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Background Renal allograft compartment syndrome (RACS) is an under recognized yet important complication of kidney transplantation that can lead to early graft dysfunction and loss. The use of mesh for prevention and treatment of RACS in very selective circumstances has been documented previously in small case reports. However, it is unknown whether patient and graft survival rates are similar in patients undergoing renal transplantation with mesh placement for the prevention or treatment of RACS. The purpose of our study was to examine the risk factors, indications, and outcomes of mesh hood fascial closure (MHFC) use in the context of RACS prevention. Methods All patients who underwent kidney transplantation in our center between 2009 and 2013 were reviewed. Patients with mesh placed at the time of initial transplantation and secondarily at the time of reoperation were identified. Patient characteristics, Doppler ultrasound findings, and overall patient and graft survival rates were compared among patients with and without mesh placement. Results Of 600 patients who received a kidney transplant, 134 patients underwent mesh placement, 123 primarily and 11 secondarily. Our overall 1-year patient and graft survival rates compared between those with and without MHFC were, respectively, 97.5% and 94.8% compared to 98.5% and 95.5% with P > .05. Our mesh removal rate was 6% (8/134), and the rate of mesh infection was 1.6% (2/134). Conclusions We are the first to report the outcomes of MHFC for the prevention of RACS in patients undergoing renal transplantation. We found that MHFC in select circumstances has minimal risks and similar overall patient and graft survival rates when mesh is not used. Prospective studies to better understand the pathophysiology of RACS will aid in determining objective clinical indications for MHFC to improve allograft survival. [ABSTRACT FROM AUTHOR]

Abstract: Autologous chondrocyte transplantation (ACT) has been established to contribute cartilage regeneration over the past years; however, many obstacles need to be overcome. Recently, newer ACT technique involves cotransplantation of chondrocytes and biomaterial. Although various proposed intelligent biomaterials exist, many of them remain insufficient and controversial. In this study, we aimed to examine the effects of natural extracellular matrix (ECM) to the proliferation rate and differentiation on the chondrocytes. We first derived a natural ECM sheet from 10-μm-thick frozen sections of porcine knee cartilages. We then cultured the chondrocytes derived from a rabbit's knee on a dish precoated with the natural ECM. Then we assessed differentiation and chondrogenic potential of the cells compared with those grown in untreated culture dishes. We characterized the gene expression of chondrogenic markers, such as collagen type II, SOX-9, and aggrecan, as well as the level of ECM protein with the use of reverse-transcription polymerase chain reaction analysis. The cells cultured with the ECM sheet showed highest chondrogenic potential and differentiation. Therefore, we can induce good chondrogenesis by with the use of a natural ECM sheet on the culture dish. The readily available and easy-to-handle thin ECM sheets create an environment that promotes efficient cartilage regeneration. Our data suggest that this natural ECM scaffold improved the chondrogenic differentiation of the cells in vitro by providing a favorable microenvironment. [Copyright &y& Elsevier]

Abstract: Background: Dendritic cells (DCs) are the most powerful antigen-presenting cells in the body. Immature DCs (imDCs) can induce transplantation tolerance. In this study, using a mouse model of skin transplantation. We explored the antigen uptake by imDCs, changes in phenotype and function after antigen loading, as well as survival of skin grafts. Methods: Mononuclear cells from C57BL/6 mice mixed with a tritiated leucine ([3H]Leu) antigen supernate were incubated with Kunming mice imDC and mature DCs. We recorded the expressions of surface molecules that were detected using flow cytometry, mixed lymphocyte reactions, mean survival times, and postoperative morphological changes in skin grafts. Results: After the addition of allogeneic antigen supernate, the counts per minute of imDCs were significantly higher than those of mature DCs. The expression rates of IA/IE and CD80 significantly increased on the cell surface of imDCs. The counts per minute of imDCs in mixed lymphocyte reactions in the presence of allogeneic antigens was significantly higher than those of controls. Comparing mean survival times with controls, skin grafts were significantly longer in the imDCs groups from donors or from a third party carrying donor antigens. Conclusions: ImDCs display a strong antigen uptake, gradually maturing in terms of phenotype and function after loading. Complementary application of cytotoxic T-lymphocyte–associated antigen 4 immunoglobulin blocks the immune response of imDCs. Both imDCs from the third party carrying donor antigens and those from the donor strain can establish antigen-specific immune tolerance to allogeneic skin grafts. [Copyright &y& Elsevier]

Abstract: Background: The importance of drug repositioning has been gaining attention in the last few years, allowing existing pharmaceutical products to be reevaluated for potential alternative therapeutic applications. The purpose of this study was to evaluate the effects of fragmin/protamine microparticles (F/P MPs) on cell aggregates under the concept of drug repositioning. Methods: Mesenchymal stem cells (MSCs) and embryonic rat heart-derived cardiac H9C2 cells were mixed with D-PBS, basal medium, fragmin, protamine, and F/P MPs to manufacture aggregates intended for cell transplantation. To evaluate their adhesive properties as cell carriers, we injected combinations of MSC aggregates into cartilage tissue, observing their leakage from the implantation site. Results: Our data demonstrated that MSCs and H9C2 cells mixed with F/P MPs rapidly produced large, viscous cellular aggregates. F/P MPs were bound to the surface of MSCs and H9C2 cells; thus, F/P MPs induced the formation of F/P MP–cell aggregates. Cell aggregates were prevented from leaking from the transplanted site. Conclusion: Aggregation induced by F/P MPs may improve the efficiency of cell therapy, a novel method for transplantation. [Copyright &y& Elsevier]

Abstract: Objective: The objective of this study was to investigate whether kidney grafts from living related donors older than 50 years were safe for the donors and recipients in the long term. Methods: One hundred seven living related donor kidney transplantations were performed in our center from April 1994 to December 2007. No prisoners or organs from prisoners were used in the collection of these data. Donors were divided into 2 groups: >50 years of age (range, 51–78 years), designated as the study group, and ≤50 years of age (range, 21–50 years), designated as the control groups. The mean time of follow-up was 49 months (range, 12–180 months). Clinical data were compared, including donor serum creatinine (Scr) levels, glomerular filtration rates (GFR) before and after the procedures operative complications, and postoperative short-term and long-term recovery of renal function in recipients as well as their complications and recipient and kidney survivals. Results: All operations were successfully performed. Before the operation, the mean Scr and GFR were 82.16 ± 10.86 umol/L and 85.82 ± 6.26 mL/min, respectively, in the study group versus 78.66 ± 10.41 umol/L and 88.74 ± 9.44 mL/min, respectively, in the control group. There were no significant differences in mean Scr or GFR values between the groups at various preoperative or postoperative times (P > .05). No severe perioperative complications occurred, and no subsequent renal function failure was observed upon long-term follow-up of donors in the 2 groups. Comparisons of recipient age, gender ratio, duration on dialysis, HLA matches, cold/warm ischemia times, and immunosuppression therapy showed a correlations between the 2 groups. Mean Scr levels of recipients, which were compared from 1 week to 3 years following surgery, were slightly higher among the control than the study group, but the difference was not significant (P > .05). There were no significant differences between the study and control groups in 1-,3-,5-, and 8-year recipient/graft survival rates (P > .05). Conclusions: Long-term follow-up showed that transplantations using grafts from donors older than 50 years of age yielded similar results to those with younger donors. [Copyright &y& Elsevier]

Background Polyomavirus BK-associated nephropathy (BKVN) has been a serious problem after kidney transplantation. Detection of urinary decoy cells (UDCs) and assessment of polyomavirus BK nucleic acids by polymerase chain reactions (PCRs) are currently used, noninvasive tests. PCRs have better positive predictive value (PPV) but higher cost and lower accessibility. This study investigated ways to improve the PPV of UDCs for BKVN prediction. Methods From 2000 to 2013, kidney transplant recipients with sustained UDCs for more than half a month and who had received allograft biopsies were enrolled. We analyzed the PPV of UDCs for BKVN with 2 variables: (i) the percentage changes in serum creatinine (SCr) levels and (ii) the duration of sustained UDCs by receiver operating characteristic (ROC) curve analysis; we predicted the percentage changes in SCr levels with the corresponding PPV using a linear regression model. Results BKVN was diagnosed in 26 of 68 enrolled patients. The percentage changes in SCr levels significantly deteriorated in the BKVN group during 1–2 months of UDC positivity. According to ROC curve analysis, percentage changes in SCr levels had a significant discriminating power for BKVN during 1–1.5 month, and if the percentage changes in SCr levels were >19%, the PPV of UDCs for BKVN was 50%. Conclusions An UDC surveillance program is a judicious strategy to predict BKVN in kidney transplant patients, particularly when graft renal function shows deterioration after 1 month of UDC positivity. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases associated with myocardial infarction are among the major causes of death worldwide due to the limited regenerative capacity of cardiac tissues. Although various approaches, such as biosynthetic biomaterials, have been developed to promote postinfarction cardiac regeneration, a number of limitations, including the immune complications caused by biodegradation of these scaffolds and insufficient cell migration, need to be overcome prior to their clinical application. Hence, the development of natural biomaterials to support myocardial regeneration is crucial. Here, we investigated the effects of a natural biomaterial, cardiac extracellular matrix (ECM) on the proliferation and maintenance of cardiomyocytes in order to assess its suitability for cardiomyocyte expansion. The ECM components not only provide mechanical support, but also induce and preserve the required phenotypic and functional characteristics of the cells. We prepared ECM sheets from decellularized cardiac sections. Cardiomyocytes were then cultured with and without these cardiac ECM sheets. We compared the proliferation rates and phenotypes, and cardiac gene and protein expression, of the cultured cardiomyocytes by automatic cell counting and the MTT assay, microscopy, and RT-PCR and western blotting, respectively. The cardiomyocytes cultured with the natural cardiac ECM sheets exhibited higher proliferation rates and cardiac gene and protein expression than those cultured without the ECM sheets. Our results demonstrate that the ECM sheets are suitable for use in cardiomyocyte transplantation and can provide a novel in vitro model for investigating cell and ECM interactions. We hypothesize that these ECM sheets can be used in the future to improve cardiac transplantation strategies. [ABSTRACT FROM AUTHOR]

Pancreatic islets have been the focus of recent studies exploring the pathologic mechanisms of diabetes mellitus as well as more effective and radical treatments for this disease. Islet transplantation is a promising therapeutic strategy; however, isolation of pancreatic islets for this purpose has been challenging, because the technique is time consuming and technically difficult, and tissue handling can be variable. Pseudo-islets can be used as an alternative to naïve islets, but require cellular sources or artificial materials. In this study, pancreas-derived cells were used to generate pseudo-islets. Because the pancreas is composed of a variety of cell types, namely α cells, β cells, δ cells, and other pancreatic cells that perform different functions, we used 3 different cell lines—NIT-1 (a β-cell line), α TC1 clone 6 (an α-cell line), and TGP52 (a pancreatic epithelial-like cell line)—which we cocultured in nonadhesive culture plates to produce hybrid cellular spheroids. These pseudo-islets had an oval shape and were morphologically similar to naïve islets; additionally, they expressed and secreted the pancreatic hormones insulin, glucagon, and somatostatin, as confirmed by reverse-transcription polymerase chain reaction and enzyme-linked immunosorbent assay. The results demonstrate that pseudo-islets that mimic naïve islets can be successfully generated by a coculture method. These artificial islets can potentially be used for in vitro tests related to diabetes mellitus, specifically, in drug discovery or for investigating pathology. Moreover, they can be useful for examining basic questions pertaining to cell-cell interactions and tissue development. [ABSTRACT FROM AUTHOR]

Abstract: Autologous chondrocyte transplantation (ACT) is an effective and safe therapy for repairing articular cartilage defects and requires cell preservation and subculture before transplantation. We compared the effects of cryopreservation and passaging on cell viability, proliferation, and maintenance of the function of chondrocytes and synovium-derived mesenchymal stem cells (MSCs) used as sources for ACT. These cells were isolated from the knee joints of rabbits and were cultured, passaged serially, and divided into 2 groups that were either cryopreserved or not. The morphology, viability, gene expression, and differentiation potential of the 2 groups were compared. Maintenance of the potential to undergo chondrogenic differentiation was determined with the use of a 3-dimensional culture method. Passaging and cryopreservation significantly affected the ability of chondrocytes to maintain their morphology, express chondrogenic genes, and differentiate. In contrast, synovium-derived cells were not affected by passaging and cryopreservation. Our results may serve as the foundation for the application of passaged and cryopreserved chondrocyte or other source cells of MSCs in ACT. [Copyright &y& Elsevier]

Autologous chondrocyte transplantation involves isolating chondrocytes from a patient's cartilage tissue. Storage conditions such as storage time and temperature are important for the quality of the isolated cells. However, few studies have focused on variables for optimum tissue preservation, and there is neither an established method for storing cartilage nor reliable reports on how different conditions affect the isolated chondrocytes. Therefore, in the present study, we stored cartilage in various preservation solutions, under different temperatures, and for varying durations and determined their effects on the characteristics and viability of isolated chondrocytes. We assessed chondrocyte viability with the use of a cell proliferation assay and determined their chondrogenic potential with the use of reverse-transcription polymerase chain reaction, enzyme-linked immunosorbent assay, and glycosaminoglycan assays. Our results demonstrated that cartilage tissue stored in a preservation medium composed of dimethyl sulfoxide, fetal bovine serum, and Dulbecco Modified Eagle Medium at a ratio of 1:2:7 (v/v) or stored with a commercially available preservation solution generated greater numbers of chondrocytes when the storage temperature was −80°C than when it was 4°C. The viability of isolated cells decreased with time at 4°C, whereas these values remained constant for tissues stored at −80°C. Our data suggest that an optimal method for preserving cartilage tissue is required to ensure the quality of cells used for transplantation. [ABSTRACT FROM AUTHOR]

Abstract: Mesenchymal stem cells (MSCs) are multipotent stromal elements that can differentiate into a variety of cell types. MSCs are good sources of therapeutic cells for degenerative diseases. For these reason, many researchers have focused on searching for other sources of MSCs. To obtain MSCs for clinical use requires surgery of the donor that therefore can induce donor morbidity, since the common sources at present are bone marrow and adipose tissues. In this study, we investigated the existence of MSCs in postoperative discarded tissues. Subacromial bursal tissues were obtained from the shoulders of 3 injured patients. The cells from the bursa tissues were isolated through treatment with collagenase. The isolated cells were then seeded and expanded by serial passaging under normal culture system. To evaluate MSC characteristics of the cells, their MSC markers were confirmed by mRNA and protein expression. Multipotent ability was assessed using differentiation media and immunohistochemistry. Cells from the bursa expressed MSCs markers—CD29, CD73, CD90, and PDGFRB (platelet-derived growth factor receptor-beta). Moreover, as to their multipotency, bursal cells differentiated into adipocytes (fat cells), osteocytes (bone cells), and chondrocytes (cartilage cells). In summary, we showed that MSCs could be generated from the subacromial bursa, which is medical waste after surgery. [Copyright &y& Elsevier]

Abstract: Investigators conducting diabetes-related research have focused on islet transplantation as a radical therapy for type 1 diabetes mellitus. Pancreatic islet isolation, an essential process, is a very demanding work because of the proteolytic enzymes, species, treatment time, and individual difference. Replacement of primary isolated pancreatic islets must be carried out continuously for various in vitro tests, making primary isolated islets a useful tool for cell transplantation research. Hence, we sought to develop pseudoislets from commercial pancreas-derived cell lines. In this study, we used RIN-5F and RIN-m cells, which secrete insulin, somatostatin, or glucagon. To manufacture hybrid cellular spheroids, the cells were cultured under hanging drop plate and nonadhesive plate methods. We observed that hybrid cellular pseudoislets exhibited an oval shape, with sizes ranging from 590 to 1200 μm. Their morphology was similar to naïve islets. Cell line pseudoislets secreted and expressed insulin, glucagon, and somatostatin, as confirmed by reverse transcriptase polymerase chain reaction, enzyme-linked immunosorbent assay, and immunohistochemistry analyses. Thus, the current artificially manufactured biomimetic pseudoislets resembled pancreatic islets of the endocrine system, appearing as cellular aggregates that secreted insulin, glucagon, and somatostatin. Enhanced immunoisolation techniques may lead to the development of new islet sources for pancreatic transplantation through this pseudoislet strategy. [Copyright &y& Elsevier]

Abstract: Background: Before cell or tissue transplantation, cells or tissues have to be maintained for a certain period in vitro using culture medium and methods. Most culture media contain substances such as pH indicators and buffers. It is not known whether some of these substances are safe for subsequent application in the transplantation of cells or tissues into the human body. We investigated culture media and methods with respect to the safety of the components in future transplantation applications. Methods: A modified culture medium—medical fluid-based culture medium (FCM)—was designed by using various fluids and injectable drugs that are already currently permitted for use in clinical medicine. Medium components necessary for optimal cell growth were obtained from approved drugs. FCM was manufactured with adjusted final concentrations of the medium components similar to those in commercial Dulbecco's modified Eagle's medium (DMEM). In particular, 1029.40 mg/L amino acids, approximately 88.85 mg/L vitamins, 13,525.77 mg/L inorganic salts, and 4500 mg/L D-glucose comprise the high-glucose FCM. Next, human fat synovium-derived mesenchymal stem cells and rat H9c2 (2-1) cells were cultured under 2 conditions: (1) DMEM-high glucose (HG), an original commercial medium, and (2) optimized FCM-HG. We assessed the morphologies and proliferation rates of these cells. Results: We observed that FCM-HG was able to induce the growth of FS-MSC and commercially available H9c2 cell. The morphologies and proliferation patterns of these cells cultured under FCM-HG showed no differences compared with cells grown in DMEM-HG. Conclusion: Our data suggest that FCM, which we developed for the first time according to the concept of drug repositioning, was a useful culture medium, especially in cultured cells intended for human cell transplantation. [Copyright &y& Elsevier]

Abstract: Objective: To establish an acute rejection model after kidney transplantation in the rat using a modified method of ureterovesical anastomosis. Methods: Thirty-nine Wistar rat donors, were transplanted into 70 male SD rats. Wistar rats (group 1; n = 18) underwent harvest of both kidneys, cold perfusion, and transplantation into 36 SD rats. Wistar rats (group 2; n = 18) underwent left kidney harvest, cold perfusion and transplantation into 18 SD rats. Groups 1 and 2 did not receive immunosuppression after transplantation. Six kidneys were harvested from 3 Wistar rats (group 3), were transplanted into 6 SD rats that were treated with CsA (5 mg/kg per day) postoperatively, and humanely killed at 21 days. There were 10 SD in sham operated rats (group 4). The renal allograft vein was end-to-end anastomosed to the recipient renal vein using an epidural catheter. The renal allograft was anastomosed end-to-side to the recipient abdominal aorta with an abdominal aortic flap. The renal allograft ureterovesical flap was directly inserted into the recipient bladder, and attached by 4–5 interrupted sutures. The recipient''s right kidney vessels were ligated at 3 days postoperatively. Results: The success rates were 91.7% and 88.9% in groups 1 and 2, respectively. Except for the time for removal of the renal allografts, the operative durations and warm ischemia times differed insignificantly between both groups (P > .05). Blood creatinine levels increased significantly after kidney transplantation in groups 1 and 2 compared with the sham operated and CsA-treated cohorts (P < .01), but insignificantly between groups 1 and 2 (P > .05). Conclusions: A dual renal allograft model was established in the rat using a modified ureterovesical anastomosis. The technique can be reproduced reliably, reducing costs and shorten using overall operative duration. [Copyright &y& Elsevier]