Selected Grantee Publications
Liver-Specific Transgenic Expression of Human NTCP In Rhesus Macaques Confers HBV Susceptibility on Primary Hepatocytes
Rust et al., PNAS. 2025.
https://pubmed.ncbi.nlm.nih.gov/39937851
This study establishes the first transgenic nonhuman primate model for hepatitis B virus (HBV). Male and female rhesus macaques were engineered to express the human HBV receptor, NTCP (hNTCP), specifically in the liver. Researchers used PiggyBac transposon technology to introduce a liver-specific NTCP transgene into embryos, which were then implanted into surrogate females. The resulting offspring expressed hNTCP in hepatocytes and demonstrated high susceptibility to HBV infection. This model overcomes the species-specific limitations of HBV research, providing a powerful tool for studying HBV biology and evaluating HBV treatments in a clinically relevant model system. Supported by ORIP (P51OD011092), NIDA, and NIAID.
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.
Impaired Axon Initial Segment Structure and Function in a Model of ARHGEF9 Developmental and Epileptic Encephalopathy
Wang et al., PNAS. 2024.
https://www.pnas.org/doi/10.1073/pnas.2400709121
Researchers developed a mouse model carrying the G55A missense variant identified in ARHGEF9 patients with severe epilepsy and neurodevelopmental phenotypes. Using male Arhgef9G55A mice, this study examined behavioral, molecular, and electrophysiological phenotypes in the Arhgef9G55A model of developmental and epileptic encephalopathies (DEE). Researchers found that the G55A variant causes disruption of inhibitory postsynaptic organization and axon initial segment (AIS) architecture, leading to impairment of both synaptic transmission and action potential generation. The effects of Arhgef9G55A on neuronal function affect both intrinsic and synaptic excitability and preferentially impair AIS. These findings indicate a novel pathological mechanism of DEE and represent a unique example of a neuropathological condition converging from AIS dysfunctions. Supported by ORIP (U54OD020351, U54OD030187, U54OD020351, S10OD026974) and NINDS.
Intrinsic Link Between PGRN and GBA1 D409V Mutation Dosage in Potentiating Gaucher Disease
Lin et al., Human Molecular Genetics. 2024.
https://doi.org/10.1093/hmg/ddae113
Gaucher disease (GD) is an autosomal recessive disorder and one of the most common lysosomal storage diseases. GD is caused by mutations in the GBA1 gene that encodes glucocerebrosidase (GCase), a lysosomal protein involved in glyocolipid metabolism. Progranulin (PGRN, encoded by GRN) is a modifier of GCase, and GRN mutant mice exhibit a GD-like phenotype. The researchers in this study aimed to understand the relationship between GCase and PGRN. They generated a panel of mice with various doses of the GBA1 D409V mutation in the GRN-/- background and characterized the animals’ disease progression using biochemical, pathological, transcriptomic, and neurobehavioral analyses. Homozygous (GRN-/-, GBA1 D409V/D409V) and hemizygous (GRN-/-, GBA1 D409V/null) animals exhibited profound inflammation and neurodegeneration compared to PG96 wild-type mice. Compared to homozygous mice, hemizygous mice showed more profound phenotypes (e.g., earlier onset, increased tissue fibrosis, shorter life span). These findings offer insights into GD pathogenesis and indicate that GD severity is affected by GBA1 D409V dosage and the presence of PGRN. Supported by ORIP (R21OD033660) and NINDS.
Macrophages Derived From Human Induced Pluripotent Stem Cells (iPSCs) Serve As a High-Fidelity Cellular Model for Investigating HIV-1, Dengue, and Influenza viruses
Yang et al., Journal of Virology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38323811/
Macrophages can be weaponized by viruses to host viral reproduction and support long-term persistence. The most common way of studying these cells is by isolating their precursors from donor blood and differentiating the isolated cells into macrophages. This method is costly and technically challenging, and it produces varying results. In this study, researchers confirmed that macrophages derived from iPSC cell lines—a model that is inexpensive, consistent, and modifiable by genome editing—are a suitable model for experiments involving HIV and other viruses. Macrophages derived from iPSCs are as susceptible to infection as macrophages derived from blood, with similar infection kinetics and phenotypes. This new model offers researchers an unlimited source of cells for studying viral biology. Supported by ORIP (R01OD034046, S10OD021601), NIAID, NIDA, NIGMS, and NHLBI.
Focused Ultrasound–Mediated Brain Genome Editing
Lao et al., PNAS. 2023.
https://www.pnas.org/doi/epdf/10.1073/pnas.2302910120
Gene editing in the brain has been challenging because of the restricted transport imposed by the blood–brain barrier (BBB). In this study, investigators described a safe and effective gene‑editing technique by using focused ultrasound (FUS) to transiently open the BBB for the transport of intravenously delivered CRISPR machinery to the brain in mice. By combining FUS with adeno-associated virus–mediated gene delivery, researchers can achieve more than 25% editing efficiency of particular cell types. This method has the potential to expand toolkit options for CRISPR delivery and opens opportunities for treating diseases of the brain, such as neurodegenerative disorders, with somatic genome editing. Supported by ORIP (U42OD026635) and NINDS.
Profiling Development of Abdominal Organs in the Pig
Gabriel et al., Scientific Reports. 2022.
https://www.doi.org/10.1038/s41598-022-19960-5
The pig is a model system for studying human development and disease due to its similarities to human anatomy, physiology, size, and genome. Moreover, advances in CRISPR gene editing have made genetically engineered pigs a viable model for the study of human pathologies and congenital anomalies. However, a detailed atlas illustrating pig development is necessary for identifying and modeling developmental defects. Here, the authors describe normal development of the pig abdominal system (i.e., kidney, liver, pancreas, spleen, adrenal glands, bowel, gonads) and compare them with congenital defects that can arise in gene-edited SAP130 mutant pigs. This atlas and the methods described here can be used as tools for identifying developmental pathologies of the abdominal organs in the pig at different stages of development. Supported by ORIP (U42OD011140), NHLBI, NIAID, NIBIB, NICHD, and NINDS.