Selected Grantee Publications
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- 34 results found
- Nonhuman Primate Models
- COVID-19/Coronavirus
- Somatic Cell Genome Editing
Early Results of an Infant Model of Orthotopic Cardiac Xenotransplantation
Mitchell et al., Journal of Heart and Lung Transplantation. 2025.
https://pubmed.ncbi.nlm.nih.gov/39778609
This study evaluated the potential of genetically engineered pig hearts for human pediatric heart failure patients, with 11 infantile pig heart transplants performed in size-matched infant baboons (Papio anubis) (sex not specified). All grafts supported normal cardiac functions post-operatively, and six animals survived beyond 3 months. While early cardiac function was not a limiting factor for survival, systemic inflammation led to pulmonary edema and pleural effusions, which impeded long-term outcomes. These findings highlight the feasibility of cardiac xenotransplantation in infants and underscore the need for targeted therapies to manage inflammation and improve survival. Supported by ORIP (P40OD024628) and NHLBI.
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.
Lipid Nanoparticle-Mediated mRNA Delivery to CD34+ Cells in Rhesus Monkeys
Kim et al., Nature Biotechnology. 2024.
https://pubmed.ncbi.nlm.nih.gov/39578569
Blood cells, which are derived from hematopoietic stem cells (HSCs), promote pathologies including anemia, sickle cell disease, immunodeficiency, and metabolic disorders when dysfunctional. Because of the morbidity that results from the bone marrow mobilization and chemotherapy patient conditioning of current HSC therapies, novel treatment strategies that deliver RNA to HSCs are needed. Researchers found a lipid nanoparticle (LNP), LNP67, that delivers messenger RNA (mRNA) to murine HSCs in vivo and human HSCs ex vivo without the use of a cKit-targeting ligand. When tested in 7- to 8-month-old male and female rhesus monkeys, LNP67 successfully delivered mRNA to CD34+ cells and liver cells without adverse effects. These results show the potential translational relevance of an in vivo LNP–mRNA drug. Supported by ORIP (U42OD027094, P51OD011107), NIDDK, and NCATS.
A Single-Dose Intranasal Live-Attenuated Codon Deoptimized Vaccine Provides Broad Protection Against SARS-CoV-2 and Its Variants
Liu et al., Nature Communications. 2024.
https://pubmed.ncbi.nlm.nih.gov/39187479
Researchers developed an intranasal, single-dose, live-attenuated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) vaccine (CDO-7N-1) using codon deoptimization. This vaccine demonstrates broad protection against SARS-CoV-2 variants, with highly attenuated replication and minimal lung pathology across multiple in vivo passages. The vaccine induced robust mucosal and systemic neutralizing antibodies, as well as T-cell responses, in male and female hamsters, female K18-hACE2 mice, and male HFH4-hACE2 mice. In male and female cynomolgus macaques, CDO-7N-1 effectively prevented infection, reduced severe disease, and limited transmission of SARS-CoV-2 variants. This innovative approach offers potential advantages over traditional spike-protein vaccines by providing durable protection and targeting emerging variants to curb virus transmission. Supported by ORIP (K01OD026529).
Systematic Multi-trait AAV Capsid Engineering for Efficient Gene Delivery
Eid et al., Nature Communications. 2024.
https://doi.org/10.1038/s41467-024-50555-y
Engineering novel functions into proteins while retaining desired traits is a key challenge for developers of viral vectors, antibodies, and inhibitors of medical and industrial value. In this study, investigators developed Fit4Function, a generalizable machine learning (ML) approach for systematically engineering multi-trait adeno-associated virus (AAV) capsids. Fit4Function was used to generate reproducible screening data from a capsid library that samples the entire manufacturable sequence space. The Fit4Function data were used to train accurate sequence-to-function models, which were combined to develop a library of capsid candidates. Compared to AAV9, top candidates from the Fit4Function capsid library exhibited comparable production yields; more efficient murine liver transduction; up to 1,000-fold greater human hepatocyte transduction; and increased enrichment in a screen for liver transduction in macaques. The Fit4Function strategy enables prediction of peptide-modified AAV capsid traits across species and is a critical step toward assembling an ML atlas that predicts AAV capsid performance across dozens of traits. Supported by ORIP (P51OD011107, U42OD027094), NIDDK, NIMH, and NINDS.
AAV5 Delivery of CRISPR/Cas9 Mediates Genome Editing in the Lungs of Young Rhesus Monkeys
Liang et al., Human Gene Therapy. 2024.
https://pubmed.ncbi.nlm.nih.gov/38767512/
Genome editing in somatic cells and tissues has the potential to provide long-term expression of therapeutic proteins to treat a variety of genetic lung disorders. However, delivering genome-editing machinery to disease-relevant cell types in the lungs of primates has remained a challenge. Investigators of this article are participating in the NIH Somatic Cell Genome Editing Consortium. Herein, they demonstrate that intratracheal administration of a dual adeno-associated virus type 5 vector encoding CRISPR/Cas9 can mediate genome editing in rhesus (male and female) airways. Up to 8% editing was observed in lung lobes, including a housekeeping gene, GAPDH, and a disease-related gene, angiotensin-converting enzyme 2. Using single-nucleus RNA-sequencing, investigators systematically characterized cell types transduced by the vector. Supported by ORIP (P51OD01110, U42OD027094, S10OD028713), NCATS, NCI, and NHLBI.
Engineered IgM and IgG Cleaving Enzymes for Mitigating Antibody Neutralization and Complement Activation in AAV Gene Transfer
Smith et al., Molecular Therapy. 2024.
https://www.sciencedirect.com/science/article/pii/S1525001624003058?via%3Dihub=
Recombinant adeno-associated viral (AAV) vectors have emerged as the leading platform for therapeutic gene transfer, but systemic dosing of AAV vectors poses potential risk of adverse side effects, including complement activation triggered by anti-capsid immunity. In this study, investigators discovered an IgM cleaving enzyme (IceM) that degrades human IgM, a key trigger in the anti-AAV immune cascade. They engineered a fusion enzyme (IceMG) with dual proteolytic activity against human IgM and IgG. Antisera from animals treated with IceMG show decreased ability to neutralize AAV and activate complement. These studies have implications for improving the safety of AAV gene therapies and offer broader applications, including for organ transplantation and autoimmune diseases. Supported by ORIP (P51OD011107, U42OD027094), NHLBI, and NIAID.
Pathogenesis and Virulence of Coronavirus Disease: Comparative Pathology of Animal Models for COVID-19
Kirk et al., Virulence. 2024.
https://pubmed.ncbi.nlm.nih.gov/38362881
Researchers have used animal models that can replicate clinical and pathologic features of severe human coronavirus infections to develop novel vaccines and therapeutics in humans. The purpose of this review is to describe important animal models for COVID-19, with an emphasis on comparative pathology. The highlighted species included mice, ferrets, hamsters, and nonhuman primates. Knowledge gained from studying these animal models can help inform appropriate model selection for disease modeling, as well as for vaccine and therapeutic developments. Supported by ORIP (T32OD010993) and NIAID.
The Impact of SIV-Induced Immunodeficiency on Clinical Manifestation, Immune Response, and Viral Dynamics in SARS-CoV-2 Coinfection
Melton et al., bioRxiv. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10680717/
The effects of immunodeficiency caused by chronic HIV infection on COVID-19 have not been directly addressed in a controlled setting. Investigators conducted a pilot study in which two pigtail macaques (PTMs) chronically infected with SIVmac239 were exposed to SARS-CoV-2 and compared with SIV-naive PTMs infected with SARS-CoV-2. Despite the marked decrease in CD4+ T cells in the SIV-positive animals prior to exposure to SARS-CoV-2, investigators found that disease progression, viral persistence, and evolution of SARS-CoV-2 were comparable to the control group. These findings suggest that SIV-induced immunodeficiency alters the immune response to SARS-CoV-2 infection, leading to impaired cellular and humoral immunity. However, this impairment does not significantly alter the course of infection. Supported by ORIP (P51OD011104, U42OD013117, S10OD026800, S10OD030347) and NIAID.
Cerebrospinal Fluid Protein Markers Indicate Neuro-Damage in SARS-CoV-2-Infected Nonhuman Primates
Maity et al., Molecular & Cellular Proteomics. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9981268/
In this study, researchers examined the proteins expressed in cerebrospinal fluid (CSF) in nonhuman primates (NHPs) to better understand how COVID-19 infection can result in brain pathology, a common outcome. The study found that even in NHPs with minimal or mild COVID‑19, CSF proteins were significantly dysregulated compared with uninfected NHPs. Furthermore, the most affected proteins were enriched in the same brain regions that show lesions after COVID-19 infection, including the cerebral cortex, basal ganglia, and brain stem. Collectively, these regions have wide-ranging control over such crucial functions as cognition, motor control, and breathing, showing how even mild COVID-19 infection can result in significant neurological impairment. Supported by ORIP (P51OD011104, S10OD032453), NIGMS, NCI, and NICHD.