University Of Washington

NIH Research Projects · FY 2026 · 2026-05

ABSTRACT In this project, we aim to unravel the structural basis of a novel parasteric mechanism of inhibition of bacterial adhesion. This mechanism was discovered against the main adhesin of uropathogenic E. coli—the mannose- specific fimbrial lectin FimH—which is a critical urovirulence factor and a major vaccine target. FimH is an allosteric protein that exists in two conformations: a low-affinity “inactive” state and a high-affinity “active” state. We found that these alternative conformations of FimH are recognized by different monoclonal antibodies, which have distinct inhibitory effects on the adhesin’s ability to bind mannose receptors. Cryo-EM structures of these antibodies in complex with FimH have been recently resolved, and this information will be utilized to characterize the ability of certain antibodies and de novo-designed miniproteins to mediate parasteric inhibition. A unique hallmark of this type of inhibitor is its ability to both block and reverse bacterial adhesion and biofilm formation. We will further define the structural details of the interactions between FimH and parasteric inhibitors and optimize these inhibitors before testing their efficacy in protecting against UTIs using a mouse model of passive intra-peritoneal immunization. Completion of these aims will facilitate the development of conceptually novel therapeutics against uropathogenic E. coli and other human pathogens.

NIH Research Projects · FY 2026 · 2026-05

Chronic rhinosinusitis (CRS) is a persistent inflammatory disease affecting 1 in 8 adults in the US. CRS profoundly affects health-related quality-of-life and is commonly treated with endoscopic sinus surgery (ESS). ESS fails to induce durable symptom improvements in 25% of CRS patients and subsequent revision ESS is needed in 15-46% of cases due to persistent or recurrent symptoms after incomplete surgical dissection. Revision ESS has significantly lower success rates than primary ESS and independently predicts poorer clinical outcomes. Complete surgical dissection, ideally during the first ESS, is less costly and is most likely to improve symptoms. Therefore, tools that enable complete ESS are critical. Image-guided surgery (IGS) can facilitate surgical dissection in ESS by mapping the location of surgical instruments to preoperative computed tomography (CT) images. However, IGS systems have significant limitations: 1) high costs, driving lower IGS usage, especially in underserved groups; 2) loss of tracking accuracy during ESS; and 3) disparity between the static CT images and reality as ESS progresses. We aim to establish a computer vision-based navigation system that will: 1) greatly reduce the cost of surgical navigation by eliminating expensive IGS hardware, thereby democratizing the use of navigation; 2) achieve consistent submillimeter accuracy during ESS; and 3) enhance surgical completeness to drive better clinical outcomes in CRS patients. The objective of this proposal is to develop a low-cost vision-based navigation system that reflects dynamic changes in surgical anatomy on the CT, maps critical anatomy from the CT onto a 3D reconstruction of the surgical field, and continuously tracks surgical instruments that are in view, aggregating these data in real-time for visualization. The central hypothesis is that vision-based navigation will maintain accuracy during ESS and will display critical anatomic structures and up- to-date anatomic changes to the surgeon, yielding more precise and complete operations. The rationale is that vision-based navigation will significantly improve and democratize navigation facilitating superior clinical outcomes at a lower cost for a larger cross-section of the population. We will test the central hypothesis in 3 specific aims: 1) Optimize the accuracy of high-fidelity 3D reconstructions of the sinonasal cavity using custom Neural Radiance Field-based techniques during surgery; 2) Refine automated co-registration of the CT volumetric model and 3D surgical scene reconstruction to enable dynamic anatomic updates, anatomic landmark display, and continuous surgical instrument tracking; and 3) Optimize the clinical interface and speed of computer vision-based navigation to enhance surgical performance. We will apply innovative computer vision techniques that harness the expertise of our team of surgeons and engineers. This research is significant because vision- based navigation will reduce existing limitations of IGS in ESS and could optimize endoscopic surgery in other disciplines. The expected outcome of this work is the development of a novel surgical navigation platform to enable more complete, lower cost ESS driving superior clinical outcomes for a larger proportion of the population.

NIH Research Projects · FY 2026 · 2026-05

Project Summary/Abstract: Adolescent girls and young women (AGYW) in sub-Saharan Africa account for one in four new HIV infections globally. Antiretroviral (ARV) drugs can prevent and treat HIV, yet non-adherence among AGYW persists as a public health challenge due to biological, economic, and social barriers. High adherence measured via drug levels in biological specimens correlates with HIV treatment and prevention efficacy, and studies demonstrate that providing drug level feedback (DLF) paired with supportive counseling improves outcomes. Furthermore, AGYWs receiving oral or extended release ARVs (like monthly vaginal rings) desire regular real-time DLF, while their healthcare providers assert that DLF facilitates candid conversations about non-adherence. Additionally, DLF can assess the effectiveness of adherence-promoting interventions by providing an objective marker of drug exposure. Yet current DLF tests are slow, expensive, and centrally analyzed. To address the critical need for accessible and inexpensive HIV DLF for AGYW, we aim to develop rapid enzymatic assays to measure HIV drug levels in routine care settings like pharmacies or clinics. Our approach represents a paradigm shift in DLF because it measures ARVs based on their enzymatic activity, enabling rapid (<30 min) and inexpensive measurement. We will expand on prior work led by Dr. Olanrewaju (PI) which developed and validated the REverse transcriptase ACTivity (REACT) assay to measure tenofovir diphosphate (TFV-DP), a nucleotide reverse transcriptase inhibitor (NRTI) used in all approved oral PrEP regimens, and expanded REACT to detect the non-nucleoside reverse transcriptase inhibitors (NNRTIs). In this proposal, we will: (1) Calibrate REACT to operate at recently established TFV-DP thresholds that indicate oral PrEP efficacy among cisgender women. We will also optimize REACT in plasma to measure the NNRTIs doravirine (DOR), rilpivirine (RPV), and dapivirine (DPV) used in oral and long-acting HIV treatment and prevention regimens that are scaling up in high- burden settings. (2) Integrate the assay into the Harmony portable device (developed by Co-I Lutz) that can be deployed in routine care settings. We will freeze-dry reagents to eliminate the need for cold reagent storage, simplify assay setup, and enhance the platform’s usability. (3) Evaluate the sensitivity and specificity of REACT for DLF among AGYW using banked clinical samples. We will measure TFV-DP and FTC-TP in banked clinical samples collected from AGYW in a pharmacologic study led by Co-I Mugwanya (R01AI155086), DPV from banked samples collected in a PrEP delivery study among AGYW (R01HD108041) led by Co-I Pintye, and DOR and RPV from people living with HIV enrolled in the University of Washington Center for AIDS Research Enhanced Specimen Collection Service. Our multidisciplinary team at the University of Washington is uniquely qualified to complete this work given our expertise in enzymatic assays, point-of-care diagnostics, clinical validation, and implementation science.

NIH Research Projects · FY 2026 · 2026-05

More than half of people living with HIV (PWH) in the United States (US) are 50 years of age or older. Compared with those without HIV, older PWH have 2.3-fold increased risk of depression. The impact of unmitigated mental health symptoms and related conditions among this growing population is significant and includes social isolation, loss of independence, and poor engagement with healthcare, undermining progress towards ending the HIV epidemic. Due to a shortage behavioral health providers, there is growing interest in innovative interventions using community-based, peer-led approaches to improve access to effective mental health services. Behavioral activation is an evidence-based intervention that has shown promise for reducing depressive symptoms among older adults. Our team has developed a streamlined lay-delivered behavioral activation intervention called “Do More, Feel Better” (DMFB) that has been shown to decrease depressive symptoms among depressed (PHQ-9 ≥10) older adults obtaining services in community senior centers. Delivery of an adapted version of the DMFB intervention for older PWH with poor access to professional counseling could be relatively straightforward within the existing Ryan White HIV/AIDS program, supported by organizations that provide essential services such as non-medical case management to low-income PWH. Because the intervention is tailored to individual preferences and needs, it promises to be acceptable, especially after careful adaptation using input from community members and stakeholders. Our aims for the proposed work are therefore: (1) to understand the impact of mental health issues on HIV care, functioning, and quality of life and identify multi-level barriers and facilitators that could influence participation in and delivery of an adapted DMFB intervention; (2) to adapt and enhance the DMFB intervention for delivery by case management program staff or volunteers to older PWH, following the ADAPT-ITT model in collaboration with community partners; and (3) to determine the acceptability, feasibility, and appropriateness of the adapted DMFB intervention compared to clinician-delivered Behavioral Activation therapy over 3 months in a pilot randomized controlled trial. Results of this research will have high impact by adapting an effective lay-delivered behavioral activation intervention for older PWH that is low-cost, scalable, and easily tailored to individual preferences and needs. Our ongoing work on the DMFB intervention indicates that this lay-delivered intervention has great potential to produce concrete improvements in mental health and quality of life. Our multidisciplinary team has a strong record of research on HIV care, geriatric mental health, HIV and aging, behavioral health and implementation science, and the experience with mixed methods approaches, intervention adaptation, and clinical trials necessary to successfully carry out this work. Adaptation of the DMFB intervention has the potential to be acceptable, feasible, effective and scalable when delivered within case management organizations, improving the lives and HIV outcomes of older PWH.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY / ABSTRACT Despite availability of HIV pre-exposure prophylaxis (PrEP) for over a decade, many persons who could benefit from PrEP have not yet accessed PrEP services. Implementation of pharmacy-based PrEP is a promising strategy that presents opportunity to overcome barriers related to clinic distance and stigma and to increase PrEP access, uptake, and continuity of treatment among individuals who would benefit most. Despite the fact that team member and pharmacist Dr. Elyse Tung started the first pharmacy-based PrEP clinic nearly ten years ago, PrEP still is not widely available through pharmacies without a prescription from a doctor or other licensed clinician. As of 2024, not all states allow pharmacists to prescribe medications independently, and many insurance companies erect barriers to providing compensation to pharmacists for this role. Implementation science projects are needed to develop, refine, and evaluate the training and educational support required by pharmacists to expand their scope of practice. Health economics work is also needed to determine whether there are incremental financial benefits for pharmacies to provide injectable PrEP in addition to oral medications and to evaluate the cost-effectiveness of providing PrEP through telehealth. In response to RFA MH-25-185, we propose three specific aims. Aim 1 will build on a current supplement through the Ending the HIV Epidemic (EHE) initiative that is funding a pilot project to evaluate an online virtual community of practice (VCoP) for pharmacists and pharmacy staff to increase their knowledge, capabilities, and comfort in prescribing PrEP. Aims 2 and 3 will conduct financial analyses to provide information for new pharmacy implementation and use time and motion data to compare the costs and benefits of providing injectable PrEP versus oral PrEP and in-pharmacy visits versus telePrEP. This project addresses the Prevent pillar of the EHE plan with a secondary impact on the Diagnose pillar. This project also addresses the NIH HIV/AIDS Research Priorities (NOT-OD-20-018) to reduce HIV incidence by testing new prevention strategies and training the workforce. It is in synergy with the local EHE plan, the Washington State Department of Health, and the National HIV/AIDS Strategy. The national strategy specifically calls out to leverage pharmacists’ knowledge and accessibility in nearly every urban and rural community as part of a comprehensive HIV prevention and care strategy. Ultimately our goal is to provide more PrEP options and motivate pharmacists and pharmacy owners to expand access points for PrEP care in locations and to populations disproportionately impacted by HIV infection in order to end the HIV epidemic.

NIH Research Projects · FY 2026 · 2026-05

Project Summary The goal of the proposed work is to develop ultrahigh multiplexing (>1000 plex) fluorescent probes and methods for using them in high-resolution spatial transcriptomics of both thin (~5-10 m) and thick (> ~200 m) tissue samples in a single round of staining and fluorescence imaging. Spatial transcriptomics allows cell phenotyping in the context of tissue structure, and has become essential in biomedical research. However, current spatial transcriptomic technologies rely on either time-consuming cyclic imaging approaches (multiple rounds of staining, imaging, and de-staining) or complex, expensive, and lower- resolution sequencing approaches, and there is no commercial technology for spatial transcriptomics in thick tissue samples. A new technology is needed to streamline spatial transcriptomics for both thick and thin tissue samples for high volume clinical and research use. To address this need, we propose to create a set of over 1000 spectrally barcoded fluorescent probes, and to develop methods for using these barcodes as spatial transcriptomics probes in both thin and thick tissue samples. To create a set of 1024 probes for diverse spatial transcriptomics applications, we will conjugate the spectral barcode fluorescent probes with DNA oligonucleotide (oligo) barcodes that will allow labeling of any mRNA target via an intermediary target- and barcode-specific oligo adapter. We will design, synthesize, and characterize a set of 1024 spectrally and DNA barcoded probes that can be used in single molecule fluorescence in situ hybridization (smFISH) to image any set of up to 1024 target RNAs, and will make this probe set available to the research community for use in spatial transcriptomics applications. We will develop these ultrahigh multiplexing fluorescent probes and methods for using them in spatial transcriptomics of thin and thick tissue samples by (1) synthesizing and characterize a set of 1024 unconjugated spectral barcodes; (2) demonstrating 128-plex single-round mRNA imaging in thin (~5-10 m) tissues; and (3) demonstrating 128-plex mRNA FISH in thick (> ~200 m) tissues. To ground our technology development with an impactful use case, Aims 2 and 3 will apply the probes to constructing a spatial cell atlas of the glomerulus in adult and aged mouse kidney tissues, which will complement our ongoing glomerulus atlas effort based on protein and carbohydrate imaging. 128-plex RNA imaging of thin tissue sections in a single round of staining and imaging would be a breakthrough technology (1-2 orders of magnitude high multiplexing than current single-round imaging methods), and ultrahigh multiplex RNA imaging is currently not possible in thick tissues; future work will increase the level of multiplexing.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY/ABSTRACT The goal of this project is to develop tools to determine the mechanisms by which single amino acid variants affect myosin structure and function at multiple scales. Major challenges have been that: 1) a limited number of human β-myosin structures; 2) the computational expense (CPU time) to simulate the dynamics of such a large protein, and 3) difficulty in obtaining tissue from patients with disease causing variants. To overcome these challenges, we developed new structure-based, dynamics models of the chemo-mechanical cycle of β-myosin. These models are generated from new human crystal and cryo-EM structures, augmented by known structures available from bovine muscle. Our Molecular and Brownian Dynamics models contain F-actin structure to study how its interactions with β-myosin affects signaling between the nucleotide binding pocket, the actin-myosin interface, converter domain and other regions of myosin. These simulations are augmented by our novel inter- protein pathway analysis based on graph theory. We will use stochastic-kinetic models of sarcomeres to simulate contraction and relaxation with variable amounts of myosin variants. We will use gene edited human inducible pluripotent stem cells (hiPSCs) to validate our results. Our culture conditions result in myofibrils expressing predominantly β-myosin and demonstrate kinetics of adult myofibrils. We will purify myosin from these hiPSC- CMs for biochemical kinetic measures of the chemo-mechanical cycle. Each of these mechanical states results from structural changes in myosin and its association with actin. Additional studies will be performed at the level of myofibrils to study how mutations affect contractile function. We will also use single molecule, super-resolution to study high resolution structural changes in thick filaments from hiPSC-CMs, and Molecular Dynamics models of the Interacting Heads Motif structure of myosin on the thick filament backbone. This platform will be used to predict the effect of a selected group of variants of uncertain significance (VUSs).

NIH Research Projects · FY 2026 · 2026-05

Predictions of drug disposition and toxicity from preclinical data, estimation of risk of drug-drug interactions and simulation of drug exposures in humans are essential for safe and effective drug development and clinical pharmacology. Despite decades of research, significant gaps still remain in translating preclinical findings to clinical drug development and practice. As a result, about 90% of drug candidates that enter Phase I clinical trials fail during development. In addition, uncertainty regarding the disposition characteristics of approved drugs often remains after drug approval leading to post marketing studies and label revisions. This wastes resources, leads to unnecessary risk to patients and limits access to life saving medications for specific patient populations. My laboratory works to bridge the knowledge gaps in translational science via mechanistic in vitro studies, mass spectrometry based proteomics experiments and state-of-the art in silico modeling. We develop novel proteomics methods to understand formation of drug adducts by small molecule drugs, evaluate how drug-protein and protein-protein interactions within a cell alter drug distribution and the activity of drug metabolizing enzymes, and assess how genetic variability and individual biology such as sex, disease and age alter drug exposures in tissues and in blood. Central questions of my research program include: What mechanisms cause significant under and overpredictions of drug exposures and drug-drug interactions in humans? Which individual factors define interindividual variability in drug-protein adduct formation making certain individuals highly susceptible? What mechanisms lead to changes in drug clearance in specific populations and between individuals? Answering these questions will advance developing individualized therapy and enable connecting observable patient specific factors with decisions of drug dosage adjustments. Our long term goal is to improve the preclinical, translational and computational methodologies used to predict and evaluate drug disposition and adverse drug reactions. Our current studies are focused on 1) development of innovative proteomic methods for discovery, characterization and quantification of protein adducts in simple and complex biological matrices; 2) evaluation of the role of fatty acid binding proteins in modulating tissue drug distribution and drug clearance and 3) developing novel physiologically based pharmacokinetic models to predict drug disposition in specific populations including vulnerable patients. Our studies advance innovative areas such as how intracellular binding proteins influence drug efficacy, and provide unprecedented insight into mechanisms of enzyme inactivation and quantitative relationships between adduct formation and metabolic activity in the liver. Our research will also provide open and accessible cutting-edge tools for high-dimensional proteomics data and novel PBPK models for prediction of drug disposition in specific patient populations. Our work promises to decrease failure rate during drug development and lead to expanded access to approved medications in specific patient groups through improved quantitative systems biology approaches.

NIH Research Projects · FY 2026 · 2026-05

Abstract Currently, over 11% of the US population (nearly 40 million people) are affected by type 1 or type 2 diabetes (T1D or T2D), with T2D representing >90% of diabetes cases. In addition, 97.6 million youth and adults have pre-diabetes and are therefore at high risk of developing T2D and associated vascular complications. Alarmingly, T2D is rapidly increasing in youth, with incidence projected by some models to rise by 700% between 2017 and 2060. Youth-onset T2D is characterized by more severe insulin resistance than adult-onset T2D, and a substantial incidence of arterial stiffening—an early marker of atherosclerotic cardiovascular disease (CVD). Since both T1D and T2D markedly increase the risk of CVD, and because CVD events occur at younger ages in people with diabetes, it is critical to understand how diabetes increases CVD risk and how CVD can be prevented. Preventive strategies likely need to start early in youth. Although LDL-cholesterol lowering for CVD risk reduction is recommended for children >10 years of age as in adults with high CVD risk, a substantial residual CVD risk remains. This residual CVD risk in individuals with diabetes is linked to abnormal metabolism of triglyceride-rich lipoproteins (TRLs). Size-distributions and concentrations of TRL particle subpopulations and their partly-lipolyzed remnant lipoprotein particles (RLPs) are governed in part by apolipoprotein C3 (APOC3) and may predict CVD risk in adults and youth with diabetes. We hypothesize that increased hepatic APOC3 production resulting from adipose tissue insulin resistance in both T2D and T1D causes accumulation of a mid-sized atherogenic TRL particle subpopulation. These particles promote CVD by increasing vascular inflammation, with changes occurring early in youth at risk for CVD. This research program will ask three overarching questions to address this hypothesis: i) Does increased plasma APOC3 associate with accumulation of a mid-sized TRL particle population and worsened trajectories of insulin resistance and arterial stiffness in youth with T1D or T2D?; ii) How do TRL/RLP subpopulations differ structurally and functionally?; and iii) Does dysfunction in the hepatic sortilin 1-APOB100 secretion pathway explain the increased APOC3 secretion and atherosclerosis in diabetes? By combining longitudinal and mechanistic studies in youth with diabetes with investigation of mouse models of diabetes-accelerated atherosclerosis and cell systems, we believe we are in an excellent position to fill an important and clinically significant gap in our understanding of how diabetes promotes CVD risk and to identify new treatment and prevention strategies.

NSF Awards · FY 2026 · 2026-05

Simulating physical systems, like how fluids flow or solids deform, is the backbone computational science and engineering. But in order to simulate how a physical system evolves, we have to first describe its shape. This is the problem of mesh generation: How does one take a geometric model of an engine, a lake, a building and decompose it into a mesh of triangles or tetrahedra? Programs for mesh generation are difficult to develop. They require precise and non-standard arithmetic to avoid catastrophic errors, and they rely on some of the most complicated data structures in Computer Science. As a result, most programs for mesh generation are so difficult to change that they are now outdated relative to the capabilities of modern hardware. In this project, the investigators are developing meshing algorithms alongside machine-checked proofs of their correctness. The project’s novelties are to develop proven correct meshing algorithms for the first time, and more generally to develop reusable methodologies for creating geometric software alongside its proof of correctness. In particular, the investigators will re-implement the award winning “Triangle” library for Delaunay triangulation in the language Rocq, develop new, re-usable arithmetic predicates and new relational data structure methodologies for use in this and other correct-by-construction software projects. Quite often, meshing dominates the cost and is the principal constraint on numerical accuracy of a simulation. The project’s impacts are to speed up simulations and improve their accuracy. The migration of key geometric libraries and subroutines to a correct-by-construction methodology also helps with long-term maintenance of such critical software infrastructure. The project work is organized in four interrelated tasks. The first subsystem concerns the development of Rocq-verified, staged floating-point predicates in the style of Priest’s big-float arithmetic, following Jonathan Shewchuk’s original work. In particular, the investigators will exploit SIMD vector hardware available on all commodity CPUs to realize speedups. The second subsystem concerns the development of a Rocq-embedded relational data structure synthesis DSL, with application to mesh data structures embedded in Rocq. The investigators anticipate that this component will be more broadly useful to the community of Rocq programmers. The third task is to reimplement basic forms of Delaunay triangulation in a manner such that they can be swapped out for Triangle seamlessly. The fourth task is to reimplement basic forms of Delaunay tetrahedralization in 3d. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY / ABSTRACT Modeling and simulation are essential to modern cell biology research, but modeling tools have not kept pace with experimental work. In particular, many of the subcellular structures that are routinely investigated by modern microscopy methods can only be modeled at present with custom software. This is because no general-purpose simulators can simultaneously represent proteins, filaments (e.g. DNA and actin), and membrane dynamics. Such capability is essential for investigating fundamental cellular processes such as transcription, cell division, endocytosis, and cell motility. We will develop the necessary algorithms and implement them in our existing Smoldyn software, a widely used tool that is a leader in the spatial modeling field. One of our algorithm sets will focus on filament dynamics. It will accurately capture bending, twisting, branching, and excluded volume effects for filaments, along with interactions between filaments and both molecules and surfaces. These interactions will support simulation of molecular motors, DNA transcription, and feedback from filament- bound proteins to the filament conformations. Our algorithms will represent filaments at a high level of detail and will simulate efficiently through the use of multiple solvers that are optimized for different parameter options. Another algorithm set will focus on membrane dynamics, such as deformation, endocytosis, and cell division, along with the intracellular interactions that arise in those processes. The resulting simulator will be able to model a wide range of elementary cell biology processes and, by extension, most of the complexity of real cells. Our research team includes members from a lab that combines experimental and theoretical work. They will use our software, as it is developed, to model actin assembly against load from membrane elasticity and actin-driven endocytosis. This portion of the work will help motivate and direct the methods development work because it will use a wide range of our new software features. It will also be important in its own right because it will address open questions about the reciprocal relationships between actin- driven forces, actin architecture, and membrane shape in endocytosis. We will continue to work closely with the broader biochemical modeling community through software support and help with integrating our software into other tools as a back-end physics engine. We will also work with the community in the ongoing development of a standardized language for describing spatial cell biological models. We anticipate that our work will have a high impact in cell biology research because it will enable realistic spatial modeling for systems that cannot be modeled at present with existing tools. Many researchers have directly requested these software features, in person and in letters of support.

NIH Research Projects · FY 2026 · 2026-05

Project Summary/Abstract The cerebellum is essential for ensuring precise and coordinated movements. Central to this function is the cerebellar cortex, which integrates sensory and motor signals carried by mossy fiber projections. These signals are transformed by Purkinje cells (P-cells), the sole output neurons of the cortical circuit, into simple spike activity that fine-tunes motor commands in real time. Despite extensive knowledge of the relevant anatomy, we still do not know how mossy fiber inputs are dynamically transformed within the cortical circuit to generate P-cell simple spikes. This gap persists largely due to the challenges of recording and manipulating the activity of targeted cell types and pathways within the cerebellum of awake, behaving animals. The oculomotor system offers a unique model to address this problem. The brainstem premotor neurons driving saccades are well characterized, as are their mossy fiber projections to the oculomotor vermis (OMV, lobules VIc and VII). Mossy fibers from both the nucleus reticularis tegmenti pontis (NRTP) and the paramedian pontine reticular formation (PPRF) project bilaterally, with the NRTP relaying desired saccade amplitude from the superior colliculus and the PPRF providing corollary discharges of motor commands to motoneurons. However, how the OMV processes these signals to regulate saccades remains unknown. Our recent experiments revealed that P-cell-specific optogenetic stimulation affects saccades in direction-dependent ways. Stimulation during contraversive saccades reduces velocity at short latency. In contrast, stimulation during ipsiversive saccades produces a delayed effect, manifesting as prolonged deceleration. These latency differences cannot be explained by interactions with mossy fiber saccadic burst signals, which are time-locked to saccade onset. Instead, our findings suggest that the OMV cortical circuit processes mossy fiber inputs differently for each direction, leading to differences in how and when P-cell simple spike activity influences saccade dynamics. Specifically, we hypothesize that the OMV functions as a feedforward controller for contraversive saccades and as a temporal integrator within a negative feedback loop that governs the termination of ipsiversive saccades. The implementation of these direction-dependent mechanisms is unclear. P-cells project to the deep cerebellar nuclei and back to the cortical circuit via axon collaterals, suggesting two possibilities: delays may arise from downstream brainstem circuits or an internal switching mechanism within the OMV that modulates mossy fiber processing. To resolve this issue, we will use optogenetics to perturb PPRF mossy fiber inputs to the OMV while simultaneously recording P-cell activity. While this approach is well-established in rodent models, it has not yet been applied in non-human primates, providing a novel opportunity to determine how the OMV processes saccade-related signals and resolves direction-specific differences.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY/ABSTRACT Cell death plays a central role in the pathogenesis and exacerbations of systemic lupus erythematosus (SLE). Many of the best recognized autoantigens in SLE are intracellular nucleic acid-binding proteins, some of them located in the cell nucleus. While early work focused on apoptosis, the first known form of programmed cell death, attention has shifted in recent year to several more inflammatory types of programmed cell death resulting in exposure of cellular contents together with alarmins, danger signals, and damage-associated molecular patterns (DAMPs), which stimulate antigen-presenting cells to provoke a much stronger immune response. Inflammatory modes of cell death include NETosis, pyroptosis, ferroptosis, and necroptosis. These newer inflammatory pathways of cell death have been proposed to be important in SLE, but it is not known if they even occur in patients. Progress is hampered by a lack of established assays for measuring their occurrence in vivo in patients. We will use targeted, as well as unbiased, approaches to establish assays (biomarkers) that can selectively measure the presence of pyroptosis, necroptosis, and ferroptosis in patient blood samples (compared to NETosis). In brief, neutrophils and monocytes will be induced to undergo programmed inflammatory cell death and cellular and soluble constituents analyzed by microscopy, ELISA, and mass spectrometry. Our preliminary data suggest that ferroptosis is much increased in neutrophils from SLE patients. Ferroptosis will be assessed using fluorescent markers of lipid peroxides and iron accumulation and the degree of ferroptosis will be related to demographics, sex, and clinical phenotype, including disease activity. Levels of soluble ferroptosis biomarkers will be assessed by ELISA and associated with neutrophil ferroptosis as well as with clinical markers of disease activity. This is a high-risk, but high-reward proposal: a reliable quantification of the inflammatory programmed cell death pathways pyroptosis, ferroptosis, and necroptosis would have significant utility as biomarkers for patient stratification and to fill gaps in our understanding of the molecular pathology of SLE. These biomarkers would have similar utility in many additional autoimmune and autoinflammatory conditions. At present, these cell death pathways are well defined in vitro, but their presence in vivo remains a black box.

NIH Research Projects · FY 2026 · 2026-05

Abstract Currently, there are no effective therapies to replace degenerated neurons in patients with retina neuron loss from degenerative diseases, such as occurs in patients with glaucoma and macular degeneration. By contrast, retinas of non-mammalian vertebrates, such as fish and amphibians, show a robust regenerative response following retinal damage. Upon injury to the retina, fish Muller Glia generate all different types of retinal neurons to replace those that were lost. There has been considerable progress in understanding the molecular mechanisms of regeneration in non-mammalian vertebrates, and if this knowledge could be applied to humans, it might lead to the development of new types of regenerative therapies for patients with impaired vision. Over ten years ago, we discovered that by expressing a key proneural regulatory gene, called Ascl1, in the Muller glia of mice, we can induce them to regenerate new neurons in vitro (2013) and in vivo (2017). The new regenerated neurons in the mouse retinas wired up with the existing, undamaged neurons and became functional. These results showed for the first time that functional neuron regeneration is possible in mammals, like ourselves; however, we have found that additional factors are likely required to guide the regeneration to the proper types and numbers of neurons needed to address specific diseases. In this proposal, our Aims are (1) to test whether this approach can work in human Muller glia and adult non-human primate; (2) to better define the specific transcription factor combinations that best regenerate cone photoreceptors from Muller glia; and (3) to determine whether epigenetic repressive chromatin restricts the potential of Muller glia to more efficiently regenerate all retina neuron types. At the end of five years, we expect to have further refined the potential for regeneration in the treatment of retinal disease and trauma in humans and developed a strategy to realize the clinical potential of this approach.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY / ABSTRACT Schistosomiasis affects over 200 million people worldwide and is driven by granulomatous inflammation and fibrotic remodeling in response to schistosome eggs trapped in host tissues. While macrophages are key contributors to this pathology, the role of vascular endothelial cells (VECs)-the first host cells to encounter deposited eggs-remains understudied due to limitations in current models. To address this, we propose a 3D Schistosomal vessel-on-a-chip (Schisto- VoC) platform that mimics key features of the human vascular microenvironment, including physiologic flow, endothelial-macrophage co-culture, and controlled delivery of egg-secreted products (ESP). Preliminary data indicate that VECs respond to eggs and ESP with inflammatory activation and partial endothelial-to-mesenchymal transition (EndMT), suggesting a role in guiding macrophage polarization. In Aim 1, we will engineer a perfusable microvascular network and integrate tunable hydrogel microspheres and live eggs to dissect biomechanical and biochemical cues that drive VEC remodeling. In Aim 2, we will assess how ESP-activated VECs influence macrophage polarization by evaluating M2 polarization markers, cytokine secretion, and 3D migration phenotypes. Pharmacologic inhibition of key pathways: NF-κB, Notch4-DLL, and TGF- β will clarify their contributions to EndMT and immune crosstalk. This work will uncover novel immune-endothelial mechanisms in granuloma formation and fibrosis and establish a standardized platform for antifibrotic drug discovery.

NIH Research Projects · FY 2026 · 2026-05

ABSTRACT Technologies that combine the microscale manipulation of tissues and fluids offer the exciting possibility of miniaturizing disease models and drug testing workflows. Such technologies enable inexpensive, more efficient tests of high clinical biomimicry, maximizing the use of scarce human biopsies while minimizing animal testing. Notable examples are patient-derived organoids (PDOs) and organs-on-chips (OOCs). Traditional approaches using tissue culture and animal models offer a nearly-infinite supply of tumor tissue, but, unfortunately, they are extremely poor predictors of disease outcomes and lack key anatomical and pathophysiological features of the real patient. PDOs and OOCs can only test effects on the tumor cells or on reconstituted tumor microenvironments (TMEs) because the rest of the TME, including the immune TME, is compromised during the process of tissue growth in culture. In contrast, microdissected tumor tissues (µDTs), e.g., minced tumor “spheroids” or “ex vivo tumor fragments” tested directly in culture without passaging, preserve key features of the native TME. Though lack of expansion in culture leads to lower throughput, maintaining an intact TME critically enables more clinically-relevant cancer disease models, empowers drug evaluation for the next generation of combination therapies and immunotherapies, and helps deploy more effective personalized oncology approaches. The Folch and Gujral labs have developed a high-throughput µDT approach in which thousands of regularly- sized µDTs are rapidly dissected from a single biopsy. The tumor (or slices) are mechanically cut into ~400 µm- wide, cuboidal-shaped µDTs (or “cuboids”). The cuboids retain key features of the TME, including vascular structures and immune cells, as revealed by immunostaining, proteomics, and cytokine profiling. Using a custom- made robotic platform, we hydrodynamically “lift”-and-place individual cuboids into 384-well plates to obtain high-dimensional molecular readouts of drug effects and TME composition with proteomics (Villen lab), complemented by standard viability readouts, multi-immunohistochemistry, and cytokine secretion assays. Using cuboids, we have demonstrated TME-dependent cancer treatments, such as immunotherapy by checkpoint inhibition, and proteomics analysis of cuboids that provides a readout of cell type, immune processes, and drug responses. Here we will validate the robotic platform combined with proteomics to test TME-dependent combination therapies on individual cuboids from mouse and human tumors at scale and high depth and will integrate proteomics and functional responses to model therapeutic efficacy and resistance.

NIH Research Projects · FY 2026 · 2026-05

ABSTRACT Understanding how the three-dimensional architecture of the nucleus regulates genomic functions remains a central challenge in cell biology. Nuclear bodies (NBs)—membraneless organelles like nucleoli, nuclear speckles, and Cajal Bodies—play a foundational role in nuclear organization that has long been observed cytologically, but which has been challenging to characterize at the molecular level. NBs are thought to partition the genome into thousands of functionally distinct compartments, spatially controlling core genomic functions like ribosome biogenesis, pre-mRNA splicing, and DNA repair. Dysregulation of this compartmental architecture is a pervasive disease driver implicated in many human pathologies, ranging from neurodegenerative disorders to cancer. Remarkably, these complex and essential structures are often built de novo in response to cellular needs, assembling hundreds of distinct proteins, RNAs, and co-regulated loci over the course of mere minutes. These NB-assembly pathways are orchestrated by RNA molecules—which initiate the assembly process and scaffold the intact compartment—and evidence suggests that these programs can be functionally modulated to meet the distinct demands of different tissue-types. Yet, probing the molecular events underlying these phenomena remains a longstanding challenge, since NB architecture is opaque to most conventional genomics tools (e.g., Hi-C), and it is too dynamic and fragile to survive standard biochemical methods (e.g., pulldown). As a result, the molecular architecture of most NBs, how this architecture varies across cell-types and disease states, and its assembly over time, have eluded characterization for decades. This proposal will address these critical knowledge gaps by utilizing O-MAP—a new RNA-targeted spatial-omics tool—to establish general-use methods for probing NB architecture and dynamics. O-MAP is a high-resolution proximity-biotinylation technique that uses programmable, RNA-FISH-like oligo probes to deliver biotinylating enzymes to a target RNA, in situ. This enables systematic discovery of all factors near that RNA, without complex cell engineering of biochemical fractionation. We propose adapting this "off-the-shelf" proximity- omics tool to probe NB architecture by targeting the RNA scaffolds on which NBs are assembled, using the Cajal Body (CB)–a key disease-relevant NB–as a model. In (Aim 1), we generate a high-confidence reference catalog of CB proteins, transcripts, and genomic loci, and characterize the organization of these components using SIM super-resolution imaging. Parallel experiments in a suite of cell-types will reveal how this molecular architecture is adapted across cellular states and in cancer. In (Aim 2), we elucidate the molecular details of the CB biogenesis pathway, using a drug-inducible CB-assembly system, and applying O-MAP and SIM at time points during assembly. This work will yield unprecedented insight into an important disease-relevant nuclear body and establish a versatile methodological framework applicable to other NBs and a wide range of biological contexts.

NIH Research Projects · FY 2026 · 2026-04

PROJECT SUMMARY Identifying and promoting biomedical research practices, including responsible data stewardship and analysis, that advance broad public health benefit and healthcare equity is a societal priority and central ethical concern for researchers and policymakers. For the genomic data science community, new NIH-supported cloud data sharing and analysis platforms promise to `democratize' data use, enabling a more diverse range of researchers to access large-scale genomic and linked health data and, it is hoped, widen the range of research questions that can be answered using such data. While cloud-based data sharing theoretically promises to widen access to genomic and related biomedical data, because researchers need no longer rely on high- performance computing infrastructure at their local institution, the actual uptake and use of data held by these platforms remains uninvestigated. Nor do we currently understand what investigators from underserved backgrounds and/or underrepresented institutions (whom we refer to collectively here as “underrepresented”) perceive as the most important opportunities for, and challenges to, accessing these new resources. Examining how cloud-based data sharing and analysis platforms enhance the uptake and use of genomic data by diverse researchers and institutions will help these new resources better achieve their promise to promote true data science equity. The overall goal of this project is, therefore, to examine the role that NIH cloud-based data sharing and analysis platforms play in promoting a more diverse range of users and research uses, thereby democratizing genomic data science. Specifically, we will work closely with an Expert Advisory Group to address the following Aims: Aim 1. Describe and critically assess the current impact of NIH cloud-based data sharing and analysis platform availability on patterns of genomic data access and use; Aim 2. Compare the perspectives of different categories of underrepresented data scientists on accessing and analyzing genomic and linked health data on cloud-based platforms; and Aim 3. Convene expert advisors, platform developers, and other interested parties to discuss findings and propose potential approaches to promote more inclusive and equitable cloud-based genomic data access and use. The proposed in-depth, interdisciplinary, mixed methods investigation will generate novel data about the ways that NIH-supported cloud data sharing and analysis platforms are changing the genomic data sciences landscape and provide essential insights into overcoming challenges which may be interfering with the promise of these new data sharing mechanisms.

NIH Research Projects · FY 2026 · 2026-04

PROJECT SUMMARY Many neurodegenerative disorders (NDDs) preferentially affect neurons with long or complex axonal arbors. However, our understanding of this specific vulnerability is limited. Using Drosophila melanogaster as a model system, we identified a genetic pathway regulating neuronal production of the proinflammatory cytokine upd3, an Interleukin-6 orthologue, which drives axon length-dependent presynapse removal by glial cells. Remarkably, ectopic upd3 expression induces axon length- dependent presynapse loss in wild-type neurons, demonstrating that long axons and their connections are intrinsically vulnerable to removal. Our central hypothesis, based on extensive preliminary data analyzing axon length-dependent synaptic phenotypes at the structural, functional and behavioral level is that axon length-dependent degeneration is driven by neuronal stress-induced inflammatory cytokine production and subsequent activation of microglia-like phagocytes that recognize signals produced in a length-dependent fashion on target axons. We rigorously test this hypothesis, defining the features of the upd3 signaling system, identifying and characterizing the phagocytic glia, and defining intrinsic signals underlying the vulnerability of long axons to degeneration. Altogether, our studies will provide fundamental insight into a mechanisms of axon length-dependency in degeneration, addressing a fundamental gap in our understanding of NDDs.

NIH Research Projects · FY 2026 · 2026-04

ABSTRACT This midcareer investigator award in patient-oriented research is intended to provide the candidate, Dr. Paul Drain, MD, MPH; Associate Professor at the University of Washington (UW), with protected time to develop a structured and effective approach for research mentorship. He is Director of Clinical Research for the International Clinical Research Center in UW’s Department of Global Health, and Director of the Clinical Core for the Seattle Tuberculosis Research Advancement Center (Sea-TRAC). His clinical research group has been conducting diagnostic studies and clinical trials to advance rapid point-of-care diagnostics for infectious diseases, including HIV, tuberculosis (TB), malaria, and SARS-CoV-2. His research activities are grounded in clinical epidemiology and implementation science frameworks to evaluate a central hypothesis that improved diagnostic screening and testing methods, including novel point-of-care technologies, can advance clinical care and patient- centered outcomes for infectious diseases. However, the design of novel clinical studies, implementation science frameworks, use of mobile technologies, and development of machine learning and AI-guided algorithms have been rapidly evolving for patient-oriented research in the recent years. His research program and group are supported by 3 R01-funded studies, as well as several grants from the Gates Foundation and industry sponsors. From these ongoing and upcoming studies, he will develop a structured research mentoring program with three mentor-specific aims: (1) to identify and support emerging leaders to pursue patient-oriented research, (2) to develop a structured patient-oriented research mentorship program, and (3) to foster mentee research by facilitating access to exiting clinical datasets and advanced statistical research methods. He will also seek to advance patient-oriented research with three research-specific aims: (1) to define the value of diagnostics when implemented for various infections and indications, (2) to assess the demand and acceptance for using rapid diagnostics in community and home-based settings, (3) to utilize machine learning, AI-guided algorithms, and decision-analytic modeling to advance frameworks and utilization of novel point-of-care diagnostics for screening and testing. Achieving these aims will significantly advance his career and his mentees, while providing important contributions to the field of diagnostics. Expanding his capacity to mentor trainees in using the existing clinical studies will help strengthen the next generation of clinical researchers for global health and infectious diseases. This work will lead to a series of future proposed clinical studies and grant applications that will seek to further advance diagnostic technologies and testing to have a maximal impact on reducing morbidity/mortality for HIV, TB, malaria, and diseases of global importance.

NIH Research Projects · FY 2026 · 2026-04

PROJECT SUMMARY Sindbis virus (SINV) is a mosquito-borne alphavirus with a single-stranded positive-sense RNA genome. SINV is transmitted between mosquitoes and birds which serve as reservoir hosts for the virus but can cause spillover infections in other vertebrate hosts including humans. SINV can be classified into distinct genotypes (G1-G6) which aligns with their zoogeographical distribution. SINV causes frequent epidemic outbreaks of polyarthritis disease in Northern Europe and has also been associated with outbreaks in Africa. Epidemics in both these regions are caused by G1 viruses. SINV is widely distributed geographically but is not associated with epidemics elsewhere in the world. Despite being prevalent in mosquito populations in Australia, the SINV strains in this region (G2/3 and G6) have never been associated with epidemics of polyarthritis disease here, though isolated human cases have been reported, and serological data shows the occurrence of human infections. The Australian genotypes of SINV (G2/3, G6) are significantly divergent from the G1 viruses which cause frequent epidemics, suggesting that genetic differences between these genotypes may explain why G1 viruses have a propensity to cause epidemics but other genotypes do not. Most of the genetic tools available to study SINV are derived from G1 viruses, and there is only a single non-G1 cDNA clone (for the G4 virus XJ-160). There currently exists no molecular clones for studying other genotypes of SINV, including the divergent Australian G2 and G6 viruses. In this R03 we propose to construct cDNA clones for G2 and G6 SINV and characterize the in vitro replication properties of these clones and compare pathogenesis profiles of virus derived from these clones versus characterized G1 strains in a small animal model. We have established a subcutaneous model of SINV infection and shown that replicating virus can be detected in the skin and joints of adult mice, which reflects the pathogenesis observed in humans. Thus, this serves as a good model for examining the genetic determinants that underlie the epidemic potential of neglected SINV genotypes. These tools will be available to the research community and thus aid in further investigations of other key aspects of arbovirus transmission and pathogenesis including virus-mosquito interactions, species-specific determinants of transmission, and viral immunity.

NSF Awards · FY 2026 · 2026-04

This project will advance the understanding of causes and implications of recent extreme sea ice variability in the Antarctic through development of a research and logistical partnership with New Zealand. We focus on the Ross Sea as an area of strategic interest for the US and New Zealand, a major locus of recent variability, and as a key area of significance to global ocean circulation and intact ecosystem food webs, motivating the establishment of the Ross Sea Marine Protected Area (MPA). Understanding drivers of sea ice variability and its implications for this large and remote region requires integration across a range of approaches. This pilot study will integrate deployment and testing of advanced observing technology, modelling, and satellite remote sensing to assess capabilities and strategies for a broader integrated program to understand the drivers and implications of the recent rapid sea ice decline in the Ross Sea. This program seeks to advance capability in key areas, building a strategic collaboration between the United States Antarctic Program and the New Zealand Antarctic Research Program and other international partners, in alignment with the “Antarctica InSync” initiative, supporting coordinated, sustainable research in one of the world’s most logistically challenging environments. This will foster increased collaboration and shared logistics support, and further enhance US leadership in the Antarctic. Insights from this work will help improve predictions of how the Southern Ocean and sea ice both respond to and influence global environmental change. Antarctic sea ice extent has exhibited extreme recent variability, with a modest long term increase culminating in 2015, followed by a dramatic decline in 2016 and record lows in both summer and winter in 2023, although with significant variability over the past decade. These changes in sea ice extent are likely closely related to changes in thickness. The causes of this recent variability and its implications have been identified as a key theme for the international research effort “Antarctica InSync”. This collaborative RAPID project will (1) evaluate advanced and emerging technology that can contribute to an observational network capable of capturing key processes across the Ross Sea, (2) improve and evaluate both satellite and model products with in situ observations, and (3) develop a combined modelling, satellite, and in situ observational strategy to understand these processes. This is centered on capability development through evaluation of techniques in the McMurdo region, leveraging existing programs and logistics. This capability can then be exploited in future projects through widespread deployment of in situ observations, integrated with a refined modelling and satellite observation strategy to address the complex coupled role of various atmosphere-ice-ocean processes in driving sea ice variability. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NIH Research Projects · FY 2026 · 2026-04

Project Summary/Abstract Chronic pain affects a large portion of people with multiple sclerosis (PwMS), impacting their daily activities and overall quality of life. Mindfulness-Based Cognitive Therapy (MBCT) has shown effectiveness in alleviating pain for people with MS; however, there is considerable variation in how individuals respond to treatment. Consistent home practice is hypothesized to be a key factor in producing therapeutic outcomes. However, mastering a new skill in treatment does not necessarily mean that it will translate to real-life situations, and a consistent barrier to treatment success occurs when individuals fail to practice mindfulness in daily life. As a result, there is a significant need to identify barriers and facilitators to mindfulness practice among people with MS undergoing MBCT for chronic pain. Recent advances in mobile technology allow investigators to examine these barriers in close to real time and provide adaptive and timely intervention. This K23 Career Development Award will provide the candidate training in intensive longitudinal and micro-randomized trial design and analysis, acquire proficiency in just-in-time adaptive intervention (JITAI) development, and enhance grantsmanship and scientific dissemination skills with a focus on developing a successful R01 application utilizing pilot data from this project. This new training will be leveraged to advance understanding and engagement in mindfulness practice among individuals with MS participating in MBCT for chronic pain in three integrated steps. Aim 1 will utilize ecological momentary assessment (EMA) to identify barriers and facilitators to mindfulness practice among 80 individuals with MS during 8-weeks of MBCT. Aim 2 will develop a JITAI informed by the EMA data to deliver personalized “nudges” promoting mindfulness practice during MBCT sessions. This phase will also incorporate human-centered design methods and feedback from PwMS to maximize feasibility. Aim 3 will use micro-randomized trial methodology (MRT) to optimize JITAI components and explore preliminary feasibility for 50 people with MS participating in MBCT. All aims will be supported by didactic, experiential, and mentored training in the fundamentals of clinical research through the Department of Rehabilitation Medicine at the University of Washington School of Medicine. Collectively the research and training aims of this project seek to inform and personalize the delivery of mindfulness-based interventions (MBIs) for chronic pain not only in people with MS but also in other populations experiencing pain. This award will equip the candidate with the expertise to independently lead innovative research in MBIs, advance pain management strategies and enhance quality of life for individuals with chronic health conditions.

NIH Research Projects · FY 2026 · 2026-04

Project Summary Neutropenia, defined by abnormally low neutrophil counts, compromises innate immunity and increases susceptibility to life-threatening infections. Although most cases are acquired—resulting from malignancy, chemotherapy, infections, medications, or autoimmune disease—the study of inherited forms, though rarer, offers critical insights into the core mechanisms of myelopoiesis and granulocytic differentiation. Among these, autosomal dominant, heterozygous mutations in ELANE (formerly ELA2), which encodes the neutrophil granule serine protease neutrophil elastase (NE), represent the most common cause of severe congenital neutropenia (SCN) and the primary cause of cyclic neutropenia. SCN presents at birth with lifelong neutropenia, bone marrow maturation arrest, and elevated risk of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). In cyclic neutropenia, neutrophil counts fluctuate between zero and near-normal with a striking 21-day periodicity. Despite their clinical importance, the pathogenic mechanisms of ELANE mutations remain poorly understood, and curative treatment is currently limited to hematopoietic stem cell transplantation. Mouse models fail to recapitulate the human phenotype, highlighting the need for human systems to investigate disease biology. All known pathogenic ELANE mutations result in production of a variant NE polypeptide, which may bypass key steps of proteolytic maturation and mislocalize within developing cells. This project tests the hypothesis that ELANE mutations cause disease by disrupting the spatial or temporal control of NE activity during granulopoiesis. Using isogenic, gene-targeted human induced pluripotent stem cells (iPSCs), the proposed research will: (1) define the spatial and temporal determinants of NE pathogenicity by introducing cis-acting suppressor mutations that disrupt its processing, trafficking, and catalytic activity; (2) determine whether the NE paralogs proteinase 3 and cathepsin G function as trans-acting modifiers; and (3) test whether CD34, a critical hematopoietic surface protein with distinct properties differing between mouse and human, is an NE substrate, and whether cleavage-resistant CD34 variants can restore granulopoiesis in ELANE-mutant cells. These studies will elucidate mechanisms of protease regulation in human neutrophil development, clarify the pathogenesis of both inherited and acquired neutropenia, and identify molecular targets for potential therapeutic intervention. The proposed work aligns directly with the NIH mission to advance understanding and treatment of hematologic and immune disorders.

NIH Research Projects · FY 2026 · 2026-04

Project Summary An emerging model of obesity pathogenesis posits a central role for the inflammatory activation of hypothalamic microglia localized to the arcuate nucleus (ARC, a key brain area for the control of food intake and body weight) in the pathogenesis of diet-induced obesity (DIO), a finding observed in mammalian species ranging from rodents to humans. While microglia activation in the ARC is a known determinant of weight gain in high fat diet (HFD)-fed mice, it paradoxically improves glucose tolerance in DIO, but the mechanisms underlying both of these metabolic effects remain unclear. Herein, we report the novel finding that in mice, DIO induces loss of specialized extracellular matrix (ECM) structures known as perineuronal nets (PNNs) in the same brain area where reactive gliosis occurs. PNNs can powerfully influence the activity of neurons that they enmesh, and in the ARC, a large proportion of AgRP and a subset of POMC neurons are among those enmeshed by PNNs. These neurons are central regulators of energy homeostasis, and their altered function in DIO is strongly implicated in obesity pathogenesis and glucose regulation. Importantly, ablating or silencing microglia reduces Npy and AgRP levels and increases POMC neuron excitability, suggesting a link between microglial activation and ARC neuronal function that promotes weight gain. Furthermore, DIO is associated with loss of hypothalamic PNNs in proportion to the degree of microglial activation, with PNN stability enhanced by interventions that ablate or limit the inflammatory capacity of microglia. Finally, removal of hypothalamic PNNs experimentally causes gliosis, hyperphagia and rapid weight gain with preserved glucose tolerance in rodents, providing strong evidence that microglia and PNNs are linked in a critical mechanism that underlies obesity pathogenesis. Here, we investigate the inter-related hypotheses that obesity-associated microglial activation induces loss of PNN enmeshment of ARC neurons, thereby altering AgRP and Pomc neuron function in ways that promote excess fat accumulation but maintain glucose tolerance. Proposed studies will first quantify the role played by microglia to regulate ARC PNN turnover. We will then 1) determine whether the effect of DIO to induce loss of ARC PNNs depends on microglial activation, 2) identify the roles of both microglial activation and PNN loss in obesity-associated dysfunction of AgRP and POMC neurons, and 3) determine the bidirectional contributions linking ARC PNN loss and microglial activation to DIO susceptibility.