Baylor College Of Medicine

NIH Research Projects · FY 2026 · 2026-06

Strongyloidiasis (causative agent Strongyloides stercoralis) is a neglected tropical disease that is often asymptomatic but causes severe morbidity and mortality when the infection becomes disseminated in periods of host immunosuppression. Due to the auto-infective portion of the S. stercoralis lifecycle, infections can persist for decades, long after a person has left an endemic area. Although strongyloidiasis is not considered endemic across the United States, places in the southern US with subtropical climates, such as Texas, can support the S. stercoralis lifecycle; therefore, continued transmission can occur. Adequate screening and prompt treatment of asymptomatic chronic strongyloidiasis will prevent the morbidity that disseminated strongyloidiasis carries. Still, cases are likely missed due to a lack of symptoms and suboptimal screening. Wastewater-based epidemiology has recently been leveraged during the COVID-19 pandemic for disease surveillance independent of health- seeking behavior, making it a powerful tool to assess strongyloidiasis, which is often asymptomatic and likely underdiagnosed. The long-term objective of this project is to understand the epidemiology and risk factors of strongyloidiasis in the greater Houston metropolitan area so that public health efforts may be directed towards the timely detection and treatment of at-risk populations. We will achieve this objective by completing the following aims: 1) Determine chronic strongyloidiasis prevalence and associated risk factors in a population seeking healthcare at a safety-net hospital system in Houston, TX, and 2) Identify areas in the greater Houston area with S. stercoralis presence using wastewater-based epidemiology. The innovation of wastewater-based epidemiology in the novel area of strongyloidiasis will be bolstered by a rigorous epidemiological study and risk-factor analysis. Additionally, this project will be innovative in its combination of improved diagnostic testing compared to standard of care. In aim 1, patients seeking healthcare at two primary care clinics in a safety net hospital system in Houston, Texas, will be approached for enrollment. Participants will answer a risk factor questionnaire and undergo blood and stool testing for strongyloidiasis. A risk map will be generated from neighborhood-level variables. In aim 2, wastewater samples from 16 wastewater treatment plants in Houston will be tested for S. stercoralis, and a spatial analysis will be conducted to determine if strongyloidiasis positivity coincides with high-risk areas on the risk map. By completing this project, the candidate, Dr. Megan Duffey, will develop essential skills in advanced epidemiological study design, statistical modeling, geospatial analysis, and science communication and advocacy. With these skills, she will create an R01-funded laboratory studying emerging neglected tropical diseases across the southern US. This work will be completed in the supportive research environment at Texas Children’s Hospital Division of Pediatric Tropical Medicine and Baylor College of Medicine’s National School of Tropical Medicine under the mentorship of Dr. Sarah Gunter and Dr. Peter Hotez.

NIH Research Projects · FY 2026 · 2026-06

ABSTRACT Autism is a highly heritable neurodevelopmental condition, and males are over-represented in autism diagnoses. The X chromosome is enriched for genes associated with autism, suggesting it may contribute to the observed male bias. Loss-of-function coding mutations within these genes are often lethal in males, but females experience monogenic forms of autism. It is then possible that mild mutations within these genes are sufficient to cause autism in males but spare mosaic females. Males with idiopathic autism are enriched for maternally inherited noncoding mutations in cis-regulatory elements (CRE) proximal to these genes. The broad objective of this proposal is to characterize these X-linked CREs and autism-associated mutations found within them. MECP2 is a dosage-sensitive gene where loss- or gain-of-function mutations cause neurological disorders. Although MeCP2 levels are tightly controlled in typical individuals, the mechanisms by which its CREs, such as the promoter, control gene expression remain unclear. There are at least four mutations within the MECP2 promoter that are maternally inherited and segregate with autism in males. Using CRISPR-Cas9 technology, these mutations will be independently edited into the endogenous MECP2 promoter in human iPSCs (AIM 1). After differentiating these iPSCs into neurons, these mutations will be evaluated for their impact on MeCP2 levels and two representative target genes. For mutations that significantly alter MeCP2 levels, deep RNA sequencing will determine the effects of these mutations on the molecular phenotype of neurons. This dosage sensitivity could extend past MECP2. There are thousands of mutations in male autism probands that are inherited from the mother and localize to 197 different X-linked CREs in open chromatin in excitatory neurons. A majority of these CREs are proximal to 57 different X-linked genes known to cause neurological disease. Using a massively parallel reporter assay, these mutations will be functionally assessed in an unbiased, high-throughput screen (AIM 2). Downstream analyses will determine which genes and which specific regions are most impacted by autism-associated noncoding mutations. The top-ten autism-associated mutations that disrupt CRE activity will then be validated using a luciferase reporter assay. The overall impact of this proposal is to broaden the spectrum of known mutations that cause autism, addressing some of the missing heritability of autism. Additionally, by studying 197 X-linked CREs, this proposal will provide insight into the regulation of 57 separate X-linked genes known to cause neurological disorders, and it will provide a framework for investigating noncoding mutations. These results will enhance the current understanding of noncoding mutations and how they contribute to neurological disease.

NIH Research Projects · FY 2026 · 2026-06

ABSTRACT A molecular cause cannot be identified for most cases of congenital diaphragmatic hernia (CDH) and/or cardiovascular malformations (CVMs) due to an incomplete understanding of the genes that cause these common, life-threatening birth defects. Low-penetrance genes and unique variants are important sources of missing CDH/CVM heritability. They can be difficult to identify in conventional human genetic studies but are often essential for normal diaphragm and cardiac development as demonstrated in their associated mouse models. In this application, we will identify novel CDH/CVM low-penetrance genes and unique variants and determine the morphogenetic and molecular mechanisms by which they cause these defects. This will be accomplished using an innovative gene discovery pipeline that we have used to identify 52 genes and variants that cause CDH/CVM and other congenital anomalies in the past 5 years. In Specific Aim #1, we will identify and prioritize low-penetrance CDH/CVM genes and unique CDH/CVM-causing variants using a machine learning approach. We will use data from >3,000 individuals to identify novel CDH/CVM genes and unique variants. In some cases, existing data will be sufficient to prove that a candidate gene or variant is causative as was the case for 11 CDH/CVM genes that we identified in proof of principle studies. If current data are insufficient, we will use a machine learning approach to prioritize candidate genes for in-depth searches for additional CDH/CVM cases in humans (Aim #1) and CDH/CVM screening in a representative mouse model (Aim #2) as a means of confirming their association with CDH/CVM. In Specific Aim #2, we will screen up to 20 high-priority candidate genes and variants for CDH/CVM in mouse models. These studies will provide strong corroborating evidence of an association between candidate genes and unique variants and CDH/CVM. We will screen for CDH/CVM in existing mouse lines using a high-throughput micro-CT pipeline that we have previously used to identify CDH/CVM in mouse embryos. If a representative mouse line does not exist or is lethal prior to the completion of diaphragm muscularization and heart development (<E16.5), we will generate new mouse models for screening using advanced and novel techniques, including prime editing and N1 embryo screens. In Specific Aim #3, we will determine the morphogenic and molecular mechanisms by which select variants and genes contribute to the development of CDH/CVM. These studies will leverage mouse models for two CDH/CVM genes, CHAMP1 and WNT4, that were previously identified though our gene discovery pipeline and were subsequently shown to cause high-penetrance CVM and CDH in mice, respectively. The morphogenic assays we will use are well established and our proposed molecular studies include cutting-edge Multiomic snRNA-seq and snATAC-seq evaluations. The results of these studies will have an immediate impact on our ability to molecularly diagnose individuals with CDH/CVM and will lay the foundation from which new preventative and therapeutic interventions for CDH/CVM can be developed.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY/ABSTRACT Langerhans cell histiocytosis (LCH) is an inflammatory myeloid neoplasia characterized by lesions including pathogenic CD207+ dendritic cells among an inflammatory infiltrate. The median age at diagnosis is 30 months, and upfront chemotherapy fails in ~50% of patients resulting in multiple relapse events for 40-50% of cases and disease progression associated with potentially fatal progressive neurodegeneration (LCH-ND). Sequencing studies in small cohorts have described >50 somatic mutations in >30 genes in non-MAPK and MAPK pathways, with activating mutations in MAPK pathway genes identified in ~80% of LCH lesions, including BRAFV600E in 45- 65%. However, a driver somatic mutation goes unidentified in ~20% of LCH tumors. There is a “Misguided Myelomonocytic Precursor Model” in which persistence of disease reservoir as well as cell of origin determine extent of disease and clinical risks. However, this model does not address inherited germline genetic effects in LCH. Therefore, we conducted the first genome-wide association study of LCH and identified a SMAD6 variant associated with increased risk. Growing evidence suggests that other germline components like de novo mutations (DNMs) may contribute to a substantial portion of the heritability in complex genetic diseases not detected using GWAS methodology. DNMs play a role in childhood immune dysfunction disorders and genetic syndromes due to mutations in BRAF providing evidence DNMs may also contribute to LCH risk. These findings, in conjunction with our GWAS, support the investigation proposed herein to more clearly define germline genetic effects on LCH risk and adverse LCH outcomes. A critical initiative of this funding mechanism is to analyze large- scale genomic sequence data from pediatric cancer case-parent trios generated through the Gabriella Miller Kids First (GMKF) Research Program. Therefore, the objectives of this R03 application are to identify germline components associated with LCH risk and genomic regions associated with LCH somatic mutational profiles and adverse outcomes using data from 191 case-parent trios sequenced by GMKF. Our central hypothesis is that germline and somatic genetic effects impact LCH pathogenesis and ultimately treatment response. To test this hypothesis, we will: 1) perform a secondary analysis of germline WGS data generated from 191 LCH case-parent trios to more fully elucidate the impact of germline genomic factors, including patterns of inheritance and the role of DNMs, in LCH; and 2) determine LCH germline prognostic markers by leveraging paired germline WGS tumor WES data to test the association between germline variation in key pathways (e.g., TGF-β, BMP, SMAD) and the most common somatic mutational profiles (e.g., BRAFV600E, MAP2K1) in 109 cases with paired data available for assessment. We will also explore whether identified germline variation is associated with i) time to first relapse/disease progression event or ii) time to first LCH-ND event. Successful completion of the proposed aims may (1) improve genetic risk prediction for patients who develop LCH, (2) identify novel therapeutic targets for LCH, and (3) uncover novel mechanisms that may inform the pathogenesis of other MAPK-driven malignancies.

NIH Research Projects · FY 2026 · 2026-06

ABSTRACT This project aims to revolutionize genome annotation by creating new technologies to detect and annotate genomic features currently hidden within intergenic regions. Intergenic features are underexplored and often overlooked by popular genome annotation software despite their vital importance to genome functioning. For example, existing automatic annotation programs miss small proteins due to minimum size cutoffs and are unable to detect non-coding RNAs that are unrepresented in curated databases. These omissions leave the appearance of empty intergenic space that, in fact, contains genomic features. The problem of incomplete annotations is particularly acute for prokaryotic genomes, which are immensely diverse and heavily reliant on automated annotations. This proposal seeks to overcome current limitations, such as the difficulty of detecting ambiguous or rare features, by leveraging machine learning, comparative genomics, and new methodologies for identifying non-coding RNAs, small proteins, and regulatory elements. The proposed technologies will not only improve the accuracy of genome annotations but also enable the discovery of new genomic features that could have significant implications for biomedical research, including the identification of new drug targets. In Aim 1, we will develop a program for finding protein coding genes in prokaryotic genomes that draws upon novel signatures of true genes to improve accuracy over existing methods. In Aim 2, we will identify undiscovered non-coding RNAs by leveraging machine learning with creative signals that differentiate non- coding RNAs from intergenic space. In Aim 3, we will apply comparative genomics methods to clarify the probable function of enigmatic non-coding RNAs. Collectively, these technologies will shed light on unannotated intergenic space and democratize genome annotation by providing an advanced software for comprehensively annotating a broader range of organisms.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY (See instructions): Coronary artery disease is associated with greater atherosclerotic burden, including coronary artery calcifications (CAC). Coronary artery calcification (CAC) poses a significant challenge for completing percutaneous coronary interventions (PCI). CAC reduces vessel compliance and increases the complexities of stent deployment, stent expansion1, balloon expansion2-5, and results in uneven drug distribution6- 8. Specifically, reduced vessel compliance prohibits stent delivery and reduces the ability of deployed stents to expand, or causing "stent regret", resulting in stent failure through either restenosis or stent thrombosis. Novel therapeutic technique with improved safety and efficacy, as well as an invasive diagnostic and monitoring tool which can provide cross-sectional tissue anatomy and physiology for valid, reliable outcome measures will advance clinical management of CAC. The objective of this proposal is to develop novel metasurface optical guidewires for therapeutic applications to CAC capable of being guided by multimodal imaging modalities. this research aims to design and manufacture sub-millimeter meta-surface optics for optical guidewires, develop optimized PCI workflows for laser-induced intravascular lithotripsy, and evaluate the long-term treatment efficacy of metasurface optical guidewire-based PCI therapies in preclinical animal models. Successful completion of these aims will lead to the development o innovative devices and procedures that can significantly improve PCI outcomes in patients with calcified coronary arteries, reducing complications and enhancing patient care.

NIH Research Projects · FY 2026 · 2026-06

PROJECT SUMMARY Precise regulation of cell fate specification during early embryogenesis is essential for proper tissue and organ formation, and its disruption leads to congenital malformations. However, the gene regulatory pathways controlling these early developmental decisions—particularly in humans—remain poorly understood. This proposal investigates a novel, primate-specific mechanism of cell fate control mediated by the dual-function DNA/RNA-binding protein ILF3. Identified through genome-wide screens in human pluripotent stem cells (PSCs), ILF3 is required for proper exit from pluripotency and lineage specification in human and primate—but not mouse—PSCs. Our data show that ILF3 interacts with and inhibits the RNA editing enzyme ADAR1 to limit adenosine-to-inosine (A-to-I) editing at primate-specific Alu elements, thereby preserving accurate splicing of developmental transcripts. These findings implicate ILF3 as a critical regulator of transcriptome fidelity in early primate development and introduce a novel paradigm where species-specific RNA processing fidelity serves as a developmental checkpoint. To define the developmental and mechanistic roles of ILF3, we propose three integrated aims. In Aim 1, we will use cross-species gastruloid models from human, chimpanzee, rhesus monkey, and mouse to assess ILF3's role in early lineage transitions and test whether it defines a primate- specific pathway in mammalian development. In Aim 2, we will map nascent RNA editing following acute ILF3 depletion using SLAM-seq and identify the protein domains mediating ILF3-ADAR1 interaction, linking RNA editing regulation to cell fate control. In Aim 3, we will define how ILF3 impacts RNA processing at key developmental genes by integrating splicing analysis and quantitative proteomics, uncovering direct effectors of lineage specification. Moreover, we will establish a causal link between expression of mis-edited and mis-spliced developmental regulators and proper gastruloid formation through rescue experiments. This research will uncover a previously unrecognized RNA-based regulatory mechanism controlling early primate development and provide insight into how defects in RNA editing and splicing may contribute to congenital disease. By establishing a functional framework for ILF3 in safeguarding human cell fate transitions, this work will inform future strategies for therapeutic intervention in developmental disorders, directly supporting NICHD's mission to understand and treat the origins of birth defects.

NIH Research Projects · FY 2026 · 2026-05

Gestational diabetes mellitus (GDM), defined as glucose intolerance first diagnosed during pregnancy, affects up to 18% of pregnancies in the U.S. and significantly increases risk for both mothers and offspring, including pre-eclampsia and long-term development of type 2 diabetes and metabolic syndromes. Despite its prevalence, GDM lacks treatments targeting its underlying mechanisms. Current therapies focus solely on glucose control while ignoring adipose tissue dysfunction, highlighting the urgent need for novel therapeutic targets addressing both hyperglycemia and adipose dysfunction. Recent studies suggest that adrenomedullin (ADM), a multifunctional peptide, plays a causal role in the development of GDM by suppressing insulin secretion in human β-cells and promoting lipolysis in adipose tissue. Importantly, we and others have found elevated ADM levels in the maternal serum and amniotic fluid of women with GDM, supporting a pathophysiological role during pregnancy. Our preliminary studies demonstrate that ADM infusion in pregnant mice induces GDM-like features, including glucose intolerance, reduced β-cell function, and increased lipolysis. Most significantly, administration of an ADM antagonist, ADM22-52, reverses these abnormalities in our novel GDM mouse model, providing the first evidence for ADM antagonism as a promising therapeutic approach. We hypothesize that increased ADM levels and signaling during pregnancy play a causal role in the manifestation of GDM symptoms through mechanisms involving both β-cell dysfunction and adipose tissue dysregulation. We propose three complementary aims using innovative genetic models and pharmacological approaches. Aim 1 will investigate the role of ADM signaling in β-cell adaptations to pregnancy using newly developed inducible β-cell-specific receptor knockout mice in established GDM models and assessing effects on glucose tolerance, β-cell function and expansion, and underlying signaling pathways. Aim 2 will determine whether elevated placental ADM contributes to GDM pathophysiology using placenta-specific ADM knockdown via targeted lentiviral delivery and assessing the impact on maternal glucose homeostasis, lipid metabolism, and fetal outcomes. Aim 3 will determine if ADM antagonist treatment attenuates GDM symptoms using both prevention and reversal protocols to evaluate therapeutic potential. Building on our published GDM mouse models and preliminary ADM studies, our multidisciplinary team has proven expertise and institutional resources to execute this comprehensive investigation. This work will establish ADM as the first identified molecular target for treating hyperglycemia and adipose dysfunction in GDM, potentially transforming clinical management of this prevalent pregnancy complication. Our findings will provide the mechanistic foundation for developing the first targeted therapy for GDM that addresses its underlying pathophysiology rather than just managing symptoms. The research also has broader implications for understanding metabolic adaptations during pregnancy and may inform treatments for type 2 diabetes, which affects over 37 million Americans.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY Congenital hydrocephalus (CH) involves ventricular enlargement and has historically been attributed to impaired cerebrospinal fluid (CSF) flow. Recent evidence, however, reveals that neurodevelopmental defects underlie many CH cases. Indeed, genetic studies frequently implicate neural differentiation and timing factors rather than direct regulators of CSF homeostasis. Our work focuses on the MIR302 family of microRNAs, which orchestrate developmental timing by controlling both post-transcriptional and epigenetic programs. We previously found that complete loss of mir-302 causes severe neural tube defects. More recently, we developed a hypomorphic mir- 302 mouse model that displays classic CH features—dome-shaped skulls, ventriculomegaly, and aqueduct stenosis—and exhibits altered chromatin accessibility in neural stem cells. Preliminary single-nuclei RNA- sequencing indicates a defect in neurogenesis across forebrain and midbrain populations, highlighting a broader timing dysregulation. We hypothesize that miR-302 enforces heterochronic control of neuroepithelial stem cells, preventing precocious differentiation and safeguarding specialized structures like the subcommissural organ (SCO). In Aim 1, we will define how miR-302 functions as a post-transcriptional regulator by mapping direct miRNA:mRNA interactions (via AGO2-chimeric eCLIP) and measuring translational changes (via Ribo-seq), thus linking aberrant gene expression to the loss of miR-302. In Aim 2, we will examine how distinct MIR302 members modulate chromatin accessibility, particularly in dorsal midbrain cells forming the SCO, using single-nuclei RNA+ATAC multiome and Polycomb (PRC2) occupancy assays. By pinpointing the epigenetic mechanisms that fail in CH mutants, we will reveal why the SCO is especially susceptible to timing defects. Together, these studies will yield new insights into how miRNA-driven heterochronic regulation ensures proper neuronal lineage commitment and SCO maintenance—key processes disrupted in CH. Our findings may inform novel therapeutic strategies aimed at restoring developmental timing in congenital brain malformations.

NIH Research Projects · FY 2026 · 2026-05

Project Summary/Abstract. Despite the marked genomic heterogeneity of bladder cancer (BLCA), current clinical practice treats it largely as a uniform disease, resulting in suboptimal outcomes for a substantial subset of patients who do not respond to standard therapies. Thus, there is a critical need to define molecular subtypes and identify unique genomic and metabolic alterations in BLCA that can guide the development of precision medicine approaches. To address this unmet need, we conducted an integrative analysis of transcriptomic, proteomic, and metabolomic datasets derived from BLCA patient tumors. This comprehensive approach identified xenobiotic metabolism, apical junction remodeling, and immune regulatory pathways as key contributors to BLCA progression. Our first-in-field findings demonstrate that >50% of TCGA-BLCA tumors harbor shallow or deep deletions of the gene encoding epoxide hydrolase 2 (EPHX2), a critical enzyme involved in the detoxification of endogenous epoxides. Importantly, low EPHX2 expression was associated with poor clinical outcomes, suggesting a tumor-suppressive role for EPHX2. Metabolomic profiling revealed that EPHX2 deficiency (heterozygous/deep deletions or low mRNA) leads to accumulation of epoxyeicosatrienoic acids (EETs), which are lipid signaling molecules and direct substrates of EPHX2. EETs have been shown to promote proliferation, metastasis, and immune evasion in several cancers, and our results suggest that their accumulation due to EPHX2 deficiency may have biological significance in BLCA. Our preliminary data demonstrate that EPHX2 suppressed tumor progression in vivo, while its loss activated the AKT-PKN3 axis, which is linked to aggressive phenotypes. NECTIN4, a tumor-associated antigen and therapeutic target, was also upregulated in EPHX2-deficient tumors. Pharmacological inhibition of PKN3 or targeting of NECTIN4 with enfortumab vedotin (EV) suppressed tumor growth. Interestingly, EPHX2- deficient tumors showed an “immunologically hot” profile with enhanced interferon signaling, suggesting potential for immunotherapy responsiveness. In the current proposal, we seek to further mechanistically define the role of EPHX2 loss in BLCA progression and determine whether EPHX2 loss–specific signaling pathways can be therapeutically targeted to treat BLCA. In Aim 1, we will determine the mechanisms by which EPHX2 deficiency promotes tumor progression in BLCA. In Aim 2, we will determine the mechanisms by which EPHX2 deficiency induces NECTIN4 expression and impacts the TIME. In Aim 3, we will define the impact of combination treatment with EV, anti-PD1, and PKN3 inhibitor on the TIME and anti-tumor responses in EPHX2-deficient BLCA. At the basic science level, this project seeks to define how EPHX2 deficiency drives BLCA progression through metabolic and immune remodeling, using single-cell RNA sequencing, metabolomics, ATAC-seq, and single-cell spatial transcriptomics (including Xenium 5K, COMET) to profile human tumors and relevant mouse models. Single-cell RNA sequencing will reveal cellular heterogeneity and immune signaling in EPHX2-deficient tumors, while spatial multi-omics will map tumor-immune architecture and cell interactions in situ. Translationally, these insights will support the development of a triple combination therapy with PKN3 inhibitors, NECTIN4-directed agents (e.g., EV), and immune checkpoint therapy (e.g., anti–PD-1) for EPHX2-deficient BLCA. This approach has the potential to improve upon current frontline treatments for advanced urothelial BLCA by enabling biomarker-driven combination strategies.

NIH Research Projects · FY 2026 · 2026-05

Project Summary/Abstract: Despite the CDC’s increased awareness of tick-borne disease in the United States, the current framework does not fully address the public health significance of argasid (Ornithodoros) ticks and relapsing fever (RF) Borrelia. However, RF Borrelia cause severe disease including recurring febrile episodes, nausea, vomiting, and miscarriage, and are often misdiagnosed due to limited awareness. Unlike ixodid ticks, Ornithodoros species exhibit a complex life-cycle and reproductive biology, including autogeny (egg-laying without a blood meal) and multiple gonotrophic cycles. These traits enable the rapid establishment of endemic pathogen foci. However, major knowledge gaps include a poor understanding of infection prevalence in ticks, transovarial transmission (ToT) dynamics, and the molecular mechanisms driving ToT. Our long-term goal is to elucidate the biological and genetic mechanisms that facilitate the maintenance of pathogens in Acari. The rationale and significance of this application is that by understanding the transmission cycle of Borrelia turicatae in field collected tick populations, we can predict disease emergence, persistence, and identify targets to neutralize Acari-borne pathogens. Toward this, we implemented extensive fieldwork across the U.S. and Mexico and assembled the most diverse collection of naturally infected Ornithodoros turicata from densely populated environments. Our findings revealed a broader geography for O. turicata than previously considered, and that these ticks can vertically transmit B. turicatae by autogenous reproduction. Interestingly, we also identified a unique B. turicatae isolate that transmits via tick bite but lacks vertical transmission capability, providing a unique opportunity to delineate the genetic basis of ToT. Our central hypothesis is that specific B. turicatae genotypes are associated with a ToT phenotype in naturally infected O. turicata ticks. To test this hypothesis, we propose two specific aims. Aim 1 will investigate ToT and filial infection rates in O. turicata naturally infected with B. turicatae. Using molecular detection and animal models, we will isolate novel strains and quantify ToT across reproductive cycles. This will clarify how B. turicatae is maintained in nature and inform public health strategies for managing this pathogen. Aim 2 will identify B. turicatae genotypes associated with ToT through comparative genomics and transcriptomics. Leveraging our in- house genomic infrastructure, we will analyze chromosomal and plasmid content to pinpoint genetic elements linked to ToT. Transcriptomic profiling will further refine candidate genes by identifying those up-regulated in the tick versus mammalian hosts. Innovation of this study lies in the integration of field ecology, pathogen isolation, and advanced genomics to identify genetic candidates associated with a ToT phenotype. With our newly reported O. turicata genome and B. turicatae isolates that will be generated in this application, we envision using this model to define the molecular mechanisms driving ToT of Acari-borne pathogens.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY The sigmoidal shaped Gompertz curve has been long accepted to fit lifespan survival curves from the single-celled budding yeast to invertebrate worms and flies, and to all mammalian species. It is not surprising to see the broad variation in lifespan among humans and most animal models due to genetic diversity and variability in the environment. However, it is striking that similarly broad variations in lifespan are commonly observed in well-controlled experimental environment and in laboratory species where genetically homogeneous individuals, such as inbred lines, self-fertilized animals, or mitotically reproduced yeast cells, are analyzed. What causes the lifespan variation? We hypothesize that the cause of such lifespan variation lies in epigenetic variation/drifts, either stochastic or non-stochastic, or both. Intriguingly, recent studies suggest that multiple aging trajectories exist and are modifiable during yeast replicative aging, offering new clues for the molecular basis for lifespan variation. In this exploratory project, we will attempt to identify and define the factors and pathways that contribute to the observed lifespan variation beyond invariable genetic and environmental factors through unbiased single- cell transcriptomic and epigenomic analysis. First, single-cell transcriptomes/epigenomes for complete daughter cell series of individual mother cells will provide, for the first time, a sneak peak of the mother cell’s aging status, providing clues for lifespan predictors and potential sources of lifespan variation. Next, the mother-daughter series will provide a first glimpse of unbiased aging trajectories. Finally, 10X genomics-based high throughput single-cell RNA-seq and ATAC-seq for young and old cell populations will enable a complete and unbiased analysis of aging trajectories and identification of molecular pathways responsible for lifespan variation. Understanding the root cause of lifespan variation beyond genetic variation has the tremendous potential to benefit the vast majority of the population in achieving healthy and successful longevity without genetic interventions. Such non-genetic interventions are likely to be more easily deliverable and achievable.

NIH Research Projects · FY 2026 · 2026-05

Project Summary Bladder cancer (BLCA), the sixth most common cancer in the United States and 9th overall among all cancers, is rarely diagnosed in individuals aged <40 years. The Cancer Genome Atlas (TCGA) described the genomic landscape of BLCA patients and noted that >60% of cases have alterations in subunits of SWItch/sucrose non- fermentable (SWI/SNF) nucleosome remodeling complexes, such as SMARCB1, also known as integrase interactor 1 (INI-1). Presently, the response rate of BLCA to standard-of-care therapies is relatively low, and therefore, the identification of novel metabolic pathway-mediated druggable targets is urgently needed. Our preliminary data demonstrate that SMARCB1 loss expression has a significantly worse prognosis in patients with BLCA. Orthotopically implanted SMARCB1-knockout (KO) xenograft shows enhanced tumor growth and metastasis. While attempting to identify the metabolic landscape mediated by SMARCB1 loss BLCA, we have identified altered methionine metabolism, nucleotide synthesis, and glutathione metabolism. Our current proposal will seek to define further the metabolic pathway by SMARCB1 loss in BLCA progression as well as immunometabolism and determine whether the key pathways can be therapeutically targeted for the treatment of BLCA. In aim 1, Determine the metabolic alteration by SMARCB1-loss BLCA tumor cells and tumor infiltrating immune cells. In aim 2, Trace the key metabolic pathways in SMARCB1 loss metastatic BLCA. At the level of basic biology, this project aims to understand the metabolic rewiring mediated by SMARCB1 loss in BLCA progression as well as immunometabolism and metastasis by utilizing cutting-edge high-resolution mass spectrometry techniques to profile the metastatic mediated tumors cells and immunometabolism harboring SMARCB1 loss. This will further examine the pathway-specific metabolic regulation non-invasive liquid diet delivery of stable isotopes into mouse models, which will lay the foundation to test the therapeutic strategy in the future.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY Sickle cell disease (SCD) is a devastating inherited hemolytic anemia that affects millions of people worldwide. Over 500,000 infants are born with SCD annually and the majority die before 5 years of age due to spleen dysfunction. In studies conducted with my K23 award, we determined that spleen damage in SCD impacts adaptive immunity. We identified an age-related decline in unswitched memory B cells (UMBC), the peripheral blood equivalent to splenic marginal zone B cells, and a corresponding increase in naïve B cells compared to children without SCD. Children with SCD/very low UMBC had >2-fold lower splenic expression of three genes important for B cell differentiation compared to SCD/low UMBC: IL21R, PF4, and CX3CR1. Expression of genes for ligands that activate B cell differentiation, DLL1 and JAG1, were significantly higher in children with SCD/very low UMBC compared to SCD/low UMBC. These data suggest that IL21R, PF4, CX3CR1, DLL1, and JAG1 have a role in the mechanism of MZB loss, B cell differentiation, and adaptive immunity in SCD. There is a critical gap in knowledge about the mechanisms of adaptive immune dysfunction in the spleen, and how to target these pathways to prevent life-threatening infections and autoimmunity in SCD. Our purpose of this limited R03 award is to prioritize genes important for B cell development in SCD spleen for future clinical and mechanistic studies. Our central hypothesis is that SCD alters expression of key genes important for B cell differentiation, leading to low UMBCs and higher naïve B cell counts. Aim 1. Develop an ex vivo system to investigate the role of IL21R, PF4, and CX3CR1 in B cell development in SCD. We will validate our findings with RNA sequencing of additional spleen samples. We will measure serum IL21, PF4, and fractalkine (the ligand for CX3CR1) by ELISA in SCD and correlate levels with B cell subsets. We will differentiate CD34+ stem cells into B cells to compare expression and activity of IL21R, PF4, and CX3CR1 in SCD- versus non-SCD-derived B cell subsets using flow cytometry and transcriptomic approaches. Aim 2. Determine the role of DLL1 and JAG1 in B cell differentiation in the spleen in SCD. We will use spatial transcriptomics to localize DLL1 and JAG1 signaling in human spleen tissue. We will use imaging flow cytometry to compare interactions between cells that express DLL1 and JAG1 and B cells in spleen tissue from patients with and without UMBC loss. We will validate the Townes SCD mouse model as a tool to examine how inflammatory stimuli influence the expression of Dll1 and Jag1 in the spleen in vivo. Impact: I expect my research will lead to significantly improved outcomes for SCD by identifying novel pathways in adaptive immunity that contribute to complications in SCD. Enhanced understanding of these pathways will yield new targets urgently needed for druggable disease modification. Within two years, I will have necessary tools and preliminary data to apply for independent funding through an R01 or similar mechanism.

NIH Research Projects · FY 2026 · 2026-05

PROJECT SUMMARY This application requests funds to purchase a cellenONE X1 Neo single-cell isolation and liquid dispenser system from Cellenion. The proposed instrument will be located in the Mass Spectrometry Proteomics Core at Baylor College of Medicine. The cellenONE X1 Neo is essential for establishing ultra-low-input proteomics capabilities at BCM and will be primarily used to isolate single cells and subcellular structures from clinical samples, pre-clinical patient-derived xenograft models, and various animal- and cell-based model specimens. Configured with protein sample processing workflows for bottom-up mass spectrometry, this platform will meet critical sample preparation needs for picogram- and nanogram-level starting materials, which demand extremely precise, low-volume, and contamination-free sample handling not adequately supported by our standard core protocols. Single-cell and spatial proteomics is a novel and rapidly advancing area of biomedical research with the potential to transform our understanding of cellular heterogeneity and disease mechanisms. However, despite BCM’s extensive research infrastructure, this capability is currently lacking at our institution. The addition of the cellenONE X1 Neo represents a significant leap forward, enabling our core to offer a complete, automated solution for ultra-sensitive proteomic analysis. Importantly, this instrument will leverage a recent acquisition of the Bruker timsTOF Ultra2 in the Mass Spectrometry Core – a $1.2 million investment in state-of-the-art mass spectrometry instrumentation capable of measuring ultra-small-scale proteomes. Although this Bruker timsTOF is already used for other challenging applications, the absence of a suitable single-cell preparation platform remains a critical barrier to adopting true single-cell and spatial proteomics workflows. The unifying aim of the projects supported by the cellenONE X1 Neo is to explore the molecular mechanisms driving normal physiology and disease at the level of individual cells or rare cell populations. This instrument will provide the precision, scalability, and operational robustness necessary to meet the evolving needs of our growing user base. Its integration into the Mass Spectrometry Proteomics Core aligns with BCM’s strategic plan to expand and share cutting-edge proteomics capabilities and will directly enhance research initiatives in cancer, metabolic disease, neuroscience, immunology, and beyond. The cellenONE X1 Neo will position the Core, and BCM more broadly, as a regional leader in ultra-sensitive proteomics by providing a comprehensive, accessible sample processing solution.

NIH Research Projects · FY 2026 · 2026-04

Project Summary: Mutations in genes encoding excitation-contraction coupling (ECC) proteins underlie a variety of congenital myopathies. Most ECC-associated congenital myopathies display sarcoplasmic reticulum (SR) Ca2+ leak and abnormal t-tubule/triad structures. Elevated SR Ca2+ leak via the skeletal muscle Ca2+ release channel, RYR1, contributes to the decline in muscle function in both myopathies, regulates basal muscle thermogenesis and metabolism, fatigue resistance, and the beneficial effects of exercise on mitochondrial respiratory capacity and/or biogenesis. We found that SPEG negatively regulates Ca2+ leak via phosphorylation of serine 2902 on the Ca2+ release channel, RYR1 and created a mouse model with S2902 converted to an aspartic acid (D) to mimic phosphorylation. The S2902D mutation decreased SR Ca2+ leak in muscle fibers from SPEG-deficient mice and mice with a dominant Y524S mutation in RYR1 (YS) associated with temperature- dependent increases in SR Ca2+ leak, Malignant Hyperthermia Susceptibility (MHS), and enhanced sensitivity to heat stroke (ESHS). Our working hypotheses to be tested in this application are: 1) SPEG kinase phosphorylates RYR1 at S2902 via its second kinase domain (KD2) to regulate SR Ca2+ leak. 2) The S2902D mutation slows the decline in muscle/mitochondrial function with aging. 3) The S2902D mutation improves muscle function in myopathies that display elevated SR Ca2+ leak. 4) Sustained decreases in SR Ca2+ leak suppress exercise driven mitochondrial function/biogenesis. 5) S107 improves muscle function in myopathies initiated by SR Ca2+ leak but not those that arise from triad disruption. 6) S107 may have off target effects that will be identified using the S2902D mice. To test these hypotheses, we will:SA1. Elucidate the role of SR Ca2+ leak in muscle function. SA2. Identify functional roles and targets of the SPEG kinase domains in skeletal muscle. SA3. Determine if S107 has off target effects and assess its efficacy for improving muscle function in WT, S2902D, YS and Speg deficient mice. This study will define interactions among triadic proteins, define the role SR Ca2+ leak, and the two kinase domains on SPEG in muscle function, assess side effects of S107 and lay the groundwork for development of therapeutic interventions for congenital myopathies arising from mutations in triadic proteins.

NIH Research Projects · FY 2026 · 2026-04

PROJECT SUMMARY CD8 T cells directly mediate the specific killing of virally infected and cancerous cells. Upon recognizing a specific antigen presented on a target cell, T cells become activated and acquire effector function, including the secretion of perforins and granzymes to cause target cell death. However, when the antigen is not readily cleared, as in chronic viral infections and cancer, T cells enter a state of exhaustion where they express co- inhibitory molecules like PD-1 and lose effector capacity. T cell exhaustion is a major contributor to the persistence of chronic viral infections and cancer. Inhibition of CD8 T cell co-inhibitory pathways is the basis of immune checkpoint blockade (ICB), which reinvigorates T cell anti-tumor responses and can dramatically improve cancer outcomes. However, patient responses are variable, which can partially be attributed to the heterogeneity of exhausted T cell populations. ICB acts directly on a subset of exhausted T cells called progenitor cells, which expand and differentiate into intermediate cells, which have increased effector function. However, intermediate cells are short-lived and become terminally exhausted cells with low effector function. Understanding the mechanisms of differentiation from progenitor to terminal exhausted states will vastly improve patient responses to immunotherapy. Our group recently found that mouse and human exhausted T cells express high levels of granzyme A (GzmA). Granzymes are a class of serine proteases that mediate target cell death, with granzymes A and B being the most abundant granzymes. While granzyme B (GzmB) is essential for T cell cytotoxicity and is reduced during exhaustion, little is known about the role of GzmA. Our preliminary findings suggest a conversion from GzmB in effector T cells to GzmA in exhausted T cells, but it remains unknown how this process impacts the differentiation and function of exhausted T cells. We hypothesize that GzmA expression is a compensatory mechanism in response to GzmB downregulation that functions to increase cytotoxic capacity during T cell exhaustion. We will mechanistically dissect the role of GzmA in CD8 T cell exhaustion by generating a murine Gzma-/- model and tracking T cell function during chronic viral infection and tumor progression. Aim 1 will use flow cytometry, single-cell RNA-sequencing, and functional assays to determine the CD8 T cell-intrinsic effects of GzmA deletion during the longitudinal progression of T cell exhaustion during chronic viral infection. Aim 2 will test how GzmA deletion impacts anti-tumor T cell function in the tumor microenvironment. Together, these aims will define the function of GzmA in exhausted T cells and elucidate novel mechanisms in CD8 T cell exhaustion. The collaborative training environment, the cutting-edge core facilities, and the many experts in T cell immunology at Baylor College of Medicine and the Texas Medical Center will strongly support the success of this project. The integrative training plan will comprehensively prepare the applicant for an academic physician- scientist career studying mechanisms of T cell biology to improve clinical outcomes for rheumatology patients.

NIH Research Projects · FY 2026 · 2026-04

PROJECT SUMMARY/ABSTRACT Acute myeloid leukemia (AML) has persistently maintained a low ~32% 5-year survival rate in spite of over three decades of medical research. With approximately 22,010 in the U.S being diagnosed with AML and 11,090 dying from the disease yearly, there remains an urgent need to develop new therapies and treatment strategies. Understanding the key protein drivers of AML and the regulatory mechanisms governing expression of these proteins has provided us with an opportunity to specifically target the disease. The most common variants of AML in both pediatric and adult patients depend upon the chromatin binding MLL protein complex. Recently developed small molecule menin-inhibitors have demonstrated remarkable clinical success by inhibiting MLL complex formation. However, close to 40% of patients treated with menin inhibitors for prolonged periods develop resistance and subsequently relapse, demonstrating an urgent need for combination therapy. Our lab has previously shown that a critical component of the MLL complex, LEDGF, is sensitive to perturbations in translation due to its short half-life. I demonstrated that LEDGF protein expression can be inhibited with the RNA helicase eIF4A1 inhibitor silvestrol, and that silvestrol has potent anti -AML properties. The following aims will test the hypothesis that eIF4A1 inhibition is an effective AML therapy in vivo, capable of circumventing menin inhibitor resistance. In Aim 1 I will generate novel mouse models of menin inhibitor resistant adult and pediatric AML to test the efficacy of eIF4A1 inhibition as an AML therapy. In Aim 2 I will identify the molecular mechanisms by which eIF4A1 contributes to LEDGF translation, exploring the role of eIF4A1 in maintaining AML cells. The long-term objectives of this project are to characterize a clinically relevant new approach to treat AML and uncover molecular mechanisms governing mRNA translation. This fellowship application is sponsored by Dr. Daisuke Nakada, PhD, an expert in hematopoietic stem cell biology and acute myeloid leukemia biology. This training plan is designed to 1) provide mentorship from experts in science and medicine; 2) develop general and field-specific scientific knowledge in stem cell, chromatin, and RNA biology; 3) grow my scientific communication skills and form professional networks; and 4) develop clinical skills and knowledge toward a pediatrician-scientist career. The clinical and scientific training environment is at Baylor College of Medicine, located in the heart of the Texas Medical Center with close ties to institutions such as Texas Children's Hospital and MD Anderson Cancer Center. This environment is ideal to foster scientific and clinical growth toward my long-term goal of becoming a physician scientist in the field of pediatric hematology-oncology.

NIH Research Projects · FY 2026 · 2026-04

PROJECT SUMMARY Gastrointestinal acute radiation syndrome (GI-ARS) is a consequence of exposure to high doses of ionizing radiation and is characterized by extensive damage to the intestinal epithelium that leads to loss of barrier function, sepsis, and in some cases mortality. Currently there is a critical need to develop new physiologically relevant human models to study GI-ARS and to evaluate potential medical countermeasures (MCMs). This project aims to establish human intestinal organoids (HIOs) as a robust in vitro model for GI-ARS using high- content imaging approaches to assess the therapeutic potential of a microbial based MCM. Optimization of radiation dosing will be performed using a large cohort of HIOs that allow assessment of sex, age, and intestinal region on the response to radiation to be interrogated. A library of biomarkers of radiation damage will be assembled using novel screening approaches that combine multi-omics analysis, bioinformatic pipelines, and network analysis. Following biomarker identification, Cell Painting, a high content morphological profiling technique, will be implemented to characterize the cellular response to radiation treatment in a high throughput manner using a scanning disc confocal microscope and customized analyses package. The generation of detailed cellular and subcellular phenotypic profiles that associate with radiation will be used to enable rapid, quantitative assessment of therapeutic efficacy of a microbial based MCM. The MCMs to be tested are Limosilactobacillus reuteri 6475 (LR6475) organisms as a modality to deliver key growth factors necessary to promote regeneration and repair of the intestinal epithelium that target the intestinal stem cell. At the completion of the proposed studies, HIO will be validated as a translatable model for GI-ARS and a novel imaging based phenotypic screening pipeline for radiation injury and MCM evaluation will be established. This work will significantly advance efforts in radiation countermeasure development, facilitate future therapeutic screening and support preparedness for radiological emergencies.

NIH Research Projects · FY 2026 · 2026-04

PROJECT SUMMARY. Proper CNS function requires intricate axon-glia interactions. In the optic nerve, for example, each myelinating oligodendrocyte (OL) physically contacts up to 60 axons, forming the largest intercellular junction in vertebrates - the paranodal junction (PNJ). The PNJ anchors the myelin sheath to the axon, is the main mechanism responsible for ion channel clustering at the nodes of Ranvier and serves as a central point of communication between the axon and OLs. Recently, more and more evidence on disrupted nodes and paranodes have been reported in neurological and psychiatric disorders, axonal injury and regeneration, and aging. However, our knowledge of this unique axon-glia interaction is still very limited, especially about its molecular composition. This reflects the significant technical challenges associated with the lipid-rich and insoluble nature of the PNJ, as well as the lack tools to reliably visualize, disrupt, and evaluate the axon-glia interactions in vivo. Lastly, validating new paranodal proteins requires reliable antibodies, the lack of which has hindered progression of scientific discoveries and caused major concerns in reproducibility. To overcome these challenges, I have designed a reliable and medium-throughput pipeline for novel protein discovery at axoglial junctions with rapid validation and downstream functional analyses in vivo. I propose to combine proximity-biotinylation based subdomain proteomic profiling, CRISPR/Cas9-based genome editing, and a highly efficient and cell type-specific AAV-delivery system. My early postdoctoral work has established the importance of the paranodal scaffolding protein AnkyrinG (AnkG), which will be used as a molecular entry point to further dissect the PNJ. In Aim1, I propose to use proximity proteomic approach to bypass the difficulty in efficient protein isolation and identification at the PNJ. Our lab has developed a unique conditional knock-in mouse model with TurboID fused to the C-terminus of the endogenous AnkG protein, where proteins enriched at the PNJ can be covalently labeled with biotin, efficiently purified and identified by mass spectrometry. I will functionally validate the candidate proteins using an optimized CRISPR-Cas9 based AAV-mediated genome- editing system to efficiently target oligodendrocytes in vivo. This allows for direct visualization of the endogenous protein in addition to gain- and loss-of-function experiments in vivo. In Aim2, I will begin with the functional analysis of a novel candidate at the PNJ, Palm2. In Aim3, I will examine the contribution of the novel candidates identified at PNJ to axonal injury repair using an optic nerve crush model. Successful completion of this project will reveal the functions of novel oligodendroglial PNJ proteins, thereby bridging a critical knowledge gap in axon-glia interactions and myelination. Moreover, our optimized pipeline for in vivo screening has the potential to transform future studies with genetic manipulation of OLs. It eliminates concerns associated with unvalidated antibodies and provides a rapid and reliable method for screening oligodendroglial protein localization and function.

NIH Research Projects · FY 2026 · 2026-04

PROJECT ABSTRACT Epilepsy is a debilitating and life-threatening condition, affecting 1% of the US population. A significant portion of these patients have seizures that do not respond to medication therapy. Neurostimulation is often an effective treatment method for these patients, but only in an adjuvant capacity. The seizure reduction experienced by patients is far from curative, and stimulation treatments rarely result in seizure freedom. By contrast, resective surgery, the gold standard in care for drug-resistant epilepsy, reliably results in sustained seizure freedom and an improved quality of life. However, it is important to note that surgery, despite its potential benefits, is a highly invasive procedure that carries certain risks and adverse effects. Moreover, its major limitation is that its use is restricted to brain regions that can be removed without causing a loss of essential neurological function. We believe that the limited effectiveness of current neurostimulation devices can be attributed to the crudeness of stimulation they provide. The brain, being a complex and non-linear system, requires a modulatory approach that matches its intricate nature when targeting networks involved in epilepsy. Achieving optimal control over these networks is likely to necessitate a complex approach. Therefore, we hypothesize that the generation of more complex patterns will allow for better engagement and modulation of these networks. Here we present a novel platform that offers an unprecedented ability to optimize the design of pulse sequences with complex spatiotemporal relationships for the control of epileptic activity. By combining a cutting-edge method for designing high-entropy stimuli and deep learning, we will demonstrate the ability to infer optimized stimulation for seizure control in a rat model. Our paradigm is based on adapting our Inception Loops paradigm, a deep learning framework for solving high-dimensional, non-linear optimization problems in neuroscience, for the pur- pose of constructing multi-patterned stimuli that are optimized to control epileptic activity. The first step involves building data-driven neural predictive models of targeted brain areas, taking ongoing brain activity and stochastic, high-entropy electrical stimulation patterns as input to predict neural activity. Then, in silico optimization identifies those dynamic stimulation patterns across many stimulation channels that suppress epileptic activity, which are then verified in vivo. The study detailed below will investigate the optimization of multi-pattern stimuli in two complementary rodent models. Finally, we will perform a first-in-human study to investigate the ability of multi-pattern stimulation to con- trol interictal epileptiform discharges as a seizure likelihood proxy in patients undergoing intracranial evaluation.

NIH Research Projects · FY 2026 · 2026-04

Project Summary Relapsing fever (RF) Borrelia are vector-borne pathogens that cause severe clinical manifestations. While RF Borrelia can be transmitted by lice and hard ticks, soft ticks transmit most RF Borrelia species. The unique biology of soft ticks causes concerns for future RF outbreaks. While soft ticks have three developmental stages, which is similar to hard ticks, they also have 2-7 instar nymphal stages and can feed multiple times as adults resulting in a 10–20-year life span. RF Borrelia are maintained in the tick through the molt to each new life stage and can be transovarially transmitted from mother to offspring creating >10 opportunities for a single tick to transmit a RF Borrelia infection. In humans, RF Borrelia repeatedly reach high densities in the blood (spirochetemia) and cause recurring febrile illness, neurologic complications, and perinatal death. Upon initiation of antibiotic treatment, 30-50% of patients experience an acute exacerbation of symptoms known as Jarisch- Herxheimer reaction (JHR). Unfortunately, due to the lack of a cost-effective animal model that mimics human RF disease, we do not understand the mechanisms leading the severe clinical manifestations caused by RF Borrelia. Mice are the most commonly used animals to study RF Borrelia infection and pathogenesis, but mice are a limited disease model because they do not become hyperthermic during RF Borrelia infection. Nonhuman primates develop fever during periods of spirochetemia, but are too expensive to routinely use for rigorous studies. In this R03 application, we propose to develop the Guinea pig model to study RF disease. A historical study described Guinea pigs as viable hosts for Borrelia hermsii and Borrelia turicatae, the two Borrelia species that cause the most RF disease in North America. Both B. hermsii and B. turicatae repeatedly reached high densities in Guinea pig blood, and Guinea pigs become hyperthermic during spirochetemic episodes. Due to a lack of follow-up studies, the RF Borrelia-Guinea pig model remains largely uncharacterized in terms of pathogenesis, disease pathology, and JHR development. We hypothesize Guinea pigs will model human RF disease by inducing hyperthermia during spirochetemic episodes, producing pro-inflammatory cytokines during infection, and developing signs of JHR following antibiotic administration. To test this, we will assess B. hermsii and B. turicatae pathogenesis in Guinea pigs through quantification of spirochetemia, asses clinical signs of RF disease by measuring weight loss and body temperature of Guinea pigs and quantify cytokine production and tissue damage caused by B. hermsii and B. turicatae infection (Aim 1). We will also evaluate the development of JHR in Guinea pigs by measuring body temperature and quantifying cytokine levels after antibiotic treatment (Aim 2). Our thorough characterization of the RF Borrelia-Guinea pig model is critical to finding a relevant animal model to perform mechanistic and intervention studies to help mitigate the severe clinical manifestations cause by RF Borrelia.

NIH Research Projects · FY 2026 · 2026-04

PROJECT SUMMARY Our long-term goal is to understand how rotaviruses (RVs) cause life-threatening diarrhea and to develop vaccines to combat this pathogen. Despite the global introduction of vaccines for RV over a decade ago, RV infections still cause >200,000 deaths annually, mostly in low-income countries, creating an urgent need for better vaccines to overcome this mortality. The structure of this large icosahedral virus is complex, consisting of three concentric capsid layers (triple-layered particles, TLPs) that encapsidate 11 genomic dsRNA segments. TLP assembly is unique and requires the viral nonstructural protein 4 (NSP4). NSP4, initially synthesized as an endoplasmic reticulum transmembrane 175 amino acid glycoprotein, serves as an intracellular receptor for nascent immature double layered particles (DLPs). DLPs bind to the cytoplasmic C-terminus of NSP4 and bud through NSP4-containing membranes and acquire a transient membrane. Through a poorly understood mechanism, the transient membrane is lost and the outer capsid proteins, the glycoprotein VP7 and the spike protein VP4, are assembled forming the infectious TLP. We previously characterized a domain of NSP4 that interacts with the stalk domain of VP4, which may be instrumental in outer capsid protein assembly onto TLPs. Unexpectedly, more recently, we discovered a domain of NSP4 is part of infectious animal and human RV TLPs but not DLPs. Immuno-electron microscopy clearly shows NSP4 associates with TLPs as detected by rabbit polyclonal anti-NSP4 antibody. Rabbits parenterally immunized with CsCl and sucrose gradient purified, psoralen-inactivated RV TLPs develop antibodies against NSP4 but not against any other known RV nonstructural proteins. Importantly, we previously demonstrated NSP4 interacts with integrins that have been implicated as RV receptors. Integrins are primarily located on the basolateral surface of intestinal epithelial cells where human RVs infect. Preliminary data shows NSP4 antibodies neutralize RV infectivity. Together, these data indicate a domain of NSP4 is a previously unrecognized component of virus particles. Our central hypotheses are a domain of NSP4 is retained on TLPs, NSP4 mediates the basolateral infection of human epithelial cells and NSP4 antibodies will neutralize RV infectivity. We propose experiments to answer: (1) Which domain of NSP4 is retained on RV, and where is NSP4 located on the TLP? (2) Do NSP4 antibodies neutralize human RV basolateral infection of human intestinal enteroids? While a correlate of protection against RV has not been determined, NSP4 antibodies ameliorate NSP4 induced diarrhea, and studies indicate NSP4 antibodies acquired by natural RV infection are associated with reduced RV diarrhea and seizures. NSP4 may become a new component of non-replicating injectable vaccines, either inactivated RV or subunit vaccines. Such vaccines that bypass the gut could be more effective than oral vaccines in low-income settings by avoiding factors that may limit immune responses in the intestine, such as gut inflammation, malnutrition, or co-infections.

NIH Research Projects · FY 2026 · 2026-04

Project Summary Leishmaniasis, caused by Leishmania spp., is a neglected tropical disease with a significant global health burden. It is estimated to affect over 6.2 million people globally, with over 1 million incident cases anually. While cutaneous leishmaniasis is considered endemic to tropical and subtropical regions of South America, Central America, and Mexico, Leishmania has also been quietly spreading northward and establishing itself in the United States. Autochthonous transmission of Leishmania occurs in several areas, including Texas, where diagnosed cases of cutaneous leishmaniasis are predominately acquired locally. Understanding the impact of leishmaniasis in the US is compounded by the challenge of early detection and diagnosis, as symptoms resemble those of other common skin conditions, so cases are often misdiagnosed or missed completely. Thus, passive surveillance is ineffective for detecting the true burden of disease, and even the mandatory reporting in Texas frequently misses cases. We critically need multi-level epidemiologic studies that include human, vector, and animal infection dynamics to fully understand the specific risk of Leishmania transmission. However, such studies do not currently exist. Therefore, we propose conducting a One Health investigation into the transmission of Leishmania in two major metropolitan areas in Texas: Houston and Dallas. We will first analyze hospital-based data of locally acquired leishmaniasis from major medical systems in Houston and Dallas, which will inform our sandfly surveillance investigations to elucidate this parasite’s burden and distribution in these areas. Additionally, we will test shelter dogs to identify enzootic transmission. Our preliminary data suggests that the prevalence of Leishmania in Texas vectors and animals is significantly higher than previously published. Our central hypothesis is that Leishmania is endemic in sandfly vectors throughout Texas, with a disproportionate burden in north- central Texas, and is causing disease in major metropolitan areas. Our aims are as follows: (1) Determine the prevalence of Leishmania in sandfly vectors through untargeted and targeted collections informed by locations of autochthonous human cases in Harris and Dallas County, Texas, and (2) Determine the prevalence of Leishmania-positive domestic dogs in Harris and Dallas County, Texas. The proposed research represents a foundational study to evaluate disease transmission and provide critical data for public health decision making. Our long-term goals are to define the geospatial epidemiology of leishmaniasis in the southern United States, and to design targeted public health interventions to prevent transmission. This study brings together a collaborative team to begin to tackle a growing public health problem with no active surveillance testing funded by other means. Our findings will critically impact our understanding of leishmaniasis as this disease continues to invade the US and will allow us to identify high-risk populations for targeted prevention and intervention efforts.

NIH Research Projects · FY 2026 · 2026-04

PROJECT SUMMARY Age-related macular degeneration (AMD) is the leading cause of vision loss in the elderly that results from deterioration of the photoreceptor support system, including retina and retinal pigment epithelium (RPE). Knowledge of genetic risk factors underlying AMD susceptibility has advanced rapidly during the past decade with the advent of Genome-wide Association Studies (GWAS), which have established a critical role of common variants in AMD. However, the absence of comprehensive functional testing for the majority of AMD-GWAS variants to identify causal variants and regulatory regions, along with the unexplored underlying mechanisms, presents a significant knowledge gap prohibiting the full realization of novel drug targets and/or personalized treatments. This proposal addresses these gaps by applying innovative high-throughput functional genomics approaches to test the hypothesis that non-coding risk variants exert their effects through gene expression regulation that are enriched within specific functional networks in the disease-relevant tissues. Our hypothesis is supported by two key preliminary data. First, we built the largest and first reference eQTL map of 406 post-mortem human donor retina and integrated this with AMD-GWAS data to identify target genes at six AMD loci. Studies in RPE also supported the findings that AMD-associated variants exert their effects through gene expression regulation. Additionally, open chromatin profiles of retina and RPE are significantly enriched for AMD heritability with maximal enrichment in RPE. Secondly, genetic risk factors in AMD converge into key biological pathways including complement, inflammation and immune response, and our work has shown that they are closely connected in co-expression networks. Thus, we propose to utilize iPSC- derived RPE (iPSC-RPE) cell lines for understanding the molecular chain of causality by integrating genetic, transcriptomic and epigenetic data. In aim 1, we will characterize CREs in iPSC-RPEs using ATAC-seq, ChIP- seq, integrate them with published AMD-GWAS data, and perform high-throughput reporter assays to identify functional CREs and causal variants with significant differences in allelic activities. In aim 2, we will augment the novel AMD candidates through perturbations of known AMD genes and studying their effect on gene regulatory networks. The proposed research is significant as the integration of multiple 'omics' data will offer a mechanistic understanding of immune dysfunction in AMD. Additionally, harnessing the susceptibility regulatory networks and pathways and defining their role in AMD will improve the prioritization of potential therapeutic targets. Furthermore, this project will establish a suitable disease model for AMD. Currently, in vitro models lack key features of human RPE, and mouse models are inadequate because AMD-related vision loss involves degeneration of the macula, which is a primate-specific structure. Finally, as iPSC-derived autologous RPE patch transplantation emerges as a possible treatment for AMD, these studies provide key insights into the impact of genetic risk factors with significant implications for future therapy.