Selected Grantee Publications
Plural Molecular and Cellular Mechanisms of Pore Domain KCNQ2 Encephalopathy
Abreo et al., eLife. 2025.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11703504
This study investigates the cellular and molecular mechanisms underlying KCNQ2 encephalopathy, a severe type of early-onset epilepsy caused by mutations in the KCNQ2 gene. Researchers describe a case study of a child with a specific KCNQ2 gene mutation, G256W, and found that it disrupts normal brain activity, leading to seizures and developmental impairments. Male and female Kcnq2G256W/+ mice have reduced KCNQ2 protein levels, epilepsy, brain hyperactivity, and premature deaths. As seen in the patient study, ezogabine treatment rescued seizures in mice, suggesting a potential treatment avenue. These findings provide important insights into KCNQ2-related epilepsy and highlight possible therapeutic strategies. Supported by ORIP (U54OD020351, S10OD026804, U54OD030187), NCI, NHLBI, NICHD, NIGMS, NIMH, and NINDS.
Engineered Bacteria That Self-Assemble Bioglass Polysilicate Coatings Display Enhanced Light Focusing
Sidor et al., PNAS. 2024.
https://pubmed.ncbi.nlm.nih.gov/39656206
Organisms in nature have evolved to create multifunctional structures with advanced optical properties that can be used to design new optical materials. Researchers created constructs containing the enzyme silicatein, derived from sea sponges, and the outer membrane protein A (OmpA) to engineer Escherichia coli bacteria to express surface-level silicatein enzymes. Using Rhodamine123 staining and transmission electron microscopy, results showed that engineered E. coli expressing OmpA-silicatein displayed polysilicate encapsulation with smooth, nonruffled cell borders compared with wild-type E. coli. Light-scattering analysis demonstrated that engineered E. coli create photonic nanojets that are brighter than wild-type E. coli. This study serves as proof of concept that cells can be engineered for potential utilization as tunable photonic components. Supported by ORIP (S10OD030296) and NIGMS.
Immune Restoration by TIGIT Blockade is Insufficient to Control Chronic SIV Infection
Webb et al., Journal of Virology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38775481/
T-cell exhaustion from prolonged upregulation of immune checkpoint receptors (ICR) contributes to immune dysfunction and viral persistence of both human and simian immunodeficiency virus (HIV/SIV) infection. Previous in vitro research has demonstrated the potential use of ICR blockade as a therapeutic. Researchers used a monoclonal antibody targeting humanized T cell immunoreceptor with Ig and ITIM domain (TIGIT) in male and female cynomolgus macaque and female rhesus macaque SIV models, 4–14 years of age. TIGIT blockade was well tolerated, with moderately increased proliferation of T cells and natural killer cells, but a reduction in plasma viral load was not observed. Future research to eliminate SIV should combine ICR blockades with other immunotherapies. Supported by ORIP (P51OD011092), NIAID, and NIMH.
Elevated Inflammation Associated With Markers of Neutrophil Function and Gastrointestinal Disruption in Pilot Study of Plasmodium fragile Co-Infection of ART-Treated SIVmac239+ Rhesus Macaques
Nemphos et al., Viruses. 2024.
https://pubmed.ncbi.nlm.nih.gov/39066199/
Because of geographic overlap, a high potential exists for co-infection with HIV and malaria caused by Plasmodium fragile. Meta-analysis of data collected from 1991 to 2018 demonstrated co-incidence of these two infections to be 43%. Researchers used a male rhesus macaque (RM) model, 6–12 years of age, coinfected with P. fragile and antiretroviral (ART)-treated simian immunodeficiency virus (SIV) to mimic HIV/malaria co-infection observed in patients. ART-treated co-infected RMs demonstrated increased levels of inflammatory cytokines, shifts in neutrophil function, and gastrointestinal mucosal dysfunction. This model may be used to study molecular mechanisms of disease pathology and novel therapies, such as neutrophil-targeted interventions, for patients experiencing co-infection. Supported by ORIP (U42OD010568, U42OD024282, P51OD011104, R21OD031435) and NIGMS.
SREBP-Dependent Regulation of Lipid Homeostasis Is Required for Progression and Growth of Pancreatic Ductal Adenocarcinoma
Ishida et al., Cancer Research Communications. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11444119
Lipids are crucial for tumor cell proliferation, and sterol regulatory element-binding protein (SREBP) activation drives lipid synthesis and uptake to maintain cancer growth. This study investigated the role of the SREBP pathway and its regulator, SREBP cleavage–activating protein (SCAP), in lipid metabolism during the development and progression of pancreatic ductal adenocarcinoma (PDAC). Using female mouse xenograft models and male and female pancreas-specific Scap knockout transgenic mice, researchers demonstrated that SCAP is essential for PDAC progression in low-nutrient conditions, linking lipid metabolism to tumor growth. These findings highlight SREBP as a key therapeutic target for PDAC, offering potential strategies for improving treatment by disrupting cancer-associated metabolic reprogramming. Supported by ORIP (T32OD011089), NCI, NHLBI, and NIGMS.
Immune Gene Regulation Is Associated With Age and Environmental Adversity in a Nonhuman Primate
Watowich et al., Molecular Ecology. 2024.
https://pubmed.ncbi.nlm.nih.gov/39032090
The mammalian aging process involves a decline in physiological function, influenced by molecular mechanisms like epigenetic changes. These processes have been studied in controlled settings, however the role of aging in naturalistic populations remains unclear. This study explored the effects of environmental stressors (i.e., Hurricane Maria) on DNA methylation in free-living male and female rhesus macaques in Cayo Santiago, Puerto Rico. Results showed that environmental adversity accelerated age-related molecular changes, especially in gene transcription regions, while primary aging mainly affected nonregulatory regions. These findings highlight how the biology of aging is influenced by environmental factors. Supported by ORIP (P40OD012217), NIA, and NIMH.
SIV-Specific Antibodies Protect Against Inflammasome-Driven Encephalitis in Untreated Macaques
Castell et al., Cell Reports. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11552693
Viral infections are the most common infectious cause of encephalitis, and simian immunodeficiency virus (SIV)–infected macaques are a well-established model for HIV. Researchers investigated the protective effects of SIV-specific antibodies against inflammation-driven encephalitis in using untreated, SIV-infected, male and female pigtail and rhesus macaques. Findings indicate that these antibodies reduce neuroinflammation and encephalitis, highlighting the importance of antibodies in controlling neuroimmune responses, especially in the absence of antiretroviral therapy. This study provides insight into immune-modulatory approaches to combating inflammation-driven encephalopathies. Supported by ORIP (U42OD013117, T32OD011089), NIDA, NHLBI, NIAID, NINDS, and NIMH.
Mechanical Force of Uterine Occupation Enables Large Vesicle Extrusion From Proteostressed Maternal Neurons
Wang et al., eLife. 2024.
https://pubmed.ncbi.nlm.nih.gov/39255003
This study investigates how mechanical forces from uterine occupation influence large vesicle extrusion (exopher production) from proteostressed maternal neurons in Caenorhabditis elegans. Exophers, previously found to remove damaged cellular components, are poorly understood. Researchers demonstrate that mechanical stress significantly increases exopher release from touch receptor neurons (i.e., ALMR) during peak reproductive periods, coinciding with egg production. Genetic disruptions reducing reproductive activity suppress exopher extrusion, whereas interventions promoting egg retention enhance it. These findings reveal that reproductive and mechanical factors modulate neuronal stress responses, providing insight on how systemic physiological changes affect neuronal health and proteostasis, with broader implications for reproductive-neuronal interactions. Supported by ORIP (R24OD010943, P40OD010440), NIA, and NIGMS.
Gene Editing of Pigs to Control Influenza A Virus Infections
Kwon et al., Emerging Microbes & Infections. 2024.
https://pubmed.ncbi.nlm.nih.gov/39083026/
A reduction in the efficacy of vaccines and antiviral drugs for combating infectious diseases in agricultural animals has been observed. Generating genetically modified livestock species to minimize susceptibility to infectious diseases is of interest as an alternative approach. The researchers developed a homozygous transmembrane serine protease 2 (TMPRSS2) knockout (KO) porcine model to investigate resistance to two influenza A virus (IAV) subtypes, H1N1 and H3N2. TMPRSS2 KO pigs demonstrated diminished nasal cavity viral shedding, lower viral burden, and reduced microscopic lung pathology compared with wild-type (WT) pigs. In vitro culturing of primary bronchial epithelial cells (PBECs) demonstrated delayed viral replication in TMPRSS2 KO pigs compared with WT pigs. This study demonstrates the potential use of genetically modified pigs to mitigate IAV infections in pigs and limit transmission to humans. Supported by ORIP (U42OD011140), NHLBI, NIAID, and NIGMS.
Identifying Mitigating Strategies for Endothelial Cell Dysfunction and Hypertension in Response to VEGF Receptor Inhibitors
Camarda et al., Clinical Science. 2024.
https://pubmed.ncbi.nlm.nih.gov/39282930/
Vascular endothelial growth factor receptor inhibitor (VEGFRi) use can improve survival in patients with advanced solid tumors, but outcomes can worsen because of VEGFRi-induced hypertension, which can increase the risk of cardiovascular mortality. The underlying pathological mechanism is attributed to endothelial cell (EC) dysfunction. The researchers performed phosphoproteomic profiling on human ECs and identified α-adrenergic blockers, specifically doxazosin, as candidates to oppose the VEGFRi proteomic signature and inhibit EC dysfunction. In vitro testing of doxazosin with mouse, canine, and human aortic ECs demonstrated EC-protective effects. In a male C57BL/6J mouse model with VEGFRi-induced hypertension, it was demonstrated that doxazosin prevents EC dysfunction without decreasing blood pressure. In canine cancer patients, both doxazosin and lisinopril improve VEGFRi-induced hypertension. This study demonstrates the use of phosphoproteomic screening to identify EC-protective agents to mitigate cardio-oncology side effects. Supported by ORIP (K01OD028205), NCI, NHGRI, and NIGMS.