Pennsylvania State Univ Hershey Med Ctr

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY Murine Polyomavirus (MPyV) is a well-established model system for studying viral assembly, genome packaging, and host interactions. Polyomaviruses are small, non-enveloped double-stranded DNA viruses that can cause disease in mammals, including immunocompromised human hosts. Despite their clinical and biological relevance, fundamental questions remain about how polyomaviruses assemble inside host cells and how structural polymorphism contributes to their replication and immune evasion. Preliminary cryo-electron microscopy (cryo-EM) and charge detection mass spectrometry (CDMS) data from our laboratory reveal that MPyV forms a previously uncharacterized, ordered particle with C3 symmetry, containing 48 VP1 pentamers, double the amount proposed in earlier models of octahedral intermediates. These findings challenge long-standing assumptions about polyomavirus assembly and suggest a level of structural plasticity previously underappreciated. However, it remains unknown how these assemblies form in vivo, whether they correlate with distinct stages of viral replication, and what roles VP2, VP3, and the chromatinized genome play in these processes. This proposal aims to define the molecular architecture and polymorphic assembly pathways of MPyV particles isolated directly from infected mouse cells using an integrated cryo-EM and mass spectrometry approach. We will pursue two specific aims: • Aim 1: Characterize the structural polymorphism of MPyV particles during active replication. We will apply single-particle cryo-EM for resolving ordered structures and use cryo-electron tomography (cryo-ET) for pleomorphic assemblies. CDMS will provide mass profiles to correlate with structural models, enabling a comprehensive view of the polymorphic landscape. • Aim 2: Elucidate the internal architecture of native T=7 MPyV virions. We will investigate the packaging of the double-stranded DNA genome, its organization with host histones into nucleosome-like structures, and the localization and stoichiometry of minor capsid proteins. Our team brings extensive expertise in high-resolution virus structure determination, asymmetric reconstructions, and the integration of cryo-EM with CDMS. We have pioneered structural studies of HBV and other viruses using these approaches. The successful completion of this project will yield the first high-resolution structures of native MuPyV assembly intermediates and infectious virions, providing insights into the principles of viral morphogenesis and informing broader studies of polyomavirus biology and antiviral design.

NIH Research Projects · FY 2026 · 2026-06

Abstract Osteoarthritis (OA) is a debilitating disease of the joints involving progressive cartilage degeneration, with no disease modifying therapy available. therefore, it is important to identify novel molecular pathways that can be targeted for OA drug therapy. Sympathetic innervation and receptors characterize OA joint tissues. Although the importance of sympathetic signaling through AR is characterized in skeletal homeostasis, its cartilage-specific role in OA development and progression is largely unknown. Adrenergic receptors are G protein-coupled receptors, their signaling is regulated by the kinase GRK2. We recently demonstrated a key role for GRK2 in diminishing the homeostatic G-protein signal through receptor desensitization in chondrocytes leading to their pathologic differentiation, cartilage degeneration and OA progression. Importantly, we showed that inhibiting GRK2, by genetic deletion or by inhibitory drugs, reverses this process and recovers the homeostatic G-protein signal. However, specific receptors that are desensitized by GRK2 during OA pathogenesis are unknown. Our preliminary data showed decreased b2-AR expression and signaling in OA human and mouse cartilage, with opposite effects of b2-AR stimulation in early and late OA. Altogether, this supports our overarching hypothesis that b2-AR signaling is altered in OA cartilage through GRK2-mediated desensitization, and that correcting this alteration can be a novel therapeutic strategy for OA. To validate our hypothesis, in the first aim we use genetic and pharmacologic manipulations of AR in chondrocytes of DMM mice at early and late phases of OA to determine its role in OA development and progression. In the second aim, we use similar manipulations to determine the role of GRK2- mediated b2-AR desensitization in OA development and progression in OA mice and study the role of b2-AR resensitization in human normal and OA cartilage. These studies will fill a gap in the literature by defining b2-AR regulatory and signaling changes in the joint cartilage during OA, it will enable us to discover a novel therapeutic strategy and targets for OA.

NIH Research Projects · FY 2026 · 2026-06

Project Summary Innumerable functions have been attributed to the cerebellum: they are as fundamental as movement and as far ranging as social motivation. Underlying these functions are its connections with other brain structures. The most prominent of these is the cerebellothalamocortical pathway. Despite its importance, it is not completely understood how this pathway operates. Preliminary data indicates that burst/tonic modes of the thalamus dynamically regulate this communication. In this proposal we use in vitro and in vivo experiments to build realistic conductances of DCN activity for dynamic clamp of the thalamus, and examine exactly how the thalamus controls cerebellar inputs. This approach allows us to rapidly test many features of cerebellothalamic transmission. We will also record the cerebellum in pathophysiological conditions and impose this activity on the thalamus to specifically examine alterations in pathological states. Here we focus on tremor, which has an established cerebellothalamocortical etiology, and an unambiguous behavioral outcome. We will test this using dynamic clamp, in vivo whole-cell, and multisite single-unit recordings. We will also use CRISPR-mediated knockout of controllers of thalamic excitability to understand cerebellothalamic transmission, and pharmacological strategies to normalize pathological activity. This proposal seeks to understand cerebellothalamocortical communication so that it can be controlled to alleviate any cerebellar dysfunction.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY/ABSTRACT This K23 proposal will address the critical need for evidence-based transdiagnostic sleep interventions for autistic adults. Autistic adults frequently report a multitude of pervasive sleep and circadian problems, including difficulties initiating and maintaining sleep, excessive sleepiness, delayed phase, and irregular sleep– wake schedules. These sleep and circadian problems often occur in unison rather as isolated problems, and contribute to the onset, worsening, and continuation of mental health disorders. This project will adapt and pilot the Transdiagnostic Intervention for Sleep and Circadian Dysfunction (TranS-C), an effective sleep intervention, so that its content and delivery are effective and sustainable for autistic adults. Aim 1 is to iteratively adapt as needed and pilot TranS-C for autistic adults (18-65 yrs). Preliminary data, iterative pilot testing with autistic adults (N=15-24), and input from an advisory panel of autistic adults (N=4), caregivers (N=4), medical providers (N=2), and behavioral health clinicians (N=2) will guide needed adaptations. Assessments for Aim 1 include multidimensional sleep health (MSH) (actigraphy, self-report measures), as well as implementation science outcomes (feasibility, acceptability, engagement, and fidelity). Aim 2 is to conduct a pilot randomized trial of the adapted TranS-C to examine intervention efficacy, as well as feasibility, acceptability, engagement and fidelity. Autistic adults (18-65 yrs) (N=90) will be randomly assigned to the adapted TranS-C, traditional TranS-C, or a wait-list control, with assessments of multidimensional sleep health (MSH) (actigraphy, self-report measures), as well as self-report measures of social, emotional, and cognitive functioning, at pretreatment, posttreatment, and 3-month follow-up. Aim 3 is to evaluate hypothesized mediational processes that may explain relationship between sleep and circadian problems and social, emotional, and cognitive functioning in autistic adults. The proposed research and the career development plan will support Dr. Lenker’s training goals to acquire skills and knowledge in: (1) qualitative and mixed methods for intervention adaptation and development; (2) conduct of clinical trials, especially for TranS-C and Autism; and (3) the application of implementation science methods and frameworks to clinical sleep research. The resources and expertise of the assembled team of interdisciplinary mentors will provide an outstanding context to propel Dr. Lenker’s career. This project will also provide necessary data for Dr. Lenker’s future R01 submission of a large-scale effectiveness-implementation trial of a transdiagnostic sleep intervention trial. This project aligns with NICHD’s priorities, as it focuses on the complexity of co-occurring conditions such as sleep and circadian problems for autistic adults within a multidimensional and transdiagnostic context, as well as the development of effective patient-centered treatment options for autistic adults utilizing implementation science frameworks.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY Diabetic retinopathy (DR) is a significant ocular complication caused by diabetes and a leading cause of blindness. The current standard of care for DR is based on the intraocular delivery of antibodies that block action of the pro-angiogenic cytokine vascular endothelial growth factor (VEGF), but this approach only sustains clinically significant improvement in visual acuity in a minority of patients. Presently, there is an unmet clinical need for therapeutic strategies that are preventative and/or provide interventions early in the preclinical and non- proliferative stages of DR by targeting the underlying molecular events that cause retinal dysfunction. The studies here are significant because they are designed to broaden our understanding of the systemic molecular events that contribute to DR pathogenesis. It is well-accepted that the severity of vision loss in people with diabetes is strongly associated with a reduction in kidney function. This association is attributed to common molecular mechanisms that are responsible for damage to the inner blood-retinal barrier and renal glomerulus. In support of that idea, we recently demonstrated a critical role for the stress response protein REDD1 (Regulated in Development and DNA damage 1) in both visual function deficits and renal injury in diabetic mice. This R21 Exploratory/Developmental Research Grant is based on an unexpected discovery that we made in mice with kidney-specific REDD1 deletion. Surprisingly, kidney-specific REDD1 deletion prevented diabetes-induced functional deficits in the retina, as well as in the kidney. The studies herein are highly innovative as they potentially reframe the relationship between diabetic nephropathy and DR. Currently, our understanding of DR attributes neurovascular damage to biochemical changes that take place locally within cells of the retina due to a rise in blood glucose concentrations. The concept that signaling events localized to the kidneys are necessary for the development of retinal complications caused by diabetes would represent a paradigm shift in the field. The studies here will test the central hypothesis that maladaptive signaling events in kidney podocytes are necessary for diabetes-induced retinal complications. While podocytes are classically known for their role in glomerular filtration, more recent work has revealed immunomodulatory roles in antigen presentation, expression of co- stimulatory molecules, and T cell activation. To our knowledge, the impact of podocyte immunomodulation on DR has never been explored. Aim 1 will build on the promising preliminary data by further characterizing the retino-protective effect of podocyte-specific REDD1 deletion in diabetic mice. Aim 2 will then examine the relationship between renal and retinal damage caused by diabetes by employing an alternative model of diabetes-induced renal protection and a surgical model of renal injury. Finally, Aim 3 will explore the role of podocyte-dependent T cell homeostatic changes in the development of diabetes-induced retinal complications. This project is clinically significant because it will help to support novel therapeutic strategies for DR that address both retinal neurovascular damage and molecular events localized to renal podocytes.

NIH Research Projects · FY 2026 · 2026-06

Project Summary/Abstract Substance use disorder incurs a massive toll on individual and economic health, costing the United States billions of dollars every year and thousands of lost lives due to fatal overdose. In recent years, this has been driven by potent synthetic opioids such as fentanyl in the illicit drug supply, alongside an increased prevalence of opioid use disorder in females, necessitating improved understanding of the neural mechanisms that promote fentanyl misuse across sex. A growing body of clinical and preclinical work implicates maladaptive signaling in the prelimbic cortex (PL) and its reciprocal connections to reward centers in driving drug seeking behavior. However, this work has been largely restricted to non-opioid drugs and male subjects, limiting our understanding of whether these mechanisms extend to fentanyl misuse or to females. My preliminary experiments in both sexes indicate dopaminergic signaling in PL drives fentanyl-context memories. The goal of this study is to expand this line of research to the more translationally relevant self-administration paradigm to interrogate the role of PL circuits in fentanyl relapse. In this study I aim to identify the PL inputs and outputs that promote fentanyl relapse. The overarching hypothesis is that fentanyl relapse is dependent on dopaminergic input from ventral tegmental area (VTA) to PL and downstream PL projections to the nucleus accumbens (NAc). In Aim 1, I will identify the role of dopaminoceptive PL neurons in fentanyl relapse across sex. I will learn to use cell-type- and projection-specific chemogenetics to bidirectionally manipulate activity of dopaminoceptive PL neurons, and their downstream terminals in the NAc, during both non-reinforced seeking and fentanyl-induced reinstatement. In Aim 2, I will determine the necessity of VTA dopaminergic input to PL in fentanyl seeking. I will learn to use in vivo imaging techniques to demonstrate that dopamine release in PL differentially encodes fentanyl seeking versus natural reward. Then I will use a dual- recombinase strategy to specifically inhibit dopaminergic input to PL and attenuate fentanyl seeking. Together, these experiments will provide novel insights into the sex-specific neural mechanisms of fentanyl use and relapse which may translate to other abused substances and inform future development of addiction therapeutics.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY/ABSTRACT This proposal will address the critical need for evidence-based transdiagnostic sleep interventions for autistic adolescents and young adults (AYA). Autistic AYA frequently report a multitude of pervasive sleep and circadian problems, including difficulties initiating and maintaining sleep, excessive sleepiness, delayed phase, and irregular sleep–wake schedules. These sleep and circadian problems often occur in unison rather as isolated problems, and contribute to the onset, worsening, and continuation of mental health disorders. This project will adapt and pilot the Transdiagnostic Intervention for Sleep and Circadian Dysfunction (TranS-C), an effective sleep intervention, so that its content and delivery are effective and sustainable for autistic AYA. Aim 1 is to iteratively adapt as needed and pilot TranS-C for autistic AYA (12-25 yrs). Preliminary data, iterative pilot testing with autistic AYA (N=15-24), and input from an advisory panel of autistic AYA (N=4), caregivers (N=4), medical providers (N=2), and behavioral health clinicians (N=2) will guide needed adaptations. Assessments for Aim 1 include multidimensional sleep health (MSH) (actigraphy, self-report measures), as well as implementation science outcomes (feasibility, acceptability, engagement, and fidelity). Aim 2 is to conduct a pilot randomized trial of the adapted TranS-C to examine intervention efficacy, as well as feasibility, acceptability, engagement and fidelity. Autistic AYA (12-25 yrs) (N=90) will be randomly assigned to the adapted TranS-C, traditional TranS-C, or a wait-list control, with assessments of multidimensional sleep health (MSH) (actigraphy, self-report measures), as well as self-report measures of anxiety, depression, emotion regulation, social functioning, and suicidal ideation and behavior, at pretreatment, posttreatment, and 3-month follow-up. Aim 3 is to evaluate hypothesized mediational processes that may explain relationship between sleep and circadian problems and mental health outcomes in autistic AYA. The resources and expertise of the assembled research team of interdisciplinary researchers will provide an outstanding context to successfully execute this project. This project will also provide necessary data for Dr. Lenker’s future R01 submission of a large-scale effectiveness trial of a transdiagnostic sleep intervention trial for autistic AYA. This project aligns with NIMH’s priorities, as it focuses on assessing and treating sleep and circadian problems within a multidimensional and transdiagnostic context to better understand underlying mechanisms related to mental health, as well as optimizing patient-centered treatment options for autistic individuals.

NIH Research Projects · FY 2026 · 2026-05

Desmosomes and adherens junctions (AJs) are adhesive intercellular junctions that are essential for development of the epidermis and for the maintenance of cell-cell adhesion in adults. A variety of autoimmune and genetic skin diseases highlight the importance of adhesive junctions in various aspects of epidermal integrity and skin inflammation. Darier disease is an epidermal fragility and inflammatory disorder characterized by loss of desmosome function but caused by mutations in the ATP2A2 gene encoding an endoplasmic reticulum (ER) Ca2+ pump, SERCA2b. In the previous funding cycle, we discovered that desmosomes are intimately associated with peripheral ER tubules. These findings raise the possibility that a functional and physical relationship between ER and desmosomes underlies the pathomechanisms of skin disorders characterized by adhesion or differentiation defects. We propose a new model for keratinocyte cell junction organization in which the AJs, desmosomes and ER form a multijunctional organelle complex that integrates adhesion and membrane physiology. We hypothesize that AJs recruit ER to the cell periphery to initiate desmosome formation and plasma membrane remodeling, and that these processes are perturbed when adhesive junctions are compromised. Aim 1 studies will determine how AJs recruit ER to cell- cell contacts to modulate keratinocyte membrane physiology and how the adhesion-organelle complex is organized in epidermis. Aim 2 studies will determine the function of ER in desmosome assembly and how this process is perturbed in models of genetic skin disorders such as Darier. High resolution live-cell imaging and biochemical approaches will be used to determine how desmosome formation occurs at the tips of ER tubules and how this process is coordinated with the formation of lipid raft membrane domains that cluster desmosomal proteins to form nascent adhesive junctions. The results will form a new foundation for understanding the basic mechanisms of cell junction formation, how the ER is spatially and functionally integrated with cell adhesion, and how these processes are perturbed in skin diseases characterized by desmosome dysfunction.

NIH Research Projects · FY 2026 · 2026-05

Project Summary / Abstract Substance use and addiction remain critical public health challenges, driving preventable deaths and health disparities across the United States. To address the urgent need for evidence-based addiction care, the Penn State Addiction Conference serves as a translational platform to advance research and accelerate the integration of addiction science into practice and policy. As Pennsylvania’s land-grant, R1 institution with multiple campuses across the state, Penn State is uniquely positioned to convene researchers, clinicians, policymakers and community leaders and members across disciplines, sectors and experiences. The conference’s broad, long-term objective is to reduce the burden of substance use and addiction by promoting scientific discoveries and the use of scientific knowledge in prevention, treatment, and recovery strategies. The specific aims are to: (1) advance addiction science by fostering dialogue across the translational research spectrum, with input from multi-sector partners; (2) advance clinical practice by providing continuing education on emerging, evidence-based prevention and treatment strategies; and (3) strengthen implementation by building collaborative networks that support the dissemination of research-informed innovations. The conference design includes a combination of plenary sessions, research presentations, panel discussions, workshops, and networking forums delivered in a hybrid format over two days. Invited speakers will include content experts, from investigators, through clinicians to people with lived experience, to ensure representation of broad perspectives across the addiction field. Efforts will be made to engage trainees, early-stage professionals, and community partners. The program will emphasize interactive formats and cross-sector engagement to enhance learning and stimulate collaboration. Through this multi-pronged approach, the conference will contribute to the National Institute on Drug Abuse’s mission by accelerating the translation of research into strategies that improve health outcomes, reduce the impact of addiction, and promote recovery across communities.

NIH Research Projects · FY 2026 · 2026-04

An Assay for Paenibacillus Detection in Low Resourced Settings We recently identified a novel bacterial pathogen, Paenibacillus thiaminolyticus, from neonatal sepsis patients in Sub-Saharan Africa. The pathogen is highly selective for neonates, neurotropic and extremely lethal, resulting in a syndrome we have termed paenibacilliosis. The pathogen affects thousands of infants in Uganda, Kenya and Zambia and, since our initial identification of the organism in 2020, multiple cases have been reported in the US with equally poor outcomes for infected neonates. The pathogen carries resistance genes to antibiotics used as first line treatment of septic neonates and its rapid migration to the infant’s brain, often within the first few days of infection, renders it further resistant to standard therapy. We have obtained anecdotal evidence that, while standard antibiotic therapy has little impact on attenuating the disease, early intervention with tailored antibiotic therapy in cases of Paenibacillus infection can mitigate some of the more devastating sequelae of the infection. Accordingly, early detection can have a significant therapeutic benefit for patients. As one approach to early and rapid detection of the bacteria that would be suitable for low resourced areas, we propose to develop and deploy a lateral flow device for point-of-care detection of the bacteria in neonatal sepsis cases. The device is based on a collection of monoclonal antibodies we have generated and characterized that are specific for the pathogenic strains of the bacteria. Aim I of the project focuses on development and initial testing of the device. We have contracted with RayBiotech to develop a prototype lateral flow device based on purified monoclonal antibodies we will provide them. We will validate the prototype in house with purified bacteria and existing clinical samples. In Aim 2, we will field test the device with samples from the Jinja Regional Referral Hospital in Uganda obtained by our collaborators in the neonatal infectious disease clinic. These studies will allow us to determine the specificity, sensitivity and selectivity of the device, compared to the gold standard of qPCR detection. The availability of such a device would accelerate effective and appropriate therapeutic intervention in neonatal clinics, particularly in under resourced areas in sub-Saharan Africa. Moreover, the assay would potentiate a variety of follow-up studies, including clinical trials to optimize antibiotic regimens for effective treatment of paenibacilliosis as well as studies aimed at identification of the source(s) of the infection in the environment of the patient’s home as an initial step of implementing preventative measures. These studies have the potential to significantly reduce neonatal morbidity and mortality from sepsis and reduce the health care burden in this challenging environment.

NIH Research Projects · FY 2026 · 2026-04

Human papillomaviruses (HPVs) are responsible for approximately 5% of all human cancers. Four vaccines have been approved for the prevention of cervical and oropharyngeal cancer. However, these vaccines offer no therapeutic benefit for preexisting infections. Infected mothers can transmit HPV to offspring through vertical transmission, either periconceptually, prenatally, perinatally, or neonatally. Recurrent respiratory papillomatosis (RRP), an aggressive and chronic disease in young children, is associated with the vertical transmission of low-risk HPV to infants. Currently, there is no cure, only invasive and repeated surgery. Novel interventions are highly desired for the prevention and treatment of RRP. Due in part to the species-specific and tissue-specific features of HPV, a mouse papillomavirus (MmuPV1) model that recapitulates some features of RRP has only recently been established. As one of the groups that have developed unique reagents and assays to monitoring MmuPV1 infections, we propose to test two novel hypotheses in the current proposal: 1) vertical PV transmission from infected mothers to babies is associated with the time of pregnancy and host immune status of the babies; 2) passive immunization with both polyclonal (pAb) and monoclonal (mAb) neutralizing antibodies can provide protection against oral infections in babies in a dose and time-dependent manner. Our hypotheses are built on both published and unpublished findings, including: 1) Passive immunization with anti- L1 sera can effectively block subsequent infections; 2) Among a panel of in-house mAbs raised against MmuPV1 L1, MPV.A4 can block MmuPV1 infection at both cutaneous and mucosal tissues; and 3) Vaginally infected mothers can transmit MmuPV1 to the oral cavity of offspring in Rag1ko mice. Two specific aims are proposed to test these hypotheses 1) Characterize vertical transmission by testing infected females and fetus at day 0, 7, 14 and 21 post vaginal plug formation after breeding naïve males for viral quantitation; 2) Determine the protection by passive immunization with mAb (MPV.A4) or pAb (anti-L1 sera) at day 0, 7, 14 post vaginal plug formation and monitoring oral infection in babies up to 24 weeks post-delivery. NU/J heterozygous (Foxn1nu/+) females which show detectable infections and advanced diseases at the genital tract after infection will be bred with naïve NU/J homozygous (Foxn1nu/nu) males. At the conclusion of the proposed study, we should have determined when vertical transmission occurs and whether host immune backgrounds are associated with susceptibility to vertical transmission. We will also have determined whether passive immunization with pAb and/or mAb can effectively block papillomavirus infection in babies and if it is time and dose dependent, as well as whether sex-associated protection exists, as we reported previously. An additional key opportunity with this model is that we can assess the effects of passive immunization on both clinical and subclinical PV diseases. Our study will be the first to compare both pAb and mAb against viral transmission in vivo and to determine whether sex and immune backgrounds play a role in passive immunization.

NIH Research Projects · FY 2026 · 2026-04

Project Summary My research aims to elucidate the molecular mechanisms by which surfactant protein-A (SP-A) variants regulate innate immune responses in the lung microenvironment, with the long-term goal of developing novel therapies for acute and chronic lung diseases. Respiratory Syncytial Virus (RSV) is the leading cause of viral mortality in children worldwide. Despite the availability of recent vaccines, uptake remains low, and ~8% of vaccinated children still develop severe disease. Age at initial infection is an independent risk factor for RSV severity, yet the mechanisms driving increased susceptibility remain unclear. RSV severity varies due to complex interactions between the virus and host immune responses, underscoring the need to understand the heterogeneity of host immune responses to develop effective therapies. SP-A, a C-type lectin critical for lung innate immunity, has been implicated in RSV pathogenesis with our previous findings linking young age and the SFTPA2-1A0 variant to severe RSV in children. While SP-A enhances RSV clearance, its precise antiviral mechanisms remain unknown. Toll-like receptors (TLRs), key mediators of innate immunity, are modulated by both SP-A and RSV, suggesting a link between SP-A, TLR signaling, and RSV pathogenesis. Our preliminary data show that neonatal SFTPA2-1A0 mice exhibit a diminished antiviral response compared to wild-type mice in bulk RNA studies, while SP-A attenuates RSV-induced TLR expression in epithelial (A549) cells, and the 1A0 variant has reduced RSV-binding affinity. Based on these strong preliminary findings, we hypothesize that RSV severity in children with the 1A0 variant results from impaired modulation of TLR pathways, leading to delayed viral clearance and excessive inflammation, which can be restored by exogenous SP-A. However, bulk studies fail to capture the complexity of the host immune response to RSV. To address this gap, we will use single-cell RNA sequencing and spatial transcriptomics to delineate the heterogeneity of host immune responses in infected versus bystander cells and generate a high-resolution, unbiased, spatially resolved gene expression map of neonatal lungs (Aim 1), while Aim 2 will elucidate the mechanism of SP-A-mediated TLR regulation in RSV pathogenesis through binding and endocytic assays, advanced imaging, and siRNA/CRISPR approaches in epithelial cells, clarifying how the SFTPA2-1A0 variant affects these processes. These studies will provide a mechanistic understanding of the association between SP-A genetic variants and RSV severity, laying the foundation for future research, including an R01 application, to develop and test personalized, variant-specific therapies for RSV infection. Importantly, this proposal will uncover fundamental aspects of SP-A-mediated regulation of TLR signaling, which may also be relevant to other respiratory viral infections, addressing the broader threat of emerging viral pandemics.

NIH Research Projects · FY 2026 · 2026-03

Abstract No curative therapy exists for ulcerative colitis (UC) due to a critical gap in knowledge regarding the mechanism(s) driving chronic inflammation in UC. The rationale for this proposal is built upon emerging evidence that (1) CD90+ mesenchymal cells, known as myo-/fibroblasts (MFs), are critical to the pathophysiology of UC, although this has not been studied extensively; (2) JAK/STAT signaling is among the key pathways that drive inflammation in IBD; (3) microbiota/stem cell interplay is suggested to be a potential avenue for therapeutic improvement of inflammatory diseases. An increase in pathological type 2 and 17 immune responses by CD4+T and NKT cells, together with abnormal interferon (IFN) signaling, is a hallmark of the inflammation in UC. Our published and preliminary data show that, under gut homeostasis, MFs act as major immunosuppressors of T/NKT cell responses. By contrast, an increase in the inflammatory population of MFs occurs in UC (UC-MFs), supporting pathological T/NKT responses in UC. Thus, we propose that MFs are among the key cells in the pathogenesis of UC. However, the mechanisms responsible for the generation/activation of inflammatory UC-MFs are unknown. We reported that abnormal differentiation of mesenchymal stem cells (MSCs) to MFs occurs in UC. Our preliminary data demonstrated an increase in JAK2 expression and activity in the population of inflammatory MFs in UC. Our initial data suggest that this abnormally high Jak2 activity is key to the pathological responses of UC-MFs and that upregulation of JAK2 expression in UC-MFs is likely to occur during differentiation from tissue-resident MSCs in response to the dysbiotic microbial ligands. MSC therapy has shown promise for treatment of moderate-to-severe UC, but about 50% of patients relapse within the first five years post therapy; the cause of this relapse is unknown. We found that depletion of dysbiotic microbiota prior to MSC treatment shows improved outcome in a preclinical animal model of UC. Thus, we hypothesize that overexpression of JAK2 is key to the pathological activation of UC-MFs, that MyD88-dependent activation of MF progenitors (MSCs) by dysbiotic microbial ligands is a critical event in the generation of Jak2high UC- MFs, and these processes have potential as therapeutic targets. Three specific aims are proposed: (1) Define mechanism(s) by which overexpression of JAK2 contributes to the inflammatory activation of MFs in UC.; (2) Define the role of microbial ligand-dependent MyD88 signaling in the mechanism(s) of upregulation of JAK2 expression within progenitors of MFs and the generation of Jak2high UC-MFs; (3) Evaluate how microbial dysbiosis impacts MSC therapy effectiveness and MSC-mediated replacement of Jak2high UC-MFs in preclinical animal models of UC. We expect to define the novel mechanisms contributing to the pathological activation of mesenchymal cells in UC and to provide a scientific, preclinical basis for the development of specific pathway-mediated, combined mesenchymal cell/microbiota therapeutic approaches.

NIH Research Projects · FY 2026 · 2026-03

ABSTRACT Individuals with post-traumatic stress disorder (PTSD) experience chronic pain at significantly greater rates than the general population and greater pain intensity than those with chronic pain alone. Those with PTSD featuring comorbid pain suffer from higher rates of anxiety, depression, and opioid use disorder than those with just one of the conditions. Furthermore, trauma has been shown to enhance and prolong pain following injury. Clinical imaging studies and preclinical investigation reveal an overlap in the pathologic central nervous system changes that occur in PTSD and the transition from acute to chronic pain. Central to these changes is the nucleus accumbens (NAc), with both PTSD and chronic pain evidencing altered glutamatergic and midbrain monoaminergic afferent inputs to the NAc. Such findings suggest that the increased rate and severity of chronic pain among individuals with PTSD are due to trauma-induced neuroplastic changes in the NAc facilitating increased pain sensitivity. Accordingly, therapies that enhance neuroplasticity in the NAc may provide therapeutic benefits in chronic pain comorbid with PTSD by attenuating trauma-induced changes. We intend to test the therapeutic efficacy of the neuroplasticity-enhancing agent, psilocybin, in an animal model of trauma- induced anxiety and hyperalgesia using a well-established animal model of PTSD. We hypothesize that the psilocybin intervention will attenuate pain and anxiety symptoms by mitigating trauma-induced changes in the NAc via the same mechanism of enhancing oxytocin-mediated neuroplasticity in the NAc by which psilocybin improves social reward learning. We will gather translationally relevant preclinical evidence on this hypothesis with a rat model of traumatic injury, which couples a thermal burn injury model with the procedure known as single prolonged stress (SPS), wherein rats are exposed to three stressors in a single session: immobilization, group forced swim, and ether exposure. SPS is the favored preclinical PTSD model due to its capacity to reliably induce a phenotype that satisfies all DSM-5 and model validity criteria. Critically, SPS on its own also induces pain sensitivity in rats. The therapeutic efficacy of psilocybin intervention will be evaluated using well-defined behavioral assays of anxiety and pain sensitivity, and psilocybin-induced NAc molecular changes will be assessed by qPCR. Using a chemogenetic approach, we will test whether oxytocinergic projections from the paraventricular nucleus (PVN) to the NAc are required for psilocybin’s therapeutic efficacy in this model and how such inputs modulate psilocybin-induced changes in the expression of neuroplasticity and neuromodulator- related genes in the NAc. This project will provide translational evidence of the therapeutic mechanism of psilocybin for PTSD and comorbid pain. Such data will enhance our understanding of the treatment of PTSD and its comorbidities and may aid in the design of novel therapeutic compounds and approaches for this debilitating pathology currently suffering from inadequate treatment options.

NIH Research Projects · FY 2026 · 2026-02

Project Summary The stereocilia of inner ear hair cells are parallel actin bundle based protrusions that must be precisely formed from microvilli structures during development and maintained throughout a lifetime to allow for normal hearing and vestibular function. The stereocilia form a staircase pattern with precise length and width required for normal function in mechanotransduction. Class III myosins (MYO3A and MYO3B) are crucial for forming proper stereocilia length and width, while mutations in MYO3A lead to delayed onset deafness and stereocilia degeneration. The knockout of both MYO3A and MYO3B leads to long and thin stereocilia and profound deafness in a mouse model. We propose that MYO3A is essential because it functions as a tension sensor at the tips of actin protrusions, which is crucial for mediating the balance of forces that govern stereocilia length regulation. We also proposed that MYO3B can only partially compensate for the lack of MYO3A because it lacks specific motor properties, such as the ability to change its motor properties in response to assistive and resistive loads. Indeed, our preliminary data suggests MYO3A has a unique load sensitivity different from any other myosin characterized to date. In addition, our preliminary data and published studies demonstrate that MYO3A can regulate a dynamic population of actin at the stereocilia tips, which we call tip filaments. MYO3A may stabilize the tip filaments which is crucial for the stereocilia widening process. In Aim 1 we will investigate the key differences between MYO3A and MYO3B motors at the biochemical and biophysical level to determine mechanistically why MYO3B cannot compensate of the loss of functional MYO3A. Thus, ensemble and single molecule biophysical studies will characterize the most important mechanical properties of MYO3A&B. In Aim 2 we will investigate the impact of deafness-associated mutations in MYO3A motor domain, which will lay the foundation for understanding the key aspects of MYO3A motor function required for its function in stereocilia. In Aim 3 we will investigate the impact of MYO3B and MYO3A deafness mutations on stereocilia length, width, and tip filament actin turnover. We will also investigate the role of MYO3A binding partners, ESPIN and MORN4, in mediating the stability of the tip filaments and stereocilia length/width. Overall, our comprehensive approach will reveal novel insights into MYO3A function in actin protrusions and lay the foundation for the development of therapies to treat inner ear hair cell stereocilia degeneration.

NIH Research Projects · FY 2026 · 2026-02

PROJECT SUMMARY The lower jaw evolved as a structure composed of many bones the largest of which, the dentary, persists as a single lower jawbone in modern mammals, and is referred to as the mandible in humans. Mandibular disorders, often resulting in small jaws, are among the most common human birth defects. These disorders can dramatically affect quality of life, and are often associated, or compound problems with airway obstruction, speech, and feeding. During embryogenesis, development of the mandible is preceded by and associated with a tubular cartilage rod called Meckel's cartilage (MC) and anomalies of MC have been associated with mandibular disorders. Development of MC in modern mammals is complex: the anterior part contributes to the formation of the mandibular symphysis, its posterior part forms cartilages that mineralize endochondrally to form two middle ear bones, and the posterior half of the middle region forms ligaments. Less is known about the anterior half of the middle region of MC, which is transient, present during a small window of embryonic development before it disappears. Established assessments describe MC as a template for the formation of the mandible, but evidence of this is lacking and little is known of the relationship between the midportion of MC and mandibular mineralization, size, and shape or the processes of MC growth in length, perichondrial ossification, and disappearance of MC. We present data demonstrating that MC does not serve as a template in the way cartilaginous models function in endochondral ossification and hypothesize a new role for the mid portion of MC in determining mandibular length, mineralization of the perichondrium, mineralization of the mandible, and its disappearance. Because our findings challenge the traditional role of MC, we have designed this project to validate the developmental events that take place as the midportion of MC disappears and the mandible forms through a detailed analysis of four processes: 1) initiation and growth in length of MC; 2) mineralization of MC perichondrium; 3) mineralization of the mandible; and 4) disappearance of MC. Our approach is based on knowledge we have gained through preliminary investigations of these processes occurring at different times along the length of MC, and spanning the buccal to lingual aspects of the interior of MC. We couple 3D imaging with tissue and cellular analyses of embryonic mutant Sox9flox/flox;Col2a1-CreERT, and Sox9flox/flox mice to precisely define the changing cellular dynamics of the lower jaw in developmental time and anatomical space. These data are used in turn to inform our RNA-seq analyses of the developing MC and mandible directed at recovering the underlying transcriptome by differential gene expression, pathway, and network analyses. We plan cell lineage tracing experiments to determine the fate of cells from the intermediate region of MC, those that initiate MC perichondrial mineralization, and mandible mineralization. Our integrative approach is designed to bring new understanding to lower jaw development and open novel research areas to advance strategies for bone repair, regeneration, and prevention in mandibular disease.

NIH Research Projects · FY 2025 · 2025-12

Abstract JC polyomavirus (JCPyV) is the causative agent of the often-fatal demyelinating brain disease Progressive multifocal leukoencephalopathy (PML). While 70-90% of adults carry JCPyV lifelong, only after immunosuppression is the virus able to travel from the primary infection reservoir in the urinary tract to the central nervous system. How the virus traffics to and enters the brain is unknown. Utilizing the mouse polyomavirus (MuPyV), a natural mouse pathogen, I have employed Fluorescence-activated cell sorting (FACS), RT-qPCR, flow cytometry, and immunofluorescent imaging to phenotype a subset of macrophages with activity replicating MuPyV. These macrophages are express CD13 and are found in the spleen, brain, and blood. These CD13+ myeloid cells possess unique expression of surface markers compared to other macrophages in the tissues. Notably, CD13- macrophages do not support MuPyV infection. Our published data suggests that the ependyma, a multi-ciliated single-cell layer lining the cerebral ventricles, may be a site of entry into the brain parenchyma. Our lab has found that the ependyma supports productive MuPyV infection. The ependyma is contiguous with the choroid plexus epithelium, which supports JCPyV infection. By immunofluorescence microscopy, I visualized CD13+ macrophages at the ependyma in uninfected mice. Monocytes/macrophages enter at this blood-CSF barrier as part of cell population homeostasis. I have found that CD13+ monocytes also selectively support MuPyV infection. These results together suggest that CD13+ macrophages are a candidate for MuPyV trafficking to the central nervous system.

NIH Research Projects · FY 2025 · 2025-12

ABSTRACT/PROJECT SUMMARY Anxiety is one of the most common and debilitating comorbidities with ADHD, affecting 57% of youth and 84% of adults, with particularly high rates in girls and women. Despite its widespread prevalence, this co-occurrence is often overlooked and poorly understood, contributing to worse mental health outcomes and greater economic costs than either condition alone. Social processes (i.e., social cognitions and relationships) appear to contribute to the emergence of anxiety in youth with ADHD, but extant work has most often relied on mother-reports in community samples, lacking a multi-informant perspective and consideration of how ADHD and anxiety co-occur across development or in clinical populations. These gaps hinder our ability to provide effective, timely interventions, leaving those at highest risk—especially girls and women—without the necessary support. There is also a notable lack of research on girls and women with ADHD and potential sex differences, despite growing identification of ADHD in girls and women, many of whom are identified with anxiety prior to diagnosis of ADHD. Aligned with Goal 2 of the NIH Strategic Plan (Examine Mental Illness Trajectories Across the Lifespan), this project will address these gaps using three existing datasets with large samples of girls and women. Aim 1 will use ongoing clinical cohort data from a specialized lifespan ADHD clinic to identify developmentally relevant social processes in the co-occurrence of ADHD and anxiety in children and adults, utilizing one of the most well- characterized and ecologically valid samples of girls and women with ADHD to date. Aim 2 will use data from two completed studies and one ongoing study to examine electroencephalography (EEG) measures of social processing as markers of ADHD and anxiety, as well as sex differences, in adolescents—a critical period for anxiety onset and heightened social sensitivity, particularly in girls. Findings will provide developmentally and sex-specific insights into altered social processing as a mechanism for co-occurring ADHD and anxiety, along with neural biomarkers during a critical risk period. With mentorship from experts in lifespan ADHD and sex differences (Babinski), EEG methods for assessing anxiety risk (Pérez-Edgar), measurement-based ADHD care in clinical settings (Waschbusch), and translational analytics/bioinformatics in clinical data (Tuan), this project is designed with an integrated training plan to provide the applicant with real-world clinical research experience, focusing on advanced data analytics to how altered social processing contributes to co-occurring ADHD and anxiety across the lifespan, alongside innovative EEG methods to identify neural markers of these processes. The exceptional mentorship team, coupled with the resources and infrastructure at Penn State College of Medicine, offers the optimal environment to support the applicant’s training goals, foster professional development, and promote growth as an independent ADHD researcher focused on identifying developmentally and sex-specific comorbidity risks in ecologically valid populations across development.

NIH Research Projects · FY 2025 · 2025-09

Project Summary/Abstract Alcohol and nicotine are two of the most commonly co-used substances. When used in combination, negative health outcomes, including rates of several cancers, increase substantially. Compounding this issue is the growing popularity of nicotine vapor products such as e-cigarettes. One area that has been receiving increased attention in recent years is the role that neuroimmune function plays in substance abuse. It has been shown that alcohol intake increases neuroimmune activation, particularly at specific subtypes of toll-like receptors (TLRs). Moreover, activation of these receptors increases alcohol self-administration, creating a feedback loop. Interestingly, nicotine in the brain has been shown to be anti-inflammatory. As such, we hypothesize that it is this modulation of neuroimmune function that may be crucial in supporting combined alcohol and nicotine dependence. That is, individuals smoke in order to combat the central negative effects of continual alcohol intake (which through this process supports itself). To do so, experiments in each Aim utilize a cutting edge, custom designed nicotine vapor + liquid alcohol delivery system, giving rats the opportunity to self-administer nicotine vapor for inhalation and liquid alcohol for oral consumption, constituting the most translational model for the use of both drugs to date. The experiments in Aim 1 will assess the effects of long-term alcohol, nicotine, and alcohol+nicotine self-administration on expression of neuroimmune markers in rat brain. Moreover, experiments in Aim 1 seek to understand the impact of individual differences and sex differences in self- administration of these drugs on their own, how preference changes when rats have co-access, and how these differences correlate with changes in neuroimmune signaling. Experiments in Aim 2 seek to understand the effects of activating the neuroimmune system in nucleus accumbens core with a TLR3 agonist or a nicotinic α7 agonist on self-administration. Finally, experiments in Aim 3 will assess the effects of genetic manipulation of prefrontal cortical projections to the nucleus accumbens core on self-administration as this PI has previously shown these projections to play an important role in nicotine+alcohol drug sensitivity. Together, these Aims will give a more complete understanding of the role that neuroimmune function, in particular the intersecting roles of TLR3 and α7 in modulating alcohol and nicotine co-use and may lead to the development of more effective therapeutics.

NIH Research Projects · FY 2025 · 2025-09

Approximately 8.75 million Native Americans (NA) reside in the United States and approximately 10.2% are over the age of 65.1,2 NA elders experience higher health burdens and shorter life expectancies than other populations. Advance care planning (ACP)– is a process that involves having conversations between patients, family members, and clinicians about one’s goals or wishes for end-of-life care, and then documenting decisions in an advance directive. When introduced early in illness trajectories, ACP reduces the likelihood of poor end-of-life care for patients and improves long-term psychological outcomes for decision-makers. Previous research has found that NA tribal members are both interested and willing to discuss ACP but that there are substantial gaps in opportunities for NAs to engage in ACP. The long-term goal of this research is to explore how to increase ACP engagement for Native communities, specifically the Washoe Tribe. The Hello game is an evidence-based ACP conversation tool that involves groups of players responding to open-ended questions related to their goals, values, and beliefs about end-of-life issues and then discussing responses with one another. Hello may be particularly well suited for NA groups because it has a natural inclination toward storytelling and group connection, which are highly valued in most NA tribes. The objective of this R34 planning grant is to continue our partnership with the Washoe Indian Tribe to explore how Hello could be adapted for the Washoe tribe and to prepare for a cluster randomized trial assessing its impact on tribal ACP behaviors. We will pursue two specific aims. First, we will expand our partnership with the Washoe tribe to further explore the needs, motivations, and challenges related to ACP and end-of-life decision-making for tribal members and explore how findings converge or diverge from other populations and across Washoe reservations (Aim 1). To do so, we will conduct talking circles with tribal members from each of the 4 Washoe reservations (n=48) to explore beliefs about and motivations for ACP, if and how storytelling plays a role in ACP and define meaningful and appropriate ACP outcomes. Then we will adapt the game based on those findings and test the adapted game for use by the Washoe tribe and test procedures for measuring impact of the game on ACP engagement (Aim 2). To do so, we will enroll n=60 participants who will play the adapted Hello game. Outcomes (ACP engagement and AD completion) will be collected 3 months later. The impact of the future R01 trial will be to improve Washoe population and community health by providing opportunity for appropriate ACP interventions to increase the likelihood that Washoe tribe members engage in ACP and complete advance directives, thereby furthering their self-determination for future healthcare in a way that is consistent with their goals, values, and beliefs.

NIH Research Projects · FY 2025 · 2025-09

PROJECT SUMMARY The human gut is colonized by trillions of microbial symbionts that defend against pathogenic invasion, regulate host immunity, and convert nutrients into host-absorbable metabolites. Gut microbes have evolved adaptations to conserve energy during colonization and survive in this highly competitive ecological niche. For example, members of the Bacteroidetes family employ pyrophosphate, a byproduct of DNA, protein, and glycogen synthesis, to drive central metabolic reactions and conserve nucleotide triphosphate (NTP) pools. Adaptations such as these contribute to the prevalence of Bacteroidetes, constituting up to half of all bacteria in the human intestine. Our lab has extensively studied a conserved Bacteroides transcription factor, called Cur, that encodes products necessary for colonization and regulating T-cell populations in the intestine. For example, the cur- dependent gene, fusA2, is a unique translation elongation factor that facilitates GTP-independent protein synthesis, a process that conserves NTPs and is necessary for intestinal fitness. Furthermore, Cur is directly responsible for the transcription of BT4295, an outer membrane protein that induces T-cell differentiation. We have previously demonstrated that the abundant dietary sugars, glucose and fructose, dominantly inhibit Cur activity. I have recently established that these simple sugars inhibit Cur via hierarchically governed ATP- and pyrophosphate (PPi)-dependent fructose bisphosphate (FBP) biosynthetic pathways. Remarkably, the canonical ATP-dependent glycolytic pathway is dispensable for in vitro growth and only necessary to control Cur during in vivo colonization because PPi-dependent enzymes are primarily responsible for the glycolytic load. These findings demonstrate that the role of ATP-dependent FBP synthesis is to regulate Cur during intestinal colonization, rather than producing energy equivalents via glycolysis; however, the mechanism by which FBP governs Cur activity has not been established. Other members of the Bacteroides family require FBP to synthesize intracellular glycogen, a process that is necessary for (i) the utilization of cur-dependent, but not - independent, sugars, (ii) Cur activation during carbon limitation, and (iii) fitness in a murine intestine. Collectively, the preliminary findings suggest that FBP and glycogen biosynthetic pathways form a cyclical regulatory pathway that controls Cur based on nutrient availability in the intestine. Therefore, I hypothesize that FBP governs Cur activity by regulating glycogen metabolism in response to intestinal nutrient availability. In Aim 1.1, I will investigate the role of FBP in promoting glycogenesis in Bt using an FBP-conjugated affinity resin coupled with enzymatic assays. In Aim 1.2, I will identify glycogenic genes that govern Cur activity during nutrient limitation by engineering Bt mutants and measuring effects on cur- dependent genes. In Aim 2, I will elucidate the signal that is produced by glycogen metabolism during nutrient limitation using a recombinant, affinity-tagged Cur protein to capture endogenous metabolites.

NIH Research Projects · FY 2025 · 2025-09

Rh Immunoglobulin (RhIg) is a human blood product with finite supply. There is currently a shortage in the United States, and international shortages are common. There is proven benefit for giving RhIg at delivery and in the 3rd trimester. However, there is mounting evidence from population studies and indirect clinical research showing that there is limited benefit to giving RhIg for bleeding in pregnancy at <12 weeks gestation. Professional medical societies are divided in their clinical guidance. The World Health Organization (WHO), Society of Family Planning (SFP), and American College of Obstetricians and Gynecologists (ACOG), among others, do not recommend giving RhIg at <12 weeks gestation. The Society for Maternal Fetal Medicine in the United States still recommends RhIg at all gestational ages, and some international recommendations fall in between. Many organizations allow for shared decision-making with patients outside of routine recommendations; however, to date we do not have published data on patient preferences about RhIg. There is not currently a unified standard of care and patients are caught in the middle. The long-term goal of this research is to identify the earliest gestational age at which RhIg administration is necessary and redistribute this finite human blood product for evidence-based indications. The specific objectives of this proposal are to directly measure the rate of sensitization in pregnant patients with bleeding at <12 weeks gestation and ascertain patient risk tolerance pertaining to RhIg. The central hypothesis is that <1.5% of patients will become sensitized following bleeding at <12 weeks gestation. The rationale for the proposed research is that directly measuring sensitization will align professional medical organization recommendations, conserve this human blood product for evidence-based indications, and potentially save the U.S. healthcare system $313 million annually. This study will fill that gap from two perspectives: direct scientific evidence determining the RhD-sensitization rate after bleeding in RhD-negative patients foregoing RhIg, and patient perspectives on risk using discrete choice experiments. The proposed work is innovative because it has the power to shift the paradigm for RhD status determination and RhIg administration in early pregnancy and inform alignment of professional medical organization recommendations around evidence-based, patient-informed care. At the completion of this project, results from Aim 1 will inform the science and recommendations for clinical care, and Aim 2 will provide the patient perspective to allocate this finite resource where it is most valued, and support evidence-based, high-value healthcare.

NIH Research Projects · FY 2025 · 2025-09

Abstract Co-transcriptional and post-transcriptional mechanisms play central roles in regulating gene expression. Understanding how these mechanisms control gene expression and, thus, cellular homeostasis is essential for the development of novel therapeutic approaches. Splicing is a co-transcriptional process during which introns are removed from pre-mRNAs and the remaining exons are connected. Connecting the exons in different combinations is called alternative splicing (AS), a process that generates diversified mature mRNAs from the same gene. AS plays crucial roles in regulating gene expression, and mis-splicing is implicated in different diseases. Thus, AS is a tightly regulated process. In spite of its well-established roles, AS is understudied in the context of fracture healing. Proteoglycan 4 (PRG4) is an extracellular matrix protein found throughout the animal kingdom and is best known for its lubricant effects in articular cartilage. PRG4 is highly expressed in the synovial fluid and possesses chondroprotective effects; therefore, exogenous expression of recombinant PRG4 in the articular cartilage halts the progression of osteoarthritis. PRG4 is also expressed in organs other than articular joints, including the liver, heart, and bone. However, the biological functions of PRG4 in these tissues are not well defined. Importantly, the expression pattern and biological functions of PRG4 during fracture healing have never been characterized. Our preliminary data indicate high expression of Prg4 in the callus periosteal stem cells (PSC) during the inflammatory phase of fracture healing. Interestingly, Prg4 is predominantly expressed in callus PSC as a splice variant that lacks 3 coding exons and has bever been reported in any musculoskeletal tissue. This splice variant is conserved in human cells. TGFB1 significantly induces Prg4 expression and reprograms Prg4 splicing, which makes Prg4 expression and splicing pattern in the callus PSC distinct from those in the intact- bone PSC. Inhibiting the expression of Prg4 in the callus results in reduced abundance of PSC, defective soft- callus formation, and reduced callus mineralization and bone formation. Thus, we hypothesize that Prg4 undergoes a unique splicing pattern in the callus that is mediated, at least in part, by TGFB1, resulting in a splice variant that plays critical autocrine and paracrine regulatory roles and impacts different healing phases. In Aim 1, we will assess the roles of the Prg4 splice variant in different healing phases and in maintaining the homeostasis of different cell types in the callus. In Aim 2, we will study the autocrine effects of PRG4 and how it regulates the homeostasis and differentiation of PSC. In Aim 3, we will identify the molecular pathways that regulate Prg4 expression and splicing, define the unique roles of different splice variants of Prg4 in regulating PSC and human BMSC homeostasis, and determine the receptors via which Prg4 signals. Completion of our studies will bridge several knowledge gaps and identify novel roles of PRG4 in bone repair.

NIH Research Projects · FY 2025 · 2025-09

ABSTRACT A complete understanding of the underlying mechanisms of pain chronification – how temporary acute pain becomes a permanent problem – remains elusive. Pain chronification mechanisms have been explored in the peripheral nervous system and the spinal cord, but the supraspinal mechanisms of chronification are understudied. fMRI is a powerful tool that can detect subtle changes in brain function, including changes in network-level connectivity while at cognitive rest. The Default Mode Network (DMN) is a network that subserves internally directed cognition, deactivating in response to externally directed attentional needs. The DMN has repeatedly been found to have abnormal within-network connectivity in patients with chronic pain. Interestingly, increased intra-DMN connectivity is associated with pain rumination, a psychological symptom of chronic pain similar to the rumination characteristic of Major Depressive Disorder (MDD), a common comorbidity of chronic pain. Abnormal DMN connectivity has been found in patients with MDD, and in people at high risk of developing MDD, suggesting that abnormalities in this network’s connectivity may precede psychological dysfunction. From this, we believe that abnormal DMN connectivity may also precede chronic pain, beginning before acute pain chronifies. We hypothesize that the change in DMN connectivity may be a supraspinal mechanism of pain chronification. This proposal aims to characterize DMN connectivity in a rat model of peripheral nerve injury, examining the rats longitudinally as neuropathic pain progresses. This proposal extends ongoing clinical work seeking connectivity biomarkers predictive of pain chronification in acute musculoskeletal trauma. Additionally, this proposal will explore a potential mechanism of connectivity change: localized neuroinflammation. Multiple brain regions become inflamed after peripheral neuropathic injury, including the prefrontal cortex, hippocampus, and brainstem. It is, therefore, likely that other nodes of the DMN may also experience localized inflammation. This proposal will characterize cytokine and chemokine expression in multiple DMN nodes after peripheral nerve injury to examine the natural inflammatory processes that may occur. Additionally, this proposal will test if microglial silencing in the DMN using site-specific minocycline administration can reverse changes in DMN connectivity and both evoked and spontaneous pain behaviors. Collectively, these results will provide foundational data on the significance of inflammatory processes in the DMN, and of intra-DMN connectivity more broadly, to the propagation of pain after peripheral nerve injury, justifying future longitudinal clinical studies and providing new targets for the prevention of pain chronification.

NIH Research Projects · FY 2025 · 2025-09

PROJECT SUMMARY Pediatric ventricular assist devices (VADs) are urgently needed to support children with heart failure awaiting transplant, especially given the scarcity of donor hearts and the complications associated with congenital heart disease. Currently, no VADs are approved for long-term use in the U.S. for children weighing approximately 10–35 kg. The immediate goal of this research is to test and refine a small and durable centrifugal blood pump (named PSU Child VAD) that we recently developed for use in children approximately 10-35 kg (BSA 0.5-1.2 m2, 1-11 years of age, and mean cardiac output of 1.5-3.5 LPM) with the weight variation of ~±1kg for 1 year old and ~±10kg for 11 year old based on growth charts developed by the Centers for Disease Control and Prevention (CDC). The device will be equipped with the optional near-physiologic pulsatility. A chronic in-vivo study was conducted on a lamb for 26 days elective, demonstrating promising biocompatibility with no evidence of end-organ failure. The goal will be achieved by three complementary, but independent aims; Aim 1) to test the prototype (Rev 0.0) PSU Child VAD through a series of 30-day in-vivo studies to validate the design and determine if the system meets the design requirements. We hypothesize that the in-vivo studies with PSU Child VAD will result in hemo-/biocompatible outcomes in terms of minimal blood trauma and no end- organ failure; Aim 2) to refine the design of PSU Child VAD (Rev 1.0, 2.0) based on the outcomes from in- silico, in-vitro, and in-vivo studies by following the FDA Design Controls approach. We hypothesize that the FDA Design Control Approach-based design iteration will result in superior hydraulic efficiency and hemo- /biocompatibility. This design is expected to minimize the occurrence of thrombosis, von Willebrand factor degradation, and hemolysis while maximizing hydraulic efficiency.; Aim 3) to develop a controller capable of providing synchronous co-pulsation to provide physiologic pulse pressures. The rationale in Aim 3 is that continuous flow blood pumps operating at a fixed speed cause static, non-physiologic pressure waveforms, which is known to cause physiologic dysfunction, such as gastrointestinal bleeding, reduced baroreflex response, and destruction of von Willebrand factor (vWF). We hypothesize that the controller will be capable of modulating the pump speed to provide physiologic arterial pulse pressure, thus balancing the physiologic levels of vWF. The proposed work is innovative because it is specifically designed to provide long-term (bridge-to-transplantation, BTT) cardiac support that fits the complex anatomy of children while also accommodating their somatic growth. This is significant because it can lead to hospital discharge and avoid the need for multiple surgeries. The long-term goal of this research is to develop a fully implantable system with the ultimate aim of enhancing the survival and quality of life for children in BTT. If successful, the device will directly benefit children awaiting donor hearts by significantly enhancing both their chances of survival and overall quality of life.