Selected Grantee Publications
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- 10 results found
- Swine Models
- 2023
- 2021
DAZL Knockout Pigs as Recipients for Spermatogonial Stem Cell Transplantation
Lara et al., Cells. 2023.
https://pubmed.ncbi.nlm.nih.gov/37947660/
Spermatogonial stem cell (SSC) transplantation is a technique that holds potential for addressing male infertility, as well as generation of genetically modified animal models. DAZL (Deleted in Azoospermia–Like) is a conserved RNA-binding protein important for germ cell development, and DAZL knockout (KO) causes defects in germ cell commitment and differentiation. Investigators characterized DAZL-KO pigs as SSC transplantation recipients. DAZL-KO pigs support donor-derived spermatogenesis following SSC transplantation, but low spermatogenic efficiency currently limits their use for the production of offspring. Supported by ORIP (R01OD016575) and NIGMS.
A LGR5 Reporter Pig Model Closely Resembles Human Intestine for Improved Study of Stem Cells in Disease
Schaaf et al., The FASEB Journal. 2023.
https://faseb.onlinelibrary.wiley.com/doi/10.1096/fj.202300223R
The constant epithelial regeneration in the intestine is the sole responsibility of intestinal epithelial stem cells (ISCs), which reside deep in the intestinal crypt structures. To effectively study ISCs, tools to identify this cell population are necessary. This study validates ISC isolation in a new porcine Leucine Rich Repeat Containing G Protein–Coupled Receptor 5 (LGR5) reporter line and demonstrates the use of these pigs as a novel colorectal cancer model. Overall, this novel porcine model provides critical advancement to the field of translational gastrointestinal research. Supported by ORIP (R21OD019738, K01OD019911), NCI, and NIDDK.
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.
Challenges and Considerations During In Vitro Production of Porcine Embryos
Chen et al., Cells. 2021.
https://pubmed.ncbi.nlm.nih.gov/34685749/
Genetically modified pigs have become valuable tools for generating advances in animal agriculture and human medicine. Importantly, in vitro production and manipulation of embryos is an essential step in the process of creating porcine models. As the in vitro environment is still suboptimal, it is imperative to examine the porcine embryo culture system from several angles to identify methods for improvement. Understanding metabolic characteristics of porcine embryos and considering comparisons with other mammalian species is useful for optimizing culture media formulations. Furthermore, stressors arising from the environment and maternal or paternal factors must be taken into consideration to produce healthy embryos in vitro. In this review, Chen et al progress stepwise through in vitro oocyte maturation, fertilization, and embryo culture in pigs to assess the status of current culture systems and address points where improvements can be made. Supported by ORIP (U42OD011140).
Limited Expansion of Human Hepatocytes in FAH/RAG2-Deficient Swine
Nelson et al., Tissue Engineering – Part A. 2021.
https://pubmed.ncbi.nlm.nih.gov/34309416/
The mammalian liver's regenerative ability has led researchers to engineer animals as incubators for expansion of human hepatocytes. Nelson et al. engineered immunodeficient swine to support expansion of human hepatocytes and identify barriers to their clinical application. Immunodeficient swine were engineered by knockout of the recombinase-activating gene 2 (RAG2) and fumarylacetoacetate hydrolase (FAH). Immature human hepatocytes (ihHCs) were injected into fetal swine by intrauterine cell transplantation (IUCT) at day 40 of gestation. They identified the mechanism of the eventual graft rejection by the intact NK cell population. They confirmed the presence of residual adaptive immunity in this model of immunodeficiency. Supported by ORIP (U42OD011140).
Mineralocorticoid Receptor Blockade Normalizes Coronary Resistance in Obese Swine Independent of Functional Alterations in Kv Channels
Goodwill et al., Basic Research in Cardiology. 2021.
https://pubmed.ncbi.nlm.nih.gov/34018061/
Impaired coronary microvascular function (e.g., reduced dilation and coronary flow reserve) predicts cardiac mortality in obesity. Mineralocorticoid receptor (MR) antagonism improves coronary microvascular function in obese humans and animals. Inhibition of Kv channels reduced coronary blood flow and augmented coronary resistance under baseline conditions in lean but not obese swine and had no impact on hypoxemic coronary vasodilation. MR blockade prevented obesity-associated coronary arteriolar stiffening independent of cardiac capillary density and changes in cardiac function. These data indicate that chronic MR inhibition prevents increased coronary resistance in obesity independent of Kv channel function and is associated with mitigation of obesity-mediated coronary arteriolar stiffening. Supported by ORIP (U42OD011140, S10OD023438), NHLBI, and NIBIB.
Establishing an Immunocompromised Porcine Model of Human Cancer for Novel Therapy Development with Pancreatic Adenocarcinoma and Irreversible Electroporation
Hendricks-Wenger et al., Scientific Reports. 2021.
https://pubmed.ncbi.nlm.nih.gov/33828203/
Efficacious interventions to treat pancreatic cancer lack a preclinical model to recapitulate patients' anatomy and physiology. The authors developed RAG2/IL2RG deficient pigs using CRISPR/Cas9 with the novel application of cancer xenograft studies of human pancreatic adenocarcinoma. These pigs were successfully generated using on-demand genetic modifications in embryos. Human Panc01 cells injected into the ears of RAG2/IL2RG deficient pigs demonstrated 100% engraftment. The electrical properties and response to irreversible electroporation of the tumor tissue were found to be similar to excised human pancreatic cancer tumors. This model will be useful to bridge the gap of translating therapies from the bench to clinical application. Supported by ORIP (R21OD027062), NIBIB, and NCI.
Interneuron Origins in the Embryonic Porcine Medial Ganglionic Eminence
Casalia et al., Journal of Neuroscience. 2021.
https://pubmed.ncbi.nlm.nih.gov/33637558/
The authors report that transcription factor expression patterns in porcine embryonic subpallium are similar to rodents. Their findings reveal that porcine embryonic MGE progenitors could serve as a valuable source for interneuron-based xenotransplantation therapies. They demonstrate that porcine medial ganglionic eminence exhibits a distinct transcriptional and interneuron-specific antibody profile, in vitro migratory capacity, and are amenable to xenotransplantation. This is the first comprehensive examination of embryonic interneuron origins in the pig; because a rich neurodevelopmental literature on embryonic mouse medial ganglionic eminence exists (with some additional characterizations in monkeys and humans), their work allows direct neurodevelopmental comparisons with this literature. Supported by ORIP (U42OD011140) and NINDS.
A Pulsatile Release Platform Based on Photo-Induced Imine-Crosslinking Hydrogel Promotes Scarless Wound Healing
Zhang et al., Nature Communications. 2021.
https://pubmed.ncbi.nlm.nih.gov/33723267/
Skin wound healing is a dynamic and interactive process involving the collaborative efforts of growth factors, extracellular matrix (ECM), and different tissue and cell lineages. Although accumulating studies with a range of different model systems have increased our understanding of the cellular and molecular basis underlying skin scar formation, they have not been effectively translated to therapy. Development of effective therapeutic approaches for skin scar management is urgently needed. In this study, team of investigators devise a water-oil-water double emulsion strategy to encapsulate proteins within a photo-crosslinkable poly-lactic-co-glycolic acid (PLGA) shell, which can produce microcapsules with pulsatile drug release kinetics after administration. The results show that pulsatile release of the TGF-β inhibitor can accelerate skin wound closure while suppressing scarring in murine skin wounds and large animal preclinical models, suggesting that it could be an effective approach to achieve scarless wound healing in skin. Supported by ORIP (R01OD023700).