In JoVE (1)
Other Publications (7)
- American Journal of Physiology. Gastrointestinal and Liver Physiology
- Translational Research : the Journal of Laboratory and Clinical Medicine
- American Journal of Veterinary Research
- American Journal of Physiology. Gastrointestinal and Liver Physiology
- Cellular and Molecular Gastroenterology and Hepatology
- Veterinary Radiology & Ultrasound : the Official Journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association
- PloS One
Articles by Liara M Gonzalez in JoVE
Intestinal Stem Cell Isolation and Culture in a Porcine Model of Segmental Small Intestinal Ischemia Amy Stieler Stewart1, John M Freund1, Anthony T Blikslager1, Liara M Gonzalez1 1Department of Clinical Sciences, North Carolina State University This protocol will enable readers to successfully establish a porcine model of segmental intestinal ischemia and subsequently isolate and culture intestinal stem cells for the study of epithelial repair following injury.
Other articles by Liara M Gonzalez on PubMed
Animal Models of Ischemia-reperfusion-induced Intestinal Injury: Progress and Promise for Translational Research American Journal of Physiology. Gastrointestinal and Liver Physiology. | Pubmed ID: 25414098 Research in the field of ischemia-reperfusion injury continues to be plagued by the inability to translate research findings to clinically useful therapies. This may in part relate to the complexity of disease processes that result in intestinal ischemia but may also result from inappropriate research model selection. Research animal models have been integral to the study of ischemia-reperfusion-induced intestinal injury. However, the clinical conditions that compromise intestinal blood flow in clinical patients ranges widely from primary intestinal disease to processes secondary to distant organ failure and generalized systemic disease. Thus models that closely resemble human pathology in clinical conditions as disparate as volvulus, shock, and necrotizing enterocolitis are likely to give the greatest opportunity to understand mechanisms of ischemia that may ultimately translate to patient care. Furthermore, conditions that result in varying levels of ischemia may be further complicated by the reperfusion of blood to tissues that, in some cases, further exacerbates injury. This review assesses animal models of ischemia-reperfusion injury as well as the knowledge that has been derived from each to aid selection of appropriate research models. In addition, a discussion of the future of intestinal ischemia-reperfusion research is provided to place some context on the areas likely to provide the greatest benefit from continued research of ischemia-reperfusion injury.
Porcine Models of Digestive Disease: the Future of Large Animal Translational Research Translational Research : the Journal of Laboratory and Clinical Medicine. | Pubmed ID: 25655839 There is increasing interest in nonrodent translational models for the study of human disease. The pig, in particular, serves as a useful animal model for the study of pathophysiological conditions relevant to the human intestine. This review assesses currently used porcine models of gastrointestinal physiology and disease and provides a rationale for the use of these models for future translational studies. The pig has proven its utility for the study of fundamental disease conditions such as ischemia-reperfusion injury, stress-induced intestinal dysfunction, and short bowel syndrome. Pigs have also shown great promise for the study of intestinal barrier function, surgical tissue manipulation and intervention, as well as biomaterial implantation and tissue transplantation. Advantages of pig models highlighted by these studies include the physiological similarity to human intestine and mechanisms of human disease. Emerging future directions for porcine models of human disease include the fields of transgenics and stem cell biology, with exciting implications for regenerative medicine.
Characterization of Discrete Equine Intestinal Epithelial Cell Lineages American Journal of Veterinary Research. | Pubmed ID: 25815577 To characterize epithelial cells of the small intestine and colon in horses without clinical gastrointestinal abnormalities with an emphasis on the stem cell niche constituents.
Ductular and Proliferative Response of Esophageal Submucosal Glands in a Porcine Model of Esophageal Injury and Repair American Journal of Physiology. Gastrointestinal and Liver Physiology. | Pubmed ID: 28572084 Esophageal injury is a risk factor for diseases such as Barrett's esophagus (BE) and esophageal adenocarcinoma. To improve understanding of signaling pathways associated with both normal and abnormal repair, animal models are needed. Traditional rodent models of esophageal repair are limited by the absence of esophageal submucosal glands (ESMGs), which are present in the human esophagus. Previously, we identified acinar ductal metaplasia in human ESMGs in association with both esophageal injury and cancer. In addition, the SOX9 transcription factor has been associated with generation of columnar epithelium and the pathogenesis of BE and is present in ESMGs. To test our hypothesis that ESMGs activate after esophageal injury with an increase in proliferation, generation of a ductal phenotype, and expression of SOX9, we developed a porcine model of esophageal injury and repair using radiofrequency ablation (RFA). The porcine esophagus contains ESMGs, and RFA produces a consistent and reproducible mucosal injury in the esophagus. Here we present a temporal assessment of this model of esophageal repair. Porcine esophagus was evaluated at 0, 6, 18, 24, 48, and 72 h and 5 and 7 days following RFA and compared with control uninjured esophagus. Following RFA, ESMGs demonstrated an increase in ductal phenotype, echoing our prior studies in humans. Proliferation increased in both squamous epithelium and ESMGs postinjury with a prominent population of SOX9-positive cells in ESMGs postinjury. This model promises to be useful in future experiments evaluating mechanisms of esophageal repair. A novel porcine model of injury and repair using radiofrequency ablation has been developed, allowing for reproducible injury to the esophagus to study repair in an animal model with esophageal submucosal glands, a key anatomical feature and missing in rodent models but possibly harboring progenitor cells. There is a strong translational component to this porcine model given the anatomical and physiological similarities between pigs and humans.
Porcine Esophageal Submucosal Gland Culture Model Shows Capacity for Proliferation and Differentiation Cellular and Molecular Gastroenterology and Hepatology. | Pubmed ID: 28936470 Although cells comprising esophageal submucosal glands (ESMGs) represent a potential progenitor cell niche, new models are needed to understand their capacity to proliferate and differentiate. By histologic appearance, ESMGs have been associated with both overlying normal squamous epithelium and columnar epithelium. Our aim was to assess ESMG proliferation and differentiation in a 3-dimensional culture model.
MRI Features of Metacarpo(tarso)phalangeal Region Lameness in 40 Horses Veterinary Radiology & Ultrasound : the Official Journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association. Jul-Aug, 2010 | Pubmed ID: 20806872 Lameness originating from the metacarpo(tarso)phalangeal (MP) joint has a significant effect on the use and athletic competitiveness of a horse. The identification of the cause of lameness originating from the MP joint can be challenging, given the limitations of radiography, ultrasonography, and nuclear scintigraphy. Our purpose was to describe the injury types and incidence in magnetic resonance imaging (MRI) studies from 40 horses with lameness attributable to the MP joint region where it was not possible to reach a clinically plausible diagnosis using other imaging modalities. Horses were examined in a 1.5 T magnet (Siemens Medical Solutions) under general anesthesia. The frequency of occurrence of MR lesions was subchondral bone injury (19), straight or oblique distal sesamoidean desmitis (13), articular cartilage injury and osteoarthritis (eight), suspensory branch desmitis (seven), osteochondral fragmentation (seven), proximal sesamoid bone injury (seven), inter-sesamoidean desmitis (four), deep digital flexor tendonitis (four), collateral desmitis (three), superficial digital flexor tendonitis (two), enostosis-like lesions of the proximal phalanx or MCIII (two), desmitis of the palmar annular ligament (one), desmitis of the proximal digital annular ligament (one), and dystrophic calcification of the lateral digital extensor tendon (one). Twenty-five horses had multiple MR abnormalities. MRI provided information that was complementary to radiography, ultrasonography, and nuclear scintigraphy and that allowed for a comprehensive evaluation of all structures in the MP joint region and a diagnosis in all 40 horses.
Cell Lineage Identification and Stem Cell Culture in a Porcine Model for the Study of Intestinal Epithelial Regeneration PloS One. 2013 | Pubmed ID: 23840480 Significant advances in intestinal stem cell biology have been made in murine models; however, anatomical and physiological differences between mice and humans limit mice as a translational model for stem cell based research. The pig has been an effective translational model, and represents a candidate species to study intestinal epithelial stem cell (IESC) driven regeneration. The lack of validated reagents and epithelial culture methods is an obstacle to investigating IESC driven regeneration in a pig model. In this study, antibodies against Epithelial Adhesion Molecule 1 (EpCAM) and Villin marked cells of epithelial origin. Antibodies against Proliferative Cell Nuclear Antigen (PCNA), Minichromosome Maintenance Complex 2 (MCM2), Bromodeoxyuridine (BrdU) and phosphorylated Histone H3 (pH3) distinguished proliferating cells at various stages of the cell cycle. SOX9, localized to the stem/progenitor cells zone, while HOPX was restricted to the +4/'reserve' stem cell zone. Immunostaining also identified major differentiated lineages. Goblet cells were identified by Mucin 2 (MUC2); enteroendocrine cells by Chromogranin A (CGA), Gastrin and Somatostatin; and absorptive enterocytes by carbonic anhydrase II (CAII) and sucrase isomaltase (SIM). Transmission electron microscopy demonstrated morphologic and sub-cellular characteristics of stem cell and differentiated intestinal epithelial cell types. Quantitative PCR gene expression analysis enabled identification of stem/progenitor cells, post mitotic cell lineages, and important growth and differentiation pathways. Additionally, a method for long-term culture of porcine crypts was developed. Biomarker characterization and development of IESC culture in the porcine model represents a foundation for translational studies of IESC-driven regeneration of the intestinal epithelium in physiology and disease.