operation phases. These efforts will allow for ongoing quantification of air pollution to assess risk of oxidative stress and health effects from exposures, leading to timely reporting of risk data to the community. The proposed study is time-sensitive, as it provides a rare opportunity to compare the emissions and exposures during operations of different technologies and during the transitional period of demolition and construction. This unique dataset will demonstrate the effectiveness and impact of operational changes to TT, providing crucial information about reduction in concentrations and exposures following cessation of TT. This information will be essential for management of military wastes throughout the U.S. to reduce exposures to chemicals associated with many preventable health conditions.

NIH Research Projects · FY 2025 · 2024-03

Project Summary Inflammatory bowel disorders and necrotizing enterocolitis represent insufficient epithelial repair, stemming from failure of proper maintenance and expansion of resident intestinal stem cells (ISCs). ISCs are housed in invaginations called crypts that expand during development and repair after damage in a process called crypt fission. Little is understood of how crypt fission is mediated, however, signaling factors including BMP inhibitors and non-canonical Wnts are implicated. ISCs are regulated and maintained by similar signaling factors secreted by a surrounding mesenchymal environment called “the niche”. It is unclear what role the niche plays in mediating crypt fission. The niche is composed of a myriad of different cell types, including PDGFRA+ intestinal subepithelial myofibroblasts (ISEMFs) and smooth muscle, that are anatomically, molecularly, and functionally distinct. ISEMFs occur closest to the epithelial-mesenchymal barrier, express both BMPs and non-canonical Wnts; smooth muscle populations occur beneath crypts and express abundant BMP inhibitors. Preliminary data suggests that signaling from both ISEMFs and smooth muscle is required for proper crypt fission. Smooth muscle ablation reduces crypt fission during development; however, functional co-culture assays show limited smooth muscle support of organoid growth in vitro. ISEMFs, on the other hand, promote different organoid co-culture phenotypes depending on level of BMP inhibitor added: in low levels, ISEMFs promote differentiation, and in high levels, promote increased crypt budding, aka fission. My hypothesis is that crypt fission is a process coordinated by the signaling activities of both ISEMFs and smooth muscle. In Aim 1, I will investigate the anatomical and functional profiles of ISEMFs and smooth muscle in crypt fission. I will determine when these cells occur during instances of crypt fission, including postnatal development and repair after damage, test the requirement of ISEMFs in promoting crypt fission in vivo, and sufficiency of ISEMFs and smooth muscle in directing crypt fission in vitro. In Aim 2, I will test whether ISEMFs direct crypt fission via non-canonical Wnt signaling. Using both in vitro and in vivo methods, I will determine the specific function of ISEMFs in directing crypt fission via non-canonical Wnt5a. Together, these studies will provide fundamental insights into the collective regulation of crypt fission via distinct mesenchymal niche populations during development and epithelial repair, aiding our understanding of fundamental intestinal biology and disease.

NIH Research Projects · FY 2026 · 2024-02

ABSTRACT – The North Carolina Center for Coastal Algae, People, and Environment (NC C-CAPE) will combine multidisciplinary expertise in ocean science, toxicology, epidemiology, modeling, and community engagement to understand, predict, and reduce risks to human health from cyanobacterial Harmful Algal Blooms (HABs) in coastal waters. Growing threats to ecosystem and human health are expected with the increasing frequency, intensity, and range of cyanobacterial blooms, attributable to eutrophication. For NC's coastal waters, including US' largest lagoonal estuary, the Pamlico-Albemarle Sound System, concerns about emergent HABs have surged and coincide with reports on cyanobacterial toxin presence, mainly microcystins (MCs), in water and seafood. The transport of toxic algae and MCs along the freshwater-to-marine continuum further increases the potential to spread MC risks across coastal environments. Epidemiological studies measuring the association of MC exposure and liver toxicity, including (Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD), in rodent models are necessary to determine whether chronic MC exposure is associated with liver toxicity, MASLD and liver cancer in humans. Most research and environmental testing have focused on a single MC congener but since blooms are associated with mixtures of congeners that vary in toxicity, further data is needed to understand risks that emerge from MC mixtures and inform human health guidelines. NC C-CAPE will investigate the health effects of various MC mixtures, and elucidate links among environmental drivers and HAB dynamics, MC congener composition, and toxin contamination in oysters and blue crabs. Project 1 will advance our understanding of HAB dynamics and MC contamination in seafood, combining state-of-the-art in situ observing technologies and targeted field surveys. In addition, experimental work will elucidate trophic transfer of toxins in oysters and blue crabs. Project 2 will define how MC mixtures influence mechanisms of liver toxicity and resulting risk of adverse health outcomes in regulatory-relevant mammalian models as well as at- risk human populations. Project 3 will integrate highly diverse data sets and coastal circulation modeling within a probabilistic modeling framework to elucidate environmental controls on MC distribution in water and seafood and assess MC exposure risk. The Center's Community Engagement Core will use the principles of data democracy, where community members are experts with the capacity to conduct critical and systemic inquiry into their own lived experiences, to address HAB exposure and prevention. The Administrative Core will provide effective fiscal and scientific leadership to promote collaborations across all Center components and beyond. As an integrated whole, NC C-CAPE will provide significant insight to guide efforts to implement effective monitoring approaches, inform guideline values for safe consumption of water and seafood, deliver tools to assess toxin exposure risk, and leverage community engagement initiatives to fill data gaps and improve oceans and human health.

NIH Research Projects · FY 2025 · 2024-02

PROJECT SUMMARY: A critical function of the nervous system is to rapidly process sensory information and initiate appropriate behavioral responses. Defects in sensory processing and behavior selection are commonly observed in neuro-psychiatric conditions including anxiety, autism (ASD), and schizophrenia (SZ). Despite the biological and clinical relevance, our understanding of the cellular and molecular mechanisms regulating these processes is limited, in part due to the intricate and dynamic circuitry involved in complex human decision-making. The etiology of sensory processing disorders remains equivocal; however, it is hypothesized that intrinsic/genetic, extrinsic/environmental and the interactions of intrinsic and extrinsic factors can play fundamental roles. Understanding the genetic components of environmental triggered response is critical in understanding the overall impact of the environment on organisms, including humans. Many environmental changes show differential response within populations of individuals due to genetic differences in the affected pathways. In parallel, many environmental pollutants have a range of adverse neuro-health outcomes and despite increasing recognition of the importance of evaluating neurotoxicity in safety assessment, tens of thousands of commercial chemicals in current use, have not been evaluated. In this R21 proposal we investigate how gene by environmental interactions (GxE) impact developmental neurotoxicity linked to sensory processing deficits and neuro-psychiatric conditions later in life. We utilize the Medaka Inbred Kiyosu-Karlsruhe (MIKK) Panel to test the hypothesis that there are common pathways of environmental contaminant response across vertebrates, and that the majority of these pathways have segregating genetic variation contributing to polygenic GxE effects of contaminant responses. The MIKK panel consists of 80 near- isogenic inbred lines, currently inbred for 22 generations, with fully sequenced genomes and transcriptome. Both molecular and organismal phenotypes are distinguishable, and molecular traits can be mapped to specific loci. We propose that the MIKK panel will provide unique insights into GxE components of developmental neurotoxicity and sensory processing behaviors related to neuropsychiatric conditions. Advances in developmental toxicity studies using zebrafish and medaka, key biomedical model species, have provided insights using larval behavioral studies. The high relative fecundity of teleost models, as compared to mice, as well as the regulatory advantages to using an earlier-diverging vertebrate (reducing the use of animals in research) provides additional incentives to developing these methods. The MIKK panel provides a key resource with the isogenic strains necessary to characterize the genomic contributions to environmental effects with important implications for sensitive human populations.

NIH Research Projects · FY 2026 · 2024-02

Project Summary/Abstract Research: Pharmaceuticals modifying intestinal incretin secretion and gluconeogenesis are promising new therapies for obesity and diabetes mellitus, but their mechanisms of action are poorly understood limiting their application. Elevated circulating pools of the essential branched-chain amino acids (BCAAs) and their metabolites are consistently associated with obesity and diabetes with research primarily focused on liver and muscle metabolism of dietary protein without considering intestine amino acid metabolism. Circulating BCAAs in mammals must either originate from the diet or the microbiota residing in the lumen that upregulates its expression of BCAA enzymes in obese and insulin-resistant animal models. The amino acid glutamine provides significant energy to the intestine in fasted and fed states, reducing glucose oxidation by intestine cells but it is not known if BCAAs drive similar metabolic changes. The intestine also metabolizes microbe-produced nutrients like propionate in fasted and fed states for energy and metabolite production. In isolation, microbe-produced nutrients and BCAAs are known to stimulate the secretion of peptide incretin hormones from nutrient sensing cells lining the lumen that coordinate whole body metabolism in preparation for a nutrient load. Incretin response and enteric glucose metabolism are reduced in obese and diabetic patients but the mechanisms driving dysregulation are poorly understood. Synergy between microbe-produced and dietary nutrients could contribute to incretin dysregulation and/or alter enteric metabolic effecting circulating metabolite pools. Directly measuring the metabolism of dietary and circulating BCAAs will quantify the contribution of intestine metabolism to circulating BCAA and metabolite pools. Determining if intestine BCAA metabolism interacts with the metabolism of microbiota-produced nutrients and sucrose will show if intestine metabolism contributes to the elevated BCAA and metabolite pools associated with metabolic disease. Candidate/Training: Long term, I plan to pursue an independent research career managing an interdisciplinary laboratory developing probiotics and/or pharmaceuticals that change intestine nutrient handling to treat metabolic disease. In pursuit of this goal, I have assembled research aims and a mentoring team to provide me with the foundational knowledge and training essential to my progress. Dr. White, an expert metabolic physiologist with many high-profile publications on BCAA metabolism in other tissues, will balance the more microbiology-driven mentorship provided by Dr. John Rawls. We have detailed the technical skills I will gain through their training or formal courses and detailed the community meetings I will attend to build the necessary skills to transition to independence. A larger committee including the directors of Duke’s Metabolic Physiology Institute and Microbiome Center as well as the Chief of the Division of Gastroenterology in the Department of Medicine will monitor my technical and professional progress to ensure adequate support is provided.

NIH Research Projects · FY 2026 · 2024-02

PROJECT SUMMARY Intestinal failure results from conditions such as trauma-related small bowel injury, necrotizing enterocolitis, and inflammatory bowel disease. Treatment options are limited; however, an important emerging therapeutic approach is intestinal transplantation (IT). When successful, IT is associated with marked improvements in quality of life and overall well-being. However, its current success rate is <60% 5 years post-transplant, and there are multiple factors that limit its clinical use. The major impedance to more successful transplants is donor tissues' limited tolerance to current storage methods. The current standard, static cold storage (CS), has been shown to cause epithelial damage after 6 hours (hr) as well as inflammation and loss of epithelial tight junctions. Indeed, clinical studies show that intestinal allograft preservation of >6 hr of cold ischemic time correlates with a progressively higher rate of recipient post-reperfusion syndrome, translocation of enteric bacteria that cause systemic infections, induction of inflammation, and increased transplant failure. Thus, methods that could improve graft viability and organ preservation, especially reducing the incidence and severity of ischemia- reperfusion injury could have a major impact on enhancing the IT success rate, making it the preferred therapy for intestinal failure patients. Normothermic machine perfusion (NMP) has shown promise in clinical heart, lung, and liver transplant scenarios, but this potentially groundbreaking advancement has not been developed for intestinal failure. We have performed highly promising preliminary studies using NMP in porcine and human intestine and have shown compared to CS: 1) Successful allogeneic transplantation with fewer histologic signs of epithelial reperfusion injury, enhanced intestinal stem cell activation, and histologic evidence of active epithelial restitution and regeneration in 6 hr NMP-stored porcine small intestine. 2) Histologically intact epithelial barrier in 6 hr NMP-stored human donor small intestine. We hypothesize that intestinal NMP will reduce ischemia-reperfusion injury by enhancing epithelial barrier integrity and function and decreasing inflammation, thereby minimizing factors that prime the graft for failure. We will use an ex vivo pig intestinal tissue and a porcine model of IT to address the hypothesis with the following specific aims: Aim 1. To determine the extent to which NMP protects epithelial cell integrity and regenerative potential to enhance barrier function. Aim 2. To determine if NMP minimizes allograft inflammatory activation and the cellular mechanisms mediating pro- and anti- inflammatory processes during allograft storage. Aim 3. To determine if NMP enhances the suitability of injured intestine for transplantation. Successful completion of these aims will develop a mechanistic basis to enhance intestinal allograft function by mitigating preservation injury and will address the practical limiting factor of the number of grafts suitable for transplant. This could dramatically expand the applicability of IT to patients with intestinal failure and lead to an enhanced quality of life for these individuals.

NIH Research Projects · FY 2026 · 2024-01

Project Summary Allergic asthma results in predominantly type-2 (Th2) mucoinflammatory responses including granulocytic inflammation and respiratory epithelial remodeling. These features are also consistently observed in the respiratory tract of rodents exposed repetitively to ozone. Therefore, the ozone-predominated air pollution during the resolution phase of allergic asthma may interfere with the restoration of structure and function in the allergic nasal and pulmonary airspaces. Currently, the molecular and cellular level understanding of the pathogenesis and resolution of either ozone- or allergens-induced Th2 mucoinflammatory respiratory responses has significant knowledge gaps. Therefore, detailed studies addressing these knowledge gaps are essential in promoting our understanding of the interference between ozone pollution and the resolution of allergic inflammation in asthma. Our central hypothesis is that IL-33 regulates the pathogenesis of Th2 inflammation in a cell lineage-specific manner and that targeting of IL-33-ST2 axis will mitigate active inflammation and promote the resolution of mucoinflammatory respiratory disease. The overall objective of this proposal is to test the benefit of inhibition of IL33-ST2 signaling during the pathogenesis and resolution of ozone- and allergens-induced respiratory (nasal and lung) inflammation. In aim 1, we will employ cross-genotype bone marrow chimera approach to elucidate the autocrine versus paracrine IL-33 signaling between hematopoietic progenitor cells (HPCs) and non-HPCs during active ozone/allergens-induced respiratory inflammation. In aim 2, we will test our hypothesis that ozone-exposure disrupts the resolution kinetics of allergens-induced respiratory inflammation. In aim 3, we will test the hypothesis that the genetic and pharmacological inhibition of IL-33-ST2 axis neutralizes ozone-mediated disruption in the resolution of allergens-induced respiratory inflammation. The findings from our studies will enhance our mechanistic understanding of the cell lineage- and signaling direction-specific role of the upstream master regulator of ozone/allergens-induced respiratory inflammation. Impact of ozone on the resolution kinetics of allergic inflammation and the potential for the genetic and pharmacological expedition of ozone-disrupted resolution of allergic airway inflammation will have translational impact. Eventually, these findings may be applied towards the development of anti-inflammation and pro-resolution therapeutics against air-pollution induced Th2 inflammatory diseases.

NIH Research Projects · FY 2026 · 2024-01

Project Summary Approximately 33% of the nearly 700 workplace chemicals identified in the National Institute of Occupational Safety and Health (NIOSH) Pocket Guide are associated with hepatotoxicity. Several of these have been linked to increased liver disease mortality in workers in different occupational settings such as heavy construction equipment operators, chimney sweepers, and chemical workers. Xenobiotic-induced hepatotoxicity is characterized by oxidative stress, inflammation, and fibrosis, which, in later stages, may result in hepatic failure and hepatocellular carcinoma (HCC). While transcriptional perturbations have been implicated in inflammation and fibrosis; the role of post-transcriptional regulation in the development of xenobiotic-induced hepatic inflammation and fibrosis is unclear. The tristetraprolin (TTP) family of RNA binding proteins (RBPs) including zinc finger protein 36 (ZFP36) commonly referred to as TTP, zinc finger protein 36 like 1 (ZFP36L1), and zinc finger protein 36 like 2 (ZFP36L2), are the key players in post-transcriptional regulation of a large number of inflammation-relevant mRNAs. These proteins bind to AU-rich elements (AREs) on the 3’untranslated regions (3’UTRs) of target mRNAs and promote their decay. TTP family RBPs are dysregulated in human HCC. Industrial chemicals including chlorpyrifos, tetrachlorodibenzo-p-dioxin (TCDD), and carbon tetrachloride (CCl4), also dysregulate the expression of TTP family RBPs. However, the downstream molecular and cellular effects of these dysregulations on the host remain unknown. In this proposal, we will test our novel hypothesis that xenobiotic-induced dysregulation of TTP family RBPs expression results in altered post-transcriptional regulation that determines the pathogenesis of hepatic inflammation and fibrosis. We will use CCl4-induced liver inflammation and fibrosis as a model of hepatotoxicity and test our hypothesis through three specific aims. In Aim 1, we will employ liver-specific ablations of the three RBPs in mice and novel “omics” approaches to test the pathogenic mechanisms by which these RBPs regulate xenobiotic-induced liver inflammation and fibrosis. Aim 2 will characterize the cellular and molecular mechanisms by which TTP family RBPs regulate epithelial- mesenchymal transition, a lead cause of fibrosis and tumor metastasis, and finally, Aim 3 will test whether increasing the expression of TTP family RBPs in the liver protects against xenobiotic-induced hepatic inflammation and fibrosis. The overall goal of the proposed research is to understand the role of TTP family RBP mediated post-transcriptional regulation in the pathogenesis of xenobiotic-induced hepatotoxicity. Successful completion of the proposed studies will have a significant impact on the mechanistic understanding of the pathophysiology of xenobiotic-induced liver disease and the potential identification of TTP family RBPs as endogenous anti-inflammatory/anti-fibrotic proteins whose activity could be possibly enhanced to delay or prevent the onset of liver failure.

NIH Research Projects · FY 2026 · 2024-01

Black adolescents are disproportionately at risk of negative sexual health outcomes, such as HIV and other sexually transmitted infections (STIs), compared to their peers. Condoms are an effective preventative measure for adolescents, as they are more accessible than other forms of HIV prevention (e.g., pre-exposure prophylaxis) in addition to being the only form of contraceptive that reduces the risk of both STIs and unintended pregnancy. However, condom use among Black adolescents is particularly low, with Black adolescents reporting lower condom use at last intercourse than White and Hispanic adolescents. Black individuals face disparities in care and access influential to their condom use decisions. Adolescent condom use decisions may also be influenced by the rapid biological changes taking place during this developmental period and the navigation of romantic and sexual relationships for the first time. Prior literature has mostly focused on individual-level (i.e., individual attributes) predictors of condom use, finding somewhat conflicting results and neglecting the social, environmental, and contextual predictors influential to condom use for this age group. Thus, the purpose of this study is two-fold: (1) to use meta-analytic methods to systematically review and statistically synthesize the literature surrounding individual-level predictors of condom use for Black adolescents (Aim 1) and (2) to use in-depth individual interviews to address the gaps in prior literature surrounding the role of social, contextual, and environmental factors in condom use among Black adolescents (Aim 2). The proposed study will utilize the Multiple Domain Model of Condom Use, a model outlining both the cognitive decision-making around condom use, as well as the social, environmental, and contextual factors influential to condom use, as a framework to address multilevel predictors of condom use decisions amongst this population. Through conducting this F31 study in coordination with the proposed training activities, the F31 PI will meet the following training goals: 1) gain proficiency in meta-analytic techniques; 2) gain proficiency in qualitative research methods; 3) gain theoretical and empirical knowledge of the health disparities experiences by Black adolescents; 4) develop expertise in adolescent sexual health and behaviors; and 5) build publication record, presentation skills, and professional network through professional development training, all of which will aid in the PI’s goal of becoming an independent researcher.