Emory University

NIH Research Projects · FY 2026 · 2026-03

In recent decades, we have gained a deep understanding of brain function in health and disease with the advent of techniques relying on genetic manipulations such as opto- and chemogenetics. These methods allow the isolated investigation of well-delineated cell populations. Although the hippocampus is one of the most extensively studied brain regions, research progress has been severely hindered by the lack of genetic access to hippocampal subfields, thereby restricting the applicability of these trailblazing methodologies. Several adeno- associated virus (AAV) vectors utilizing neuron-type-specific regulatory transcriptional sequences (enhancer- AAVs) were developed recently. We propose to develop hippocampal cell type-specific enhancer-AAV viruses for highly efficient and convenient targeting of hippocampal excitatory cell types by evaluating the potential of several candidate enhancers for neuron-type-specific targeting in the hippocampus using a publicly available hippocampal RNA sequencing (RNA-seq) dataset. First, we will develop enhancer-AAVs for selective targeting of dentate gyrus granule cells. Our preliminary results show highly specific granule cell labeling, which we will leverage to develop cell type-specific optogenetic and chemogenetic virus variants. Second, we will expand these efforts to other hippocampal excitatory cell types: CA3, CA2, and CA1 pyramidal cells and hilar mossy cells. The development of these selective methods will allow the research community to gain unprecedented insight into hippocampal function in healthy and pathophysiological conditions.

NIH Research Projects · FY 2026 · 2026-03

The long-term goal of this project is to understand how loss of progranulin (PGRN) causes neurodegeneration in frontotemporal degeneration (FTD) and neuronal ceroid lipofuscinosis (NCL), commonly called Batten’s disease. FTD and NCL are fatal and currently incurable. FTD and NCL have distinct clinical manifestations but share a causative genetic factor, the GRN gene, which encodes PGRN. PGRN is an 80 kDa secreted glycoprotein composed of 7.5 tandem proteins called granulins. Heterozygous GRN mutations decrease PGRN levels and are a common cause of FTD, the most frequent dementia before the age of 60. Importantly, complete loss of PGRN through homozygous GRN mutations causes the neurodegenerative lysosome storage disease NCL type 11 (CLN11). Thus, PGRN activity is important for lysosome function and brain health, yet the function of PGRN is unclear. Our lab discovered that PGRN localizes to the lysosome, is critical for lysosome homeostasis, and is rapidly processed in the lysosome into 7 individual stable 6-kDa granulins. New preliminary data show that treatment of Grn-/- mice with a single granulin, granulin-4, fully ameliorates neuropathology, lysosome dysfunction, and neuroinflammation. These data lead us to hypothesize that a novel receptor facilities lysosomal trafficking of PGRN and processing into granulins, which function to maintain bis(monoacylglycerol)phosphate (BMP) lipid levels that are necessary for lysosomal lipid catabolism to prevent neurodegeneration. Our team has the expertise and necessary tools to bring clarity to the function of granulins and test this novel hypothesis in three aims. In Aim 1, we will test the ability of each granulin to ameliorate lysosome dysfunction and neurodegeneration. In Aim 2, we will delineate the molecular pathways that traffic PGRN to the lysosome to produce granulins. In Aim 3, we will dissect the molecular mechanisms of granulin function in lysosome lipid metabolism. Completion of these studies will rigorously test the novel hypothesis that lysosomal granulins are the bioactive functional products of PGRN and potential pre- clinical therapeutics for FTD and NCL. Our results will provide clarity into the function of granulins in the lysosome, which has been a key question holding back the field. This project will help uncover how decreased PGRN and granulins cause lysosome dysfunction and neurodegeneration as well as elucidate new therapeutic targets for diseases caused by PGRN deficiency.

NIH Research Projects · FY 2026 · 2026-03

Modified Project Summary/Abstract Section Santiago Arconada Alvarez, MS is an emerging leader in translational research software at Emory University who serves as the Associate Director of the AppHatchery initiative within the Georgia Clinical and Translational Science Alliance (Georgia CTSA) under the direction of Dr. Wilbur Lam, MD, PhD. The core of his productive and successful career as a Research Software Engineer is in the development of digital health platforms to support research projects. He has developed over 11 digital health solutions publicly available in domain areas such as: 1) user-center designed software for patient and provider education in pediatric cardiovascular health (HerHeart), symptom based decision-making in the perinatal period (MAMALOVE), new onset pediatric Type 1 diabetes (TypeU), and pediatric tonsillectomy surgeries (Ready for Tonsillectomy); 2) public health information dissemination with a digital resource for Tuberculosis guidelines (Georgia TB Reference Guide) sponsored by the Georgia State Department of Public Health; 3) improving health access by breaking down language barriers for a broad range of individuals with an easily accessible and quick mobile interpretation tool; 4) modernizing traditional qualitative research methodologies with a first-of-its-kind mobile app (Fabla) to conduct speech-based Ecological Momentary Assessment (EMA) research, increasing adoption and study compliance from participants and streamlining and enriching data collection for researchers. This Research Software Engineer (RSE) award would provide 3 years of funding to deepen his software expertise and enable him to evolve into a leader in translational research software. Specifically, he will focus on 1) enhancing data security and ensuring greater transparency in existing projects to promote reproducible research; 2) integrating advanced analytics to support Principal Investigators’ primary research goals; 3) making his platforms and methods accessible to researchers at other institutions and within the broader research software community; and 4) building capacity in the RSE community by mentoring junior engineers, taking on leadership roles in collaborative initiatives, and championing user-centered design in research. Growing into these areas will cement him as a leader to contribute significantly to NIMH’s mission of transforming our understanding and treatment of mental illnesses through innovative, scalable, and widely available software platforms, ultimately improving mental health outcomes and advancing research.

NIH Research Projects · FY 2026 · 2026-03

PROJECT SUMMARY The Hedgehog (Hh) pathway is a key signaling pathway for vertebrate development and adult tissue homeostasis. Precise control of Hh signaling is necessary as overactivation or suppression of the pathway causes severe developmental pathologies such as medulloblastoma and holoprosencephaly. Despite the need for targeted therapies, treatments to stabilize Hh signaling in disease states remain limited. Thus, uncovering novel regulatory mechanisms of Hh signaling will provide vital information for developing future therapeutic strategies. A key feature of vertebrate Hh signaling is its dependence on the primary cilium, a signaling organelle that serves as a hub for the trafficking and enrichment of Hh components. The ciliary enrichment of components such as SMO, the obligate Hh transducer, promotes activation of the pathway. SMO activation initiates a signaling cascade, resulting in the transport of GLI transcription factors from the cilium to the nucleus to facilitate the transcription of Hh targets. The field has dedicated decades to understanding how perturbations in the cilium impact Hh signaling. However, little is known about how the signal gets relayed from the cilium to the nucleus. My data identifies Importin9 (IPO9), a member of the karyopherin family, as a novel regulator of Hh signaling through an unknown mechanism. Karyopherins are known for their roles in nuclear trafficking in a RAN-dependent manner. However, RAN is also seen at the base of cilia, and karyopherin Importinβ2 is involved in ciliary trafficking, suggesting that other karyopherins may similarly function in ciliary trafficking. IPO9 binds to RAN and localizes to the base of cilia and nuclear periphery, suggesting it’s engaged in nuclear and/or ciliary trafficking. Additionally, IPO9 interacts and shares similar Hh signaling defects with ARL13B, a ciliary GTPase long studied by the Caspary lab. Like ARL13B, IPO9 regulates the Hh pathway downstream of activated SMO in vitro. In vivo, Ipo9 mouse mutants resemble ARL13B null (Arl13bhnn/hnn) embryos as they die embryonically and exhibit Hh-related phenotypes such as smaller embryo size, exencephaly, and craniofacial defects. These findings suggest that IPO9 and ARL13B function together to regulate Hh signaling. ARL13B regulates GLIs, which undergo several translocation and processing steps to become transcription repressors (GLIR) or activators (GLIA). ARL13B uncouples GLI regulation by specifically upregulating GLIA through an unknown mechanism. IPO9 loss does not impact GLIR production but still reduces the Hh response, suggesting that IPO9 may also regulate GLIA, similar to ARL13B. Thus, I hypothesize that during embryogenesis, IPO9 regulates vertebrate Hh signaling via GLIA, potentially as an effector of ARL13B. I will test this hypothesis by combining genetic, molecular, and biochemistry approaches. This work will uncover how IPO9 regulates Hh signaling by exploring IPO9’s relationship with ARL13B and GLIs. My work will identify new transport mechanisms between cellular organelles regulating the Hh pathway, offering potential strategies for targeting dysregulated Hh signaling in disease states.

NIH Research Projects · FY 2026 · 2026-03

PROJECT SUMMARY: Alzheimer’s Disease (AD) is the most common form of dementia worldwide, affecting one in nine people over the age of 65, with the incidence of this debilitating disease projected to increase. Recent evidence suggests that the locus coeruleus (LC) is the first brain region to show tau pathology in AD and undergoes catastrophic degeneration later in the disease. The LC is the brain’s primary source of norepinephrine (NE), a neurotransmitter critical for mood, arousal, stress responses, and cognition. Early dysfunction of the LC is thought to contribute to prodromal AD symptoms such as sleep disturbances and anxiety, while LC-NE neuron loss exacerbates cognitive decline. These findings make the LC a focal point for early detection and progression in AD, but the reasons for its selective vulnerability are unknown. The premise of this proposal is that neuromelanin (NM), a pigment-like substance that accumulates in the LC over a person’s life, contributes to its vulnerability in AD. NM, comprised of catecholamines and their metabolites, melanin pigments, heavy metals, oxidated lipids, and protein aggregates, is thought to initially serve a protective role in the brain by sequestering these toxic species. However, overaccumulation of NM may interfere with cellular machinery and contribute to pathology and degeneration. While most knowledge about the LC comes from rodents, mice and rats do not produce NM naturally, making it difficult to study of NM’s role in neurodegeneration. We and others have reported that ectopic expression of human tyrosinase (hTyr), the enzyme responsible for peripheral melanin production, can drive NM accumulation in the mouse LC, resulting in dysfunction and degeneration. Since catecholamine metabolism, linked to LC activity, is essential for NM formation, changes in neuronal firing rate and NE metabolites may contribute to NM over-accumulation, resulting in neuronal inflammation and cell death. In this proposed project, I will use viral-mediated hTyr expression to induce NM formation in the LC, and test how manipulations in cell activity and NE metabolism impact tau, NM accumulation, neuroinflammation, and cell death. In Aim 1 I will use DREADDs to control LC activity, measure firing rate via electrophysiology, and predict that increasing firing will exacerbate, while decreasing LC activity will ameliorate NM accumulation and toxicity. In Aim 2 I will genetically manipulate monoamine-oxidase-A (MAO-A), the primary metabolizing enzyme of LC NE, to determine if genetic variations in MAO-A activity can impact NM accumulation in the LC. I hypothesize that decreasing LC firing and NE metabolism will ameliorate NM accumulation, neuronal inflammation, and cell death in the LC, while increasing these functions will have deleterious consequences. Completing these aims will determine the functional consequences of NM accumulation at the earliest site of degeneration in AD, facilitating the development of therapeutics.

NIH Research Projects · FY 2026 · 2026-02

Alzheimer’s disease (AD) is a progressive and degenerative disorder of the brain. It is pathologically characterized by the loss of neurons. The key events driving the pathogenesis in AD are not completely understood. MiRNAs are a class of small non-coding RNAs about 22nt long and play a key regulatory role in every cellular process. The first step of miRNA biogenesis is controlled nuclear RNase III enzyme Drosha and its co-factor DGCR8 (Di George Syndrome critical region gene 8), which form the complex microprocessor. It processes primary miRNA transcripts (pri-miRNAs) into a ∼65-80 nucleotide hairpin structure named the precursor miRNAs (pre-miRNAs). Emerging evidence indicates that miRNA biogenesis is subjected to complex regulation. The microprocessor is modulated by recruiting various transient factors to facilitate or attenuate the generation of small subsets of pre-miRNAs under unique conditions. The question of if there are distinct pools of microprocessor that are subjected to unique modulation and regulate a broad spectrum of miRNAs remains open. MiRNAs modulate pathways relevant to the pathogenesis of genetic and sporadic AD. AD is associated with loss of miRNA homeostasis. But the mechanisms responsible for dysregulation of Drosha and miRNA biogenesis in AD remain to be fully illustrated. Promyelocytic leukemia protein (PML) is a well-known tumor suppressor and can function biochemically as a SUMO (small ubiquitin-like modifier) E3 enzyme. It is highly sensitive to oxidative stress. Recent findings show that PML plays a role in the brain and responds to conditions associated with neurodegeneration. However, there are no reports if PML directly regulates miRNA biogenesis and is involved in AD pathogenesis. Our preliminary studies have now identified a new PML- dependent mechanism that potently promotes microprocessor activity. We propose a new concept of SUMOylated Super active Microprocessor (SSaM) and hypothesize that PML SUMOylates Drosha and DGCR8 to form the tricomponent SSaM and promotes robust and broad miRNA biogenesis. Loss of SSaM renders neurons less capable of handling oxidative and AD-related stress and underlies in part the cytopathogenic process in the disease. We will determine biochemically if PML functions as a SUMO E3 to regulate SSaM and miRNA biogenesis in cells; if AD stress targets PML and SSaM to dysregulate miRNA biogenesis and trigger cytopathogenesis in rat primary neurons and in forebrain neurons derived from iPSCs of fAD patients; if inhibition of PML-SSaM axis underlies neurotoxicity in a rat model of AD; and if the levels of PML and SSaM correlate with AD status in postmortem human brains. This study should significantly advance our understanding of the basic process of miRNA biogenesis and provide insights on the loss of miRNA biogenic machinery and homeostasis as a cytopathologic feature of AD.

NIH Research Projects · FY 2026 · 2026-02

Project Summary Sleep disturbances are prevalent among persons living with cognitive impairment, including Alzheimer’s disease and related dementias (PLwD), affecting up to 71% of this population. These disturbances—such as difficulty falling or staying asleep—often lead to nocturnal wakefulness, increasing the likelihood of PLwD leaving their beds at night. Consequently, caregivers must remain alert to provide supervision and assistance. Combined with other caregiving responsibilities, this results in frequent sleep disruptions, fragmented rest, and persistent insomnia-like symptoms. Poor sleep is associated with numerous negative health outcomes, including depressive symptoms, cognitive decline, and a greater risk of earlier residential care placement for PLwD. Despite the widespread impact of sleep disturbances on both PLwD and caregivers, few interventions specifically address both parties, and none fully engage them together in all sessions. Cognitive Behavioral Therapy for Insomnia (CBT-I) is the gold-standard treatment for sleep disturbances, with efficacy comparable to medication. Partnered CBT-I, where partners reinforce strategies like consistent sleep schedules and stimulus control, has shown promise. Guided by the Modified Spielman 3P Model of Insomnia and the Theory of Dyadic Illness Management, we piloted a CBT-I intervention (REPAIR Sleep) delivered via videoconferencing to dyads of PLwD and their caregivers. The intervention was feasible and acceptable, with participation resulting in reduced insomnia symptoms for both PLwD and caregivers. We now plan to conduct a randomized controlled trial with 120 dyads to test the efficacy of REPAIR Sleep (a 5-week, 60-minute CBT-I intervention) compared to an attention control intervention, Healthy Living. The study will: 1) evaluate the immediate and 6-month efficacy of REPAIR Sleep versus Healthy Living on sleep outcomes for each individual in the dyad using the Insomnia Severity Index, actigraphy, and sleep diaries; 2) assess the immediate and 6- month efficacy of REPAIR Sleep versus Healthy Living on psychological outcomes for each individual in the dyad; and 3) examine whether adherence to CBT-I and interpersonal support between PLwD and caregivers mediate improvements in sleep and psychological outcomes for each individual in the dyad. This research addresses the critical need for effective sleep interventions among PLwD and their caregivers. The dyadic approach is innovative, empowering both individuals to improve their sleep while supporting each other in behavioral changes. As the number of PLwD and caregivers continues to rise, demonstrating the efficacy of this program is crucial. Successful implementation and broad accessibility of REPAIR Sleep could significantly improve sleep outcomes and mitigate the adverse effects of sleep disturbances in this population. Additionally, the findings have important public health implications, offering a scalable solution to enhance sleep and well- being among PLwD-caregiver dyads.

NIH Research Projects · FY 2026 · 2026-02

ABSTRACT Obstructive sleep apnea (OSA) is a leading public health problem, with estimates that one in 15 adults in the United States suffer from the condition. It is reported that up to 20%-40% of older adults have OSA. Of concern is that up to 34% of individuals treated with standard of care Continuous Positive Airway Pressure (CPAP) therapy have residual sleepiness despite normalization of breathing during sleep. The risk of death is more than two times higher in older adults with OSA and who struggle with excessive daytime sleepiness. The PI’s completed NIH R00 study determined that lower plasma choline and increased inflammation is associated with sleepiness in individuals diagnosed with OSA. A significant correlation between plasma levels of choline and the antioxidant enzyme Superoxide Dismutase-1 (SOD1), was also identified. Citicoline (a dietary, endogenous nutrient) is an oral choline supplement that is well-tolerated by users. Previous studies in animals have shown citicoline inhibits inflammatory cytokines such as Interleukin-6 (IL-6) and improves SOD1. These findings provide support for our theory that choline supplementation will inhibit inflammation and improve sleepiness. Existing wake promoting medications are limited by their tendency for dependency, adverse side effects, and contraindications of usage in those with cardiovascular comorbidities and in the elderly. Citicoline has the potential to improve residual sleepiness and reduce inflammation, yet this intervention has not yet been explored in the OSA population despite a need for improved symptom management. We hypothesize that the addition of citicoline to standard of care treatment (CPAP) will result in improvements in residual sleepiness and inflammation. We will conduct a 4-week randomized, double-blind, placebo-controlled clinical trial comparing citicoline versus placebo in 120 (60 in each group) individuals aged 55 years and older prescribed CPAP who have residual excessive daytime sleepiness [defined by an Epworth Sleepiness Scale (ESS) score of >=11] despite at least 3 months of effective, adherent CPAP use. Participants will be recruited from the Emory Sleep Center. The first aim is to determine whether the citicoline group shows improvements in residual sleepiness and plasma choline compared to the placebo group from T1 to T2. The second aim is to determine whether the citicoline group has increases in SOD1 levels and reductions in IL-6 compared to the placebo group from T1 to T2. Repeated assessments will consist of sleep, diet, and quality of life questionnaires, 2 nights of the Sleep Profiler PSG2 home sleep device, and 7 nights of wrist actigraphy. Our team has extensive experience with biomarkers, clinical research, and sleep medicine. Positive outcomes from this project will allow citicoline to be used as a new therapeutic to improve residual sleepiness and inflammation, which will lead to a reduction in OSA-related comorbidities and improve the health and well-being of older adults.

NIH Research Projects · FY 2026 · 2026-02

Despite extensive research, the mechanisms through which Aβ aggregates contribute to cellular and tissue dysfunction in Alzheimer’s Disease (AD) are still debated. This debate, centered on mechanisms of toxicity, also extends to other human amyloidoses. Though most efforts have focused on identifying toxic species or conformers (e.g., oligomers, protofibrils, fibrillar conformers) and the effects of these Aβ only assemblies, our latest findings propose an alternative, non-mutually exclusive hypothesis. Based on comprehensive proteomic analyses of human AD and control brains, along with mouse models of amyloid deposition, we have proposed the Amyloid Scaffold Hypothesis (ASH). This hypothesis suggests that the accumulation of numerous proteins, scaffolded by, and dependent on amyloid formation, represents a critical mechanism driving downstream pathophysiology in AD. Unlike traditional views of amyloid assembles as direct toxins, the ASH posits that amyloid-associated protein accumulation underpins disease progression. To explore this hypothesis, we will i) determine the molar abundance of proteins co-accumulating with Aβ in AD and Aβ-depositing mouse model brains and assess whether this correlates with changes in protein solubility ii) investigate the interactions driving protein co-accumulation with amyloid deposits, focusing on Aβ, amyloid, and heparan sulfate proteoglycans and iii) test whether extracellular accumulation of these co-aggregating proteins, in the absence of amyloid, induces downstream pathophysiologic changes like those seen in AD. These studies are highly significant. They will directly test a novel mechanism by which amyloid may mediate pathophysiologic effects and may provide clues as to normal physiologic associations of Aβ. Though focused on AD, this work could also have implications for other amyloidoses. This work integrates data and tools from AMP-AD, TREAT-AD, and MODEL-AD initiatives, and is supported by rigorous findings from published and unpublished studies.

NIH Research Projects · FY 2026 · 2026-02

Project Summary/Abstract Protective humoral immunity is mediated by both long-lived memory B cells (MBC) and antibody secreting plasma cells (ASC). Recently it has become increasingly clear that MBC and ASC are in fact composed of functionally diverse subpopulations that can be distinguished based on unique surface marker expression, tissue localization, and the B-cell receptor (BCR) isotype expressed. During a humoral immune response, naïve B cells (nB) give rise to differentiated subsets, with the ultimate composition of the MBC and ASC pool primarily influenced by the antigen, the involvement of T cells, and the cytokine environment. Given the evidence for increased heterogeneity, it is surprising that we currently lack the genetic tools to further interrogate the complexity, molecular properties, and immunological importance of the known B cell fates. A precise phenotypic analysis of MBC and ASC subsets cannot currently be performed with current Cre-lox mouse models. Cis- regulatory elements (CEs), or enhancers, are DNA sequences that act to promote cell-type and context-specific gene expression programs. These sequences are regulated by epigenetic mechanisms, which act to control the accessibility of CEs to DNA-binding transcription factors. Over the past several years, we have characterized the epigenetic architecture that controls primary humoral immune responses to T cell dependent and independent antigens, integrated newly published datasets defining MBC subsets, and generated new preliminary data defining the CEs of ASC expressing distinct BCR isotypes. These data have revealed specific CEs that are active in defined stages of B cell differentiation, including IgA ASC and extrafollicular (EF)-MBC that arise independently of a germinal center reaction. Therefore, we hypothesize that cell-type specific CEs can be co-opted to provide precise genetic manipulation that enables functional exploration of B-cell subsets. To address this, we propose two aims designed to 1) develop new Cre recombinase tools for genetic manipulation of IgA ASC and 2) map the CEs for EF-MBC that arise during influenza infection and integrate CEs specific for EF-MBC to allow precise genetic editing of this MBC subset. These aims will utilize novel hematopoietic stem cell engineering to rapidly generate chimeric mice expressing genes of interest; therefore, bypassing the need to generate transgenic animals. Completion of these aims will provide a novel set of DNA sequences that allow for MBC and ASC specific genetic manipulation. These tools are critically important begin to derive the biology, molecular properties, and importance of the entire spectrum of B-cell differentiation to humoral immunity. If successful, it also has the potential to redefine how Cre recombinase vectors are engineered and further our understanding of CE biology in B cells and the immune system.

NIH Research Projects · FY 2026 · 2026-02

PROJECT SUMMARY Antiretroviral drug therapy (ART) is the gold standard for HIV therapy for suppressing HIV infection. However, these small molecule drugs cannot eliminate the viral reservoir and thus, ART is a life-long therapy. Broadly neutralizing antibodies (bNAbs) could supplement ART and be used to reduce the viral reservoir through their Fc effector functions. While passive infusion of multiple active bNAbs can suppress viremia after ART is lifted, this strategy still requires the need for multiple infusions to maintain therapeutic concentrations of the bNAbs. We have been using adeno-associated virus (AAV) vectors to deliver HIV bNAbs, SIV bNAbs, and antibody-like inhibitors. AAV vectors provide means for long-term expression of bNAbs at concentrations capable of maintaining viral suppression via a one-time intramuscular administration. One issue that has been plaguing the field, especially in nonhuman primate models, is the development of host anti-drug antibodies and immune responses against the expressed bNAbs. We have recently demonstrated that targeting the immune checkpoint pathway is a promising target to limit the host immune response after vector administration. This work has resulted in consistent expression of two HIV bNAbs in rhesus macaques at concentrations thought to be in therapeutic range to suppress an HIV or SIV infection. Additionally, our work in developing eCD4-Ig, an antibody-like HIV entry inhibitor, has produced promising prophylaxis results in rhesus macaques against SHIV and SIV challenges. Because eCD4-Ig neutralizes all HIV-1, HIV-2, and SIV isolates and no escape mutations have been identified to date, it is a powerful inhibitor to combine with bNAbs for HIV and SIV therapy. Unlike ART, both antibodies and eCD4-Ig can kill infected cells, thus, providing a promising strategy to reduce and eliminate the viral reservoir. Therefore, we hypothesize combining AAV-delivered eCD4-Ig with antibodies would generate a unique viral reservoir upon suppression in the absence of ART, both characteristically and quantitatively. In Aim 1, we will optimize our AAV delivery strategy for multiple SIV antibodies and eCD4-Ig. In Aim 2, we will characterize and quantify the viral reservoir upon suppression when mediated by SIV bNAbs and eCD4-Ig compared to ART. In Aim 3, we will determine whether AAV-delivered SIV bNAbs and eCD4-Ig can increase the rate of viral reservoir decay compared to ART. These results would provide a foundation for AAV-delivered inhibitors as an alternative to ART and move the field closer to realizing an HIV cure.

NIH Research Projects · FY 2026 · 2026-02

PROJECT SUMMARY Sleep irregularity is highly prevalent and linked to downstream adverse cardiometabolic health outcomes, but the upstream drivers of sleep irregularity are not well characterized. Adverse health outcomes associated with irregular sleep timing mirror those linked to shift work, and irregular sleep may represent a driver of circadian misalignment and related disease in the general population. Notably, sleep timing is modifiable and could serve as an inexpensive, non-invasive way to promote health, but further research on environmental factors influencing sleep regularity is required to inform successful interventions. Understanding the environmental drivers and molecular markers of irregular sleep are critical gaps that would aid public health intervention and disease prevention efforts. The recent 2021 NIH Sleep Research Plan highlights research on the effects of environmental exposures on sleep and on epigenetic mechanisms underlying sleep and circadian health as top priorities. Therefore, to address these gaps in knowledge and stated research needs, I propose to apply acquired training in sleep epidemiology, chronobiology, and advanced statistical analysis and epigenetics to: 1) investigate which dimensions of light exposure impact sleep regularity and moderation by factors such as age and sex (K99), 2) develop biological markers of sleep regularity (K99), 3) validate and establish the temporality of resulting findings with prospectively collected data (R00), and 4) expand measurement of light and environmental factors with prospectively collected data (R00). My goal is to establish an independent research program centered around how light and other environmental exposures affect sleep and chronobiology in population health. This proposed study and career development plan logically builds upon my training in environmental health, vision research, and molecular epidemiology, to gain expertise in light data analysis and collection, sleep epidemiology, chronobiology, advanced statistical modeling, and omics integration. With expert mentored guidance provided by Dr. Tamar Sofer, Dr. Susan Redline, and Dr. Frank Scheer, I will establish a unique interdisciplinary research program focusing on the interactions of the light environment and sleep. This award will provide key training in four areas: 1) sleep epidemiology; 2) clinical chronobiology; 3) integration and analysis of high-dimensional light and actigraphy data with omics data; and 4) professional development. This data collected during the R00 phase will also provide a strong foundation for R01 applications. This support provided by this award will allow me to launch a novel independent research program and address inherent gaps in our understanding of the role of naturalistic light exposure on sleep health in the general population.

NIH Research Projects · FY 2026 · 2026-02

It has long been evasive why strictly hepatotropic viruses, such as hepatitis C virus (HCV), have been associated with the generation of delayed antibody responses that are of relatively poor quality to other, more systemic infections. Studies to date investigating antiviral adaptive immune priming within the liver have been hindered by lack of a natural, biologically relevant small animal model of viral infection exclusively restricted to hepatocytes. In this proposal, we will accordingly use the HGV-related rodent hepacivirus (RHV) recently discovered by our team, which possesses several similarities to its genetic relative, including strict liver tropism, conserved replication dependence on miR-122 interaction with the viral 5' UTR, identical genomic organizational structure and polyprotein cleavage pattern, and the propensity to cause chronic infection with fibrosis and hepatocellular carcinoma tumorigenesis. Our preliminary identification of robust antibody-secreting cell (ASC) responses, both total lgG and those targeting the envelope glycoprotein E2, almost exclusively arising within the liver during both human HCV and murine RHV infection, served as the rational impetus for further investigation of how, when, and where such responses are generated. The secondary lymphoid organ (SLO) dormancy accompanying such strong ASC responses within the liver alongside their durable maintenance therein by putative cognate anchoring pairs, many of which are also critical for tethering of long-lived plasma cells (LLPCs) to stromal niches in bone marrow, collectively suggest that the liver may serve as a site conducive to both the local generation and perpetual maintenance thereafter of LLPCs during strictly hepatotropic viral infection. As our recently published findings demonstrate that viral-specific lgG is critical for viral resolution, the development of chronic infection and HCC tumors in its absence suggests that generation of plausibly locally generated humoral responses within the liver at sites of virus-induced tertiary lymphoid structures, hereafter denoted as inducible Hepatic-Associated Lymphoid Tissue (iHALT), likely serve an important functional role. The survival of LLPCs residing in the liver 1.5 years post-clearance in these mice represents a unique scenario in which the liver may also provide a suitable niche for these cells, contrary to the canonical paradigm in which the bone marrow or select SLO circumstances are exclusively capable of fostering such an environment. We propose to mechanistically determine the signaling prerequisites responsible for driving this local, successful antiviral antibody response within the liver (Aim 1) as well as the cues instructing putatively locally derived progenies to be retained directly adjacent to their generative origins (Aim 2). Understanding these processes would significantly enhance our understanding of the relationship between hepatotropic viruses capable of suppressing SLOs in a state of functional dormancy with humoral responses plausibly being housed ectopically at extra lymphoid sites. Further, these studies would likely yield important insights capable of influencing the current paradigm of durable antibody responses in antigen free settings, specifically exploring a potentially novel niche site conducive to LLPC survival within the liver.

NIH Research Projects · FY 2026 · 2026-02

Project Summary The impact of reproductive events on menopause and aging processes is largely unknown. While menopause is part of the aging process, the timing of menopause varies with earlier onset associated with risk of premature mortality. Latina women’s timing and frequency of reproductive events, including puberty, pregnancy, and menopause, differs from that of other racial/ethnic groups. Despite socioeconomic disadvantage, on average, Latina women experience similar or lower risk of adverse birth outcomes compared to non-Hispanic white women. This so called “birth paradox” does not apply to maternal outcomes. Latina women in the US have an elevated risk of primary cesarean, gestational diabetes, and increased risk of developing type II diabetes and heart disease later in life. We propose to examine how reproductive events are associated with biological aging processes and menopause and how social context may modify these associations in a sample of Latina women participating in the Hispanic Community Health Study /Study of Latinos (HCHS/SOL). The HCHS/SOL study is a longitudinal study of US Latinos, representing varied countries of origin, conducted in the US. The planned analyses will be conducted among a random sample of pre-menopausal women at baseline followed over a 12-year period. Leveraging the infrastructure of the HCHS/SOL study, through a brief phone-call, we will collect detailed information on reproductive events, perimenopausal symptoms and timing of menopause. We propose to assay existing blood samples for DNAm and characterize trajectories of epigenetic aging over a 12-year period (three time points) to understand how reproductive events influence timing of menopause and DNAm age in adulthood among Latina women. Uniquely, this design allows us to compare individuals’ DNAm aging pre- and post- reproductive events, a major strength of this proposal. Specifically, we will examine 1): How the frequency, severity and timing of reproductive events (menarche, infertility, pregnancy complications and gynecological disorders) affect menopausal onset and symptoms (N= 2000) and how social context may modify this association; 2) How frequency, severity, and timing of reproductive events impact the rate of epigenetic aging among premenopausal women of late reproductive age followed over a 12-year period to capture the menopausal transition (N=1000) and how social context modifies this association; 3): Use genome wide methylation and functional enrichment analyses we will explore how reproductive events are related to alterations of DNA methylation, prior to and during the menopausal transition (N=1000). Upon completion of this project, our findings will elucidate important epigenetic pathways that will help explain how reproductive events affect aging processes among a population that experiences distinct sociocultural factors.

NIH Research Projects · FY 2026 · 2026-02

PROJECT SUMMARY BCL11A is a zinc-finger transcription factor that has been well-studied in erythroid biology, but evidence for an important role in the brain is beginning to emerge. Patients with heterozygous loss-of-function BCL11A mutations present with clinical features that can include intellectual disability (ID), autism spectrum disorder (ASD), and epilepsy. BCL11A is identified as a high confidence ASD risk gene in the SFARI database, and multiple lines of evidence also support potential roles in the etiology of schizophrenia (SZ) and Alzheimer’s disease (AD). However, the mechanisms that link BCL11A to these clinically challenging disorders are poorly understood. To better understand the neuronal function of BCL11A, we performed a series of preliminary behavioral analyses following the selective heterozygous deletion of Bcl11a from excitatory and/or inhibitory neurons in the mouse brain. Surprisingly, we found that Bcl11a deletion from inhibitory GABAergic interneurons (GINs) resulted in social deficits, hyperactivity, and increased seizure susceptibility. Furthermore, we observed increasing levels of BCL11A expression and physical occupation at predicted binding motifs during differentiation and maturation of GINs derived from human induced pluripotent stem cells (iPSCs). Additionally, we found that GIN-enriched ventral forebrain organoids derived from BCL11A-null iPSCs display differential gene expression signatures that overlap with pathological changes in the prefrontal cortex of postmortem brains of individuals with ASD and SZ. Taking these observations together, we hypothesize that the clinically challenging neurological phenotypes associated with BCL11A mutations likely reflect the specific impact of altered BCL11A function on different classes of neurons, with GINs being particularly vulnerable. We will test this hypothesis through a comprehensive series of in vitro (Aim 1) and in vivo (Aim 2) approaches. In Aim 1, we will identify and compare the gene targets of BCL11A in human iPSC-derived excitatory neurons and GINs. We will also employ single-nucleus (sn)RNA-seq and snATAC-seq along with whole-cell patch clamp electrophysiology and histology to establish the overlapping and distinct roles of BCL11A in human neuron populations. In Aim 2, we will further explore the in vivo function of Bcl11a by determining the behavioral and physiological effects of deleting Bcl11a in a neuron type-specific manner in mice. We will also use a chemogenetic approach to further interrogate GIN subtype-specific contributions to BCL11A disease mechanisms. Our long-term goal is to translate these findings into a better understanding of the role of BCL11A in the brain, which will help guide treatment development for patients with BCL11A dysfunction and other GIN-associated disorders.

NIH Research Projects · FY 2026 · 2026-02

PROJECT SUMMARY Type 2 diabetes (T2D) is a heterogeneous disease with varied clinical characteristics, treatment responses, and complication risks. However, gaps persist in understanding the biological drivers and clinical implications of T2D heterogeneity, limiting the potential to develop personalized and effective approaches to prevention and treatment. Notably, most existing phenotypic classification schemes are based on variables rarely collected in usual care and have derived T2D phenotypes using variables collected only at diabetes onset, greatly limiting practical application. Furthermore, the utilization of genomic data, such as polygenic risk scores (PRS) for T2D phenotypes and complications, offers a unique opportunity to understand the biological mechanisms driving heterogeneous clinical presentations and outcomes of T2D. However, despite the potential of PRS, significant gaps remain. Most studies examining the link between PRS and T2D complications have been studied in European populations, limiting the generalizability of findings to the broader population. Additionally, many existing studies have focused on single time-point measurements, failing to capture the dynamic nature of T2D phenotypes and their progression over time. To overcome these gaps, we will leverage the extensive and nationally representative Kaiser Permanente Research Bank (KPRB) cohort to address T2D heterogeneity in phenotypic presentation and risk of complications through a comprehensive and innovative approach. We aim to identify novel T2D phenotypes using widely available clinical variables from 110,434 individuals across eight U.S. states. By employing advanced data-driven clustering techniques and longitudinal assessment over a mean follow-up of 13 years, we will explore the dynamics of T2D phenotypes over time and with aging, as well as their association with T2D complications. Our study will also integrate polygenic risk scores (PRS) to enhance the precision of phenotype classification and complication prediction, offering insights into the genetic mechanisms underlying T2D heterogeneity. Our aims are to (Aim 1) identify T2D phenotypes and investigate the dynamics of phenotypic allocation with aging amongst members (n=110,434 T2D) of a large nationally representative healthcare delivery system using widely available clinical variables; (Aim 2) examine associations between T2D phenotypes and T2D complications; and (Aim 3) investigate molecular pathways associated with T2D phenotypes and complications. This project will accelerate the progress of translational precision medicine, improve understanding of the pathophysiology of T2D phenotypes, and investigate molecular pathways associated with T2D phenotypes and complications across race, ethnicity, sex, and age groups. This work can inform the development of practical and targeted therapies for improved T2D management and care.

NIH Research Projects · FY 2026 · 2026-02

Project Summary Over 300 million individuals worldwide are affected by developmental disorders. Many such disorders arise from dysfunction of RNA-binding proteins and regulatory factors that play general roles in gene expression but often cause pathology within specific organ systems. An example of a critical RNA processing factor linked to disease is the RNA exosome, an essential and conserved 3’ to 5’ ribonuclease complex, which processes and/or degrades most types of cellular RNAs. Notably, dysfunction of the RNA exosome is associated with human diseases, termed “RNA exosomopathies”, which manifest during development and can result in neurological disorders such as microcephaly, pontocerebellar hypoplasia and motor neuron deficiencies as well as cardiac conduction and rhythm abnormalities which can cause sudden cardiac death. Patients with RNA exosomopathies rarely live beyond childhood, and the diseases currently have no treatments. RNA exosomopathies are typically caused by single amino acid changes in conserved regions of the structural subunits of the RNA exosome complex. The list of RNA exosomopathies continues to expand, highlighting the need to characterize these diseases and uncover disease mechanisms. My proposal will be the first to analyze a series of missense mutations that occur in the EXOSC5 subunit of the RNA exosome to understand how each of these changes similarly or distinctly alters RNA exosome function and leads to disease. I hypothesize that different mutations within EXOSC5 cause distinct functional changes in RNA exosome activity. Because individuals with pathogenic mutations in the EXOSC5 gene show both neurological and cardiac symptoms, I will focus on defining how a series of missense mutations in this gene impact RNA exosome activity and function using a rapid and facile system by modeling these changes in budding yeast. Thus, my studies will test this hypothesis by exploiting the Saccharomyces cerevisiae ortholog of EXOSC5, Rrp46. Due to the evolutionary, functional and structural conservation of the RNA exosome, budding yeast provides a versatile system to characterize functional consequences of changes linked to RNA exosome disease. For these aims, we have generated five rrp46 missense mutations that cause RNA exosomopathies associated with both neurodevelopmental and cardiac pathologies: rrp46-Q86I, rrp46-L127T, and rrp46-L191H (linked to different severities of cerebellar hypoplasia and risk of sudden cardiac death), a new mutant obtained from our clinical collaborators, rrp46-C202L (linked to congenital ataxia), and rrp46-V73K (linked to cardiac abnormalities). Using these models, I will: Aim 1) examine the impact of each mutation on RNA exosome function through a combination of functional assays and unbiased comparative transcriptomics; and Aim 2) examine the impact of each mutation on RNA exosome structural integrity and interactions through subunit co-migration assays and extragenic suppressor screens. Through these aims, my studies will uncover how different RNA exosome mutations impact the complex to cause distinct molecular outcomes and provide me with critical training.

NIH Research Projects · FY 2026 · 2026-02

PROJECT SUMMARY Tuberculosis (TB) is the 2nd leading cause of infectious disease mortality worldwide with ~1.5 million deaths in 2020. A hallmark of pulmonary TB is the propensity to form cavitary lesions in ~30-85% of patients. Cavities provide an ideal environment for Mycobacterium tuberculosis (Mtb) replication, are associated with decreased penetration of antibiotics, and can lead to irreversible lung damage. Importantly, they are associated with poor clinical outcomes including acquired drug resistance and treatment failure. Cavities develop from progression of necrotic lung granulomas; however, mechanisms underlying their formation are not clear. Improved understanding of the inflammatory responses that drive tissue necrosis and the ability of antibiotics to achieve therapeutic concentrations within necrotic granulomas are needed to 1) identify targets for host directed therapies (HDT) that can limit tissue damage and 2) to optimize antibiotic regimens. Utilizing innovative methods in imaging and spatial multiomics, we will map the distribution of transcriptional pathways and biomediators associated with human necrotic granulomas and cavities and of newly implemented anti-TB drugs in such lesions with an overall goal of providing critical new data to improve TB treatment The long term objective of this research is to provide data to guide development of a tandem therapeutic approach of optimizing anti-TB drug regimens based on their ability to reach bactericidal concentrations in all lesion areas combined with host-targeted therapies to limit pathologic inflammation. The specific aims of this proposal are to (1) identify the host metabolic and lipid phenotypes associated with each tissue region of human necrotic lung granulomas; (2) utilize spatial transcriptomics and targeted imaging to identify pathological programs associated with tissue necrosis in necrotic granulomas; and (3) utilize target site pharmacokinetics (PK) and PK modeling to enhance understanding of newly implemented anti-TB drugs. The aims of this project will be achieved by enrolling a unique cohort of patients with pulmonary TB undergoing adjunctive surgery and subsequent study of their resected lung lesions. Scientific methods employed to carry out our aims include the use of enhanced MALDI-2 mass spectrometry imaging (MSI), laser capture microdissection (LCM) to isolate targeted granulomas regions for high-resolution metabolomics, lipidomics and drug concentration assays, and novel spatial transcriptomics and advanced data analytic methods to integrate spatially resolved multi-omics data sets and model target site PK data. This proposal will directly address key priories in the TB research agenda including attaining a better understanding of the determinants of M. tuberculosis control in granulomas and how anti-TB drugs localize and penetrate into granulomas and cavities. Specific goals of the proposed work are to identify host inflammatory pathways that can be exploited for host-directed therapy and to define tissue penetrating properties of key drugs used for drug-resistant TB to optimize drug regimen design for clinical trial testing and treatment.

NIH Research Projects · FY 2026 · 2026-01

PROJECT SUMMARY The sympathetic nervous system contributes to organismal stability including via vasomotor control of blood flow by regulation of activity in somato-sympathetic postganglionic neurons (SPNs) - to skin for thermoregulation, and to muscle to meet its changing metabolic demands. Command centers in the brain regulate sympathetic drive via descending projections to thoracolumbar spinal cord sympathetic preganglionic neurons that exit to recruit the SPNs that control end-organ function. Spinal cord injuries (SCIs) that interrupt projections from brain sympathetic command centers may partially or completely impair sympathetic homeostatic modulation of target organ function. This leads to a variety of dysautonomias. For example, people with high-level SCIs have little ongoing below-injury sympathetic activity to skin and muscle, and this impairs thermoregulation and muscle function, respectively. In contrast, individuals with more incomplete or lower-level SCIs may have abnormal skin/muscle sympathetic activity. There is increased recognition that electrotherapeutic strategies like epidural spinal cord stimulation (SCS) may recruit SPNs and improve autonomic function after SCI. However, the clinical literature on SCS-based modulation of autonomic dysfunction after SCI is limited and without large-scale randomized trials. Given the variety of protocols used, variability in SCI patient status, and magnitude effort to undertake such studies, it is timely to develop rigorous animal models using clinically analogous SCS to better understand neuromodulation of autonomic function after SCI to help instruct clinical trials. (1) We developed an in vivo approach that incorporates a modified form of microneurography to undertake the first recordings of somatic SPN activity in mice and are now capable of capturing SPN activity from several hindlimb skin/muscle nerves while simultaneously monitoring changes in hindlimb blood flow regulation with Laser Doppler Flowmetry (LDF). (2) We propose to pair this with SCS-based neuromodulation using scaled electrode parameters to deliver clinically analogous stimulus paradigms to study their capacity to modulate motor/skin SPN activity and blood flow. Simultaneous capture of blood pressure, heart rate, respiratory rate and motor activity will provide important insight into SCS modulation of interrelated to physiological parameters. Experiments will characterize and compare the effects of clinically analogous SCS on SPNs and vasomotor function in naive and two SCI mouse models: (i) the T2 transection model with autonomic dysreflexia / body temperature instability, and (ii) the T10 contusion model with neuropathic pain. In sum, we have developed important methodological innovations in an adult mouse model system that provide a powerful exploratory testing ground to study SCS modulation of skin and muscle SPN activity after SCI.

NIH Research Projects · FY 2026 · 2026-01

Resting state functional magnetic resonance imaging (rs-fMRI) contains a wealth of information about the large-scale structure of intrinsic neural activity in the brain and is widely used to study alterations in neurological or psychiatric disorders. Our prior work demonstrates that intrinsic brain activity is dominated by a few whole- brain spatiotemporal patterns that occur repeatedly over time, but little is known about the mechanisms that coordinate these patterns and therefore about how altered patterns in brain disorders should be interpreted. The spatiotemporal patterns exhibit features that are undetectable with time-averaged analysis methods (e.g., functional connectivity) and which may provide important insight into underlying neurophysiology. Three prominent features in need of explanation are sparse instances of strong transient network activity; variability in the amplitude of the rs-fMRI signal across brain areas and over time; and propagation along the cortex that happens concurrently with network interactions. We have developed an innovative method for simultaneous wide-field optical imaging (WOI) and rs-fMRI that will allow us to test potential explanations for these features of intrinsic activity. WOI can detect fluorescence from activity in specific types of cells over the entire cortex, obtaining images of spatial patterns rather than the localized measurements obtained with electrophysiology. Functional connectivity has been observed in WOI of excitatory and inhibitory activity, suggesting that transient network activation patterns of both types of neurons may underlie the strong transient activations observed with rs-fMRI. Aim 1 utilizes simultaneous rs-fMRI and WOI of excitatory and inhibitory neurons to determine if the transient patterns of activity are common and synchronous across modalities. Aim 2 uses the same method to investigate the relationship between the amplitudes of excitatory and inhibitory activity and the amplitudes of the rs-fMRI fluctuations. Finally, we hypothesize that signal propagation is mediated by astrocytes, which have been shown to give rise to traveling waves. Aim 3 applies simultaneous rs-fMRI and WOI to determine the role of astrocytes in the propagation of signal across the cortex. This proposal will make strides toward understanding the coordination of intrinsic brain activity, which is altered in nearly every psychiatric and neurodegenerative disorder. The proposed experiments provide insight into these alterations for the purposes of diagnosing, evaluating, and treating dysfunction in the brain. The knowledge gained about the large-scale organization of brain activity will help to bridge the gap between fundamental studies of activity in local circuits and the whole-brain activity detectable with noninvasive imaging techniques. As experiments proceed, we will further refine the cutting-edge technologies that we have developed for multi-modal WOI and rs-fMRI studies, and we will make the methods and the resulting data freely available.

NIH Research Projects · FY 2026 · 2025-12

No change from the original submission.

NIH Research Projects · FY 2025 · 2025-11

Project Summary Advancements in cancer treatment are enabling breast cancer survivors to live longer, highlighting the need for more research on their ongoing needs after chemotherapy. By 2030, there are expected to be 4.9 million breast cancer survivors in the United States (US). Black women, in particular, face significant differences in breast cancer outcomes compared to other racial and ethnic groups. For example, Black women are frequently diagnosed at later stages, are twice as likely to develop aggressive cancers such as triple-negative breast cancer, which necessitates chemotherapy treatment, and have a 40% higher mortality rate compared to White women. Chemotherapy-induced peripheral neuropathy (CIPN), can be a debilitating side effect following treatment among breast cancer survivors. CIPN symptoms, including numbness, pain, and balance issues, can impede activities of daily living, substantially lower the quality of life, and lead to psychological distress and social isolation among patients. Limited research exists on CIPN presentations among Black breast cancer survivors. Understanding CIPN's impact on treatment decisions and quality of life for Black patients is important to ultimately reducing symptom burden and improving outcomes among survivors. Data on CIPN symptoms, severity, and treatment outcomes are needed to inform clinical interventions and improve patient care. To examine the impact of CIPN on Black breast cancer survivors, this proposed cross-sectional survey study aims to determine CIPN characteristics and severity among N=125 early-stage (stage I-III) Black breast cancer survivors following chemotherapy at a large urban academic medical center in the Southeastern US. Aim 1 will identify CIPN symptoms and severity using patient-reported outcome measures. Aim 2 will examine associations between CIPN severity and physiological, psychological, and social factors. Aim 3 will characterize the occurrence in treatment outcomes, such as chemotherapy dose reductions, dose delays, and treatment discontinuations. This study will illuminate CIPN's impact among Black breast cancer survivors, informing the design of future longitudinal research and interventions to reduce CIPN's impact and improve treatment outcomes. During the conduct of this fellowship, the applicant will pursue a rigorous training plan, under the supervision of an interdisciplinary team of mentors, to cultivate the skills needed to become and independent researcher. This study will provide the initial data to develop a longitudinal cohort of Black breast cancer survivors experiencing CIPN. The proposed fellowship aligns with the National Cancer Institute and the National Institute of Nursing Research’s strategic plans to train the next generation of cancer researchers and strengthen the cancer workforce while reducing symptom burden and optimizing care outcomes among breast cancer survivors.

NIH Research Projects · FY 2025 · 2025-11

Project Summary Capsid assembly is an essential step in production of an infectious herpesvirus, yet little is known on how the process begins and the protein oligomeric states and intermediate interactions required to complete the final mature capsid. Disruptions in capsid assembly result in aberrant capsids unable to assemble or package viral DNA, resulting in noninfectious virus. The major proteins involved in herpesvirus capsid assembly are generally conserved across alpha, beta, and gammaherpesvirus subfamilies which provides an opportunity to develop pan-herpesvirus therapeutics. Yet to date, little has been done to capitalize on this process; furthermore, most capsid assembly research focuses on alphaherpesvirus, HSV-1. This proposal focuses on understanding capsid assembly of gammaherpesvirus, Kaposi sarcoma herpesvirus (KSHV), the leading cause of cancer in HIV positive individuals. I will develop an in-vitro capsid assembly assay to monitor capsid kinetics and oligomeric states required for capsid nucleation and maturation. I hypothesize KSHV capsid assembly is a highly dynamic process requiring multiple conformations of capsid protein intermediates to generate a capsid capable of packaging a large DNA genome. I will purify KSHV capsid proteins via baculovirus expression and systematically determine the proteins required for capsid formation and kinetics via dynamic light scattering and negative stain electron microscopy. In addition, I will evaluate the oligomeric states of capsid proteins individually and protein intermediates to determine 1. The proteins required for capsid nucleation and 2. How KSHV scaffold oligomerizes to produce unique B-capsid morphologies. I further hypothesize that the divergence of SCP between subfamilies is a result of variations in the capsid assembly pathway. For example, it is thought SCP is not required for alphaherpesvirus capsid assembly but is required for gamma and betaherpesviruses. I hypothesize SCP is required for efficient C-capsid assembly, as loss of SCP results in decreased infectious virus and C-capsid formation in alpha, beta, and gammaherpesvirses; however, the exact mechanism is unclear and seems dependent on cellular environment. I will use the in-vitro capsid assemble assay and live virus mutagenesis to study the function of SCP in capsid maturation. I will utilize previously generated KSHV SCP null viruses to quantify capsid structural integrity with atomic force microscopy to determine at what stage capsid assembly stalls, as well as the role of phosphorylation on SCP’s function. These aims will highlight the similarities and difference between alpha and gammaherpevirus viruses, providing the evidence required for inhibitor development and a scalable in-vitro assay for testing inhibitors. I will develop a robust skillset in biophysical techniques which coupled with my expertise in molecular virology will allow me to successful complete these aims and develop the skills required to run my own independent research lab.

NIH Research Projects · FY 2025 · 2025-11

PROJECT SUMMARY Streptococcus pyogenes (Group A Streptococcus, GAS) is a gram-positive obligate human pathogen and a significant public health burden. GAS causes diverse infections, ranging from relatively mild skin (impetigo) and throat (strep throat) infections to severe infections such as necrotizing fasciitis (“flesh-eating disease”) and streptococcal toxic shock syndrome. GAS strains are divided into more than 200 M types based on the variable surface protein M, as well as 9 fibronectin binding, collagen binding, T-antigen (FCT) genetic region types based on their surface pili. Some strains are specifically associated with either skin or throat infections, while others can infect either tissue. Tissue tropism is associated with emm genes and FCT genetic regions, but the precise molecular determinants for tissue tropism are unknown. This work will study host and bacterial determinants for GAS adhesion to skin cells. Additionally, keratinocytes trigger pyroptosis, a programmed cell death, in response to intracellular GAS. This work will also examine the effect of keratinocyte pyroptosis on GAS adhesion, and whether this contributes to infection mitigation. I hypothesize that keratinocytes vary in their exposure of targets for GAS adhesins throughout their differentiation and death, and that this consequently impacts GAS invasion of the skin. Aim 1 will examine GAS adhesion to keratinocytes and identify whether differentiation and death of these cells impact GAS adhesion. Aim 2 will reveal GAS adhesion factors using transposon screening to identify putative genes encoding adhesion determinants in GAS. These will be validated with genetic knockout and complementation experiments. The mentor for this F31 proposal, Christopher LaRock, has extensive experience studying pyroptosis resulting from GAS infection. This work will build on this discovery to identify factors influencing how mild infections can turn severe, determinants of infection resistance, and provide training for the PI Jacob Sherman in techniques of modern molecular Koch’s postulates for a research career in human health.

NSF Awards · FY 2025 · 2025-11

Cells undergo surprising biological changes in microgravity. Under these conditions, cells alter their activities and the structure of their internal “skeleton,” known as the cytoskeleton. This is remarkable because the force of gravity on a single cell in microgravity is very small—roughly one million billionth the weight of a paperclip—and it is not clear how cells sense such tiny changes. This project tests the idea that the cytoskeleton and the proteins that anchor it to the outside environment act as “gravitational sensors.” To test this idea, the team will use an ultra-sensitive molecular force sensor to measure the tiny pulling forces that cells exert on their surroundings through adhesion receptors and see whether those forces change when gravity is altered. Success will enable precise measurements of cell forces aboard the International Space Station (ISS) and reveal fundamental mechanisms by which cells "feel" microgravity. This project investigates how microgravity affects integrin-mediated mechanotransduction, the cellular process by which mechanical forces are converted into biochemical signals. Integrins are transmembrane receptors that couple the extracellular matrix to the cytoskeleton and generate forces critical for cell adhesion, migration, and signaling. Prior work has shown that microgravity alters focal adhesion dynamics and cytoskeletal organization, but the underlying force changes and their signaling consequences remain unclear. To address this, the team will develop and deploy molecular tension fluorescence microscopy probes based on DNA hairpins and duplexes to quantify integrin forces under microgravity aboard the International Space Station. These probes provide piconewton-scale force sensitivity and enable long-term preservation of force signals in fixed samples. Ground-based and ISS-exposed cells will be cultured on force-calibrated substrates, fixed in orbit, and returned for post-flight super-resolution imaging. Using a multiplexed method developed by the team, Points Accumulation for Imaging in Nanoscale Topography or DNA-PAINT, the team will map the spatial distribution of force transmission and associated mechanotransduction proteins such as vinculin and YAP/TAZ. The project aims to (1) determine the minimum force required to activate integrin signaling under microgravity, (2) quantify integrin force profiles using reversible and irreversible DNA probes, and (3) characterize nanoscale focal adhesion organization in microgravity-exposed cells. This ISS-based study will uniquely isolate gravitational effects on force signaling, enabling high-resolution mechanistic insights into how cellular mechanics respond to changes in the external environment. The outcomes will advance both space biology and mechanobiology, informing therapies for diseases involving disrupted mechanotransduction. 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.