TY - JOUR A1 - Strauss, Armin A1 - Moskalenko, Vasily A1 - Tiurbe, Christian A1 - Chodnevskaja, Irina A1 - Timm, Stephan A1 - Wiegering, Verena A. A1 - Germer, Chrioph Thomas A1 - Ulrichs, Karin T1 - Goettingen Minipigs (GMP): Comparison of Two Different Models for Inducing Diabetes N2 - Purpose: Preclinical experiments on large animals are indispensable for evaluating the effectiveness of diabetes therapies. Miniature swine are well suited for such studies due to their physiological and pathophysiological responses. Methods: We compare two methods for inducing diabetes in Goettingen minipigs (GMP), in five with the beta cell toxin streptozotocin (STZ) and in five other GMP by total pancreatectomy (PE). Glucose homeostasis was assessed with the intravenous glucose-tolerance test (IVGTT) and continual monitoring of interstitial glucose levels. At conclusion of the observation period, the pancreata were examined histologically. Three non-diabetic GMP served as control group. Results: The IVGTT revealed markedly diabetic profiles in both GMP groups. STZ-GMP were found to harbor residual C-peptides and scattered insulin-positive cells in the pancreas. PE-GMP survived the total pancreatectomy only with intensive postoperative care. Conclusions: Although both methods reliably induced diabetes in GMP, the PE-GMP clearly had more health problems and required a greater expenditure of time and resources. The PE-GMP model, however, was better at eliminating endogenous insulin and C-peptide than the STZ-GMP model. KW - Göttingen KW - Minischwein KW - diabetes KW - pig or swine KW - real-time glucose monitoring KW - intravenous glucose tolerance test KW - total pancreatectomy KW - streptozotocin Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75119 ER - TY - CHAP A1 - Heiser, A. A1 - Ulrichs, Karin A1 - Müller-Ruchholtz, W. T1 - Enzyme Kinetics of Commercial Collagenases and their Influence on Porcine Islet Isolation N2 - No abstract available KW - Heterotransplantation Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45488 ER - TY - JOUR A1 - Ulrichs, Karin A1 - Bosse, M. A1 - Wacker, HH A1 - Heiser, A. A1 - Müller-Ruchholtz, W. T1 - Histologic analysis of the porcine pancreas to improve islet yield and integrity after collagenase digestion N2 - No abstract available KW - Chirurgie Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45166 ER - TY - JOUR A1 - Ulrichs, Karin A1 - Eckstein, V. A1 - Müller-Buchholtz, W. T1 - Xenogeneic T-cell-mediated immune reactivity in the model of pig-to-humans: first findings with native stimulator cells N2 - No abstract available KW - Chirurgie Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-44755 ER - TY - JOUR A1 - Eckstein, V. A1 - Müller-Buchholtz, W. A1 - Ulrichs, Karin T1 - Reaction patterns of natural xenophile antibodies in human sera with pancreatic islet cells and porcine lymphocytes N2 - No abstract available KW - Chirurgie Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-44742 ER - TY - JOUR A1 - Heiser, Axel A1 - Ulrichs, Karin A1 - Müller-Buchholtz, Wolfgang T1 - Isolation of porcine pancreatic islets: low trypsin activity during the isolation procedure guarantees reproducible high islet yields N2 - During the past few years, interest in xenotransplantation of porcine islets of Langerhans for the future therapy of type I diabetes has Increased markedly. Therefore, we established a semiautomated digestion method for isolating islets from the porcine pancreas. However, although the isolation technique was standardized and collagenase of controlled quality was used, we were unable to attain high islet yields with a satisfactory degree of reproducibility. One hypothesis was that varying degrees of interference by donor pancreatic enzymes were responsible for this failure. The aim of this stUdy was to examine the kinetics of four types of enzymatic activity during the isolation procedure, as well as their effects on islet yield: collagenase, trypsin, neutral protease, and clostripaln. Our results indicate that while exogenous collagenase activity decreases slightly during the isolation procedure, the activity of the pancreas enzymes neutral protease and trypsin increases. In some cases, trypsin activity increases very strongly. A strong increase in trypsin activity correlates with poor islet yield, whereas low trypsin activity always correlates with high islet yield. Addition of the protease inhibitor Pefabloc to the isolation medium results in low trypsin activity and reproducible high islet yields. KW - Langerhans-Inseln KW - islets of Langerhans KW - xenogeneic transplantation KW - swine KW - enzyme activation KW - enzyme inhibitors Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-44719 ER - TY - JOUR A1 - Heiser, A. A1 - Ulrichs, Karin A1 - Müller-Ruchholtz, W. T1 - Prophylactic trypsin inhibition during the isolation procedure guarantees reproducible, high porcine islet yields N2 - Abstract: For isolating islets from the porcine pancreas, we established a semiautomated digestion method. Although the isolation technique was standardized and collagenase of controlled quality was used, until now the reproducibility of high islet yields was unsatisfactory. Our hypothesis was that pancreatic trypsin was responsible for this failure. The aim of this study was to investigate the effect of endogenous trypsin on islet yield. Our results demonstrate that a high trypsin level correlates with poor islet yield, whereas low trypsin activity always correlates with high islet yield. Specific inhibition of trypsin results in low trypsin activity and reproducible, high islet yields. KW - islets of Langerhans KW - xenogenic transplantation KW - swine KW - enzyme activation KW - enzyme inhibitors Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45531 ER - TY - CHAP A1 - Heiser, A. A1 - Ulrichs, Karin A1 - Müller-Ruchholtz, W. T1 - Enzyme Activities in Commercial Collagenase Preparations and Their Kinetics During Islet Isolation Procedure N2 - No abstract available KW - Transplantation Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45633 ER - TY - JOUR A1 - Ulrichs, Karin A1 - Wang, H. A1 - Müller-Buchholtz, W. T1 - Down-regulation of xenophile antibodies by 15-deoxyspergualin in an experimental animal model N2 - No abstract available KW - Chirurgie Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-44733 ER - TY - JOUR A1 - Winoto-Morbach, S. A1 - Krout, OS A1 - Heiser, A. A1 - Ulrichs, Karin A1 - Müller-Ruchholtz, W. T1 - Lectin binding to acinar tissue for complete magnetophoretic purification of porcine pancreatic islets depends on the composition and pH of the incubation medium N2 - No abstract available KW - Chirurgie Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45183 ER -