Selected Grantee Publications
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.
Impaired Skeletal Development by Disruption of Presenilin-1 in Pigs and Generation of Novel Pig Models for Alzheimer's Disease
Uh et al., Journal of Alzheimer's Disease. 2024.
https://pubmed.ncbi.nlm.nih.gov/39177593/
This study explored the effects of presenilin 1 (PSEN1) disruption on vertebral malformations in male and female PSEN1 mutant pigs. Researchers observed significant skeletal impairments and early deaths in pigs with a PSEN1 null mutation, mirroring phenotypes seen in mouse models of Alzheimer’s disease (AD). This porcine model provides valuable insights into pathological hallmarks of PSEN1 mutations in AD, offering a robust platform of therapeutic exploration. The findings establish pigs as an essential translational model for AD, enabling advanced studies on pathophysiology and treatment development for human skeletal and neurological conditions. Supported by ORIP (U42OD011140), NHLBI, NIA, NIAID.
Gene Editing of Pigs to Control Influenza A Virus Infections
Kwon et al., Emerging Microbes & Infections. 2024.
https://pubmed.ncbi.nlm.nih.gov/39083026/
A reduction in the efficacy of vaccines and antiviral drugs for combating infectious diseases in agricultural animals has been observed. Generating genetically modified livestock species to minimize susceptibility to infectious diseases is of interest as an alternative approach. The researchers developed a homozygous transmembrane serine protease 2 (TMPRSS2) knockout (KO) porcine model to investigate resistance to two influenza A virus (IAV) subtypes, H1N1 and H3N2. TMPRSS2 KO pigs demonstrated diminished nasal cavity viral shedding, lower viral burden, and reduced microscopic lung pathology compared with wild-type (WT) pigs. In vitro culturing of primary bronchial epithelial cells (PBECs) demonstrated delayed viral replication in TMPRSS2 KO pigs compared with WT pigs. This study demonstrates the potential use of genetically modified pigs to mitigate IAV infections in pigs and limit transmission to humans. Supported by ORIP (U42OD011140), NHLBI, NIAID, and NIGMS.
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.
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.
Elevated Transferrin Receptor Impairs T Cell Metabolism and Function in Systemic Lupus Erythematosus
Voss et al., Science Immunol. 2023.
https://www.science.org/doi/10.1126/sciimmunol.abq0178
Systemic lupus erythematosus (SLE) is an autoimmune disease in which dysfunctional T cells exhibit abnormalities in metabolism. Investigators performed a CRISPR screen to examine mechanisms associated with the role of excess iron in dysfunctional T cells. The transferrin receptor (CD71) was identified as differentially critical for Type 1 T helper cells and inhibitory for induced regulatory T cells. Activated T cells induced CD71 and iron uptake, which was exaggerated in SLE-prone T cells. Disease severity correlated with CD71 expression in cells from male and female patients with SLE, and blocking CD71 in vitro enhanced interleukin 10 secretion. These findings suggest that T cell iron uptake via CD71 contributes to T cell dysfunction and can be targeted to limit SLE-associated pathology. Supported by ORIP (S10OD030264), NIAID, NCI, and NIDDK.
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.
Thresholds for Post-Rebound SHIV Control after CCR5 Gene-Edited Autologous Hematopoietic Cell Transplantation
Cardozo-Ojeda et al., eLife. 2021.
https://elifesciences.org/articles/57646
Investigators developed a mathematical model to project the minimum threshold of C-C chemokine receptor type 5 (CCR5) gene-edited cells necessary for a functional cure from HIV. This was based on blood T cell reconstitution and plasma simian-HIV (SHIV) dynamics from SHIV-1157ipd3N4-infected juvenile pig-tailed macaques that underwent autologous transplantation with CCR5 gene editing. The model predicts that viral control can be obtained following analytical treatment interruption (ATI) when: (1) transplanted hematopoietic stem and progenitor cells (HSPCs) are at least fivefold higher than residual endogenous HSPCs after total body irradiation and (2) the fraction of protected HSPCs in the transplant achieves a threshold (76–94%) sufficient to overcome transplantation-dependent loss of SHIV immunity. Under these conditions, if ATI is withheld until transplanted gene-modified cells engraft and reconstitute to a steady state, spontaneous viral control is projected to occur. Supported by ORIP (P51OD010425), NCATS and NIAID.