Sus Scrofa Pig Research Articles

Abstract 9573: Significant Reduction in Ventricular Tachyarrhythmia After Myocardial Infarction in Cardiovascular Progenitors Transplanted Pig Hearts

Stem cell therapy could potentially replace damaged heart muscle for regenerative cardiology. We hypothesized that immature cardiovascular progenitors (CVPs) when transplanted into infarcted hearts would electrically synchronized and mature in vivo thus avoiding the occurrence of VTs. In this study, we reported the derivation and applications of hESC-derived CVPs using highly reproducible (R 2 > 0.95) laminin-221 differentiation protocol. The infarction model was created on 3 months old Sus scrofa pigs where we permanently ligated the coronary arteries and intramyocardially transplanted 200 million CVPs. A total of 3 sham, 10 medium control and 10 CVP transplanted pigs were monitored at 4- and 12-weeks post-transplantation. We demonstrated using 10X spatial transcriptomic analysis at 1-week following transplantation the engraftment of the human CVPs into the pig heart. The cells remained viable and proliferated to formed human graft in the infarcted region at 4- and 12-weeks as indicated by IVIS imaging and histology staining. Heart function was analyzed by magnetic resonance imaging (MRI) and revealed overall improvement in left ventricular ejection fraction by 21.35 ± 3.3 %, which was accompanied by significant improvements in ventricular wall thickness and wall motion, as well as a reduction in infarction size after CVP transplantation as compared to medium control pigs (P < 0.05). Electrophysiology analyses revealed electrical propagation between transplanted cells and host tissue CMs. Temporary episodes of VT over a period of 25 days were developed in 4 out of 10 CVP transplanted pigs and 1 pig had persistent VT, while the rest (n = 5) remained in normal sinus rhythm. All ten pigs survived the experiment without any VT-related death. Finally, computerized tomography (CT) scans revealed no tumor formation after 12-weeks transplantation indicating the long-term safety of the treatment. In conclusion, we reported the generation of an effective and potent CVPs and a significant reduction (50 %) in graft induced VT as compared to studies transplanted with contracting cardiomyocytes. This method may pave the way for stem cell therapy of myocardial infarction in humans.

Keratin-Alginate Sponges Support Healing of Partial-Thickness Burns.

Deep partial-thickness burns damage most of the dermis and can cause severe pain, scarring, and mortality if left untreated. This study serves to evaluate the effectiveness of crosslinked keratin–alginate composite sponges as dermal substitutes for deep partial-thickness burns. Crosslinked keratin–alginate sponges were tested for the ability to support human dermal fibroblasts in vitro and to support the closure and healing of partial-thickness burn wounds in Sus scrofa pigs. Keratin–alginate composite sponges supported the enhanced proliferation of human dermal fibroblasts compared to alginate-only sponges and exhibited decreased contraction in vitro when compared to keratin only sponges. As dermal substitutes in vivo, the sponges supported the expression of keratin 14, alpha-smooth muscle actin, and collagen IV within wound sites, comparable to collagen sponges. Keratin–alginate composite sponges supported the regeneration of basement membranes in the wounds more than in collagen-treated wounds and non-grafted controls, suggesting the subsequent development of pathological scar tissues may be minimized. Results from this study indicate that crosslinked keratin–alginate sponges are suitable alternative dermal substitutes for clinical applications in wound healing and skin regeneration.

Total Pancreatectomy and Pancreatic Allotransplant in a Porcine Experimental Model.

The main objective of this experimental study was to evaluate the feasibility of diabetes induction by total pancreatectomy and pancreatic allotransplant after diabetes induction by total pancreatectomy. The secondary objective was to evaluate metabolic (C-peptide, glycemia) and inflammatory (lactate and platelet levels) parameters after diabetes induction by total pancreatectomy and pancreatic allotransplant after total pancreatectomy. The study protocol was approved by the French Minister of Research (APAFiS no.18169). Insulin-dependent diabetes was induced by total pancreatectomy in one male Sus scrofa pig, and pancreatic allotransplant was performed, after total pancreatectomy, in 3 male Sus scrofa pigs. Total pancreatectomy was performed under general anesthesia,with meticulous dissection of the portal vein and the splenic vein to preserve the spleen. Concerning pancreas procurement, extensive pancreas preparation occurred during thewarm phase,before coldperfusion. Pancreatic allotransplant was performed using donor aorta (with superior mesenteric artery and celiac trunk). Diabetes induction was successful, with negative C-peptide values at 3 hours after total pancreatectomy. Glycemic control without hypoglycemic events was obtained with the use of long-acting insulin administered once per day. No rapid-acting insulin was used. In animals that received pancreatic allotransplant, after enteral feeding was started, glycemic control without hypoglycemic events and without insulin was obtained in 2 animals. In an experimental porcine model, diabetes induction by total pancreatectomy and pancreatic allotransplant after total pancreatectomy are feasible and effective. The development of these models offers the potential for new investigations into ischemia-reperfusion injuries, improvement of pancreas procurement methods, and preservation techniques.

KRASG12D and TP53R167H Cooperate to Induce Pancreatic Ductal Adenocarcinoma in Sus scrofa Pigs

Although survival has improved in recent years, the prognosis of patients with advanced pancreatic ductal adenocarcinoma (PDAC) remains poor. Despite substantial differences in anatomy, physiology, genetics, and metabolism, the overwhelming majority of preclinical testing relies on transgenic mice. Hence, while mice have allowed for tremendous advances in cancer biology, they have been a poor predictor of drug performance/toxicity in the clinic. Given the greater similarity of sus scrofa pigs to humans, we engineered transgenic sus scrofa expressing a LSL-KRASG12D-TP53R167H cassette. By applying Adeno-Cre to pancreatic duct cells in vitro, cells self-immortalized and established tumors in immunocompromised mice. When Adeno-Cre was administered to the main pancreatic duct in vivo, pigs developed extensive PDAC at the injection site hallmarked by excessive proliferation and desmoplastic stroma. This serves as the first large animal model of pancreatic carcinogenesis, and may allow for insight into new avenues of translational research not before possible in rodents.

Anatomical study of the pigs temporal bone by microdissection.

Initial study of the pig`s temporal bone anatomy in order to enable a new experimental model in ear surgery. Dissection of five temporal bones of Sus scrofa pigs obtained from UNIFESP - Surgical Skills Laboratory, removed with hole saw to avoid any injury and stored in formaldehyde 10% for better conservation. The microdissection in all five temporal bone had the following steps: inspection of the outer part, external canal and tympanic membrane microscopy, mastoidectomy, removal of external ear canal and tympanic membrane, inspection of ossicular chain and middle ear. Anatomically it is located at the same position than in humans. Some landmarks usually found in humans are missing. The tympanic membrane of the pig showed to be very similar to the human, separating the external and the middle ear. The middle ear`s appearance is very similar than in humans. The ossicular chain is almost exactly the same, as well as the facial nerve, showing the same relationship with the lateral semicircular canal. The temporal bone of the pigs can be used as an alternative for training in ear surgery, especially due the facility to find it and its similarity with temporal bone of the humans.

Anatomical study of the pigs temporal bone by microdissection

Initial study of the pig`s temporal bone anatomy in order to enable a new experimental model in ear surgery. Dissection of five temporal bones of Sus scrofa pigs obtained from UNIFESP - Surgical Skills Laboratory, removed with hole saw to avoid any injury and stored in formaldehyde 10% for better conservation. The microdissection in all five temporal bone had the following steps: inspection of the outer part, external canal and tympanic membrane microscopy, mastoidectomy, removal of external ear canal and tympanic membrane, inspection of ossicular chain and middle ear. Anatomically it is located at the same position than in humans. Some landmarks usually found in humans are missing. The tympanic membrane of the pig showed to be very similar to the human, separating the external and the middle ear. The middle ear`s appearance is very similar than in humans. The ossicular chain is almost exactly the same, as well as the facial nerve, showing the same relationship with the lateral semicircular canal. The temporal bone of the pigs can be used as an alternative for training in ear surgery, especially due the facility to find it and its similarity with temporal bone of the humans.