Selected Grantee Publications
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- 13 results found
- Swine Models
- Immunology
- Pediatrics
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.
Single-Cell Transcriptomics Predict Novel Potential Regulators of Acute Epithelial Restitution in the Ischemia-Injured Intestine
Rose et al., American Journal of Physiology-Gastrointestinal and Liver Physiology. 2025.
https://pubmed.ncbi.nlm.nih.gov/39853303
Following ischemia in the small intestine, early barrier restoration relies on epithelial restitution to reseal the physical barrier and prevent sepsis. Pigs share a similar gastrointestinal anatomy, physiology, and microbiota with humans. Researchers used neonatal and juvenile, 2- to 6-week-old male and female Yorkshire cross pigs to determine upstream regulators of restitution. Single-cell sequencing of ischemia-injured epithelial cells demonstrated two sub-phenotypes of absorptive enterocytes, with one subset presenting a restitution phenotype. Colony-stimulating factor-1 (CSF1) was the only predicted upstream regulator expressed in juvenile jejunum compared with neonatal jejunum. An in vitro scratch wound assay using IPEC-J2 cells showed that BLZ945, a colony-stimulating factor 1 receptor antagonist, inhibited restitution. Ex vivo ischemia-injured neonatal pig jejunum treated with exogenous CSF1 displayed increased barrier function. This study could inform future research focused on developing novel therapeutics for intestinal barrier injury in patients. Supported by ORIP (T32OD011130, K01OD028207), NCATS, NICHD, and NIDDK.
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.
Fetal Bone Engraftment Reconstitutes the Immune System in Pigs With Severe Combined Immunodeficiency
Monarch et al., Lab Animal. 2024.
https://pubmed.ncbi.nlm.nih.gov/39289566/
A valuable preclinical model for studying immune-related pathologies is the severe combined immunodeficiency (SCID) pig through modification of recombination activating gene 2 (RAG2) and interleukin-2 receptor-γ (IL2RG). RAG2/IL2RG double knockout SCID pigs are hard to maintain for breeding and long-term studies because their life span is 8 weeks or less. The researchers investigated fetal allograft transplantation derived from immunocompetent pigs as a strategy for reconstituting the immune system of SCID pigs and promoting survival. Following fetal allograft, SCID pigs demonstrated increased levels of lymphocytes. SCID pigs that received the fetal allograft demonstrated improved body condition and extended life span compared with nonrecipient SCID littermates. This study demonstrates the potential use of fetal allograft transplantation to extend the life span of SCID pigs to breeding age to reduce the resources used to maintain this model for biomedical research. Supported by ORIP (U42OD011140, R21OD027062).
Surgical Protocol for Partial Heart Transplantation in Growing Piglets
Medina, World Journal for Pediatric and Congenital Heart Surgery. 2024.
https://pubmed.ncbi.nlm.nih.gov/38780414/
Researchers are interested in using partial heart transplantation (i.e., only the part of the heart containing the necessary heart valve is transplanted) to deliver growing heart valve implants. This novel technique allows partial heart transplants to grow, similar to the valves in heart transplants. More work is needed, however, to understand the underlying biological mechanisms of this approach and achieve progress in clinical care. In the present study, the authors present a surgical protocol for partial heart transplantation in growing piglets. This model will enable other researchers to seek fundamental knowledge about the nature of partial heart transplants. Supported by ORIP (U42OD011140) and NHLBI.
Ultrasoft Platelet-Like Particles Stop Bleeding in Rodent and Porcine Models of Trauma
Nellenbach et al., Science Translational Medicine. 2024.
https://www.science.org/doi/10.1126/scitranslmed.adi4490
Platelet transfusions are the current standard of care to control bleeding in patients following acute trauma, but their use is limited by short shelf life and limited supply. Immunogenicity and contamination risks also are a concern. Using ultrasoft and highly deformable nanogels coupled to fibrin-specific antibody fragments, researchers developed synthetic platelet-like particles (PLPs) as an alternative for immediate treatment of uncontrolled bleeding. They report that PLPs reduced bleeding and facilitated healing of injured tissue in mice, rat, and swine models (sex not specified) for traumatic injury. These findings can inform further translational studies of synthetic PLPs for the treatment of uncontrolled bleeding in a trauma setting. Supported by ORIP (T32OD011130) and NHLBI.
Consistent Survival in Consecutive Cases of Life-Supporting Porcine Kidney Xenotransplantation Using 10GE Source Pigs
Eiseson et al., Nature Communications. 2024.
https://pubmed.ncbi.nlm.nih.gov/38637524/
Xenotransplantation offers potential for addressing organ donor shortages, and the U.S. Food and Drug Administration recently issued guidance on a regulatory path forward. Researchers have performed studies in this area, but concerns have been expressed about safe clinical translation of their results (e.g., survival, preclinical procurement, immunosuppression, clinical standards of care). In this study, the authors report consistent survival in consecutive cases of kidney xenotransplantation from pigs (male and female) to baboons (male and female). The authors propose that their findings serve as proof of concept for prevention of xenograft rejection in recipients of genetically modified porcine kidneys. This work offers insights for immunosuppression regimens for first-in-human clinical trials. Supported by ORIP (P40OD024628).
Pigs in Transplantation Research and Their Potential as Sources of Organs in Clinical Xenotransplantation
Raza et al., Comparative Medicine. 2024.
https://pubmed.ncbi.nlm.nih.gov/38359908/
The pig has now gained importance as a potential source of organs for clinical xenotransplantation. When an organ from a wild-type (i.e., genetically unmodified) pig is transplanted into an immunosuppressed nonhuman primate, a vigorous host immune response causes hyperacute rejection (within minutes or hours). This response has been largely overcome by (1) extensive gene editing of the organ-source pig and (2) administration to the recipient of novel immunosuppressive therapy based on blockade of the CD40/CD154 T-cell costimulation pathway. The combination of gene editing and novel immunosuppressive therapy has extended life-supporting pig kidney graft survival to greater than 1 year and of pig heart survival to up to 9 months. This review briefly describes the techniques of gene editing, the potential risks of transfer of porcine endogenous retroviruses with the organ, and the need for breeding and housing of donor pigs under biosecure conditions. Supported by ORIP (P40OD024628) and NIAID.
Effects of Acute Femoral Head Ischemia on the Growth Plate and Metaphysis in a Piglet Model of Legg-Calvé-Perthes Disease
Armstrong et al., Osteoarthritis and Cartilage. 2023.
https://pubmed.ncbi.nlm.nih.gov/36696941/
Legg-Calvé-Perthes disease (LCPD) can lead to permanent deformity of the femoral head and premature osteoarthritis, but the underlying cause remains unknown. More work is needed to determine optimal treatment methods for LCPD. Using a piglet model for LCPD, researchers assessed the effects of acute femoral head ischemia on the proximal femoral growth plate and metaphysis. They reported that alterations to the growth plate zones and metaphysis occurred by 2 days post-ischemia and persisted at 7 days post-ischemia. These findings suggest that growth disruption may occur sooner after the onset of ischemia than researchers had hypothesized previously. Supported by ORIP (T32OD010993, K01OD021293), NIAMS, and NCATS.
Naturally Occurring Osteochondrosis Latens Lesions Identified by Quantitative and Morphological 10.5 T MRI in Pigs
Armstrong et al., Journal of Orthopaedic Research. 2023.
https://pubmed.ncbi.nlm.nih.gov/35716161/
Juvenile osteochondritis dissecans (JOCD) is a pediatric orthopedic disorder that is associated with pain and gait deficits. JOCD lesions form in the knee, elbow, and ankle joints and can progress to early-onset osteoarthritis. In this study, researchers used a noninvasive magnetic resonance imaging (MRI) method to identify naturally occurring lesions in intact knee and elbow joints of juvenile pigs. This work can be applied to noninvasive identification and monitoring of early JOCD lesions and determination of risk factors that contribute to their progression in children. Supported by ORIP (K01OD021293, T32OD010993), NIAMS, and NIBIB.