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.
Amphiphilic Shuttle Peptide Delivers Base Editor Ribonucleoprotein to Correct the CFTR R553X Mutation in Well-Differentiated Airway Epithelial Cells
Kulhankova et al., Nucleic Acids Research. 2024.
https://academic.oup.com/nar/article/52/19/11911/7771564?login=true
Effective translational delivery strategies for base editing applications in pulmonary diseases remain a challenge because of epithelial cells lining the intrapulmonary airways. The researchers demonstrated that the endosomal leakage domain (ELD) plays a crucial role in gene editing ribonucleoprotein (RNP) delivery activity. A novel shuttle peptide, S237, was created by flanking the ELD with poly glycine-serine stretches. Primary airway epithelia with the cystic fibrosis transmembrane conductance regulator (CFTR) R533X mutation demonstrated restored CFTR function when treated with S237-dependent ABE8e-Cas9-NG RNP. S237 outperformed the S10 shuttle peptide at Cas9 RNP delivery in vitro and in vivo using primary human bronchial epithelial cells and transgenic green fluorescent protein neonatal pigs. This study highlights the efficacy of S237 peptide–mediated RNP delivery and its potential as a therapeutic tool for the treatment of cystic fibrosis. Supported by ORIP (U42OD027090, U42OD026635), NCATS, NHGRI, NHLBI, NIAID, NIDDK, and NIGMS.
Deletion of Mouse Lysyl Oxidase in Megakaryocytes Affects Bone Properties in a Sex-Dependent Manner
Karagianni, Cell. 2024.
https://pubmed.ncbi.nlm.nih.gov/38635757/
Lysyl oxidase (LOX) is a facilitator of extracellular matrix cross-linking, and the importance of LOX in bone formation has been addressed in both in vitro and in vivo studies. Using newly developed megakaryocyte-specific LOX knockout mice, the researchers show that LOX expressed in these scarce bone marrow cells leads to changes in bone volume and mechanical strength in male mice; however, no significant changes were observed within the female experimental groups. The authors’ findings suggest that sex hormones could contribute to differences within these dynamics. Supported by ORIP (K01OD025290) and NIAMS.
Disruption of Myelin Structure and Oligodendrocyte Maturation in a Macaque Model of Congenital Zika Infection
Tisoncik-Go et al., Nature Communications. 2024.
https://www.nature.com/articles/s41467-024-49524-2
Maternal infection during pregnancy can have severe consequences on fetal development and survival. Using a pigtail macaque model for Zika virus infection, researchers show that in utero exposure of a fetus to Zika virus due to maternal infection results in significantly decreased myelin formation around neurons. Myelin is a protective sheath that forms around neurons and is required for brain processing speed. This study suggests that reduced myelin resulting from Zika infection in utero is likely a contributing factor to severe deficits in brain development and microcephaly. Supported by ORIP (P51OD010425), NEI, and NIAID.
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.
Loss of Lymphatic IKKα Disrupts Lung Immune Homeostasis, Drives BALT Formation, and Protects Against Influenza
Cully et al., Immunohorizons. 2024.
https://pubmed.ncbi.nlm.nih.gov/39007717/
Tertiary lymphoid structures (TLS) have context-specific roles, and more work is needed to understand how they function in separate diseases to drive or reduce pathology. Researchers showed previously that lymph node formation is ablated in mice constitutively lacking IκB kinase alpha (IKKα) in lymphatic endothelial cells (LECs). In this study, they demonstrated that loss of IKKα in lymphatic endothelial cells leads to the formation of bronchus-associated lymphoid tissue in the lung. Additionally, they showed that male and female mice challenged with influenza A virus (IAV) exhibited markedly improved survival rates and reduced weight loss, compared with littermate controls. They concluded that ablating IKKα in this tissue reduces the susceptibility of the mice to IAV infection through a decrease in proinflammatory stimuli. This work provides a new model to explore the mechanisms of TLS formation and the immunoregulatory function of lung lymphatics. Supported by ORIP (T35OD010919), NHLBI, NIAID, and NIAMS.
Time of Sample Collection Is Critical for the Replicability of Microbiome Analyses
Allaband et al., Nature Metabolism. 2024.
https://pubmed.ncbi.nlm.nih.gov/38951660/
Lack of replicability remains a challenge in microbiome studies. As the microbiome field moves from descriptive and associative research to mechanistic and interventional studies, being able to account for all confounding variables in the experimental design will be critical. Researchers conducted a retrospective analysis of 16S amplicon sequencing studies in male mice. They report that sample collection time affects the conclusions drawn from microbiome studies. The lack of consistency in the time of sample collection could help explain poor cross-study replicability in microbiome research. The effect of diurnal rhythms on the outcomes and study designs of other fields is unknown but is likely significant. Supported by ORIP (T32OD017863), NCATS, NCI, NHLBI, NIAAA, NIAID, NIBIB, NIDDK, and NIGMS.
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.