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Renal Capsule (renal + capsule)
Selected AbstractsLymphatic Vessels in Pancreatic Islets Implanted Under the Renal Capsule of RatsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2006Ö. Källskog Transplantation of pancreatic islets necessitates an engraftment process, including revascularization of the graft. Studies of graft vasculature have demonstrated that islets become revascularized during the first post-transplant week through an angiogenic process. If this also involves lymphatic vessels is unknown. The aim of the present study was to functionally evaluate if lymphatic vessels, which are absent in endogenous islets, form after islet transplantation. To achieve this, inbred Wistar-Furth rats were transplanted with 250 syngeneic islets under the renal capsule. Intra-vital microscopy of the graft in combination with interstitial injection of Evans Blue was performed 1 week, 1 month or 9,12 months later. In all animals studied, there was drainage through intra-graft lymphatic capillaries emptying into larger lymphatic vessels associated with the renal capsule. The number was slightly lower 1 week post-transplantation. Most of the lymphatic capillaries were present in the graft stroma, rather than interspersed among the endocrine cells. In some animals, we were able to demonstrate dye in regional lymph nodes. We conclude that unlike endogenous islets, islet grafts develop a lymphatic drainage. Its functional importance and characteristics remain to be established. However, it can be speculated that immune reactions may be facilitated by the presence of lymphatic vessels. [source] Local regulation of human breast xenograft models,,JOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2010Jodie M. Fleming Breast cancer studies implant human cancer cells under the renal capsule, subcutaneously, or orthotopically and often use estrogen supplementation and immune suppressants (etoposide) in xenograft mouse models. However, cell behavior is significantly impacted by signals from the local microenvironment. Therefore, we investigated how the combinatorial effect of the location of injection and procedural differences affected xenograft characteristics. Patient-derived breast cancer cells were injected into mouse abdominal or thoracic mammary glands,±,estrogen and/or etoposide pretreatment. Abdominal xenografts had increased tumor incidence and volume, and decreased latency (P,<,0.001) compared to thoracic tumors. No statistically significant difference in tumor volume was found in abdominal xenografts treated,±,estrogen or etoposide; however, etoposide suppressed tumor volume in thoracic xenografts (P,<,0.02). The combination of estrogen and etoposide significantly decreased tumor incidence in both sites. In addition, mice treated,±,estradiol were injected orthotopically or subcutaneously with well-characterized breast cancer cell lines (MCF7, ZR75-1, MDA MB-231, or MCF10Ca1h). Orthotopic injection increased tumor volume; growth varied with estrogen supplementation. Location also altered methylation status of several breast cancer-related gene promoters. Lastly, vascularization of orthotopic tumors was significantly enhanced compared to subcutaneous tumors. These data suggest that optimal xenograft success occurs with orthotopic abdominal injections and illustrate molecular details of the compelling influence of the local microenvironment on in vivo models. J. Cell. Physiol. 224: 795,806, 2010. Published 2010 Wiley-Liss, Inc. [source] Induction of Indoleamine 2,3-Dioxygenase by Gene Delivery in Allogeneic Islets Prolongs Allograft SurvivalAMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2010H. Dellê Indoleamine 2,3-dioxygenase (IDO), an enzyme that plays a critical role in fetomaternal tolerance, exerts immunoregulatory functions suppressing T-cell responses. The aims of this study were to promote IDO expression in rat islets using a nonviral gene transfer approach, and to analyze the effect of the in vivo induction of IDO in a model of allogeneic islet transplantation. The IDO cDNA was isolated from rat placenta, subcloned into a plasmid and transfected into rat islets using Lipofectamine. The efficiency of transfection was confirmed by qRT-PCR and functional analysis. The in vivo effect of IDO expression was analyzed in streptozotocin-induced diabetic Lewis rats transplanted with allogeneic islets under the renal capsule. Transplantation of IDO-allogeneic islets reversed diabetes and maintained metabolic control, in contrast to transplantation of allogeneic nontransfected islets, which failed shortly after transplantation in all animals. Graft survival of allograft islets transfected with IDO transplanted without any immunosuppression was superior to that observed in diabetic rats receiving nontransfected islets. These data demonstrated that IDO expression induced in islets by lipofection improved metabolic control of streptozotocin-diabetic rats and prolonged allograft survival. [source] Lymphatic Vessels in Pancreatic Islets Implanted Under the Renal Capsule of RatsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2006Ö. Källskog Transplantation of pancreatic islets necessitates an engraftment process, including revascularization of the graft. Studies of graft vasculature have demonstrated that islets become revascularized during the first post-transplant week through an angiogenic process. If this also involves lymphatic vessels is unknown. The aim of the present study was to functionally evaluate if lymphatic vessels, which are absent in endogenous islets, form after islet transplantation. To achieve this, inbred Wistar-Furth rats were transplanted with 250 syngeneic islets under the renal capsule. Intra-vital microscopy of the graft in combination with interstitial injection of Evans Blue was performed 1 week, 1 month or 9,12 months later. In all animals studied, there was drainage through intra-graft lymphatic capillaries emptying into larger lymphatic vessels associated with the renal capsule. The number was slightly lower 1 week post-transplantation. Most of the lymphatic capillaries were present in the graft stroma, rather than interspersed among the endocrine cells. In some animals, we were able to demonstrate dye in regional lymph nodes. We conclude that unlike endogenous islets, islet grafts develop a lymphatic drainage. Its functional importance and characteristics remain to be established. However, it can be speculated that immune reactions may be facilitated by the presence of lymphatic vessels. [source] The Development of the Metanephric Kidney in the PigANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005H. Bragulla Aims:, The metanephric kidneys of the pig are used as xenotransplants in human medicine. In order for transplants to fit within the host organisms, the subcapsular blastema and blood vessels are crucial for the development of new nephrons to sustain the organ functions. The aim of this study is to obtain data concerning the post-natal development of metanephric nephrons in the porcine kidney. Materials and Methods:, The metanephric kidneys of six porcine fetuses with a crown-rump length ranging from 40 mm to 220 mm of eight piglets aged between 6 to 10 weeks and of three adult pigs were studied. Eight lectins as well as anti-actin and anti-myosin antibodies were used for lectin- and immunohistochemistry to study the subcapsular metanephric blastema, to visualize the blood-urine barrier in the nephrons and collecting tubules, and to study the blood vessels in both the renal cortex and marrow. Results and Conclusions:, A subcapsular metanephric blastema was still present in the kidney of 10-week-old piglets. Dense condensation of mesenchymal cells surrounded the terminal branches of the collecting ducts and showed first signs of mesenchymal-epithelial transformation. Characteristic comma-shaped and s-shaped bodies were found in and underneath the subcapsular blastema. In the fibrous renal capsule of six-week-old piglets, a first faint binding reaction of anti-actin was visible and intensified in the fibrous renal capsule in ten-week-old piglets and in adult pigs. In addition, the smooth-muscle layers of the blood vessels were stained by the anti-actin and anti-myosin antibodies. The lectins showed various affinities to the endothelium of blood vessels and to the epithelial cells lining of the capsules of the metanephric renal corpuscles, the various parts of the renal tubules, as well as the collecting tubules and the renal pelvis. The affinity of the epithelial cells to a specific lectin varies in neighbouring cells, indicating different cell activities or cell cycles. [source] Case Report: Fatal Apophysomyces elegans Infection Transmitted by Deceased Donor Renal AllograftsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2010B. D. Alexander Two patients developed renal mucormycosis following transplantation of kidneys from the same donor, a near-drowning victim in a motor vehicle crash. Genotypically, indistinguishable strains of Apophysomyces elegans were recovered from both recipients. We investigated the source of the infection including review of medical records, environmental sampling at possible locations of contamination and query for additional cases at other centers. Histopathology of the explanted kidneys revealed extensive vascular invasion by aseptate, fungal hyphae with relative sparing of the renal capsules suggesting a vascular route of contamination. Disseminated infection in the donor could not be definitively established. A. elegans was not recovered from the same lots of reagents used for organ recovery or environmental samples and no other organ transplant-related cases were identified. This investigation suggests either isolated contamination of the organs during recovery or undiagnosed disseminated donor infection following a near-drowning event. Although no changes to current organ recovery or transplant procedures are recommended, public health officials and transplant physicians should consider the possibility of mucormycosis transmitted via organs in the future, particularly for near-drowning events. Attention to aseptic technique during organ recovery and processing is re-emphasized. [source] | ||||||||||