Selected Grantee Publications
Multimodal Analysis of Dysregulated Heme Metabolism, Hypoxic Signaling, and Stress Erythropoiesis in Down Syndrome
Donovan et al., Cell Reports. 2024.
https://pubmed.ncbi.nlm.nih.gov/39120971
Down syndrome (DS), a genetic condition caused by the presence of an extra copy of chromosome 21, is characterized by intellectual and developmental disability. Infants with DS often suffer from low oxygen saturation, and DS is associated with obstructive sleep apnea. Investigators assessed the role that hypoxia plays in driving health conditions that are comorbid with DS. A multiomic analysis showed that people with DS exhibit elevated heme metabolism and activated stress erythropoiesis, which are indicators of chronic hypoxia; these results were recapitulated in a mouse model for DS. This study identified hypoxia as a possible mechanism underlying several conditions that co-occur with DS, including congenital heart defects, seizure disorders, autoimmune disorders, several leukemias, and Alzheimer's disease. Supported by ORIP (R24OD035579), NCATS, NCI, and NIAID.
Transcriptomic Analysis of Skeletal Muscle Regeneration Across Mouse Lifespan Identifies Altered Stem Cell States
Walter et al., Nature Aging. 2024.
https://pubmed.ncbi.nlm.nih.gov/39578558
Age-related skeletal muscle regeneration dysfunction is poorly understood. Using single-cell transcriptomics and high-resolution spatial transcriptomics, researchers evaluated factors contributing to age-related decline in skeletal muscle regeneration after injury in young, old, and geriatric male and female mice (5, 20, and 26 months old). Eight immune cell types were identified and associated with age-related dynamics and distinct muscle stem cell states specific to old and geriatric tissue. The findings emphasize the role of extrinsic and intrinsic factors, including cellular senescence, in disrupting muscle repair. This study provides a spatial and molecular framework for understanding regenerative decline and cellular heterogeneity in aging skeletal muscle. Supported by ORIP (F30OD032097), NIA, NIAID, NIAMS, NICHD, and NIDA.
Extended Survival of 9- and 10-Gene-Edited Pig Heart Xenografts With Ischemia Minimization and CD154 Costimulation Blockade-Based Immunosuppression
Chaban et al., The Journal of Heart and Lung Transplantation. 2024.
https://pubmed.ncbi.nlm.nih.gov/39097214
Heart transplantations are severely constrained from the shortage of available organs derived from human donors. Xenotransplantation of hearts from gene-edited (GE) pigs is a promising way to address this problem. Researchers evaluated GE pig hearts with varying knockouts and human transgene insertions. Human transgenes are introduced to mitigate important physiological incompatibilities between pig cells and human blood. Using a baboon heterotopic cardiac transplantation model, one female and seven male specific-pathogen-free baboons received either a 3-GE, 9-GE, or 10-GE pig heart with an immunosuppression regimen targeting CD40/CD154. Early cardiac xenograft failure with complement activation and multifocal infarcts were observed with 3-GE pig hearts, whereas 9- and 10-GE pig hearts demonstrated successful graft function and prolonged survival. These findings show that one or more transgenes of the 9- and 10-GE pig hearts with CD154 blockade provide graft protection in this preclinical model. Supported by ORIP (U42OD011140) and NIAID.
Immune Perturbation Following SHIV Infection Is Greater in Newborn Macaques Than in Infants
Shapiro et al., JCI Insight. 2024.
https://pubmed.ncbi.nlm.nih.gov/39190496
This study investigates immune perturbation following simian-human immunodeficiency virus (SHIV) infection in newborn and infant male and female rhesus macaques, highlighting significant differences in pathogenesis. Although plasma viremia and lymph node viral DNA were similar, newborns exhibited higher viral DNA levels in gut and lymphoid tissues 6–10 weeks postinfection than infants. Additionally, newborns showed greater immune alterations, with skewed monocyte and CD8+ T-cell profiles and minimal type I interferon responses. These findings suggest age-dependent immunological responses to SHIV and underscore the vulnerability of newborns to HIV-related pathogenesis, providing insights into immune development and pediatric HIV management. Supported by ORIP (P51OD011092, U42OD023038, U42OD010426) and NIAID.
Effect of Metabolic Status on Response to SIV Infection and Antiretroviral Therapy in Nonhuman Primates
Webb et al., JCI Insight. 2024.
https://pubmed.ncbi.nlm.nih.gov/39115937
This study examines how metabolic health influences the efficacy of antiretroviral therapy (ART). Using lean and obese male rhesus macaques, researchers explored the progression of simian immunodeficiency virus (SIV) infection. Obese macaques with metabolic dysfunction experienced more rapid disease progression and had a diminished response to ART than lean macaques. This study suggests metabolic health plays a significant role in HIV progression and treatment outcomes, highlighting the importance of managing metabolic conditions in people with HIV. Supported by ORIP (P51OD011092, S10OD025002), NIAID, and NIDDK.
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.