Selected Grantee Publications
Engineered Deletions of HIV Replicate Conditionally to Reduce Disease in Nonhuman Primates
Pitchai et al., Science. 2024.
https://pubmed.ncbi.nlm.nih.gov/39116226/
Current antiretroviral therapy (ART) for HIV is limited by the necessity for continuous administration. Discontinuation of ART leads to viral rebound. A therapeutic interfering particle (TIP) was developed as a novel single-administration HIV therapy using defective interfering particles. TIP treatment in two humanized mouse models demonstrated a significant reduction in HIV viral load. TIP intervention was completed 24 hours prior to a highly pathogenic simian immunodeficiency virus (SIV) challenge in a nonhuman primate (NHP) rhesus macaque infant model. Compared to untreated SIV infection, NHPs that received TIP treatment displayed no visible signs of SIV-induced AIDS and exhibited improved seroconversion and a significant survival advantage to the 30-week clinical endpoint. Peripheral blood mononuclear cells isolated from HIV-infected patients showed that TIP treatment reduced HIV outgrowth. This study demonstrates the potential use of a single-administration TIP for HIV treatment. Supported by ORIP (P51OD011092, U42OD010426), NCI, NIAID, and NIDA.
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.
RNA Landscapes of Brain and Brain-Derived Extracellular Vesicles in Simian Immunodeficiency Virus Infection and Central Nervous System Pathology
Huang et al., The Journal of Infectious Diseases. 2024.
https://pubmed.ncbi.nlm.nih.gov/38079216/
Brain tissue–derived extracellular vesicles (bdEVs) act locally in the central nervous system (CNS) and may indicate molecular mechanisms in HIV CNS pathology. Using brain homogenate (BH) and bdEVs from male pigtailed macaques, researchers identified dysregulated RNAs in acute and chronic infection. Most dysregulated messenger RNAs (mRNAs) in bdEVs reflected dysregulation in source BH, and these mRNAs are disproportionately involved in inflammation and immune responses. Additionally, several circular RNAs were differentially abundant in source tissue and might be responsible for specific differences in small RNA levels in bdEVs during simian immunodeficiency virus (SIV) infection. This RNA profiling shows potential regulatory networks in SIV infection and SIV-related CNS pathology. Supported by ORIP (U42OD013117), NCI, NIAID, NIDA, NIMH, and NINDS.
Genetic Diversity of 1,845 Rhesus Macaques Improves Genetic Variation Interpretation and Identifies Disease Models
Wang et al., Nature Communications. 2024.
https://www.nature.com/articles/s41467-024-49922-6
Nonhuman primates are ideal models for certain human diseases, including retinal and neurodevelopmental disorders. Using a reverse genetics approach, researchers profiled the genetic diversity of rhesus macaque populations across eight primate research centers in the United States and uncovered rhesus macaques carrying naturally occurring pathogenic mutations. They identified more than 47,000 single-nucleotide variants in 374 genes that had been previously linked with retinal and neurodevelopmental disorders in humans. These newly identified variants can be used to study human disease pathology and to test novel treatments. Supported by ORIP (P51OD011107, P51OD011106, P40OD012217, S10OD032189), NEI, NIAID, and NIMH.
A Revamped Rat Reference Genome Improves the Discovery of Genetic Diversity in Laboratory Rats
de Jong, Cell Genomics. 2024.
https://www.cell.com/cell-genomics/fulltext/S2666-979X(24)00069-7
Rattus norvegicus has been used in many fields of study related to human disease; its genome was sequenced shortly after the genomes of Homo sapiens and Mus musculus. Investigators report extensive analyses of the improvements in mRatBN7.2, compared with the previous version. They conducted a broad analysis of a whole-genome sequencing data set of 163 samples from 120 inbred rat strains and substrains. Several additional resources have been created. This new assembly and its associated resources create a more solid platform for research on the many dimensions of physiology, behavior, and pathobiology of rats and can provide more reliable and meaningful translation of findings to human populations. Supported by ORIP (R24OD024617), NHGRI, NHLBI, and NIDA.
Neutralizing Antibody Response to SARS‐CoV‐2 Bivalent mRNA Vaccine in SIV‐Infected Rhesus Macaques: Enhanced Immunity to XBB Subvariants by Two‐Dose Vaccination
Faraone, Journal of Medical Virology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38528837/
Researchers have shown that mRNA vaccination is less effective for people with advanced or untreated HIV infection, but data on the efficacy of mRNA vaccination against SARS-CoV-2 in this population are limited. Using rhesus macaques (sex not specified) with simian immunodeficiency virus (SIV), investigators examined the neutralizing antibody (nAb) response to SARS-CoV-2 vaccination. They found that administration of the bivalent vaccine alone can generate robust nAb titers against Omicron subvariants. Additionally, dams that received antiretroviral therapy had lower nAb titers than untreated dams. Overall, these findings highlight the need for further investigations into the nAb response in people with HIV. Supported by ORIP (P51OD011104), NCI, NIAID, NICHD, and NIMH.
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.
Molecular Basis of Human Trace Amine-Associated Receptor 1 Activation
Zilberg et al., Nature Communications. 2024.
https://www.nature.com/articles/s41467-023-44601-4
The authors reported the cryogenic electron microscopy structure of human trace amine-associated receptor 1 (hTAAR1, hTA1) signaling complex, a key modulator in monoaminergic neurotransmission, as well as its similarities and differences with other TAAR members and rodent TA1 receptors. This discovery has elucidated hTA1’s molecular mechanisms underlining the strongly divergent pharmacological properties of human and rodent TA1 and therefore will boost the translation of preclinical studies to clinical applications in treating disorders of dopaminergic dysfunction, metabolic disorders, cognitive impairment, and sleep-related dysfunction. Supported by ORIP (S10OD019994, S10OD026880, and S10OD030463), NIDA, NIGMS, NIMH, and NCATS.
GenomeMUSter Mouse Genetic Variation Service Enables Multitrait, Multipopulation Data Integration and Analysis
Ball et al., Genome Research. 2024.
https://genome.cshlp.org/content/34/1/145.long
Advances in genetics, including transcriptome-wide and phenome-wide association analysis methods, create compelling new opportunities for using fully reproducible and widely studied inbred mouse strains to characterize the polygenetic basis for individual differences in disease-related traits. Investigators developed an imputation approach and implemented data service to provide a broad and more comprehensive mouse variant resource. They evaluated the strain-specific imputation accuracy on a “held-out” test set that was not used in the imputation process. The authors present its application to multipopulation and multispecies analyses of complex trait variation in type 2 diabetes and substance use disorders and compare these results to human genetics studies. Supported by ORIP (U42OD010921, P40OD011102, R24OD035408), NCI, NIAAA, NIDA, and NIDCD.
Lymphoid Tissues Contribute to Plasma Viral Clonotypes Early After Antiretroviral Therapy Interruption in SIV-Infected Rhesus Macaques
Solis-Leal et al., Science Translational Medicine. 2023.
https://pubmed.ncbi.nlm.nih.gov/38091409/
Researchers are interested in better understanding the sources, timing, and mechanisms of HIV rebound that occurs after interruption of antiretroviral therapy (ART). Using rhesus macaques (sex not specified), investigators tracked barcoded simian immunodeficiency virus (SIV) clonotypes over time and among tissues. Among the tissues studied, mesenteric lymph nodes, inguinal lymph nodes, and spleen contained viral barcodes detected in plasma. Additionally, the authors reported that CD4+ T cells harbored the most viral RNA after ART interruption. These tissues are likely to contribute to viral reactivation and rebound after ART interruption, but further studies are needed to evaluate the relative potential contributions from other tissues and organs. Supported by ORIP (P51OD011104, P51OD011133, S10OD028732, S10OD028653), NCI, NIMH, and NINDS.