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Sample records for cell sheet allografts

  1. Cell sheet engineering

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    Masayuki Yamato

    2004-05-01

    Full Text Available We have developed ‘cell sheet engineering’ in order to avoid the limitations of tissue reconstruction using biodegradable scaffolds or single cell suspension injection. Our concept is tissue reconstruction, not from single cells, but from cell sheets. Cell sheets are prepared using temperature-responsive culture dishes. Temperature-responsive polymers are covalently grafted onto the dishes, allowing various types of cells to adhere and proliferate at 37°C. The cells spontaneously detach when the temperature is reduced below 32°C without the need for proteolytic enzymes. The confluent cells are noninvasively harvested as single, contiguous cell sheets with intact cell-cell junctions and deposited extracellular matrix (ECM. We have used these harvested cell sheets for various tissue reconstructions, including ocular surfaces, periodontal ligaments, cardiac patches, and bladder augmentation.

  2. The role of CD8+ T cells during allograft rejection

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    Bueno V.

    2002-01-01

    Full Text Available Organ transplantation can be considered as replacement therapy for patients with end-stage organ failure. The percent of one-year allograft survival has increased due, among other factors, to a better understanding of the rejection process and new immunosuppressive drugs. Immunosuppressive therapy used in transplantation prevents activation and proliferation of alloreactive T lymphocytes, although not fully preventing chronic rejection. Recognition by recipient T cells of alloantigens expressed by donor tissues initiates immune destruction of allogeneic transplants. However, there is controversy concerning the relative contribution of CD4+ and CD8+ T cells to allograft rejection. Some animal models indicate that there is an absolute requirement for CD4+ T cells in allogeneic rejection, whereas in others CD4-depleted mice reject certain types of allografts. Moreover, there is evidence that CD8+ T cells are more resistant to immunotherapy and tolerance induction protocols. An intense focal infiltration of mainly CD8+CTLA4+ T lymphocytes during kidney rejection has been described in patients. This suggests that CD8+ T cells could escape from immunosuppression and participate in the rejection process. Our group is primarily interested in the immune mechanisms involved in allograft rejection. Thus, we believe that a better understanding of the role of CD8+ T cells in allograft rejection could indicate new targets for immunotherapy in transplantation. Therefore, the objective of the present review was to focus on the role of the CD8+ T cell population in the rejection of allogeneic tissue.

  3. Veto cell suppression mechanisms in the prevention of allograft rejection

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    Jacobsen, I M; Claesson, Mogens Helweg

    1998-01-01

    tolerizing effect of pretransplant donor blood transfusions in kidney graft recipients. A prerequisite for a veto-active environment in vivo is the establishment of lymphoid microchimerism, in which veto-active donor and recipient cells mutually downregulate potential alloaggression.......Substantial evidence has accumulated to suggest that in the near future implementation of the veto-cell-suppressor concept in the treatment of kidney allograft recipients might lead to the establishment of life-long specific allograft tolerance in the absence of further immunosuppressive therapy...... on the surface of the veto-active cell. Data from a large number of experimental and clinical studies strongly indicate that veto-active cells function in vivo and are capable of preventing allograft rejection. Thus, donor-cell-mediated veto activity is the most likely explanation for the well-known graft...

  4. Immune reactivity of cells from long-term rat renal allograft survivors

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    Weiss, A.; Stuart, F.P.; Fitch, F.W.

    1978-11-01

    Lewis rats receiving an LBN kidney allograft demonstrate no signs of rejection if they are pretreated with donor spleen cells and antiserum reactive with the donor alloantigen. We examined the cellular reactivity of long-term kidney allograft survivors. Normal proliferative and cytolytic responses were obtained with spleen cells from long-term survivors, in marked contrast to the diminished responses of cells from neonatally tolerant rats or the heightened cytolytic response of cells from rats that had rejected a renal allograft. Serum from long-term renal allograft survivors as well as serum obtained from rats at the time of transplantation did not suppress proliferative or cytolytic responses of normal cells. The results of this study suggest that long-term renal allograft survivors possess the precursors of those cells which are responsible for proliferative and cytolytic responses in mixed leukocyte cultures, but that they have not been sensitized to their renal allograft.

  5. Stem cell autograft and allograft in autoimmune diseases.

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    De Cata, Angelo; Matarangolo, Angela; Inglese, Michele; Rubino, Rosa; Mazzoccoli, Gianluigi

    2016-02-01

    Autoimmune diseases are characterized by an insufficiency of immune tolerance and, although treated with a number of useful drugs, may need more unconventional therapeutic strategies for their more severe presentations. Among such unconventional therapeutic approaches, stem cell autograft and allograft have been used, with the aim of stimulating disease remission by modifying the pathogenic mechanisms that induce anomalous responses against self-antigens. Autologous transplantation is performed with the purpose of retuning autoimmune cells, whereas allogeneic transplantation is performed with the purpose of replacing anomalous immune effectors and mediators. In this article, we comprehensively review up-to-date information on the autoimmune diseases for which the transplantation of stem cells is indicated.

  6. Cytological features of live limbal tissue donor eyes for autograft or allograft limbal stem cell transplantation

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    Jeison de Nadai Barros

    2011-08-01

    Full Text Available PURPOSE: To evaluate by impression cytology (IC the corneal surface of live limbal tissue donor eyes for autograft or allograft limbal stem cell transplantation (LSCT. METHODS: Twenty limbal donors were enrolled (17 for autograft LSCT and 3 for allograft. Impression cytology was performed before transplantation of superior and inferior limbal grafts and after the third postoperative month. RESULTS: Impression cytology analysis showed sheets of corneal epithelial cells and goblet cell absence beyond the edge of the keratectomy sites in all patients, suggesting that conjunctival invasion towards the center did not occur in any eye. Partial conjunctivalization within 2 to 3 clock hours, confirmed by the presence of goblet cells, was limited to the keratectomy site in 10% of the cases. CONCLUSION: A clear central corneal surface was demonstrated in all eyes following surgery leading to the conclusion that limbal donation was a safe procedure in this group of patients. A small percentage of eyes can have donor sites re-epithelized with conjunctival cells at the periphery of the cornea.

  7. B cells assist allograft rejection in the deficiency of protein kinase c-theta.

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    Yan, Wenwei; Xu, Rui; Ma, Lian Li; Han, Wei; Geevarghese, Sunil K; Williams, Phillip E; Sciammas, Roger; Chong, Anita S; Yin, Deng Ping

    2013-09-01

    We have previously shown that mice deficient in protein kinase C theta (PKCθ) have the ability to reject cardiac allografts, but are susceptible to tolerance induction. Here we tested role of B cells in assisting alloimmune responses in the absence of PKCθ. Mouse cardiac allograft transplantations were performed from Balb/c (H-2d) to PKCθ knockout (PKCθ(-/-)), PKCθ and B cell double-knockout (PBDK, H-2b) mice and wild-type (WT) C57BL/6 (H-2b) mice. PBDK mice spontaneously accepted the allografts with the inhibition of NF-κB activation in the donor cardiac allograft. Anti-B cell antibody (rituximab) significantly delayed allograft rejection in PKCθ(-/-), but not in WT mice. Co-transfer of PKCθ(-/-) T plus PKCθ(-/-) B cells or primed sera triggered allograft rejection in Rag1(-/-) mice, and only major histocompatibility complex class II-enriched B cells, but not class I-enriched B cells, were able to promote rejection. This, together with the inability of PKCθ(-/-) and CD28(-/-) double-deficient (PCDK) mice to acutely reject allografts, suggested that an effective cognate interaction between PKCθ(-/-) T and B cells for acute rejection is CD28 molecule dependent. We conclude that T-B cell interactions synergize with PKCθ(-/-) T cells to mediate acute allograft rejection.

  8. Host-based Th2 cell therapy for prolongation of cardiac allograft viability.

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    Shoba Amarnath

    Full Text Available Donor T cell transfusion, which is a long-standing approach to prevent allograft rejection, operates indirectly by alteration of host T cell immunity. We therefore hypothesized that adoptive transfer of immune regulatory host Th2 cells would represent a novel intervention to enhance cardiac allograft survival. Using a well-described rat cardiac transplant model, we first developed a method for ex vivo manufacture of rat host-type Th2 cells in rapamycin, with subsequent injection of such Th2.R cells prior to class I and class II disparate cardiac allografting. Second, we determined whether Th2.R cell transfer polarized host immunity towards a Th2 phenotype. And third, we evaluated whether Th2.R cell therapy prolonged allograft viability when used alone or in combination with a short-course of cyclosporine (CSA therapy. We found that host-type Th2.R cell therapy prior to cardiac allografting: (1 reduced the frequency of activated T cells in secondary lymphoid organs; (2 shifted post-transplant cytokines towards a Th2 phenotype; and (3 prolonged allograft viability when used in combination with short-course CSA therapy. These results provide further support for the rationale to use "direct" host T cell therapy for prolongation of allograft viability as an alternative to "indirect" therapy mediated by donor T cell infusion.

  9. Gr-1intCD11b+ myeloid-derived suppressor cells accumulate in corneal allograft and improve corneal allograft survival.

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    Choi, Wungrak; Ji, Yong Woo; Ham, Hwa-Yong; Yeo, Areum; Noh, Hyemi; Jin, Su-Eon; Song, Jong Suk; Kim, Hyeon Chang; Kim, Eung Kwon; Lee, Hyung Keun

    2016-12-01

    We identified the characteristics of myeloid-derived suppressor cells (MDSCs) and investigated their mechanism of induction and their functional role in allograft rejection using a murine corneal allograft model. In mice, MDSCs coexpress CD11b and myeloid differentiation antigen Gr-1. Gr-1(+)CD11b(+) cells infiltrated allografted corneas between 4 d and 4 wk after surgery; however, the frequencies of Gr-1(+)CD11b(+) cells were not different between accepted and rejected allografts or in peripheral blood or BM. Of interest, Gr-1(int)CD11b(+) cells, but not Gr-1(hi)CD11b(+) cells, infiltrated the accepted graft early after surgery and expressed high levels of immunosuppressive cytokines, including IL-10, TGF-β, and TNF-related apoptosis-inducing ligand. This population remained until 4 wk after surgery. In vitro, only high dose (>100 ng/ml) of IFN-γ plus GM-CSF could induce immunosuppressive cytokine expression in Gr-1(int)CD11b(+) cells. Furthermore, adoptive transfer of Gr-1(int)CD11b(+) cells reduced T cell infiltration, which improved graft survival. In conclusion, high-dose IFN-γ in allograft areas is essential for development of Gr-1(int)CD11b(+) MDSCs in corneal allografts, and subtle environmental changes in the early period of the allograft can result in a large difference in graft survival.

  10. Laminins affect T cell trafficking and allograft fate.

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    Warren, Kristi J; Iwami, Daiki; Harris, Donald G; Bromberg, Jonathan S; Burrell, Bryna E

    2014-05-01

    Lymph nodes (LNs) are integral sites for the generation of immune tolerance, migration of CD4⁺ T cells, and induction of Tregs. Despite the importance of LNs in regulation of inflammatory responses, the LN-specific factors that regulate T cell migration and the precise LN structural domains in which differentiation occurs remain undefined. Using intravital and fluorescent microscopy, we found that alloreactive T cells traffic distinctly into the tolerant LN and colocalize in exclusive regions with alloantigen-presenting cells, a process required for Treg induction. Extracellular matrix proteins, including those of the laminin family, formed regions within the LN that were permissive for colocalization of alloantigen-presenting cells, alloreactive T cells, and Tregs. We identified unique expression patterns of laminin proteins in high endothelial venule basement membranes and the cortical ridge that correlated with alloantigen-specific immunity or immune tolerance. The ratio of laminin α4 to laminin α5 was greater in domains within tolerant LNs, compared with immune LNs, and blocking laminin α4 function or inducing laminin α5 overexpression disrupted T cell and DC localization and transmigration through tolerant LNs. Furthermore, reducing α4 laminin circumvented tolerance induction and induced cardiac allograft inflammation and rejection in murine models. This work identifies laminins as potential targets for immune modulation.

  11. The Origin of Neointimal Smooth Muscle Cells in Transplant Arteriosclerosis from Recipient Bone-marrow Cells in Rat Aortic Allograft

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    SONG Zifang; LI Wei; ZHENG Qichang; SHANG Dan; SHU Xiaogang; GUAN Siming

    2007-01-01

    In order to investigate the origin of neointimal smooth muscle cells in transplant arteriosclerosis in rat aortic allograft, sex-mismatched bone marrow transplantation was performed from male Wistar rats to female Wistar rats. Four weeks after transplantation, the aortic transplant model was established by means of micro-surgery in rats. The recipients were divided into 4 groups: female Wistar-female Wistar aortic isografts, female SD-female Wistar aortic allografts, male SD-male Wistar aortic allografts, female SD-chimera Wistar aortic allografts. Eight weeks after transplantation, aortic grafts were removed at autopsy and processed for histological evaluation and immunohistochemistry. The results indicated that excessive accumulation of α-SMA-positive smooth muscle cells resulted in significant neointima formation and vascular lumen stricture in rat aortic allografts.Neointima assay revealed that the neointimal area and NIA/MA ratio of transplanted artery were significantly increased in all of aortic allograft groups as compared with those in aortic isograft group (P<0.01). Neointimal smooth muscle cells were harvested from cryostat sections of aortic allograft by microdissection method. The Sry gene-specific PCR was performed, and the result showed that a distinct DNA band of 225 bp emerged in the male-male aortic allograft group and chimera aortic allograft group respectively, but not in the female-female aortic allograft group. It was suggested that recipient bone-marrow cells, as the origin of neointimal smooth muscle cells, contributed to the pathological neointimal hyperplasia of aortic allograft and transplant arteriosclerosis.

  12. Dendritic Cells in Kidney Transplant Biopsy Samples Are Associated with T Cell Infiltration and Poor Allograft Survival.

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    Batal, Ibrahim; De Serres, Sacha A; Safa, Kassem; Bijol, Vanesa; Ueno, Takuya; Onozato, Maristela L; Iafrate, A John; Herter, Jan M; Lichtman, Andrew H; Mayadas, Tanya N; Guleria, Indira; Rennke, Helmut G; Najafian, Nader; Chandraker, Anil

    2015-12-01

    Progress in long-term renal allograft survival continues to lag behind the progress in short-term transplant outcomes. Dendritic cells are the most efficient antigen-presenting cells, but surprisingly little attention has been paid to their presence in transplanted kidneys. We used dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin as a marker of dendritic cells in 105 allograft biopsy samples from 105 kidney transplant recipients. High dendritic cell density was associated with poor allograft survival independent of clinical variables. Moreover, high dendritic cell density correlated with greater T cell proliferation and poor outcomes in patients with high total inflammation scores, including inflammation in areas of tubular atrophy. We then explored the association between dendritic cells and histologic variables associated with poor prognosis. Multivariate analysis revealed an independent association between the densities of dendritic cells and T cells. In biopsy samples with high dendritic cell density, electron microscopy showed direct physical contact between infiltrating lymphocytes and cells that have the ultrastructural morphologic characteristics of dendritic cells. The origin of graft dendritic cells was sought in nine sex-mismatched recipients using XY fluorescence in situ hybridization. Whereas donor dendritic cells predominated initially, the majority of dendritic cells in late allograft biopsy samples were of recipient origin. Our data highlight the prognostic value of dendritic cell density in allograft biopsy samples, suggest a new role for these cells in shaping graft inflammation, and provide a rationale for targeting dendritic cell recruitment to promote long-term allograft survival.

  13. Hair Follicle Dermal Sheath Derived Cells Improve Islet Allograft Survival without Systemic Immunosuppression

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    Xiaojie Wang

    2015-01-01

    Full Text Available Immunosuppressive drugs successfully prevent rejection of islet allografts in the treatment of type I diabetes. However, the drugs also suppress systemic immunity increasing the risk of opportunistic infection and cancer development in allograft recipients. In this study, we investigated a new treatment for autoimmune diabetes using naturally immune privileged, hair follicle derived, autologous cells to provide localized immune protection of islet allotransplants. Islets from Balb/c mouse donors were cotransplanted with syngeneic hair follicle dermal sheath cup cells (DSCC, group 1 or fibroblasts (FB, group 2 under the kidney capsule of immune-competent, streptozotocin induced, diabetic C57BL/6 recipients. Group 1 allografts survived significantly longer than group 2 (32.2 ± 12.2 versus 14.1 ± 3.3 days, P<0.001 without administration of any systemic immunosuppressive agents. DSCC reduced T cell activation in the renal lymph node, prevented graft infiltrates, modulated inflammatory chemokine and cytokine profiles, and preserved better beta cell function in the islet allografts, but no systemic immunosuppression was observed. In summary, DSCC prolong islet allograft survival without systemic immunosuppression by local modulation of alloimmune responses, enhancing of beta cell survival, and promoting of graft revascularization. This novel finding demonstrates the capacity of easily accessible hair follicle cells to be used as local immunosuppression agents in islet transplantation.

  14. Hair follicle dermal sheath derived cells improve islet allograft survival without systemic immunosuppression.

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    Wang, Xiaojie; Hao, Jianqiang; Leung, Gigi; Breitkopf, Trisia; Wang, Eddy; Kwong, Nicole; Akhoundsadegh, Noushin; Warnock, Garth L; Shapiro, Jerry; McElwee, Kevin J

    2015-01-01

    Immunosuppressive drugs successfully prevent rejection of islet allografts in the treatment of type I diabetes. However, the drugs also suppress systemic immunity increasing the risk of opportunistic infection and cancer development in allograft recipients. In this study, we investigated a new treatment for autoimmune diabetes using naturally immune privileged, hair follicle derived, autologous cells to provide localized immune protection of islet allotransplants. Islets from Balb/c mouse donors were cotransplanted with syngeneic hair follicle dermal sheath cup cells (DSCC, group 1) or fibroblasts (FB, group 2) under the kidney capsule of immune-competent, streptozotocin induced, diabetic C57BL/6 recipients. Group 1 allografts survived significantly longer than group 2 (32.2 ± 12.2 versus 14.1 ± 3.3 days, P < 0.001) without administration of any systemic immunosuppressive agents. DSCC reduced T cell activation in the renal lymph node, prevented graft infiltrates, modulated inflammatory chemokine and cytokine profiles, and preserved better beta cell function in the islet allografts, but no systemic immunosuppression was observed. In summary, DSCC prolong islet allograft survival without systemic immunosuppression by local modulation of alloimmune responses, enhancing of beta cell survival, and promoting of graft revascularization. This novel finding demonstrates the capacity of easily accessible hair follicle cells to be used as local immunosuppression agents in islet transplantation.

  15. Intragraft vascular occlusive sickle crisis with early renal allograft loss in occult sickle cell trait.

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    Kim, Lisa; Garfinkel, Marc R; Chang, Anthony; Kadambi, Pradeep V; Meehan, Shane M

    2011-07-01

    Early renal allograft failure due to sickle cell trait is rare. We present clinical and pathologic findings in 2 cases of early renal allograft failure associated with renal vein thrombosis and extensive erythrocyte sickling. Hemoglobin AS was identified in retrospect. In case 1, a 41-year-old female recipient of a deceased donor renal transplant developed abdominal pain and acute allograft failure on day 16, necessitating immediate nephrectomy. In case 2, the transplanted kidney in a 58-year-old female recipient was noted to be mottled blue within minutes of reperfusion. At 24 hours, the patient was oliguric; and the graft was removed. Transplant nephrectomies had diffuse enlargement with diffuse, nonhemorrhagic, cortical, and medullary necrosis. Extensive sickle vascular occlusion was evident in renal vein branches; interlobar, interlobular, and arcuate veins; vasa recta; and peritubular capillaries. The renal arteries had sickle vascular occlusion in case 1. Glomeruli had only focal sickle vascular occlusion. The erythrocytes in sickle vascular occlusion had abundant cytoplasmic filaments by electron microscopy. Acute rejection was not identified in either case. Protein C and S levels, factor V Leiden, and lupus anticoagulant assays were within normal limits. Hemoglobin analysis revealed hemoglobin S of 21.8% and 25.6%, respectively. Renal allograft necrosis with intragraft sickle crisis, characterized by extensive vascular occlusive erythrocyte sickling and prominent renal vein thrombosis, was observed in 2 patients with sickle cell trait. Occult sickle cell trait may be a risk factor for early renal allograft loss.

  16. The Presence of Recipient-Derived Renal Cells in Kidney Allografts

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    Türkan METE

    2011-09-01

    Full Text Available OBJECTIVE: Stem cells may be involved in the repair processes of renal tissues during various disorders. We aimed to search the presence of recipient originated cells in renal allograft tissues from patients with various types of allograft dysfunction including acute rejection, acute tubular necrosis, calcineurin inhibitor toxicity, and chronic rejection. MATERIAL and METHODS: Eleven kidney transplant recipients were enrolled in the study. Seven patients who had sex-mismatched donors were regarded as the study group and the remaining were the controls (male-male, positive controls, n=2; female-female, negative controls, n=2. Histopathological examinations in the study group had revealed chronic rejection in four patients(together with calcineurin inhibitor toxicity in three and acute rejection, acute tubular necrosis, and cyclosporine toxicity in one patient each. Deparaffi nised biopsy specimens were examined using chromogenic in situ hybridization (CISH method for the XY cocktail probe. RESULTS: Renal cells of positive controls had XY, whereas those of negative controls had XX chromosomal signals. Examination of the biopsy samples from the study group showed variable ratios of recipient-derived tubular(2-76%, interstitial mesenchymal(5-83%, and endothelial cells(1-53%. CONCLUSION: The presence of recipient-derived renal cells in injured kidney allografts suggests that there is a possible dynamic interaction between allograft and stem cells of the recipient. Further studies are needed to clarify the origin and the function of these cells.

  17. Proliferation of CD8-positive T cells in blood vessels of rat renal allografts.

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    Grau, V; Fuchs-Moll, G; Wilker, S; Weimer, R; Padberg, W

    2011-09-01

    It is still disputed in which anatomical compartments of allograft recipients T-cells proliferate. After experimental renal transplantation, host monocytes and lymphocytes accumulate in the lumina of graft blood vessels. In this study, we test the hypothesis that T lymphocytes proliferate in the vascular bed of the graft. Kidneys were transplanted in the Dark Agouti to Lewis rat strain combination, an established experimental model for acute rejection. Isogeneic transplantation was performed as a control. Cells in the S-phase of mitosis were detected in situ three days posttransplantation by pulse-labeling with BrdU and by immunohistochemical detection of the proliferating cell nuclear antigen (PCNA). More than 20% of all T-cells in the lumina of allograft blood vessels incorporated BrdU and approximately 30% of them expressed PCNA. In the blood vessels of isografts as well as in other organs of allograft recipients, only few BrdU(+) cells were detected. A majority of the BrdU(+) cells in graft blood vessels expressed CD8. In conclusion, we demonstrate that CD8(+) T lymphocytes proliferate in the lumina of the blood vessels of renal allografts during the onset of acute rejection.

  18. Microinterferometric characterization of cells isolated from primary hepatomata and from allografts of hepatomata by 4-dimethylaminoazobenzene.

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    Tongiani, R; Chieli, E; Malvaldi, G

    1980-02-15

    Distribution of individual cells according to their solid protoplasmic content has been determined in cell populations isolated from two primary hepatomata by 4-dimethylaminoazobenzene (DAB) and from subcutaneous allografts of two others DAB hepatomata carried for years as transplant lines in rats. In nodular (neoplastic) tissue of the primary hepatomata, the cells maintained the typical distribution of the mammalian hepatocytes in a weight class pattern, but (i) the number of cell clases was reduced due to disappearance of the heavier cells and (ii) the frequency of the light cells was markedly increased with respect to the findings in anodular (non-neoplastic) liver tissue. In the allografts the great majority of the cells had a small content in solids and were normally grouped in one class. It is suggested that a delay in the cell differentiation may be responsible of this change.

  19. Effect of impaction on gene-modified cells seeded on granular bone allografts in vitro and in vivo

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    YUAN Zhen; MAO Yuan-qing; ZHU Zhen-an

    2010-01-01

    Background While attempting to restore bone stock, impaction bone grafting employed during revision joint surgery may result in slow and limited allograft incorporation into host bone. A new approach including gene-modified bone marrow stromal cells (BMSCs) in combination with impaction bone grafting may effectively restore bone stock and improve allograft incorporation. This study aimed to investigate the effect of impaction on gene-modified BMSCs seeded on granular bone allografts in vitro and in vivo.Methods Deep-frozen, granular, cancellous bone allografts from canines were prepared to serve as cell delivery scaffolds and were seeded with green fluorescent protein (GFP) genetically-modified BMSCs to construct cell-allograft composites. The composites were impacted in a simulative, in vitro impaction model and cultured for further analysis under standard conditions. Four Beagle dogs, treated with bilateral, uncemented proximal tibial joint hemiarthroplasty with a prosthesis, were implanted with autologous GFP gene-modified cell-allograft composites to repair the bone cavity around each prosthesis.Results A significant reduction in cell viability was observed after impaction by fluorescence microscopy in vitro.However, there remained a proportion of GFP-positive cells that were viable and functionally active, as evidenced by the secretion of GFP protein in vitro and in vivo.Conclusions Gene-modified BMSCs seeded on granular allografts were able to withstand the impaction forces and to maintain their normal functions in vitro and in vivo, in spite of a partial loss in cell viability.

  20. Donor-specific Regulatory T Cells Acquired from Tolerant Mice Bearing Cardiac allograft Promote Mixed Chimerism and Prolong Intestinal Allograft Survival

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    Xiaofei Shen

    2016-11-01

    Full Text Available The induction of donor-specific transplant tolerance has always been a central problem for small bowel transplantation, which is thought to be the best therapy for end-stage bowel failure. With the development of new tolerance-inducing strategies, mixed chimerism induced by co-stimulation blockade has become most potent for tolerance of allografts such as skin, kidney and heart. However, a lack of clinically available co-stimulation blockers has hindered efficient application in humans. Furthermore, unlike those for other types of solid organ transplantation, strategies to induce robust mixed chimerism for intestinal allografts have not been fully developed. To improve current mixed chimerism induction protocols for future clinical application, we developed a new protocol using donor-specific regulatory T (Treg cells from mice with heart allograft tolerance, clinically available immunosuppressive drugs, and low doses of irradiation. Our results demonstrated that donor-specific Treg cells acquired from tolerant mice after in vitro expansion generate stable chimerism and lead to acceptance of intestinal allograft. Increased intragraft Treg cells and clonal deletion both contribute to the development of small bowel transplantation tolerance.

  1. Ankle arthrodesis fusion rates for mesenchymal stem cell bone allograft versus proximal tibia autograft.

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    Anderson, John J; Boone, Joshua J; Hansen, Myron; Brady, Chad; Gough, Adam; Swayzee, Zflan

    2014-01-01

    Ankle arthrodesis is commonly used in the treatment of ankle arthritis. The present study compared mesenchymal stem cell (MSC) bone allografts and proximal tibia autografts as adjuncts in performing ankle arthrodesis. A total of 109 consecutive ankle fusions performed from 2002 to 2008 were evaluated retrospectively. Of the 109 fusions, 24 were excluded from the present study, leaving 85 patients who had undergone ankle arthrodesis. Of the 85 patients, 41 had received a proximal tibia autograft and 44, an MSC bone allograft. These 2 groups were reviewed and compared retrospectively at least 2 years postoperatively for the overall fusion rate, interval to radiographic fusion, and interval to clinical fusion. A modified and adjusted American College of Foot and Ankle Surgeons ankle scale was used to measure patient satisfaction. The overall fusion rate was 84.1% in the MSC bone allograft group and 95.1% in the proximal tibia autograft group (p = .158). The corresponding mean intervals to radiographic fusion were 13.0 ± 2.5 weeks and 11.3 ± 2.8 weeks (p ≤ .001). The interval to clinical fusion was 13.1 ± 2.1 weeks and 11.0 ± 1.5 weeks (p ≤ .001) in the MSC bone allograft and proximal tibia autograft group, respectively. No statistically significant difference was found in the fusion rates between the MSC bone allograft and proximal tibia autograft groups. Also, no statistically significant difference was found between the preoperative and postoperative scores using a modified and adjusted American College of Foot and Ankle Surgeons ankle scale between the 2 groups (p = .41 and p = .44, respectively). A statistically significant delay to radiographic and clinical fusion was present in the MSC bone allograft group compared with the proximal tibia autograft group; however, no difference was found in patient satisfaction.

  2. Re-exposure to beta cell autoantigens in pancreatic allograft recipients with preexisting beta cell autoantibodies.

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    Mujtaba, Muhammad Ahmad; Fridell, Jonathan; Book, Benita; Faiz, Sara; Sharfuddin, Asif; Wiebke, Eric; Rigby, Mark; Taber, Tim

    2015-11-01

    Re-exposure to beta cell autoantigens and its relevance in the presence of donor-specific antibodies (DSA) in pancreatic allograft recipients is not well known. Thirty-three patients requiring a pancreas transplant were enrolled in an IRB approved study. They underwent prospective monitoring for DSA and beta cell autoantibody (BCAA) levels to GAD65, insulinoma-associated antigen 2 (IA-2), insulin (micro-IAA [mIAA]), and islet-specific zinc transporter isoform-8 (ZnT8). Twenty-five (75.7%) had pre-transplant BCAA. Twenty had a single antibody (mIAA n = 15, GAD65 n = 5); five had two or more BCAA (GAD65 + mIAA n = 2, GAD65 + mIAA+IA-2 n = 2, GA65 + mIAA+IA-2 + ZnT8 = 1). No changes in GAD65 (p > 0.29), IA-2 (>0.16), and ZnT8 (p > 0.07) were observed between pre-transplant and post-transplant at 6 or 12 months. A decrease in mIAA from pre- to post-6 months (p BCAA was observed at one yr. Seven (21.0%) developed de novo DSA. The incidence of DSA was 24% in patients with BCAA vs. 25% in patients without BCAA (p = 0.69). Pancreatic allograft function of patients with vs. without BCAA, and with and without BCAA + DSA was comparable until last follow-up (three yr). Re-exposure to beta cell autoantigens by pancreas transplant may not lead to increased levels or development of new BCAA or pancreatic allograft dysfunction.

  3. Renal allograft rejection: examination of delayed differentiation of Treg and Th17 effector T cells.

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    Pekalski, Marcin; Jenkinson, Sarah E; Willet, Joseph D P; Poyner, Elizabeth F M; Alhamidi, Abdulaziz H; Robertson, Helen; Ali, Simi; Kirby, John A

    2013-03-01

    Antigen presentation after kidney transplantation occurs in lymphoid tissues remote from the allograft, with activated T cells then migrating towards the graft. This study examined the possibility that these activated T cells can differentiate to acquire Th17 or Treg phenotypes after a time consistent with their arrival within renal allograft tissues. An immunocytochemical study was performed to demonstrate the response to intragraft TGF-β and the phenotype of lymphoid cells within rejecting human renal allograft tissue. A series of in vitro experiments was then performed to determine the potential to induce these phenotypes by addition of appropriate cytokines 3days after initial T cell activation. During renal allograft rejection there was a strong response to TGF-β, and both FOXP3 and IL-17A were expressed by separate lymphoid cells in the graft infiltrate. FOXP3 could be induced to high levels by the addition of TGF-β1 3days after the initiation of allogeneic mixed leukocyte culture. This Treg marker was enriched in the sub-population of T cells expressing the cell-surface αE(CD103)β7 integrin. The RORγt transcription factor and IL-17A were induced 3days after T cell activation by the addition of TGF-β1, IL-1β, IL-6 and IL-23; many of these Th17 cells also co-expressed CD103. T cells can develop an effector phenotype following cytokine stimulation 3days after initial activation. This suggests that the intragraft T cell phenotype may be indicative of the prevailing cytokine microenvironment.

  4. Donor liver natural killer cells alleviate liver allograft acute rejection in rats

    Institute of Scientific and Technical Information of China (English)

    Jian-Dong Yu; Tian-Zhu Long; Guo-Lin Li; Li-Hong Lv; Hao-Ming Lin; Yong-Heng Huang; Ya-Jin Chen; Yun-Le Wan

    2011-01-01

    BACKGROUND: Liver enriched natural killer (NK) cells are of high immune activity. However, the function of donor liver NK cells in allogeneic liver transplantation (LTx) remains unclear. METHODS: Ten Gy of whole body gamma-irradiation (WBI) from a 60Co source at 0.6 Gy/min was used for depleting donor-derived leukocytes, and transfusion of purified liver NK cells isolated from the same type rat as donor (donor type liver NK cells, dtlNKs) through portal vein was performed immediately after grafting the irradiated liver. Post-transplant survival observation on recipients and histopathological detection of liver grafts were adoptive to evaluate the biological impact of donor liver NK cells on recipients' survival in rat LTx. RESULTS: Transfusion of dtlNKs did not shorten the survival time among the recipients of spontaneous tolerance model (BN to LEW rat) after rat LTx, but prolonged the liver graft survival among the recipients depleted of donor-derived leukocytes in the acute rejection model (LEW to BN rat). Compared to the recipients in the groups which received the graft depleted of donor-derived leukocytes, better survival and less damage in the allografts were also found among the recipients in the two different strain combinations of liver allograft due to transfusion of dtlNKs. CONCLUSIONS: Donor liver NK cells alone do not exacerbate liver allograft acute rejection. Conversely, they can alleviate it, and improve the recipients' survival.

  5. T-regulatory cell treatment prevents chronic rejection of heart allografts in a murine mixed chimerism model

    OpenAIRE

    Pilat, Nina; Farkas, Andreas M.; Mahr, Benedikt; Schwarz, Christoph; Unger, Lukas; Hock, Karin; Oberhuber, Rupert; Aumayr, Klaus; Wrba, Fritz; Wekerle, Thomas

    2014-01-01

    Background The mixed chimerism approach induces donor-specific tolerance in both pre-clinical models and clinical pilot trials. However, chronic rejection of heart allografts and acute rejection of skin allografts were observed in some chimeric animals despite persistent hematopoietic chimerism and tolerance toward donor antigens in vitro. We tested whether additional cell therapy with regulatory T cells (Tregs) is able to induce full immunologic tolerance and prevent chronic rejection. Metho...

  6. Polymer microlenses for quantifying cell sheet mechanics.

    Science.gov (United States)

    Miquelard-Garnier, Guillaume; Zimberlin, Jessica A; Sikora, Christian B; Wadsworth, Patricia; Crosby, Alfred

    2010-01-01

    Mechanical interactions between individual cells and their substrate have been studied extensively over the past decade; however, understanding how these interactions change as cells interact with neighboring cells in the development of a cell sheet, or early stage tissue, is less developed. We use a recently developed experimental technique for quantifying the mechanics of confluent cell sheets. Living cells are cultured on a thin film of polystyrene [PS], which is attached to a patterned substrate of crosslinked poly(dimethyl siloxane) [PDMS] microwells. As cells attach to the substrate and begin to form a sheet, they apply sufficient contractile force to buckle the PS film over individual microwells to form a microlens array. The curvature for each microlens is measured by confocal microscopy and can be related to the strain and stress applied by the cell sheet using simple mechanical analysis for the buckling of thin films. We demonstrate that this technique can provide insight into the important materials properties and length scales that govern cell sheet responses, especially the role of stiffness of the substrate. We show that intercellular forces can lead to significantly different behaviors than the ones observed for individual cells, where focal adhesion is the relevant parameter.

  7. Resistance of Foxp3+ regulatory T cells to Nur77-induced apoptosis promotes allograft survival.

    Directory of Open Access Journals (Sweden)

    Ran Tao

    Full Text Available The NR4A nuclear receptor family member Nur77 (NR4A1 promotes thymocyte apoptosis during negative selection of autoreactive thymocytes, but may also function in mature extrathymic T cells. We studied the effects of over-expression of Nur77 on the apoptosis of murine peripheral T cells, including thymic-derived Foxp3+ regulatory (Treg cells. Overexpression of Nur77 in the T cell lineage decreased numbers of peripheral CD4 and CD8 T cells by approximately 80% compared to wild-type (WT mice. However, the proportions of Treg cells were markedly increased in the thymus (61% of CD4+Foxp3+ singly positive thymocytes vs. 8% in WT and secondary lymphoid organs (40-50% of CD4+Foxp3+ T cells vs. 7-8% in WT of Nur77 transgenic (Nur77Tg mice, and immunoprecipitation studies showed Nur77 was associated with a recently identified HDAC7/Foxp3 transcriptional complex. Upon activation through the T cell receptor in vitro or in vivo, Nur77Tg T cells showed only marginally decreased proliferation but significantly increased apoptosis. Fully allogeneic cardiac grafts transplanted to Nur77Tg mice survived long-term with well-preserved structure, and recipient splenocytes showed markedly enhanced apoptosis and greatly reduced anti-donor recall responses. Allografts in Nur77Tg recipients had significantly increased expression of multiple Treg-associated genes, including Foxp3, Foxp1, Tip60 and HDAC9. Allograft rejection was restored by CD25 monoclonal antibody therapy, indicating that allograft acceptance was dependent upon Treg function in Nur77Tg recipients. These data show that compared to conventional CD4 and CD8 T cells, Foxp3+ Tregs are relatively resistant to Nur77-mediated apoptosis, and that tipping the balance between the numbers of Tregs and responder T cells in the early period post-transplantation can determine the fate of the allograft. Hence, induced expression of Nur77 might be a novel means to achieve long-term allograft survival.

  8. Rapamycin Prolongs Cardiac Allograft Survival in a Mouse Model by Inducing Myeloid-Derived Suppressor Cells.

    Science.gov (United States)

    Nakamura, T; Nakao, T; Yoshimura, N; Ashihara, E

    2015-09-01

    Mammalian target of rapamycin (mTOR) inhibitors are the main immunosuppressive drugs for organ transplant recipients. Nevertheless, the mechanisms by which mTOR inhibitors induce immunosuppression is not fully understood. Myeloid-derived suppressor cells (MDSCs) maintain host immunity; however, the relationship between mTOR inhibitors and MDSCs is unclear. Here, the results from a murine cardiac transplantation model revealed that rapamycin treatment (3 mg/kg, intraperitoneally on postoperative days 0, 2, 4, and 6) led to the recruitment of MDSCs and increased their expression of inducible nitric oxide synthase (iNOS). Immunohistochemical analysis revealed that rapamycin induced the migration of iNOS-expressing MDSCs into the subintimal space within the allograft vessels, resulting in a significant prolongation of graft survival compared with that in the untreated group (67 days vs. 7 days, respectively). These effects were counterbalanced by the administration of an anti-Gr-1, which reduced allograft survival to 21 days. Moreover, adoptive transcoronary arterial transfer of MDSCs from rapamycin-treated recipients prolonged allograft survival; this increase was reversed by the anti-Gr-1 antibody. Finally, co-administration of rapamycin and a mitogen-activated protein kinase kinase (MEK) inhibitor trametinib reversed rapamycin-mediated MDSC recruitment. Thus, the mTOR and Raf/MEK/extracellular signal regulated kinase (ERK) signaling pathways appear to play an important role in MDSC expansion.

  9. Prolonged renal allograft survival by donor interleukin-6 deficiency: association with decreased alloantibodies and increased intragraft T regulatory cells.

    Science.gov (United States)

    Wang, Hao; Guan, Qiunong; Lan, Zhu; Li, Shuyuan; Ge, Wei; Chen, Huifang; Nguan, Christopher Y C; Du, Caigan

    2012-01-15

    Both humoral and cellular immune responses are involved in renal allograft rejection. Interleukin (IL)-6 is a regulatory cytokine for both B and Foxp3 (forkhead box P3)-expressing regulatory T (Treg) cells. This study was designed to investigate the impact of donor IL-6 production on renal allograft survival. Donor kidneys from IL-6 knockout (KO) vs. wild-type (WT) C57BL/6 mice (H-2(b)) were orthotopically transplanted to nephrotomized BALB/c mice (H-2(d)). Alloantibodies and Treg cells were examined by fluorescence-activated cell sorting analysis. Graft survival was determined by the time to graft failure. Here, we showed that a deficiency in IL-6 expression in donor kidneys significantly prolonged renal allograft survival compared with WT controls. IL-6 protein was upregulated in renal tubules and endothelium of renal allografts following rejection, which correlated with an increase in serum IL-6 compared with that in those receiving KO grafts or naive controls. The absence of graft-producing IL-6 or lower levels of serum IL-6 in the recipients receiving IL-6 KO allografts was associated with decreased circulating anti-graft alloantibodies and increased the percentage of intragraft CD4(+)CD25(+)Foxp3(+) Treg cells compared with those with WT allografts. In conclusion, the lack of graft-producing IL-6 significantly prolongs renal allograft survival, which is associated with reduced alloantibody production and/or increased intragraft Treg cell population, implying that targeting donor IL-6 may effectively prevent both humoral and cellular rejection of kidney transplants.

  10. Transduction of interleukin-10 through renal artery attenuates vascular neointimal proliferation and infiltration of immune cells in rat renal allograft.

    Science.gov (United States)

    Xie, Jingxin; Li, Xueyi; Meng, Dan; Liang, Qiujuan; Wang, Xinhong; Wang, Li; Wang, Rui; Xiang, Meng; Chen, Sifeng

    2016-08-01

    Renal transplantation is the treatment of choice for end-stage renal failure. Although acute rejection is not a major issue anymore, chronic rejection, especially vascular rejection, is still a major factor that might lead to allograft dysfunction on the long term. The role of the local immune-regulating cytokine interleukin-10 (IL-10) in chronic renal allograft is unclear. Many clinical observations showed that local IL-10 level was negatively related to kidney allograft function. It is unknown this negative relationship was the result of immunostimulatory property or insufficient immunosuppression property of local IL-10. We performed ex vivo transduction before transplantation through artery of the renal allograft using adeno-associated viral vectors carrying IL-10 gene. Twelve weeks after transplantation, we found intrarenal IL-10 gene transduction significantly inhibited arterial neointimal proliferation, the number of occluded intrarenal artery, interstitial fibrosis, peritubular capillary congestion and glomerular inflammation in renal allografts compared to control allografts receiving PBS or vectors carrying YFP. IL-10 transduction increased serum IL-10 level at 4 weeks but not at 8 and 12 weeks. Renal IL-10 level increased while serum creatinine decreased significantly in IL-10 group at 12 weeks compared to PBS or YFP controls. Immunohistochemical staining showed unchanged total T cells (CD3) and B cells (CD45R/B220), decreased cytotoxic T cells (CD8), macrophages (CD68) and increased CD4+ and FoxP3+ cells in IL-10 group. In summary, intrarenal IL-10 inhibited the allograft rejection while modulated immune response.

  11. Interleukin-10 modified dendritic cells induce allo-hyporesponsiveness and prolong small intestine allograft survival

    Institute of Scientific and Technical Information of China (English)

    Min Zhu; Ming-Fa Wei; Fang Liu; Hui-Fen Shi; Guo Wang

    2003-01-01

    AIM: To investigate whether TL-10-transduced dendritic cells (DCs) could induce tolerogenicity and prolong allograft survival in rat intestinal transplantation.METHODS: Spleen-derived DCs were prepared and genetically modified by hTL-10 gene. The level of IL-10 expression was quantitated by ELTSA. DC function was assessed by MTT in mixed leukocyte reaction. Allogeneic T-cell apoptosis was examined by flow cytometric analysis. Seven days before heterotopic intestinal transplantation, 2x106 donor-derived IL-10-DC were injected intravenously, then transplantation was performed between SD donor and Wistar recipient.RESULTS: Compared with untransduced DC, IL-10-DC could suppress allogeneic mixed leukocyte reaction (MLR). The inhibitory effect was the most striking with the stimulator/effector (S/F) ratio of 1:10. The inhibition rate was 33.25 %,41.19 % (P<0.01) and 22.92 % with the S/E ratio of 1:1,1:10 and 1:50 respectively. At 48 hours and 72 hours by flow cytometry counting, apoptotic T cells responded to IL-10-DC in MLR were 13.8 % and 30.1%, while untransduced group did not undergo significant apoptosis (P<0.05). IL-10-DC pretreated recipients had a moderate survival prolongation with a mean allograft survival of 19.8 days (P<0.01),compared with 7.3±2.4 days in control group and 8.3±2.9days in untransduced DC group. Rejection occurred in the control group within three days. The difference between untreated DC group and control group was not significant.CONCLUSION: IL-10-DC can induce allogenic T-cell hyporesponsiveness in vitro and apoptosis may be involved in it. IL-10-DC pretreatment can prolong intestinal allograft survival in the recipient.

  12. Autologous Dendritic Cells Prolong Allograft Survival Through Tmem176b-Dependent Antigen Cross-Presentation

    Science.gov (United States)

    Charnet, P.; Savina, A.; Tilly, G.; Gautreau, L.; Carretero-Iglesia, L.; Beriou, G.; Cebrian, I.; Cens, T.; Hepburn, L.; Chiffoleau, E.; Floto, R. A.; Anegon, I.; Amigorena, S.; Hill, M.; Cuturi, M. C.

    2015-01-01

    The administration of autologous (recipient-derived) tolerogenic dendritic cells (ATDCs) is under clinical evaluation. However, the molecular mechanisms by which these cells prolong graft survival in a donor-specific manner is unknown. Here, we tested mouse ATDCs for their therapeutic potential in a skin transplantation model. ATDC injection in combination with anti-CD3 treatment induced the accumulation of CD8+CD11c+ T cells and significantly prolonged allograft survival. TMEM176B is an intracellular protein expressed in ATDCs and initially identified in allograft tolerance. We show that Tmem176b−/− ATDCs completely failed to trigger both phenomena but recovered their effect when loaded with donor peptides before injection. These results strongly suggested that ATDCs require TMEM176B to cross-present antigens in a tolerogenic fashion. In agreement with this, Tmem176b−/− ATDCs specifically failed to cross-present male antigens or ovalbumin to CD8+ T cells. Finally, we observed that a Tmem176b-dependent cation current controls phagosomal pH, a critical parameter in cross-presentation. Thus, ATDCs require TMEM176B to cross-present donor antigens to induce donor-specific CD8+CD11c+ T cells with regulatory properties and prolong graft survival. PMID:24731243

  13. Immature CD4+ dendritic cells conditioned with donor kidney antigen prolong renal allograft survival in rats

    Institute of Scientific and Technical Information of China (English)

    WANG Tao; XU Lin; LI Heng; HUANG Zheng-yu; ZHANG Sheng-ping; MIAO Bin; NA Ning

    2012-01-01

    Background AIIogeneic transplant rejection is currently a major problem encountered during organ transplantation.The dendritic cell (DC) is the most effective powerful known professional antigen-presenting cell,and recent studies have found that DCs can also induce immune tolerance,and avoid or reduce the degree of transplant rejection.The aim of this study was to evaluate the effect of transfused immature CD4+ DCs on renal allografts in the rat model.Methods In this study,we induced CD4+ immature DCs from rat bone marrow cells by a cytokine cocktail.The immature CD4+ DCs were identified by morphological analysis and then the suppressive activity of these cells conditioned with donor kidney antigen was evaluated in vitro and in vivo.Results Immature CD4+ DCs conditioned with donor kidney antigen possessed immunosuppressive activity in vitro and they were able to prolong renal transplant survival in an allograft rat model in vivo.Conclusions Our study provides new information on efficacious renal transplantation,which might be useful for understanding the function of immature CD4+ DCs in modulating renal transplant rejection and improving clinical outcome in future studies.

  14. Prolongation of liver allograft survival by dendritic cells modified with NF-κB decoy oligodeoxynucleotides

    Institute of Scientific and Technical Information of China (English)

    Ming-Qing Xu; Yu-Ping Suo; Jian-Ping Gong; Ming-Man Zhang; Lü-Nan Yan

    2004-01-01

    AIM: To induce the tolerance of rat liver allograft by dendritic cells (DCs) modified with NF-κB decoy oligodeoxynucleotides (ODNs).METHODS: Bone marrow (BM)-derived DCs from SD rats were propagated in the presence of GM-CSF or GM-CSF+IL-4to obtain immature DCs or mature DCs. GM-CSF+IL-4-propagated DCs were treated with double-strand NF-κB decoy ODNs containing two NF-κB binding sites or scrambled ODNs to ascertain whether NF-κB decoy ODNs might prevent DC maturation. GM-CSF-propagated DCs, GMCSF+NF-κB decoy ODNs or scrambled ODNs-propagated DCs were treated with LPS for 18 h to determine whether NF-κB decoy ODNs could prevent LPS-induced IL-12production in DCs. NF-κB binding activities, costimulatory molecule (CD40, CD80, CD86) surface expression, IL-12protein expression and allostimulatory capacity of DCs were measured with electrophoretic mobility shift assay (EMSA),flow cytometry, Western blotting, and mixed lymphocyte reaction (MLR), respectively. GM-CSF-propagated DCs, GMCSF+IL-4 -propagated DCs, and GM-CSF+NF-κB decoy ODNs or scrambled ODNs-propagated DCs were injected intravenously into recipient LEW rats 7 d prior to liver transplantation and immediately after liver transplantation.Histological grading of liver graft rejection was determined 7 d after liver transplantation. Expression of IL-2, IL-4 and IFN-γ mRNA in liver graft and in recipient spleen was analyzed by semiquantitative RT-PCR. Apoptosis of liver allograft-infiltrating cells was measured with TUNEL staining.RESULTS: GM-CSF-propagated DCs, GM-CSF+NF-κB decoy ODNs-propagated DCs and GM-CSF+ scrambled ODNspropagated DCs exhibited features of immature DCs, with similar low level of costimulatory molecule(CD40, CD80,CD86) surface expression, absence of NF-κB activation,and few allocostimulatory activities. GM-CSF+IL-4-propagated DCs displayed features of mature DCs, with high levels of costimulatory molecule (CD40, CD80, CD86) surface expression, marked NF-κB activation, and

  15. Relevance of activated hepatic stellate cells in predicting the development of pediatric liver allograft fibrosis.

    Science.gov (United States)

    Venturi, Carla; Reding, Raymond; Quinones, Jorge Abarca; Sokal, Etienne; Rahier, Jacques; Bueno, Javier; Sempoux, Christine

    2016-06-01

    Activated hepatic stellate cells (HSCs) are the main collagen-producing cells in liver fibrogenesis. With the purpose of analyzing their presence and relevance in predicting liver allograft fibrosis development, 162 liver biopsies of 54 pediatric liver transplantation (LT) recipients were assessed at 6 months, 3 years, and 7 years after LT. The proportion of activated HSCs, identified by α-smooth muscle actin (ASMA) immunostaining, and the amount of fibrosis, identified by picrosirius red (PSR%) staining, were determined by computer-based morphometric analysis. Fibrosis was also staged by using the semiquantitative liver allograft fibrosis score (LAFSc), specifically designed to score fibrosis in the pediatric LT population. Liver allograft fibrosis displayed progression over time by PSR% (P ASMA expression decreased in the long term, with inverse evolution with respect to fibrosis (P ASMA-positive HSCs area ≥ 8% at 6 months (n = 20) developed a higher fibrosis proportion compared to those with ASMA-positive HSCs area ≤ 8% (n = 34) at the same period of time and in the long term (P = 0.03 and P ASMA expression ≥ 8% at 6 months was found to be an independent risk factor for 7-year fibrosis development by PSR% (r(2) = 0.5; P ASMA expression ≥ 8% at 3 years showed an association with the development of fibrosis at 7 years (P = 0.02). In conclusion, there is a high proportion of activated HSCs in pediatric LT recipients. ASMA ≥ 8% at 6 months seems to be a risk factor for early and longterm fibrosis development. In addition, activated HSCs showed inverse evolution with respect to fibrosis in the long term. Liver Transplantation 22 822-829 2016 AASLD.

  16. In vitro donor-specific hyporesponsiveness and T cell subsets in renal allograft recipients.

    Science.gov (United States)

    Bas, J; Mestre, M; Griñó, J M; Massip, E; Castelao, A M; Romeu, A; González, L; Valls, A; Buendía, E

    1993-01-01

    In order to assess the immune mechanisms triggered by an immunosuppressive regimen consisting of prophylactic antilymphocyte globulin plus low-dose cyclosporine A and steroids, we studied the short-term evolution of both, anti donor in vitro alloresponse and peripheral blood T cell subsets in 21 recipients of a cadaveric kidney allograft. Spleen cells from cadaveric donors and peripheral blood lymphocytes from the respective recipients pretransplant (pre-Tx), at three and six months posttransplant (post-Tx) were obtained to perform one-way mixed lymphocyte cultures and flow cytometry analysis of lymphocyte subsets. The results indicated the development of donor-specific mixed lymphocyte culture (MLC) hyporesponsiveness as early as three months post-Tx, paralleled by a decrease in CD4+CD29+ helper-inducer cells and by an increase in CD8+CD45RA+ suppressor lymphocytes in peripheral blood. These changes were reflected in a very good clinical outcome of the patients. The present results further suggest that suppression of the immune system just before transplantation is a suitable method to induce early specific hyporesponsiveness to the allograft.

  17. Laminin-521 Promotes Rat Bone Marrow Mesenchymal Stem Cell Sheet Formation on Light-Induced Cell Sheet Technology

    Directory of Open Access Journals (Sweden)

    Zhiwei Jiang

    2017-01-01

    Full Text Available Rat bone marrow mesenchymal stem cell sheets (rBMSC sheets are attractive for cell-based tissue engineering. However, methods of culturing rBMSC sheets are critically limited. In order to obtain intact rBMSC sheets, a light-induced cell sheet method was used in this study. TiO2 nanodot films were coated with (TL or without (TN laminin-521. We investigated the effects of laminin-521 on rBMSCs during cell sheet culturing. The fabricated rBMSC sheets were subsequently assessed to study cell sheet viability, reattachment ability, cell sheet thickness, collagen type I deposition, and multilineage potential. The results showed that laminin-521 could promote the formation of rBMSC sheets with good viability under hyperconfluent conditions. Cell sheet thickness increased from an initial 26.7 ± 1.5 μm (day 5 up to 47.7 ± 3.0 μm (day 10. Moreover, rBMSC sheets maintained their potential of osteogenic, adipogenic, and chondrogenic differentiation. This study provides a new strategy to obtain rBMSC sheets using light-induced cell sheet technology.

  18. De Novo Renal Cell Carcinoma in a Kidney Allograft 20 Years after Transplant

    Directory of Open Access Journals (Sweden)

    Masataka Banshodani

    2015-01-01

    Full Text Available Renal cell carcinoma (RCC in a kidney allograft is rare. We report the successful diagnosis and treatment of a de novo RCC in a nonfunctioning kidney transplant 20 years after engraftment. A 54-year-old man received a kidney transplant from his mother when he was 34 years old. After 10 years, chronic rejection resulted in graft failure, and the patient became hemodialysis-dependent. Intravenous contrast-enhanced computed tomography (CT for the evaluation of gastrointestinal symptoms revealed a solid 13 mm tumor in the kidney graft. The tumor was confirmed on ultrasound examination. This tumor had not been detected on a surveillance noncontrast CT scan. Needle biopsy showed that the tumor was an RCC. Allograft nephrectomy was performed. Pathological examination showed that the tumor was a Fuhrman Grade 2 RCC. XY-fluorescence hybridization analysis of the RCC showed that the tumor cells were of donor origin. One year after the surgery, the patient is alive and has no evidence of tumor recurrence. Regardless of whether a kidney transplant is functioning, it should periodically be imaged for RCC throughout the recipient’s lifetime. In our experience, ultrasonography or CT with intravenous contrast is better than CT without contrast for the detection of tumor in a nonfunctioning kidney transplant.

  19. Utility of Iron Staining in Identifying the Cause of Renal Allograft Dysfunction in Patients with Sickle Cell Disease

    Directory of Open Access Journals (Sweden)

    Yingchun Wang

    2015-01-01

    Full Text Available Sickle cell nephropathy (SCN is associated with iron/heme deposition in proximal renal tubules and related acute tubular injury (ATI. Here we report the utility of iron staining in differentiating causes of renal allograft dysfunction in patients with a history of sickle cell disease. Case 1: the patient developed acute allograft dysfunction two years after renal transplant. Her renal biopsy showed ATI, supported by patchy loss of brush border and positive staining of kidney injury molecule-1 in proximal tubular epithelial cells, where diffuse increase in iron staining (2+ was present. This indicated that ATI likely resulted from iron/heme toxicity to proximal tubules. Electron microscope confirmed aggregated sickle RBCs in glomeruli, indicating a recurrent SCN. Case 2: four years after renal transplant, the patient developed acute allograft dysfunction and became positive for serum donor-specific antibody. His renal biopsy revealed thrombotic microangiopathy (TMA and diffuse positive C4d stain in peritubular capillaries. Iron staining was negative in the renal tubules, implying that TMA was likely associated with acute antibody-mediated rejection (AAMR, type 2 rather than recurrent SCN. These case reports imply that iron staining is an inexpensive but effective method in distinguishing SCN-associated renal injury in allograft kidney from other etiologies.

  20. Critical role for CD8 T cells in allograft acceptance induced by DST and CD40/CD154 costimulatory blockade.

    Science.gov (United States)

    Gao, Donghong; Lunsford, Keri E; Eiring, Anna M; Bumgardner, Ginny L

    2004-07-01

    Donor-specific transfusion (DST) and CD40/CD154 costimulation blockade is a powerful immunosuppressive strategy which prolongs survival of many allografts. The efficacy of DST and anti-CD154 mAb for prolongation of hepatocellular allograft survival was only realized in C57BL/6 mice that have both CD4- and CD8-dependent pathways available (median survival time, MST, 82 days). Hepatocyte rejection in CD8 KO mice which is CD4-dependent was not suppressed by DST and anti-CD154 mAb treatment (MST, 7 days); unexpectedly DST abrogated the beneficial effects of anti-CD154 mAb for suppression of hepatocyte rejection (MST, 42 days) and on donor-reactive alloantibody production. Hepatocyte rejection in CD4 KO mice which is CD8-dependent was suppressed by treatment with DST and anti-CD154 mAb therapy (MST, 35 days) but did not differ significantly from immunotherapy with anti-CD154 mAb alone (MST, 32 days). Induction of hepatocellular allograft acceptance by DST and anti-CD154 mAb immunotherapy was dependent on host CD8(+) T cells, as demonstrated by CD8 depletion studies in C57BL/6 mice (MST, 14 days) and CD8 reconstitution of CD8 KO mice (MST, 56 days). These studies demonstrate that both CD4(+) and CD8(+) T-cell subsets contribute to induction of hepatocellular allograft acceptance by this immunotherapeutic strategy.

  1. Allograft inflammatory factor 1 is a regulator of transcytosis in M cells

    Science.gov (United States)

    Kishikawa, Sari; Sato, Shintaro; Kaneto, Satoshi; Uchino, Shigeo; Kohsaka, Shinichi; Nakamura, Seiji; Kiyono, Hiroshi

    2017-01-01

    M cells in follicle-associated epithelium (FAE) are specialized antigen-sampling cells that take up intestinal luminal antigens. Transcription factor Spi-B regulates M-cell maturation, but the molecules that promote transcytosis within M cells are not fully identified. Here we show that mouse allograft inflammatory factor 1 (Aif1) is expressed by M cells and contributes to M-cell transcytosis. FAE in Aif1−/− mice has suppressed uptake of particles and commensal bacteria, compared with wild-type mice. Translocation of Yersinia enterocolitica, but not of Salmonella enterica serovar Typhimurium, leading to the generation of antigen-specific IgA antibodies, is also diminished in Aif1-deficient mice. Although β1 integrin, which acts as a receptor for Y. enterocolitica via invasin protein, is expressed on the apical surface membranes of M cells, its active form is rarely found in Aif1−/− mice. These findings show that Aif1 is important for bacterial and particle transcytosis in M cells. PMID:28224999

  2. Use of FK506 and bone marrow mesenchymal stem cells for rat hind limb allografts

    Institute of Scientific and Technical Information of China (English)

    Youxin Song; Zhujun Wang; Zhixue Wang; Hong Zhang; Xiaohui Li; Bin Chen

    2012-01-01

    Dark Agouti rat donor hind limbs were orthotopically transplanted into Lewis rat recipients to verify the effects of bone marrow mesenchymal stem cells on neural regeneration and functional recovery of allotransplanted limbs in the microenvironment of immunotolerance. bone marrow mesenchymal stem cells were intramuscularly (gluteus maximus) injected with FK506 (tacrolimus) daily, and were transplanted to the injured nerves. Results indicated that the allograft group not receiving therapy showed severe rejection, with transplanted limbs detaching at 10 days after transplantation with complete necrosis. The number of myelinated axons and Schwann cells in the FK506 and FK506 + bone marrow mesenchymal stem cells groups were significantly increased. We observed a lesser degree of gastrocnemius muscle degeneration, and increased polymorphic fibers along with other pathological changes in the FK506 + bone marrow mesenchymal stem cells group. The FK506 + bone marrow mesenchymal stem cells group showed significantly better recovery than the autograft and FK506 groups. The results demonstrated that FK506 improved the immune microenvironment. FK506 combined with bone marrow mesenchymal stem cells significantly promoted sciatic nerve regeneration, and improved sensory recovery and motor function in hind limb allotransplant.

  3. Clinical utility of labeled cells for detection of allograft rejection and myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Fawwaz, R.A.

    1984-07-01

    The choice of a specific radiolabeled blood component for use in detection of allograft rejection depends on several factors including the immunosuppressive agents used, the type of organ allografted, and particularly the length of time the allograft resides in the host and the duration of rejection. To date, only the use of 111In-labeled platelets in renal allograft recipients immunosuppressed with azathioprine and corticosteroids has shown clinical promise in the detection of early allograft rejection. Radiolabeled blood components are unlikely to play a significant role in detection of myocardial infarction. The use of these agents for monitoring therapeutic interventions or as indicators of prognosis in patients with myocardial infarction continues to be investigated.

  4. Emulating Native Periosteum Cell Population and Subsequent Paracrine Factor Production To Promote Tissue Engineered Periosteum-Mediated Allograft Healing

    OpenAIRE

    Hoffman, Michael D.; Benoit, Danielle S.W.

    2015-01-01

    Emulating autograft healing within the context of decellularized bone allografts has immediate clinical applications in the treatment of critical-sized bone defects. The periosteum, a thin, osteogenic tissue that surrounds bone, houses a heterogeneous population of stem cells and osteoprogenitors. There is evidence that periosteum-cell derived paracrine factors, specifically vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2), orchestrate autograft healing throug...

  5. Alefacept promotes immunosuppression-free renal allograft survival in nonhuman primates via depletion of recipient memory T cells.

    Science.gov (United States)

    Lee, S; Yamada, Y; Tonsho, M; Boskovic, S; Nadazdin, O; Schoenfeld, D; Cappetta, K; Atif, M; Smith, R-N; Cosimi, A B; Benichou, G; Kawai, T

    2013-12-01

    Renal allograft tolerance has been achieved in MHC-mismatched primates via nonmyeloablative conditioning beginning 6 days prior to planned kidney and donor bone marrow transplantation (DBMT). To extend the applicability of this approach to deceased donor transplantation, we recently developed a novel-conditioning regimen, the "delayed protocol" in which donor bone marrow (DBM) is transplanted several months after kidney transplantation. However, activation/expansion of donor-reactive CD8(+) memory T cells (TMEM) occurring during the interval between kidney and DBM transplantation impaired tolerance induction using this strategy. In the current study, we tested whether, Alefacept, a fusion protein which targets LFA-3/CD2 interactions and selectively depletes CD2(high) CD8(+) effector memory T cells (TEM) could similarly induce long-term immunosuppression-free renal allograft survival but avoid the deleterious effects of anti-CD8 mAb treatment. We found that Alefacept significantly delayed the expansion of CD2(high) cells including CD8(+) TEM while sparing naïve CD8(+) T and NK cells and achieved mixed chimerism and long-term immunosuppression-free renal allograft survival. In conclusion, elimination of CD2(high) T cells represents a promising approach to prevent electively the expansion/activation of donor-reactive TEM and promotes tolerance induction via the delayed protocol mixed chimerism approach.

  6. Donor bone marrow-derived dendritic cells prolong corneal allograft survival and promote an intragraft immunoregulatory milieu.

    Science.gov (United States)

    O'Flynn, Lisa; Treacy, Oliver; Ryan, Aideen E; Morcos, Maurice; Cregg, Marese; Gerlach, Jared; Joshi, Lokesh; Nosov, Mikhail; Ritter, Thomas

    2013-11-01

    Investigations into cell therapies for application in organ transplantation have grown. Here, we describe the ex vivo generation of donor bone marrow-derived dendritic cells (BMDCs) and glucocorticoid-treated BMDCs with potent immunomodulatory properties for application in allogeneic transplantation. BMDCs were treated with dexamethasone (Dexa) to induce an immature, maturation-resistant phenotype. BMDC and Dexa BMDC phenotype, antigen presenting cell function, and immunomodulatory properties were fully characterized. Both populations display significant immunomodulatory properties, including, but not limited to, a significant increase in mRNA expression of programmed death-ligand 1 and indoleamine 2,3-dioxygenase. BMDCs and Dexa BMDCs display a profound impaired capacity to stimulate allogeneic lymphocytes. Moreover, in a fully MHC I/II mismatched rat corneal transplantation model, injection of donor-derived, untreated BMDC or Dexa BMDCs (1 × 10(6) cells, day -7) significantly prolonged corneal allograft survival without the need for additional immunosuppression. Although neovascularization was not reduced and evidence of donor-specific alloantibody response was detected, a significant reduction in allograft cellular infiltration combined with a significant increase in the ratio of intragraft FoxP3-expressing regulatory cells was observed. Our comprehensive analysis demonstrates the novel cellular therapeutic approach and significant effect of donor-derived, untreated BMDCs and Dexa BMDCs in preventing corneal allograft rejection.

  7. The ratio of circulating regulatory T cells (Tregs)/Th17 cells is associated with acute allograft rejection in liver transplantation.

    Science.gov (United States)

    Wang, Ying; Zhang, Min; Liu, Zhen-Wen; Ren, Wei-Guo; Shi, Yan-Chao; Sun, Yan-Ling; Wang, Hong-Bo; Jin, Lei; Wang, Fu-Sheng; Shi, Ming

    2014-01-01

    CD4(+)CD25(+)FoxP3(+) regulatory T cells (Tregs) and Th17 cells are known to be involved in the alloreactive responses in organ transplantation, but little is known about the relationship between Tregs and Th17 cells in the context of liver alloresponse. Here, we investigated whether the circulating Tregs/Th17 ratio is associated with acute allograft rejection in liver transplantation. In present study, thirty-eight patients who received liver transplant were enrolled. The patients were divided into two groups: acute allograft rejection group (Gr-AR) (n = 16) and stable allograft liver function group (Gr-SF) (n = 22). The frequencies of circulating Tregs and circulating Th17 cells, as well as Tregs/Th17 ratio were determined using flow cytometry. The association between Tregs/Th17 ratio and acute allograft rejection was then analyzed. Our results showed that the frequency of circulating Tregs was significantly decreased, whereas the frequency of circulating Th17 cells was significantly increased in liver allograft recipients who developed acute rejection. Tregs/Th17 ratio had a negative correlation with liver damage indices and the score of rejection activity index (RAI) after liver transplantation. In addition, the percentages of CTLA-4(+), HLA-DR(+), Ki67(+), and IL-10(+) Tregs were higher in Gr-SF group than in Gr-AR group. Our results suggested that the ratio of circulating Tregs/Th17 cells is associated with acute allograft rejection, thus the ratio may serve as an alternative marker for the diagnosis of acute rejection.

  8. Sex determination by SRY PCR and sequencing of Tasmanian devil facial tumour cell lines reveals non-allograft transmission.

    Science.gov (United States)

    Cui, Xianlan; Wang, Yunfeng; Hua, Bobby; Miller, Webb; Zhao, Yan; Cui, Hongyu; Kong, Xiangang

    2016-05-20

    Devil facial tumour disease (DFTD) is an infectious tumour disease and was hypothesised to be transmitted by allograft during biting based on two cytogenetic findings of DFTD tumours in 2006. It was then believed that DFTD tumours were originally from a female devil. In this study the devil sex-determining region Y (SRY) gene was PCR amplified and sequenced, and six pairs of devil SRY PCR primers were used for detection of devil SRY gene fragments in purified DFTD tumour cell lines. Using three pairs of devil SRY PCR primers, devil SRY gene sequence was detected by PCR and sequencing in genomic DNA of DFTD tumour cell lines from six male devils, but not from six female devils. Four out of six DFTD tumour cell lines from male devils contained nucleotides 288-482 of the devil SRY gene, and another two DFTD tumour cell lines contained nucleotides 381-577 and 493-708 of the gene, respectively. These results indicate that the different portions of the SRY gene in the DFTD tumours of the male devils were originally from the male hosts, rejecting the currently believed DFTD allograft transmission theory. The reasons why DFTD transmission was incorrectly defined as allograft are discussed.

  9. Repair of peripheral nerve defects with chemically extracted acellular nerve allografts loaded with neurotrophic factors-transfected bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    Yan-ru Zhang; Ka Ka; Ge-chen Zhang; Hui Zhang; Yan Shang; Guo-qiang Zhao; Wen-hua Huang

    2015-01-01

    Chemically extracted acellular nerve allografts loaded with brain-derived neurotrophic fac-tor-transfected or ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells have been shown to repair sciatic nerve injury better than chemically extracted acellular nerve allografts alone, or chemically extracted acellular nerve allografts loaded with bone marrow mesenchymal stem cells. We hypothesized that these allografts compounded with both brain-derived neurotrophic factor- and ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells may demonstrate even better effects in the repair of peripheral nerve injury. We cultured bone marrow mesenchymal stem cells expressing brain-derived neuro-trophic factor and/or ciliary neurotrophic factor and used them to treat sciatic nerve injury in rats. We observed an increase in sciatic functional index, triceps wet weight recovery rate, myelin thickness, number of myelinated nerve ifbers, amplitude of motor-evoked potentials and nerve conduction velocity, and a shortened latency of motor-evoked potentials when al-lografts loaded with both neurotrophic factors were used, compared with allografts loaded with just one factor. Thus, the combination of both brain-derived neurotrophic factor and cili-ary neurotrophic factor-transfected bone marrow mesenchymal stem cells can greatly improve nerve injury.

  10. In vivo effects of high-dose steroids on nucleic acid content of immunocompetent cells of renal allograft recipients

    Energy Technology Data Exchange (ETDEWEB)

    Walle, A.J.; Wong, G.Y.; Suthanthiran, M.; Rubin, A.L.; Stenzel, K.H.

    1988-03-01

    High-dose steroids administered to renal allograft recipients for treatment of acute graft rejection episodes may affect cell cycle progression of peripheral blood mononuclear (PBM) cells. DNA synthesis and cellular DNA and RNA contents of PBM cells were measured in 8 patients during clinically stable periods, and in another 10 patients both during acute rejection episodes and during 7 days of administration of high-dose steroids. Improved renal function documented successful reversal of the rejection episodes in the 10 patients. Compared with the stable patients, the rejecting patients had higher numbers of cells undergoing clonal expansion--namely, higher proportions of G1-cells and of proliferating, or S, G2, and M (SG2M) cells. Steroid treatment had no acute effects on proportions of G1 or SG2M cells in vivo or on incorporation of /sup 3/H thymidine by PBM cells in vitro. However, cells in the prereplicative compartment of the cell cycle (G0/1 cells) had significantly lower RNA content within 7 days of treatment with high doses of steroids. The results suggest that steroids do not acutely influence the posttranscriptional synthesis and the contents of nucleic acids of cells undergoing clonal expansion in vivo. The prereplicative phase of allogeneically stimulated PBM cells of renal allograft recipients may therefore be the cell cycle phase most sensitive to steroids in vivo.

  11. Transgenic expression of CD95 ligand on thyroid follicular cells confers immune privilege upon thyroid allografts.

    Science.gov (United States)

    Tourneur, L; Malassagne, B; Batteux, F; Fabre, M; Mistou, S; Lallemand, E; Lores, P; Chiocchia, G

    2001-08-01

    Constitutive Fas ligand (FasL) expression by specialized cells in the body participates in the immune privilege status of tissues containing these cells. This property has been used to prevent rejection of allogeneic grafts. Nevertheless, the mechanism responsible for such protection has not been fully elucidated. Unfortunately, grafting of FasL transgenic (TG) tissues has been unsuccessful. We have generated TG mice expressing FasL (soluble + membrane bound) on thyroid follicular cells (TFC), and used them to show that ectopic FasL expression prevents thyroid allograft rejection. FasL expression on TFC led to markedly decreased anti-allogeneic, cytotoxic, and helper T lymphocyte activities. The alloantibody response in TG thyroid recipients was either completely inhibited or switched toward a T2-Ab response. Surprisingly, the beneficial effect of FasL on TG thyroid grafts was abolished by host CD4(+) T cell depletion. Host CD8(+) T cell depletion improved nontransgenic (NTG), but not TG graft survival. Altogether, our results suggest that FasL-induced tolerance is concomitant with a move away from a T1 type response, and a CD4 T cell-mediated regulation of the allocytotoxic T cell response. These results were dependent upon the level of FasL expression on TFC, in that low expression of FasL led to a less marked effect compared with the effect observed with high expression of FasL. These results provide some insight into the role of FasL in regulating destructive alloimmune responses in the case of whole organ grafting, and they have important implications for the development of FasL-based immunotherapy in organ transplantation.

  12. Host-derived smooth muscle cells accumulate in cardiac allografts: role of inflammation and monocyte chemoattractant protein 1.

    Directory of Open Access Journals (Sweden)

    Piotr Religa

    Full Text Available Transplant arteriosclerosis is characterized by inflammation and intimal thickening caused by accumulation of smooth muscle cells (SMCs both from donor and recipient. We assessed the relationship between clinical factors and the presence of host-derived SMCs in 124 myocardial biopsies from 26 consecutive patients who received hearts from opposite-sex donors. Clinical and demographic information was obtained from the patients' medical records. Host-derived SMCs accounted for 3.35+/-2.3% of cells in arterioles (range, 0.08-12.51%. As shown by linear regression analysis, an increased number of SMCs was associated with rejection grade (mean, 1.41+/-1.03, p = 0.034 and the number of leukocytes (19.1+/-12.7 per 20 high-power fields, p = 0.01. The accumulation of host-derived SMCs was associated with an increased number of leukocytes in the allografts. In vitro, monocyte chemoattractant protein 1 (MCP-1 released from leukocytes was crucial for SMC migration. After heart allotransplantation, mice treated with MCP-1-specific antibodies had significantly fewer host-derived SMCs in the grafts than mice treated with isotypic antibody controls. We conclude that the number of host-derived SMCs in human cardiac allografts is associated with the rejection grade and that MCP-1 may play pivotal role in recruiting host-derived SMCs into cardiac allografts.

  13. Host-Derived Smooth Muscle Cells Accumulate in Cardiac Allografts: Role of Inflammation and Monocyte Chemoattractant Protein 1

    Science.gov (United States)

    Bojakowski, Krzysztof; Soin, Joanna; Nozynski, Jerzy; Zakliczynski, Michal; Gaciong, Zbigniew; Zembala, Marian; Söderberg-Nauclér, Cecilia

    2009-01-01

    Transplant arteriosclerosis is characterized by inflammation and intimal thickening caused by accumulation of smooth muscle cells (SMCs) both from donor and recipient. We assessed the relationship between clinical factors and the presence of host-derived SMCs in 124 myocardial biopsies from 26 consecutive patients who received hearts from opposite-sex donors. Clinical and demographic information was obtained from the patients' medical records. Host-derived SMCs accounted for 3.35±2.3% of cells in arterioles (range, 0.08–12.51%). As shown by linear regression analysis, an increased number of SMCs was associated with rejection grade (mean, 1.41±1.03, p = 0.034) and the number of leukocytes (19.1±12.7 per 20 high-power fields, p = 0.01). The accumulation of host-derived SMCs was associated with an increased number of leukocytes in the allografts. In vitro, monocyte chemoattractant protein 1 (MCP-1) released from leukocytes was crucial for SMC migration. After heart allotransplantion, mice treated with MCP-1-specific antibodies had significantly fewer host-derived SMCs in the grafts than mice treated with isotypic antibody controls. We conclude that the number of host-derived SMCs in human cardiac allografts is associated with the rejection grade and that MCP-1 may play pivotal role in recruiting host-derived SMCs into cardiac allografts. PMID:19142231

  14. The amelioration of composite tissue allograft rejection by TIM-3-modified dendritic cell: Regulation of the balance of regulatory and effector T cells.

    Science.gov (United States)

    Wang, Yaojun; Zheng, Zhao; Zhu, Xiongxiang; Han, Juntao; Dong, Maolong; Tao, Ke; Wang, Hongtao; Wang, Yunchuan; Hu, Dahai

    2016-01-01

    T cell-dependent immune responses play a central role in allograft rejection. Exploring ways to disarm alloreactive T cells represents a potential strategy to promote long-term allograft acceptance and survival. T cell Ig domain and mucin domain 3 (TIM-3) has previously been demonstrated as a central regulator of T helper 1 (Th1) responses and immune tolerance. Hence, TIM-3 may be an important molecule for decreasing immunological rejection during composite tissue allotransplantation (CTA). In this study, BALB/c and C57BL/6 mice were chosen as the experimental animals. The effects of TIM-3 on allograft rejection were explored using TIM-3-modified mature dendritic cells (TIM-3 mDCs). A laser speckle blood flow (LSBF) imager was used to evaluate blood distribution of the BALB/c mice. ELISA, MTT, ELISPOT assays and flow cytometry analysis were carried out for further researches. We found that TIM-3 could obviously prolong the survival time of the transplanted limbs. And TIM-3 could mitigate the immune response and thus enhance immune tolerance after CTA. Also, TIM-3 can induce lymphocyte hyporesponsiveness, including facilitating lymphocyte apoptosis, decreasing lymphocyte proliferation, and influencing the secretion of inflammatory cytokines by CD4(+) T cells. Furthermore, TIM-3 overexpression could induce CD4(+) T cells to differentiate into regulatory T cells (Tregs), which recalibrate the effector and regulatory arms of the alloimmune response. In summary, we concluded that TIM-3 can mitigate allograft rejection and thus enhance immune tolerance by inducing lymphocyte hyporesponsiveness and increasing the number of Tregs of the alloimmune response. TIM-3 may be a potential therapeutic molecule for allograft rejection in CTA.

  15. Protection against bronchiolitis obliterans syndrome is associated with allograft CCR7+ CD45RA- T regulatory cells.

    Directory of Open Access Journals (Sweden)

    Aric L Gregson

    Full Text Available Bronchiolitis obliterans syndrome (BOS is the major obstacle to long-term survival after lung transplantation, yet markers for early detection and intervention are currently lacking. Given the role of regulatory T cells (Treg in modulation of immunity, we hypothesized that frequencies of Treg in bronchoalveolar lavage fluid (BALF after lung transplantation would predict subsequent development of BOS. Seventy BALF specimens obtained from 47 lung transplant recipients were analyzed for Treg lymphocyte subsets by flow cytometry, in parallel with ELISA measurements of chemokines. Allograft biopsy tissue was stained for chemokines of interest. Treg were essentially all CD45RA(-, and total Treg frequency did not correlate to BOS outcome. The majority of Treg were CCR4(+ and CD103(- and neither of these subsets correlated to risk for BOS. In contrast, higher percentages of CCR7(+ Treg correlated to reduced risk of BOS. Additionally, the CCR7 ligand CCL21 correlated with CCR7(+ Treg frequency and inversely with BOS. Higher frequencies of CCR7(+ CD3(+CD4(+CD25(hiFoxp3(+CD45RA(- lymphocytes in lung allografts is associated with protection against subsequent development of BOS, suggesting that this subset of putative Treg may down-modulate alloimmunity. CCL21 may be pivotal for the recruitment of this distinct subset to the lung allograft and thereby decrease the risk for chronic rejection.

  16. Chromophobe renal cell carcinoma occurring in the renal allograft of a transplant recipient presenting with weight loss

    Directory of Open Access Journals (Sweden)

    Mohammed Mahdi Althaf

    2016-01-01

    Full Text Available The incidence of renal cell carcinomas (RCCs in renal transplant recipients is reported as 1.1-1.5% in the native kidneys and 0.22-0.25% in the renal allograft. There are no data to support routine surveillance for tumors in transplant recipients. Most reported cases of RCCs occurring in renal allografts were incidental findings in asymptomatic patients. Herein, we report the second case of lone chromophobe RCC (ChRCC of the renal allograft presenting with weight loss. Loss of weight is a presenting symptom in one-third of ChRCCs occurring in the native kidneys in the general population. Based on the age of the patient, R.E.N.A.L nephrometry score of the tumor and the lack of data on the prognosis of this histological subtype in a climate of long-term immunosuppression, we elected for radical nephrectomy. We suggest that RCCs should be considered in the differential diagnosis of a transplant recipient presenting with weight loss even in the absence of localizing symptoms or signs.

  17. Chromophobe renal cell carcinoma occurring in the renal allograft of a transplant recipient presenting with weight loss.

    Science.gov (United States)

    Althaf, Mohammed Mahdi; Al-Sunaid, Mohammed S; Abdelsalam, Mohamed Said; Alkorbi, Lutfi A; Al-Hussain, Turki O; Dababo, Mohammed Anas; Haq, Naveed

    2016-01-01

    The incidence of renal cell carcinomas (RCCs) in renal transplant recipients is reported as 1.1-1.5% in the native kidneys and 0.22-0.25% in the renal allograft. There are no data to support routine surveillance for tumors in transplant recipients. Most reported cases of RCCs occurring in renal allografts were incidental findings in asymptomatic patients. Herein, we report the second case of lone chromophobe RCC (ChRCC) of the renal allograft presenting with weight loss. Loss of weight is a presenting symptom in one-third of ChRCCs occurring in the native kidneys in the general population. Based on the age of the patient, R.E.N.A.L nephrometry score of the tumor and the lack of data on the prognosis of this histological subtype in a climate of long-term immunosuppression, we elected for radical nephrectomy. We suggest that RCCs should be considered in the differential diagnosis of a transplant recipient presenting with weight loss even in the absence of localizing symptoms or signs.

  18. A novel, blocking, Fc-silent anti-CD40 monoclonal antibody prolongs nonhuman primate renal allograft survival in the absence of B cell depletion.

    Science.gov (United States)

    Cordoba, F; Wieczorek, G; Audet, M; Roth, L; Schneider, M A; Kunkler, A; Stuber, N; Erard, M; Ceci, M; Baumgartner, R; Apolloni, R; Cattini, A; Robert, G; Ristig, D; Munz, J; Haeberli, L; Grau, R; Sickert, D; Heusser, C; Espie, P; Bruns, C; Patel, D; Rush, J S

    2015-11-01

    CD40-CD154 pathway blockade prolongs renal allograft survival in nonhuman primates (NHPs). However, antibodies targeting CD154 were associated with an increased incidence of thromboembolic complications. Antibodies targeting CD40 prolong renal allograft survival in NHPs without thromboembolic events but with accompanying B cell depletion, raising the question of the relative contribution of B cell depletion to the efficacy of anti-CD40 blockade. Here, we investigated whether fully silencing Fc effector functions of an anti-CD40 antibody can still promote graft survival. The parent anti-CD40 monoclonal antibody HCD122 prolonged allograft survival in MHC-mismatched cynomolgus monkey renal allograft transplantation (52, 22, and 24 days) with accompanying B cell depletion. Fc-silencing yielded CFZ533, an antibody incapable of B cell depletion but still able to potently inhibit CD40 pathway activation. CFZ533 prolonged allograft survival and function up to a defined protocol endpoint of 98-100 days (100, 100, 100, 98, and 76 days) in the absence of B cell depletion and preservation of good histological graft morphology. CFZ533 was well-tolerated, with no evidence of thromboembolic events or CD40 pathway activation and suppressed a gene signature associated with acute rejection. Thus, use of the Fc-silent anti-CD40 antibody CFZ533 appears to be an attractive approach for preventing solid organ transplant rejection.

  19. Induction of Foxp3-expressing regulatory T-cells by donor blood transfusion is required for tolerance to rat liver allografts.

    Directory of Open Access Journals (Sweden)

    Yuta Abe

    Full Text Available BACKGROUND: Donor-specific blood transfusion (DST prior to solid organ transplantation has been shown to induce long-term allograft survival in the absence of immunosuppressive therapy. Although the mechanisms underlying DST-induced allograft tolerance are not well defined, there is evidence to suggest DST induces one or more populations of antigen-specific regulatory cells that suppress allograft rejection. However, neither the identity nor the regulatory properties of these tolerogenic lymphocytes have been reported. Therefore, the objective of this study was to define the kinetics, phenotype and suppressive function of the regulatory cells induced by DST alone or in combination with liver allograft transplantation (LTx. METHODOLOGY/PRINCIPAL FINDINGS: Tolerance to Dark Agouti (DA; RT1(a rat liver allografts was induced by injection (iv of 1 ml of heparinized DA blood to naïve Lewis (LEW; RT1(l rats once per week for 4 weeks prior to LTx. We found that preoperative DST alone generates CD4(+ T-cells that when transferred into naïve LEW recipients are capable of suppressing DA liver allograft rejection and promoting long-term survival of the graft and recipient. However, these DST-generated T-cells did not express the regulatory T-cell (Treg transcription factor Foxp3 nor did they suppress alloantigen (DA-induced activation of LEW T-cells in vitro suggesting that these lymphocytes are not fully functional regulatory Tregs. We did observe that DST+LTx (but not DST alone induced the time-dependent formation of CD4(+Foxp3(+ Tregs that potently suppressed alloantigen-induced activation of naïve LEW T-cells in vitro and liver allograft rejection in vivo. Finally, we present data demonstrating that virtually all of the Foxp3-expressing Tregs reside within the CD4(+CD45RC(- population whereas in which approximately 50% of these Tregs express CD25. CONCLUSIONS/SIGNIFICANCE: We conclude that preoperative DST, in the absence of liver allograft

  20. Lymphoid-Like Structures with Distinct B Cell Areas in Kidney Allografts are not Predictive for Graft Rejection. A Non-human Primate Study

    NARCIS (Netherlands)

    Jonker, Margreet; Wubben, Jacqueline A. M.; 't Hart, Bert A.; Haanstra, Krista G.

    2015-01-01

    Kidney allograft biopsies were analyzed for the presence of B cell clusters/aggregates using CD20 staining. Few B cells were found in the diffuse interstitial infiltrates, but clusters of B cells were found in nodular infiltrates. These nodular infiltrates were smaller shortly after transplantation,

  1. Plasma cell-rich acute rejection of the renal allograft: A distinctive morphologic form of acute rejection?

    Science.gov (United States)

    Gupta, R; Sharma, A; Mahanta, P J; Agarwal, S K; Dinda, A K

    2012-05-01

    This study was aimed at evaluating the clinicopathologic features of plasma cell-rich acute rejection (PCAR) of renal allograft and comparing them with acute cellular rejection (ACR), non-plasma cell-rich type. During a 2-year period, eight renal allograft biopsies were diagnosed as PCAR (plasma cells >10% of interstitial infiltrate). For comparison, 14 biopsies with ACR were included in the study. Detailed pretransplant data, serum creatinine at presentation, and other clinical features of all these cases were noted. Renal biopsy slides were reviewed and relevant immunohistochemistry performed for characterization of plasma cell infiltrate. The age range and duration of transplantation to diagnosis of acute rejection were comparable in both the groups. Histologically, the proportion of interstitial plasma cells, mean interstitial inflammation, and tubulitis score were higher in the PCAR group compared with cases with ACR. A significant difference was found in the outcome at last follow-up, being worse in patients with PCAR. This study shows that PCAR portends a poor outcome compared with ACR, with comparable Banff grade of rejection. Due to its rarity and recent description, nephrologists and renal pathologists need to be aware of this entity.

  2. Statins induce immunosuppressive effect on heterotopic limb allografts in rat through inhibiting T cell activation and proliferation.

    Science.gov (United States)

    Nie, Chunlei; Yang, Daping; Liu, Guofeng; Dong, Deli; Ma, Zhiqiang; Fu, Hailiang; Zhao, Zhengyu; Sun, Zhiyong

    2009-01-05

    Long-term use of immunosuppressive agents could bring many side effects. Recently, 3-Hydroxy-3-methyl-gutaryl coenzyme A reductase inhibitors (statins) have been reported to be immunomodulatory besides lowering serum cholesterol level. The aim of this study was to investigate the effects of statins on composite tissue allografts and T lymphocyte in vivo and in vitro. Rats were divided into 5 groups: syngeneic transplantation group (Lewis-Lewis); allogeneic control group (Brown Norway-Lewis, no treatment); low-dose statins group (15 mg /kg); high-dose statins group (30 mg /kg) and cyclosporin A group. In vivo, treatment of statins significantly prolonged allografts survival as compared to control group. Histological findings further supported these clinical results and demonstrated less extent of rejection. Immunohistochemical analysis showed that there was a remarkably reduced T cells infiltration in statins groups. Moreover, the serum levels of IL-2 and IFN-gamma were decreased after statins therapy, while these in control group increased significantly. Meanwhile, transcriptional activities of IL-2 and IFN-gamma were also dramatically down-regulated after statins treatment. In vitro, mixed lymphocyte reaction assay was performed and the results revealed lymphocyte proliferation was inhibited by statins in a dose-dependent manner. Furthermore, administration of statins exhibited inhibitory effects on CD3/CD28 mediated T cell activation and proliferation. Besides, the results demonstrated that statins significantly down-regulated mRNA expression and suppress cytokine production of IL-2 and IFN-gamma in vitro. In conclusion, our data demonstrated that application of statins could induce immunosuppressive effect and prolong allografts survival through inhibiting activation and proliferation of T cell and reducing production of IL-2 and IFN-gamma.

  3. Interleukin-12 (IL-12p70 promotes induction of highly potent Th1-like CD4+CD25+T regulatory cells that inhibit allograft rejection in unmodified recipients.

    Directory of Open Access Journals (Sweden)

    Nirupama Darshan Verma

    2014-05-01

    Full Text Available In rat models, CD4+CD25+T regulatory cells (Treg play a key role in the induction and maintenance of antigen specific transplant tolerance, especially in DA rats with PVG cardiac allografts(1, 2. We have previously described generation of alloantigen specific Treg (Ts1, by culture of naïve natural CD4+CD25+ Treg (nTreg with specific alloantigen and IL-2 for 4 days. These cells express mRNA for IFN-γ receptor (ifngr and suppress donor but not third party cardiac allograft rejection mediated by alloreactive CD4+T cells at ratios of We induced highly suppressive Th1-like Treg from naïve nTreg in 7 days by culture with alloantigen, first with rIL-2 then with rIL-12p70. These Th1-like Treg delayed specific-donor allograft rejection demonstrating therapeutic potential

  4. Down-regulating cyclin-dependent kinase 9 of alloreactive CD4+ T cells prolongs allograft survival

    Science.gov (United States)

    Zhan, Yang; Han, Yeming; Sun, Hukui; Liang, Ting; Zhang, Chao; Song, Jing; Hou, Guihua

    2016-01-01

    CDK9 (Cyclin-dependent kinase 9)/Cyclin T1/RNA polymerase II pathway has been demonstrated to promote the development of several inflammatory diseases, such as arthritis or atherosclerosis, however, its roles in allotransplantation rejection have not been addressed. Here, we found that CDK9/Cyclin T1 were apparently up-regulated in the allogeneic group, which was positively correlated with allograft damage. CDK9 was inhibited obviously in naive splenic CD4+ T cells treated 6 h with 3 μM PHA767491 (a CDK9 inhibitor), and adoptive transfer of these CD4+ T cells into allografted SCID mice resulted in prolonged survival compared with the group without PHA767491 pretreated. Decelerated rejection was correlated with enhanced IL-4 and IL-10 production and with decreased IFN-γ production by alloreactive T cells. More interestingly, we found that CDK942, not CDK955, was high expressed in allorejection group, which could be prominently dampened with PHA767491 treatment. The expression of CDK942 was consistent with its downstream molecule RNA polymerase II. Altogether, our findings revealed the crucial role of CDK9/Cyclin T1/Pol II pathway in promoting allorejection at multiple levels and may provide a new approach for transplantation tolerance induction through targeting CDK9. PMID:27102157

  5. Abrogation of the immunosuppressive effect of donor spleen cells on renal allografts in the rat by irradiation or heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Cranston, D.; Wood, K.J.; Morris, P.J.

    1986-09-01

    In the donor-recipient strain combination Lewis (RT1l) to Dark Agouti (RT1a), indefinite renal allograft survival (MST greater than 100 days) was induced by pretreating recipient animals i.v. with 10(6) to 10(8) viable spleen lymphocytes, seven days before transplantation. Pretreatment with 10(4) or 10(5) cells was ineffective (MST 10 days). However when 10(7) live, but heat-treated (55 degrees C for 10 min) or irradiated (1000 rads) cells were used, all the animals rejected the allograft in a normal fashion (MST 10 and 11 days, respectively). Median survival time of third-party controls was 10 days. The relative amount of cell surface major histocompatibility antigens (class I and class II) expressed by the three spleen cell preparations was investigated using monoclonal antibodies and fluorescence activated cell sorter analysis and found to be similar. After 24 hr in culture, only 1% of heat-treated and 10% of irradiated cells were viable, in contrast to 75% of untreated splenocytes. Trafficking of these lymphocytes in recipient animals was investigated by 51chromium labeling of the cells: 30% of lymphocytes had localized in the liver within 3 hr with little difference in localization among the different cell preparations. But, although 20% of normal and irradiated cells localized in the spleen within 3 hr, at no stage were more than 5% of the heat-treated cells found in the spleen. It is suggested that the length of time viable donor lymphocytes remain in the recipient circulation is important in the induction of specific immunosuppression by spleen lymphocytes.

  6. Evaluation and optimization of silicon sheet solar cells

    Science.gov (United States)

    Yoo, H.; Iles, P.; Tanner, D.; Pollock, G.; Uno, F.

    1980-01-01

    This paper describes the results and procedures to evaluate and improve the efficiency of solar cells made from various unconventional silicon sheets. The performance parameters included photovoltaic characteristics, spectral response, dark I-V characteristics, and diffusion length. The evaluation techniques used provided accurate and reliable information on sheet performance, and self-consistent results were obtained from the various measurement techniques used. Minority carrier diffusion length (L) was shown to be the ultimate limiting factor for the sheet cell performance (efficiency) and other back-up measurements confirmed this L-dependence. Limited efforts were made to identify defects which influence cell performance, and to use some improved process methods to increase cell efficiency.

  7. Cell sheet technology for regeneration of esophageal mucosa

    Institute of Scientific and Technical Information of China (English)

    Ryo Takagi; Teruo Okano; Masayuki Yamato; Nobuo Kanai; Daisuke Murakami; Makoto Kondo; Takaaki Ishii; Takeshi Ohki; Hideo Namiki; Masakazu Yamamoto

    2012-01-01

    The progress of tissue-engineering technology has realized development of new therapies to treat various disorders by using cultured cells.Cell-and tissue-based therapies have been successfully applied to human patients,and several tissue-engineered products have been approved by the regulatory agencies and are commercially available.In the review article,we describe our experience of development and clinical application of cell sheet-based regenerative medicine.Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have been shown to be useful for removal of gastrointestinal neoplasms with less invasiveness compared with open surgery,especially in esophageal surgery.However,postoperative inflammation and stenosis are major complications observed after intensive mucosal resection.Therefore,we have developed novel regenerative medicine to prevent such complications and promote wound healing of esophageal mucosa after EMR or ESD.Transplantable oral mucosal epithelial cell sheets were fabricated from patients' own oral mucosa.Immediately after EMR or ESD,fabricated autologous cell sheets were endoscopically transplanted to the ulcer sites.We performed a preclinical study with a canine model.In human clinical settings,cell culture and cell sheet fabrication were performed in clean rooms according to good manufacturing practice guidelines,and pharmaceutical drugs were used as supplements to culture medium in place of research regents used in animal study.We believe that cell-based regenerative medicine would be useful to improve quality of life of patients after EMR or ESD.

  8. A novel closed cell culture device for fabrication of corneal epithelial cell sheets.

    Science.gov (United States)

    Nakajima, Ryota; Kobayashi, Toyoshige; Moriya, Noboru; Mizutani, Manabu; Kan, Kazutoshi; Nozaki, Takayuki; Saitoh, Kazuo; Yamato, Masayuki; Okano, Teruo; Takeda, Shizu

    2015-11-01

    Automation technology for cell sheet-based tissue engineering would need to optimize the cell sheet fabrication process, stabilize cell sheet quality and reduce biological contamination risks. Biological contamination must be avoided in clinical settings. A closed culture system provides a solution for this. In the present study, we developed a closed culture device called a cell cartridge, to be used in a closed cell culture system for fabricating corneal epithelial cell sheets. Rabbit limbal epithelial cells were cultured on the surface of a porous membrane with 3T3 feeder cells, which are separate from the epithelial cells in the cell cartridges and in the cell-culture inserts as a control. To fabricate the stratified cell sheets, five different thicknesses of the membranes which were welded to the cell cartridge, were examined. Multilayered corneal epithelial cell sheets were fabricated in cell cartridges that were welded to a 25 µm-thick gas-permeable membrane, which was similar to the results with the cell-culture inserts. However, stratification of corneal epithelial cell sheets did not occur with cell cartridges that were welded to 100-300 µm-thick gas-permeable membranes. The fabricated cell sheets were evaluated by histological analyses to examine the expression of corneal epithelial-specific markers. Immunohistochemical analyses showed that a putative stem cell marker, p63, a corneal epithelial differentiation maker, CK3, and a barrier function marker, Claudin-1, were expressed in the appropriate position in the cell sheets. These results suggest that the cell cartridge is effective for fabricating corneal epithelial cell sheets.

  9. The number of regulatory T cells in transbronchial lung allograft biopsies is related to FoxP3 mRNA levels in bronchoalveolar lavage fluid and to the degree of acute cellular rejection

    DEFF Research Database (Denmark)

    Krustrup, Dorrit; Madsen, Caroline B; Iversen, Martin;

    2013-01-01

    The transcription factor Forkhead Box P3 (FoxP3) is a marker of regulatory T cells (Tregs) - a subset of T cells known to suppress a wide range of immune responses. These cells are considered to be pivotal for the induction of tolerance to donor antigens in human allografts. We aimed to correlate...... the number of lymphocytes expressing FoxP3 in transbronchial biopsies from lung allografts with the FoxP3 expression in bronchoalveolar lavage fluid (BALF). In addition, we aimed to correlate the number of FoxP3+ cells in transbronchial biopsies with the degree of acute cellular rejection in lung allografts....

  10. The synergistic immunoregulatory effects of culture-expanded mesenchymal stromal cells and CD4(+25(+Foxp3+ regulatory T cells on skin allograft rejection.

    Directory of Open Access Journals (Sweden)

    Jung Ho Lee

    Full Text Available Mesenchymal stromal cells (MSCs are seen as an ideal source of cells to induce graft acceptance; however, some reports have shown that MSCs can be immunogenic rather than immunosuppressive. We speculate that the immunomodulatory effects of regulatory T cells (Tregs can aid the maintenance of immunoregulatory functions of MSCs, and that a combinatorial approach to cell therapy can have synergistic immunomodulatory effects on allograft rejection. After preconditioning with Fludarabine, followed by total body irradiation and anti-asialo-GM-1(ASGM-1, tail skin grafts from C57BL/6 (H-2k(b mice were grafted onto the lateral thoracic wall of BALB/c (H-2k(d mice. Group A mice (control group, n = 9 did not receive any further treatment after preconditioning, whereas groups B and C (n = 9 received cell therapy with MSCs or Tregs, respectively, on days -1, +6 and +13 relative to the skin transplantation. Group D (n = 10 received cell therapy with MSCs and Tregs on days -1, +6 and +13. Cell suspensions were obtained from the spleens of five randomly chosen mice from each group on day +7, and the immunomodulatory effects of the cell therapy were evaluated by flow cytometry and real-time PCR. Our results show that allograft survival was significantly longer in group D compared to the control group (group A. Flow cytometric analysis and real-time PCR for splenocytes revealed that the Th2 subpopulation in group D increased significantly compared to the group B. Also, the expression of Foxp3 and STAT 5 increased significantly in group D compared to the conventional cell therapy groups (B and C. Taken together, these data suggest that a combined cell therapy approach with MSCs and Tregs has a synergistic effect on immunoregulatory function in vivo, and might provide a novel strategy for improving survival in allograft transplantation.

  11. Intelligent thermoresponsive substrate from modified overhead projection sheet as a tool for construction and support of cell sheets in vitro.

    Science.gov (United States)

    Nithya, Joseph; Kumar, P R Anil; Tilak, Prasad; Leena, Joseph; Sreenivasan, K; Kumary, T V

    2011-02-01

    Cell sheet engineering using thermoresponsive culture dishes allows harvesting of intact in vitro cell sheet. In this study, commercially available polyethylene terephthalate-based overhead projection transparency sheet (OHPS) was identified as a substrate for coating thermoresponsive poly(N-isopropylacrylamide-co-glycidylmethacrylate) (NGMA) copolymer having lower critical solution temperature of 28°C. Since OHPS is highly hydrophobic and rigid, the surface was modified by alkali treatment (OHPS-M) to functionalize the surface with carboxyl and hydroxyl groups so as to make it more suitable for efficient coating of NGMA copolymer and cell culture. To impart thermoresponsiveness, OHPS-M was coated with NGMA (OHPS-MC). Surface morphology, surface chemistry, and thermoresponsive coating were analyzed by profilometry, scanning electron microscopy, water contact angle, and Fourier transform infrared spectroscopy. The cytotoxicity, cell adhesion, and proliferation on OHPS-M and OHPS-MC were analyzed using L929 cells. Specific cytocompatibility analysis was done using SIRC (Rabbit corneal) cells. Data revealed cytocompatible nature of OHPS-M and OHPS-MC. Suitability of OHPS-MC for cell sheet harvest and transfer efficiency was assessed using primary corneal cells. Corneal cell sheet constructs retrieved by temperature variation was characterized by reverse transcriptase polymerase chain reaction for markers specific to differentiated corneal cells (keratin 3 and keratin 12) and proliferating cell nuclear antigen, and assessed for viability using fluorescein diacetate staining, tissue architecture by scanning electron microscopy, and cell-cell contacts by connexin-43 staining. The retrieved cell sheets retained corneal epithelial characteristics such as keratin 3/12, viability, and tissue architecture with intact cell-cell contacts as in native tissue. The results proved that surface modification and coating with NGMA on OHPS offer a novel biocompatible thermosensitive

  12. Combining Exosomes Derived from Immature DCs with Donor Antigen-Specific Treg Cells Induces Tolerance in a Rat Liver Allograft Model

    Science.gov (United States)

    Ma, Ben; Yang, Jing-Yue; Song, Wen-jie; Ding, Rui; Zhang, Zhuo-chao; Ji, Hong-chen; Zhang, Xuan; Wang, Jian-lin; Yang, Xi-sheng; Tao, Kai-shan; Dou, Ke-feng; Li, Xiao

    2016-01-01

    Allograft tolerance is the ultimate goal in the field of transplantation immunology. Immature dendritic cells (imDCs) play an important role in establishing tolerance but have limitations, including potential for maturation, short lifespan in vivo and short storage times in vitro. However, exosomes (generally 30–100 nm) from imDCs (imDex) retain many source cell properties and may overcome these limitations. In previous reports, imDex prolonged the survival time of heart or intestine allografts. However, tolerance or long-term survival was not achieved unless immune suppressants were used. Regulatory T cells (Tregs) can protect allografts from immune rejection, and our previous study showed that the effects of imDex were significantly associated with Tregs. Therefore, we incorporated Tregs into the treatment protocol to further reduce or avoid suppressant use. We defined the optimal exosome dose as approximately 20 μg (per treatment before, during and after transplantation) in rat liver transplantation and the antigen-specific role of Tregs in protecting liver allografts. In the co-treatment group, recipients achieved long-term survival, and tolerance was induced. Moreover, imDex amplified Tregs, which required recipient DCs and were enhanced by IL-2. Fortunately, the expanded Tregs retained their regulatory ability and donor-specificity. Thus, imDex and donor-specific Tregs can collaboratively induce graft tolerance. PMID:27640806

  13. The Presence of HLA-E-Restricted, CMV-Specific CD8+ T Cells in the Blood of Lung Transplant Recipients Correlates with Chronic Allograft Rejection.

    Directory of Open Access Journals (Sweden)

    Lucy C Sullivan

    Full Text Available The human cytomegalovirus (CMV immune evasion protein, UL40, shares an identical peptide sequence with that found in the leader sequence of many human leukocyte antigen (HLA-C alleles and when complexed with HLA-E, can modulate NK cell functions via interactions with the CD94-NKG2 receptors. However the UL40-derived sequence can also be immunogenic, eliciting robust CD8+ T cell responses. In the setting of solid organ transplantation these T cells may not only be involved in antiviral immunity but also can potentially contribute to allograft rejection when the UL40 epitope is also present in allograft-encoded HLA. Here we assessed 15 bilateral lung transplant recipients for the presence of HLA-E-restricted UL40 specific T cells by tetramer staining of peripheral blood mononuclear cells (PBMC. UL40-specific T cells were observed in 7 patients post-transplant however the magnitude of the response varied significantly between patients. Moreover, unlike healthy CMV seropositive individuals, longitudinal analyses revealed that proportions of such T cells fluctuated markedly. Nine patients experienced low-grade acute cellular rejection, of which 6 also demonstrated UL40-specific T cells. Furthermore, the presence of UL40-specific CD8+ T cells in the blood was significantly associated with allograft dysfunction, which manifested as Bronchiolitis Obliterans Syndrome (BOS. Therefore, this study suggests that minor histocompatibility antigens presented by HLA-E can represent an additional risk factor following lung transplantation.

  14. Total allograft transplantation of the elbow joint after wide resection of synovial cell sarcoma: a case series.

    Science.gov (United States)

    Hossein, E M; Ashraf, H; Peivandi, L

    2011-03-01

    Total elbow allograft transplantation is an option for patients who have extensive joint defects secondary to tumor surgery, trauma, or failed total elbow arthroplasty. This salvage procedure provides patients with a useful, painless range of motion of the elbow. We report our experience with two complete elbow allograft reconstructions after tumor resection surgery with 5 and 6 years of follow-up.

  15. Precisely Assembled Nanofiber Arrays as a Platform to Engineer Aligned Cell Sheets for Biofabrication

    Directory of Open Access Journals (Sweden)

    Vince Beachley

    2014-08-01

    Full Text Available A hybrid cell sheet engineering approach was developed using ultra-thin nanofiber arrays to host the formation of composite nanofiber/cell sheets. It was found that confluent aligned cell sheets could grow on uniaxially-aligned and crisscrossed nanofiber arrays with extremely low fiber densities. The porosity of the nanofiber sheets was sufficient to allow aligned linear myotube formation from differentiated myoblasts on both sides of the nanofiber sheets, in spite of single-side cell seeding. The nanofiber content of the composite cell sheets is minimized to reduce the hindrance to cell migration, cell-cell contacts, mass transport, as well as the foreign body response or inflammatory response associated with the biomaterial. Even at extremely low densities, the nanofiber component significantly enhanced the stability and mechanical properties of the composite cell sheets. In addition, the aligned nanofiber arrays imparted excellent handling properties to the composite cell sheets, which allowed easy processing into more complex, thick 3D structures of higher hierarchy. Aligned nanofiber array-based composite cell sheet engineering combines several advantages of material-free cell sheet engineering and polymer scaffold-based cell sheet engineering; and it represents a new direction in aligned cell sheet engineering for a multitude of tissue engineering applications.

  16. Auditory stimulation of opera music induced prolongation of murine cardiac allograft survival and maintained generation of regulatory CD4+CD25+ cells

    Directory of Open Access Journals (Sweden)

    Uchiyama Masateru

    2012-03-01

    Full Text Available Abstract Background Interactions between the immune response and brain functions such as olfactory, auditory, and visual sensations are likely. This study investigated the effect of sounds on alloimmune responses in a murine model of cardiac allograft transplantation. Methods Naïve CBA mice (H2k underwent transplantation of a C57BL/6 (B6, H2b heart and were exposed to one of three types of music--opera (La Traviata, classical (Mozart, and New Age (Enya--or one of six different single sound frequencies, for 7 days. Additionally, we prepared two groups of CBA recipients with tympanic membrane perforation exposed to opera for 7 days and CBA recipients exposed to opera for 7 days before transplantation (pre-treatment. An adoptive transfer study was performed to determine whether regulatory cells were generated in allograft recipients. Immunohistochemical, cell-proliferation, cytokine, and flow cytometry assessments were also performed. Results CBA recipients of a B6 cardiac graft that were exposed to opera music and Mozart had significantly prolonged allograft survival (median survival times [MSTs], 26.5 and 20 days, respectively, whereas those exposed to a single sound frequency (100, 500, 1000, 5000, 10,000, or 20,000 Hz or Enya did not (MSTs, 7.5, 8, 9, 8, 7.5, 8.5 and 11 days, respectively. Untreated, CBA mice with tympanic membrane perforations and CBA recipients exposed to opera for 7 days before transplantation (pre-treatment rejected B6 cardiac grafts acutely (MSTs, 7, 8 and 8 days, respectively. Adoptive transfer of whole splenocytes, CD4+ cells, or CD4+CD25+ cells from opera-exposed primary allograft recipients resulted in significantly prolonged allograft survival in naive secondary recipients (MSTs, 36, 68, and > 100 days, respectively. Proliferation of splenocytes, interleukin (IL-2 and interferon (IFN-γ production was suppressed in opera-exposed mice, and production of IL-4 and IL-10 from opera-exposed transplant recipients increased

  17. Combined HLA matched limbal stem cells allograft with amniotic membrane transplantation as a prophylactic surgical procedure to prevent corneal graft rejection after penetrating keratoplasty: case report

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    Paolo Capozzi

    2014-09-01

    Full Text Available Purpose. To determine if the use of combined HLA matched limbal stem cells allograft with amniotic membrane transplantation (AMT is a safe and effective prophylactic surgical procedure to prevent corneal graft after penetrating keratoplasty (PK. Methods. We report the case of a 17 years old patient with a history of congenital glaucoma, trabeculectomy and multiple corneal graft rejections, presenting total limbal cell deficiency. To reduce the possibility of graft rejection in the left eye after a new PK, a two step procedure was performed. At first the patient underwent a combined HLA matched limbal stem cells allograft (LAT and AMT and then, 10 months later, a new PK. Results. During 12 months of follow-up, the corneal graft remained stable and smooth, with no sign of graft rejection. Conclusions. In our patient, the prophylactic use of LAT from HLA-matched donors and AMT before PK, may result in a better prognosis of corneal graft survival.

  18. Osteogenic Matrix Cell Sheets Facilitate Osteogenesis in Irradiated Rat Bone

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    Yoshinobu Uchihara

    2015-01-01

    Full Text Available Reconstruction of large bone defects after resection of malignant musculoskeletal tumors is a significant challenge in orthopedic surgery. Extracorporeal autogenous irradiated bone grafting is a treatment option for bone reconstruction. However, nonunion often occurs because the osteogenic capacity is lost by irradiation. In the present study, we established an autogenous irradiated bone graft model in the rat femur to assess whether osteogenic matrix cell sheets improve osteogenesis of the irradiated bone. Osteogenic matrix cell sheets were prepared from bone marrow-derived stromal cells and co-transplanted with irradiated bone. X-ray images at 4 weeks after transplantation showed bridging callus formation around the irradiated bone. Micro-computed tomography images at 12 weeks postoperatively showed abundant callus formation in the whole circumference of the irradiated bone. Histology showed bone union between the irradiated bone and host femur. Mechanical testing showed that the failure force at the irradiated bone site was significantly higher than in the control group. Our study indicates that osteogenic matrix cell sheet transplantation might be a powerful method to facilitate osteogenesis in irradiated bones, which may become a treatment option for reconstruction of bone defects after resection of malignant musculoskeletal tumors.

  19. Allograftic bone marrow-derived mesenchymal stem cells transplanted into heart infarcted model of rabbit to renovate infarcted heart

    Institute of Scientific and Technical Information of China (English)

    王建安; 李长岭; 樊友启; 何红; 孙勇

    2004-01-01

    Objective: To investigate the directed transplantation of allograftic bone marrow-derived mesenchymal stem cells (MSCs) in myocardial infarcted (MI) model rabbits. Materials and Methods: Rabbits were divided into 3 groups, heart infarcted model with MSCs transplanted treatment (MSCs group, n=12), heart infarcted model with PBS injection (control group, n=20), sham operation with PBS injection (sham group, n=l 7). MSCs labelled by BrdUrd were injected into the MI area of the MSCs group. The same volume of PBS was injected into the MI area of the control group and sham group. The mortality, LVIDd, LVIDs and LVEF Of the two groups were compared 4 weeks later. Tropomyosin inhibitory component (Tn I) and BrdUrd immunohistochemistry identified the engrafted cells 4 weeks after transplantation. Result: The mortality of the MSCs group was 16.7% (2/12), and remarkably lower than the control group's mortality [35% (7/20) (P<0.05)].Among the animals that survived for 4 weeks, the LVIDd and LVIDs of the MSCs group after operation were 1.17±0.21 cm and 0.74±0.13 cm, and remarkably lower than those of the model group, which were 1.64±0.14 cm and 1.19±0.12 cm (P<0.05); the LVEF of the MSCs group after operation was 63±6%, and remarkably higher than that of the model group,which was 53±6% (P<0.05). Among the 10 cases of animals that survived for 4 weeks in the MSCs group, in 8 cases (80%),the transplanted cells survived in the non MI, MI region and its periphery, and even farther away; part of them differentiated into cardiomyocytes; in 7 cases (70%), the transplanted cells participated in the formation of blood vessel tissue in the MI region. Conclusion: Transplanted allograftic MSCs can survive and differentiate into cardiomyocytes, form the blood vessels in the MI region. MSCs transplantation could improve the heart function after MI.

  20. Allograftic bone marrow-derived mesenchymal stem cells transplanted into heart infarcted model of rabbit to renovate infarcted heart

    Institute of Scientific and Technical Information of China (English)

    王建安; 李长岭; 樊友启; 何红; 孙勇

    2004-01-01

    Objective: To investigate the directed transplantation of allograftic bone marrow-derived mesenchymal stem cells (MSCs) in myocardial infarcted (MI) model rabbits. Materials and Methods: Rabbits were divided into 3 groups, heart infarcted model with MSCs transplanted treatment (MSCs group, n=12), heart infarcted model with PBS injection (control group, n=20), sham operation with PBS injection (sham group, n=17). MSCs labelled by BrdUrd were injected into the MI area of the MSCs group. The same volume of PBS was injected into the MI area of the control group and sham group. The mortality, LVIDd, LVIDs and LVEF of the two groups were compared 4 weeks later. Tropomyosin inhibitory component (Tn Ⅰ) and BrdUrd immunohistochemistry identified the engrafted cells 4 weeks after transplantation. Result: The mortality of the MSCs group was 16.7% (2/12), and remarkably lower than the control group's mortality [35% (7/20) (P<0.05)]. Among the animals that survived for 4 weeks, the LVIDd and LVIDs of the MSCs group after operation were 1.17±0.21cm and 0.74±0.13cm, and remarkably lower than those of the model group, which were 1.64±0.14cm and 1.19±0.12cm (P<0.05); the LVEF of the MSCs group after operation was 63±6%, and remarkably higher than that of the model group, which was 53±6% (P<0.05). Among the 10 cases of animals that survived for 4 weeks in the MSCs group, in 8 cases (80%), the transplanted cells survived in the non MI, MI region and its periphery, and even farther away; part of them differentiated into cardiomyocytes; in 7 cases (70%), the transplanted cells participated in the formation of blood vessel tissue in the MI region. Conclusion: Transplanted allograftic MSCs can survive and differentiate into cardiomyocytes, form the blood vessels in the MI region. MSCs transplantation could improve the heart function after MI.

  1. Negative association of donor age with CD34+ cell dose in mixture allografts of G-CSF-primed bone marrow and G-CSF-mobilized peripheral blood harvests

    Institute of Scientific and Technical Information of China (English)

    Li Yan; Chang Yingjun; Xu Lanping; Zhang Xiaohui; Huang Xiaojun

    2014-01-01

    Background The effects of donor characteristics on CD34+ cell dose remain controversial.Recently,we developed a novel haploidentical transplant protocol,in which mixture allografts of granulocyte colony-stimulating factor (G-CSF)-primed bone marrow (G-BM) and G-CSF-mobilized peripheral blood (G-PB) were used.The aim of this study was to investigate the effects of donor characteristics on CD34+ cell dose in mixture allografts of G-BM and G-PB.Methods A total of 162 healthy adult donors,who underwent bone marrow harvest and peripheral blood collection between January 2009 and November 2010 in Peking University People's Hospital,were prospectively investigated.G-CSF was administered subcutaneously at a dose of 5 μg/kg once a day for 5-6 consecutive days.Bone marrow and peripheral blood stem cells were harvested on the fourth day and fifth day,respectively.A final total CD34+ cell dose less than 2× 106 cells/kg recipient body weight was considered a poor mobilization.Results Of the 162 donors,31 (19.1%) did not attain this threshold.The obtained median CD34+ cell doses in bone marrow,peripheral blood,and mixture allografts were 0.83×106/kg,2.40×106/kg,and 3.47×106/kg,respectively.Multiple regression analysis showed that donor age had a significant negative effect on CD34+ cell dose in either G-BM,or G-PB,or mixture allografts of G-BM and G-PB.And a 1-year increase in age was associated with a 5.6% decrease in the odds of achieving mobilization cutoff.No significant correlation was found for donor gender,body mass index (BMI),and weight.Conclusion Donor age is the only factor among the four parameters,including age,gender,weight,and BMI,that influence CD34+ cell dose in mixture allografts of G-BM and G-PB,and younger donors should be chosen to obtain sufficient CD34+ cells for transplantation.

  2. Long-term follow-up of kidney allografts in patients with sickle cell hemoglobinopathy Transplante renal na anemia falciforme

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    João R. Friedrisch

    2003-06-01

    Full Text Available Although sickle cell anemia and sickle cell disease produce a variety of functional renal abnormalities they uncommonly cause end stage renal failure. Renal transplantation has been a successful alternative for the treatment of the rare terminal chronic renal failure with outcomes comparable with non-sickle recipients. This approach, however, has not been often described on patients with renal failure associated with SC hemoglobinopathy. Here we report the outcomes of two patients with chronic renal failure due to SC hemoglobinopathies who underwent renal transplantation. At the time of the transplantation they were both severely anemic and had frequent vasoocclosive pain crises. Both patients evolved with good allograft function, near normal hematological parameters, and very rare pain crisis, thirteen and eight years after transplant. These cases illustrate that terminal renal failure due to SC hemoglobinopathy can be successfully managed by renal transplantation and satisfactory long-term results are achievable not only in terms of renal allograft function but also of their hematological condition.Embora a anemia falciforme e as síndromes falciformes freqüentemente causem várias alterações funcionais renais, não é comum a insuficiência renal terminal. Nestes casos, o transplante renal é uma alternativa que se acompanha de resultados comparáveis aos obtidos em receptores sem hemoglobinopatias. Esta estratégia terapêutica tem sido, no entanto, pouco relatada para portadores de hemoglobinopatia SC. Este relato descreve a evolução de dois pacientes portadores de hemoglobinopatia SC que foram submetidos ao transplante renal. No momento do transplante ambos apresentavam severa anemia e crises dolorosas freqüentes. Os pacientes evoluíram com boa função do enxerto, parâmetros hematológicos quase normais e praticamente assintomáticos do ponto de vista da hemoglobinopatia, treze e oito anos após o transplante. Estes casos ilustram

  3. Influence of nanotopography on periodontal ligament stem cell functions and cell sheet based periodontal regeneration.

    Science.gov (United States)

    Gao, Hui; Li, Bei; Zhao, Lingzhou; Jin, Yan

    2015-01-01

    Periodontal regeneration is an important part of regenerative medicine, with great clinical significance; however, the effects of nanotopography on the functions of periodontal ligament (PDL) stem cells (PDLSCs) and on PDLSC sheet based periodontal regeneration have never been explored. Titania nanotubes (NTs) layered on titanium (Ti) provide a good platform to study this. In the current study, the influence of NTs of different tube size on the functions of PDLSCs was observed. Afterward, an ectopic implantation model using a Ti/cell sheets/hydroxyapatite (HA) complex was applied to study the effect of the NTs on cell sheet based periodontal regeneration. The NTs were able to enhance the initial PDLSC adhesion and spread, as well as collagen secretion. With the Ti/cell sheets/HA complex model, it was demonstrated that the PDLSC sheets were capable of regenerating the PDL tissue, when combined with bone marrow mesenchymal stem cell (BMSC) sheets and HA, without the need for extra soluble chemical cues. Simultaneously, the NTs improved the periodontal regeneration result of the ectopically implanted Ti/cell sheets/HA complex, giving rise to functionally aligned collagen fiber bundles. Specifically, much denser collagen fibers, with abundant blood vessels as well as cementum-like tissue on the Ti surface, which well-resembled the structure of natural PDL, were observed in the NT5 and NT10 sample groups. Our study provides the first evidence that the nanotopographical cues obviously influence the functions of PDLSCs and improve the PDLSC sheet based periodontal regeneration size dependently, which provides new insight to the periodontal regeneration. The Ti/cell sheets/HA complex may constitute a good model to predict the effect of biomaterials on periodontal regeneration.

  4. Mesenchymal Stromal Cell Therapy for Chronic Lung Allograft Dysfunction: Results of a First-in-Man Study.

    Science.gov (United States)

    Chambers, Daniel C; Enever, Debra; Lawrence, Sharon; Sturm, Marian J; Herrmann, Richard; Yerkovich, Stephanie; Musk, Michael; Hopkins, Peter M A

    2017-04-01

    Chronic lung transplant rejection (termed chronic lung allograft dysfunction [CLAD]) is the main impediment to long-term survival after lung transplantation. Bone marrow-derived mesenchymal stromal cells (MSCs) represent an attractive cell therapy in inflammatory diseases, including organ rejection, given their relative immune privilege and immunosuppressive and tolerogenic properties. Preclinical studies in models of obliterative bronchiolitis and human trials in graft versus host disease and renal transplantation suggest potential efficacy in CLAD. The purpose of this phase 1, single-arm study was to explore the feasibility and safety of intravenous delivery of allogeneic MSCs to patients with advanced CLAD. MSCs from unrelated donors were isolated from bone marrow, expanded and cryopreserved in a GMP-compliant facility. Patients had deteriorating CLAD and were bronchiolitis obliterans (BOS) grade ≥ 2 or grade 1 with risk factors for rapid progression. MSCs (2 x 10(6) cells per kilogram patient weight) were infused via a peripheral vein twice weekly for 2 weeks, with 52 weeks follow-up. Ten Patients (5 male, 8 bilateral, median [interquartile range] age 40 [30-59] years, 3 BOS2, 7 BOS3) participated. MSC treatment was well tolerated with all patients receiving the full dosing schedule without any procedure-related serious adverse events. The rate of decline in forced expiratory volume in one second slowed after the MSC infusions (120 ml/month preinfusion vs. 30 ml/month postinfusion, p = .08). Two patients died at 152 and 270 days post-MSC treatment, both from progressive CLAD. In conclusion, infusion of allogeneic bone marrow-derived MSCs is feasible and safe even in patients with advanced CLAD. Stem Cells Translational Medicine 2017;6:1152-1157.

  5. Allograft rejection-related gene expression in the endothelial cells of renal transplantation recipients after cytomegalovirus infection

    Institute of Scientific and Technical Information of China (English)

    Yang LI; Jun HOU; Hang YAN; Wu-jun XUE; Pu-xun TIAN; Xiao-ming DING; Xiao-ming PAN; Xin-shun FENG; Xiao-hui TIAN; He-li XIANG

    2009-01-01

    Objective: To explore the effects of cytomegalovirus (CMV) infection on rejection-related gene expression in the endothelial cells of renal transplantation recipients. Methods: Endothelial cells (ECs) were cultured and stimulated by a variety of factors: A, normal control group; B, inactivated human cytomegalovirus (HCMV) infection group; C, HCMV infection group; D, HCMV supematant infection group; and E, ganciclovir HCMV group. Expression of intercellular adhesion molecule-1 (ICAM-1) and major histocompability complex (MHC) class Ⅰ and class Ⅱ antigens was detected by flow cytometry (FCM) and immuno-histochemistry. Results: We found characteristic CMV-infected ECs in this study. There were no significant differences among groups A, B and D (P>0.05). Although the expression levels of ICAM-1 were not significantly different between groups C and E (P>0.05), the ICAM-1 expression in these two groups was significantly higher than that in group A (P0.05). Human leucocyte antigen (HLA)-ABC expression was detected in all the groups, while HLA-DR expression was only detected in groups C and E. There were no significant dif-ferences of HLA-ABC and HLA-DR expression among groups A, B and D (P>0.05). However, the HLA-ABC and HLA-DR expression levels in groups C and D were higher than those of the remaining groups previously reported (P<0.05). Meanwhile, the HLA-ABC and HLA-DR expression levels in group E were lower than those of group C (P<0.05). Conclusion: CMV could up-regulate the expression levels of ICAM-1 and MHC antigens, which was closely related to allograft rejection.

  6. TRPV-1-mediated elimination of residual iPS cells in bioengineered cardiac cell sheet tissues.

    Science.gov (United States)

    Matsuura, Katsuhisa; Seta, Hiroyoshi; Haraguchi, Yuji; Alsayegh, Khaled; Sekine, Hidekazu; Shimizu, Tatsuya; Hagiwara, Nobuhisa; Yamazaki, Kenji; Okano, Teruo

    2016-02-18

    The development of a suitable strategy for eliminating remaining undifferentiated cells is indispensable for the use of human-induced pluripotent stem (iPS) cell-derived cells in regenerative medicine. Here, we show for the first time that TRPV-1 activation through transient culture at 42 °C in combination with agonists is a simple and useful strategy to eliminate iPS cells from bioengineered cardiac cell sheet tissues. When human iPS cells were cultured at 42 °C, almost all cells disappeared by 48 hours through apoptosis. However, iPS cell-derived cardiomyocytes and fibroblasts maintained transcriptional and protein expression levels, and cardiac cell sheets were fabricated after reducing the temperature. TRPV-1 expression in iPS cells was upregulated at 42 °C, and iPS cell death at 42 °C was TRPV-1-dependent. Furthermore, TRPV-1 activation through thermal or agonist treatment eliminated iPS cells in cardiac tissues for a final concentration of 0.4% iPS cell contamination. These findings suggest that the difference in tolerance to TRPV-1 activation between iPS cells and iPS cell-derived cardiac cells could be exploited to eliminate remaining iPS cells in bioengineered cell sheet tissues, which will further reduce the risk of tumour formation.

  7. Expression of GSK-3β in renal allograft tissue and its significance in pathogenesis of chronic allograft dysfunction

    Directory of Open Access Journals (Sweden)

    Yan Qiang

    2012-01-01

    Full Text Available Abstract Objective To explore the expression of Glycogen synthase kinase 3 beta (GSK-3β in renal allograft tissue and its significance in the pathogenesis of chronic allograft dysfunction. Methods Renal allograft biopsy was performed in all of the renal allograft recipients with proteinuria or increased serum creatinine level who came into our hospital from January 2007 to December 2009. Among them 28 cases was diagnosed as chronic allograft dysfunction based on pahtological observation, including 21 males with a mean age of 45 ± 10 years old and 7 females with a mean age of 42 ± 9 years old. The time from kidney transplantation to biopsy were 1-9 (3.5 years. Their serum creatinine level were 206 ± 122 umol/L. Immunohistochemical assay and computer-assisted genuine color image analysis system (imagepro-plus 6.0 were used to detect the expression of GSK-3β in the renal allografts of 28 cases of recipients with chronic allograft dysfunction. Mean area and mean integrated optical density of GSK-3β expression were calculated. The relationship between expression level of GSK-3β and either the grade of inflammatory cell infiltration or interstitial fibrosis/tubular atrophy in renal allograft was analyzed. Five specimens of healthy renal tissue were used as controls. Results The expression level of the GSK-3β was significantly increased in the renal allograft tissue of recipients with chronic allograft dysfunction, compared to normal renal tissues, and GSK-3β expression became stronger along with the increasing of the grade of either inflammatory cell infiltration or interstitial fibrosis/tubular atrophy in renal allograft tissue. Conclusion There might be a positive correlation between either inflammatory cell infiltration or interstitial fibrosis/tubular atrophy and high GSK-3β expression in renal allograft tissue. Virtual slides The virtual slide(s for this article can be found here: http

  8. Comparative study of the role of professional versus semiprofessional or nonprofessional antigen presenting cells in the rejection of vascularized organ allografts.

    Science.gov (United States)

    Sundstrom, J B; Ansari, A A

    1995-12-01

    The immune systems of transplant recipients are progressively challenged with exposure to the multiple lineages of donor cells that comprise the vascularized organ allograft. Each lineage of such donor tissue constitutively expresses or can be induced to express varying densities of MHC antigens ranging from no expression of MHC to MHC class I only to both MHC class I and class II. In addition, the cell surface expression of a diverse assortment of costimulatory and cell adhesion molecules also varies in density in a tissue specific fashion within the allograft. The MHC class I/II molecules displayed on the donor cells contain within their clefts a constellation of processed protein antigens in the form of peptides derived from intracellular and to some extent extracellular sources. Therefore, the potential for each cell lineage to induce alloactivation and serve as a target for allospecific immune responses is dependent on the diversity and density of peptide-bearing MHC molecules, costimulatory molecules, and cell adhesion molecules. In addition, the T cell receptor repertoire of the recipient also contributes to the magnitude of the allogeneic response. Consequently, the variety of clinical outcomes following organ transplantation even with the institution of potent immunosuppressive (drug) therapies is not surprising, as it appears reasonable for such therapies to influence the allogeneic response against distinct lineages differentially. Our failure to prevent chronic human allograft rejection may therefore be due to our limited appreciation of the full spectrum of alloactivating experiences encountered by host T cells as they interact with donor cells of diverse tissue lineages. Investigations by our laboratory of the immunopathogenesis of chronic cardiac allograft rejection have revealed an intrinsic inability of human cardiac myocytes to process and present antigens, not only for primary but also for secondary alloimmune responses. One obvious explanation

  9. Regulatory T cell expressed MyD88 is critical for prolongation of allograft survival.

    Science.gov (United States)

    Borges, Christopher M; Reichenbach, Dawn K; Kim, Beom Seok; Misra, Aditya; Blazar, Bruce R; Turka, Laurence A

    2016-08-01

    MyD88 signaling directly promotes T-cell survival and is required for optimal T-cell responses to pathogens. To examine the role of T-cell-intrinsic MyD88 signals in transplantation, we studied mice with targeted T-cell-specific MyD88 deletion. Contrary to expectations, we found that these mice were relatively resistant to prolongation of graft survival with anti-CD154 plus rapamycin in a class II-mismatched system. To specifically examine the role of MyD88 in Tregs, we created a Treg-specific MyD88-deficient mouse. Transplant studies in these animals replicated the findings observed with a global T-cell MyD88 knockout. Surprisingly, given the role of MyD88 in conventional T-cell survival, we found no defect in the survival of MyD88-deficient Tregs in vitro or in the transplant recipients and also observed intact cell homing and expression of Treg effector molecules. MyD88-deficient Tregs also fail to protect allogeneic bone marrow transplant recipients from chronic graft-versus-host disease, confirming the observations of defective regulation seen in a solid organ transplant system. Together, our data define MyD88 as having a divergent requirement for cell survival in non-Tregs and Tregs, and a yet-to-be defined survival-independent requirement for Treg function during the response to alloantigen.

  10. Lymphoid-Like Structures with Distinct B Cell Areas in Kidney Allografts are not Predictive for Graft Rejection. A Non-human Primate Study.

    Science.gov (United States)

    Jonker, Margreet; Wubben, Jacqueline A M; 't Hart, Bert A; Haanstra, Krista G

    2015-12-01

    Kidney allograft biopsies were analyzed for the presence of B cell clusters/aggregates using CD20 staining. Few B cells were found in the diffuse interstitial infiltrates, but clusters of B cells were found in nodular infiltrates. These nodular infiltrates were smaller shortly after transplantation, and their size increased over time. At the time of clinical rejection, the nodules often presented as tertiary lymphoid structures (TLS) with lymphoid-like follicles. The presence of small B cell clusters during the first 2 months after transplantation was not associated with early rejection. Even in animals that did not reject their allograft, TLS-like structures were present and could disappear over time. Although TLS were more often found in samples with interstitial fibrosis and tubular atrophy (IFTA), TLS were also present in samples without IFTA. The presence and density of clusters resembling tertiary lymphoid structures most likely reflect an ongoing immune response inside the graft and do not necessarily signify a poor graft outcome or IFTA.

  11. Endothelial cell chimerism by fluorescence in situ hybridization in gender mismatched renal allograft biopsies

    Institute of Scientific and Technical Information of China (English)

    BAI Hong-wei; SHI Bing-yi; QIAN Ye-yong; NA Yan-qun; ZENG Xuan; ZHONG Ding-rong; LU Min; ZOU Wan-zhong; WU Shi-fei

    2007-01-01

    Background The blood vessels of a transplanted organ are the interface between donor and recipient. The endothelium in the blood vessels is thought to be the major target for graft rejection. Endothelial cells of a transplanted organ can be of recipient origin after transplantation. In this study, we tested whether endothelial chimerism correlated with the graft rejection and cold ischemia.Methods We studied the biopsy samples from 34 renal transplants of female recipients who received the kidney from a male donor for the presence of endothelial cells of recipient origin. We examined the tissue sections of renal biopsy samples by fluorescence in situ hybridization (FISH) for the presence of endothelial cells containing two X chromosomes using a biotinylated Y chromosome probe and digoxigenin labelled X chromosome probe, and then analyzed the relationship between the endothelial cell chimerism and the rejection and cold ischemia.Results Endothelial chimerism was common and irrespective of rejections (P>0.05). The cold ischemic time of chimerism group was longer than no chimerism group ((14.83±4.03) hours vs (11.27±3.87) hours, P<0.05).Conclusions There is no correlation between the percentage of recipient endothelial cells in vascular endothelial cells and the type of graft rejection. The endothelium damaged by ischemic injury might be repaired by the endothelial cells from the recipient.

  12. MHC mismatch inhibits neurogenesis and neuron maturation in stem cell allografts.

    Directory of Open Access Journals (Sweden)

    Zhiguo Chen

    Full Text Available BACKGROUND: The role of histocompatibility and immune recognition in stem cell transplant therapy has been controversial, with many reports arguing that undifferentiated stem cells are protected from immune recognition due to the absence of major histocompatibility complex (MHC markers. This argument is even more persuasive in transplantation into the central nervous system (CNS where the graft rejection response is minimal. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we evaluate graft survival and neuron production in perfectly matched vs. strongly mismatched neural stem cells transplanted into the hippocampus in mice. Although allogeneic cells survive, we observe that MHC-mismatch decreases surviving cell numbers and strongly inhibits the differentiation and retention of graft-derived as well as endogenously produced new neurons. Immune suppression with cyclosporine-A did not improve outcome but non-steroidal anti-inflammatory drugs, indomethacin or rosiglitazone, were able to restore allogeneic neuron production, integration and retention to the level of syngeneic grafts. CONCLUSIONS/SIGNIFICANCE: These results suggest an important but unsuspected role for innate, rather than adaptive, immunity in the survival and function of MHC-mismatched cellular grafts in the CNS.

  13. Treatment of refractory cutaneous ulcers with mixed sheets consisting of peripheral blood mononuclear cells and fibroblasts

    Science.gov (United States)

    Ueno, Koji; Takeuchi, Yuriko; Samura, Makoto; Tanaka, Yuya; Nakamura, Tamami; Nishimoto, Arata; Murata, Tomoaki; Hosoyama, Tohru; Hamano, Kimikazu

    2016-01-01

    The purpose of this study was to confirm the therapeutic effects of mixed sheets consisting of peripheral blood mononuclear cells (PBMNCs) and fibroblasts on cutaneous skin ulcers. Vascular endothelial growth factor (VEGF) secretion in mixed cell sheets was much higher than in PBMNCs and fibroblasts. Concerning the mechanism, transforming growth factor beta 1 and platelet-derived growth factor BB secreted from PBMNCs enhanced VEGF production in fibroblasts. In wounds created on the backs of diabetic mice, the therapeutic effect of mixed cell sheets was similar to that of daily treatment with trafermin, a recombinant human basic fibroblast growth factor. Although abnormal granulation tissue and inflammatory cell infiltration were observed in trafermin-treated wounds, the transplantation of mixed cell sheets resulted in the natural anatomy of subcutaneous tissues. The expression patterns of identical wound-healing factors in wounds were different between mixed sheet-transfected and trafermin-treated animals. Because mixed cell sheets transplanted into full-thickness skin defects were eliminated in hosts by day 21 in syngeneic transplantation models, allogeneic transplantation was performed using mice with different genetic backgrounds. The wound-healing rates were similar between the mixed cell sheet and trafermin groups. Our data indicated that mixed cell sheets represent a promising therapeutic material for cutaneous ulcers. PMID:27329845

  14. Three-dimensional cardiac tissue fabrication based on cell sheet technology.

    Science.gov (United States)

    Masuda, Shinako; Shimizu, Tatsuya

    2016-01-15

    Cardiac tissue engineering is a promising therapeutic strategy for severe heart failure. However, conventional tissue engineering methods by seeding cells into biodegradable scaffolds have intrinsic limitations such as inflammatory responses and fibrosis arising from the degradation of scaffolds. On the other hand, we have developed cell sheet engineering as a scaffold-free approach for cardiac tissue engineering. Confluent cultured cells are harvested as an intact cell sheet using a temperature-responsive culture surface. By layering cardiac cell sheets, it is possible to form electrically communicative three-dimensional cardiac constructs. Cell sheet transplantation onto damaged hearts in several animal models has revealed improvements in heart functions. Because of the lack of vasculature, the thickness of viable cardiac cell sheet-layered tissues is limited to three layers. Pre-vascularized structure formation within cardiac tissue and multi-step transplantation methods has enabled the formation of thick vascularized tissues in vivo. Furthermore, development of original bioreactor systems with vascular beds has allowed reconstruction of three-dimensional cardiac tissues with a functional vascular structure in vitro. Large-scale culture systems to generate pluripotent stem cell-derived cardiac cells can create large numbers of cardiac cell sheets. Three-dimensional cardiac tissues fabricated by cell sheet engineering may be applied to treat heart disease and tissue model construction.

  15. REPLACEMENT OF DENDRITIC CELLS IN THE AIRWAYS OF RAT LUNG ALLOGRAFTS

    NARCIS (Netherlands)

    UYAMA, T; Winter, Jobst; SAKIYAMA, S; MONDEN, Y; GROEN, Greetje; PROP, J

    1993-01-01

    It is unknown whether dendritic cells are able to migrate normally from the recipient into the allogeneic lung graft. Using monoclonal antibodies to major histocompatibility complex class II antigens (OX6 for both donor and recipient types; HIS19 for recipient type), we studied the replacement of do

  16. Characteristics of Tfh cells in the peripheral blood in recipients of liver allograft: A pilot study

    Directory of Open Access Journals (Sweden)

    Yan-chao SHI

    2015-01-01

    Full Text Available Objective To determine the expression characteristics of peripheral blood follicular helper T cells (Tfh and their molecules during pre- and post-transplantation period in liver transplant patients to explore the role of Tfh in alloreactive response after liver transplantation. Methods Twenty liver transplant (LT patients and 20 healthy individuals as control were enrolled in this study. Thirteen LT patients with stable liver function were included for cross-sectional study. Another seven LT patients with complete clinical data were included for follow-up study. The frequencies of Tfh cells were examined by flow cytometry. For the seven patients, Tfh cells and level of alanine aminotransferase (ALT were monitored dynamically for one month after LT. Results The frequencies of CD4+CXCR5+Tfh and CD4+CXCR5+PD-1+ cells in peripheral blood increased significantly after liver transplantation as compared with those before liver transplantation (P<0.05. In addition, the frequencies of CD4+CXCR5+ICOS+ cells showed a rising trend, but no statistical difference. In early follow-up period it was found that the frequencies of CD4+CXCR5+Tfh obviously increased after liver transplantation in patients with stable liver function, and reached the peak value after one week and then decreased. The ALT level also decreased when reaching peak 10 days after surgery. Interestingly, the frequencies of CD4+CXCR5+ Tfh in one patient with acute rejection after liver transplantation showed the same trend with ALT levels changes. Furthermore, the frequencies of CD4+CXCR5+Tfh, CD4+CXCR5+PD-1+ and CD4+CXCR5+ICOS+ cells in stable liver function group were higher than those in the healthy control group (P<0.05. Conclusion The CD4+CXCR5+Tfh cells in peripheral blood will be upregulated in liver transplant patients, which indicates that the Tfh may be involved in liver alloreactive response. DOI: 10.11855/j.issn.0577-7402.2014.12.08

  17. Organic fuel cells and fuel cell conducting sheets

    Science.gov (United States)

    Masel, Richard I.; Ha, Su; Adams, Brian

    2007-10-16

    A passive direct organic fuel cell includes an organic fuel solution and is operative to produce at least 15 mW/cm.sup.2 when operating at room temperature. In additional aspects of the invention, fuel cells can include a gas remover configured to promote circulation of an organic fuel solution when gas passes through the solution, a modified carbon cloth, one or more sealants, and a replaceable fuel cartridge.

  18. Stromal Cell-Derived Factor 1 Gene Polymorphism Is Associated with Susceptibility to Adverse Long-Term Allograft Outcomes in Non-Diabetic Kidney Transplant Recipients

    Directory of Open Access Journals (Sweden)

    Chung-Jieh Wang

    2014-07-01

    Full Text Available Although the genetic polymorphism of Stromal Cell-Derived Factor 1 (SDF-1 is associated with higher mortality of liver allograft recipients, the role of SDF-1 in the modulation of renal allograft outcomes is unclear. Between March 2000 and January 2008, we recruited 252 non-diabetic renal transplant recipients (RTRs. Baseline characteristics and blood chemistry were recorded. Genomic DNA extraction with polymerase chain reaction-restriction fragment length polymorphism was utilized to analyze the genetic polymorphisms of SDF-1 (rs1801157. The influence of SDF-1 on an adverse renal allograft outcome, defined as either a doubling of serum creatinine, graft failure, or patient death was evaluated. Sixteen patients with the SDF-1 AA/AG genotype and nine with the SDF-1 GG genotype reached an adverse outcome. According to Kaplan-Meier analysis, patients carrying the SDF-1 AA/AG genotype or A allele showed a significantly higher risk of reaching an adverse outcome than those carrying the SDF-1 GG genotype or G allele (p = 0.041; p = 0.0051, respectively; log rank test. Stepwise multivariate Cox proportional regression analysis revealed that patients carrying the SDF-1 AA/AG genotype and A allele had a 2.742-fold (95% CI. 1.106–6.799, p = 0.03 and 2.306-fold (95% CI. 1.254–4.24, p = 0.008 risk of experiencing an adverse outcome. The SDF-1 AA/AG genotype and A allele have a detrimental impact on the long-term outcome of RTRs.

  19. Hypoxia Created Human Mesenchymal Stem Cell Sheet for Prevascularized 3D Tissue Construction.

    Science.gov (United States)

    Zhang, Lijun; Xing, Qi; Qian, Zichen; Tahtinen, Mitchell; Zhang, Zhaoqiang; Shearier, Emily; Qi, Shaohai; Zhao, Feng

    2016-02-01

    3D tissue based on human mesenchymal stem cell (hMSC) sheets offers many interesting opportunities for regenerating multiple types of connective tissues. Prevascularizing hMSC sheets with endothelial cells (ECs) will improve 3D tissue performance by supporting cell survival and accelerating integration with host tissue. It is hypothesized that hypoxia cultured hMSC sheets can promote microvessel network formation and preserve stemness of hMSCs. This study investigates the vascularization of hMSC sheets under different oxygen tensions. It is found that the HN condition, in which hMSC sheets formed under physiological hypoxia (2% O2 ) and then cocultured with ECs under normoxia (20% O2 ), enables longer and more branched microvessel network formation. The observation is corroborated by higher levels of angiogenic factors in coculture medium. Additionally, the hypoxic hMSC sheet is more uniform and less defective, which facilitates fabrication of 3D prevascularized tissue construct by layering the prevascularized hMSC sheets and maturing in rotating wall vessel bioreactor. The hMSCs in the 3D construct still maintain multilineage differentiation ability, which indicates the possible application of the 3D construct for various connective tissues regeneration. These results demonstrate that hypoxia created hMSC sheets benefit the microvessel growth and it is feasible to construct 3D prevascularized tissue construct using the prevascularized hMSC sheets.

  20. Real-time, noninvasive optical coherence tomography of cross-sectional living cell-sheets in vitro and in vivo.

    Science.gov (United States)

    Kobayashi, Mari; Haraguchi, Yuji; Shimizu, Tatsuya; Mizuuchi, Kiminori; Iseki, Hiroshi

    2015-08-01

    Cell sheet technology has a history of application in regenerating various tissues, having successfully completed several clinical trials using autologous cell sheets. Tomographic analysis of living cell sheets is an important tool in the field of cell sheet-based regenerative medicine and tissue engineering to analyze the inner structure of layered living cells. Optical coherence tomography (OCT) is commonly used in ophthalmology to noninvasively analyze cross-sections of target tissues at high resolution. This study used OCT to conduct real-time, noninvasive analysis of living cell sheet cross sections. OCT showed the internal structure of cell sheets in tomographic images synthesized with backscatter signals from inside the living cell sheet without invasion or damage. OCT observations were used to analyze the static and dynamic behaviors of living cell sheets in vitro and in vivo including (1) the harvesting process of a C2C12 mouse skeletal myoblast sheet from a temperature-responsive culture surface; (2) cell-sheet adhesion onto various surfaces including a culture surface, a synthetic rubber glove, and the dorsal subcutaneous tissue of rats; and (3) the real-time propagation of beating rat cardiac cells within cardiac cell sheets. This study showed that OCT technology is a powerful tool in the field of cell sheet-based regenerative medicine and tissue engineering.

  1. An invention of thermo-responsive polymer surface, yielding cell sheet based regenerative therapies in cardiology and ophthalmology

    Directory of Open Access Journals (Sweden)

    Sawa Y

    2015-12-01

    limbal stem cell transplantation has been demonstrated successfully in animal model of limbal stem cell deficiency [10]. While the above is suitable for unilateral LSCD, in the case of bilateral total LSCD, corneal stem cell allograft transplantation [9] or cultivated oral mucosal epithelial transplantation (COMET are the treatments of choice available at the moment. In the COMET procedure, autologous oral mucosa is cultured and transplanted to the affected corneas. There are no risks of immune-mediated rejection and in the absence of autoimmune disease, immunosuppression is not required. While the epithelial sheets from the autologous mucosa are cultured, use of thermo-responsive culture dishes have enabled a carrier-free epithelial cell sheet transplantation as the cell sheets after in vitro culture can be detached by merely lowering the temperature of the thermo-responsive culture dishes [11]. These oral mucosal epithelial sheets have been transplanted in patients with corneal epithelial diseases with positive outcome [11]. Perspectives: The thermo-responsive polymer dish based technological capability of being able to grow cells as a sheet which can be transplanted without any carrier onto the surface of an organ or a tissue that requires a support for regeneration has enabled two novel clinical applications: Myocardial regeneration using skeletal myoblast patches which has become an approved cellular therapy [6]. A solution to bilateral corneal limbal stem cell deficiency by transplantation of autologous oral mucosal epithelial sheet [11]. In both the applications, transplantation of cells as a monolayer-sheet instead of dispersed cells has been proven to be advantageous. In cornea the entire surface can be uniformly covered if a cell sheet is used rather than transplantation of clumps of cells logically and the mechanism of the regeneration has been shown to be the replacement of the damaged corneal epithelial cells with the transplanted cells [12]. In case of

  2. Risk factors of cardiac allograft vasculopathy.

    Science.gov (United States)

    Szyguła-Jurkiewicz, Bożena; Szczurek, Wioletta; Gąsior, Mariusz; Zembala, Marian

    2015-12-01

    Despite advances in prevention and treatment of heart transplant rejection, development of cardiac allograft vasculopathy (CAV) remains the leading factor limiting long-term survival of the graft. Cardiac allograft vasculopathy etiopathogenesis is not fully understood, but a significant role is attributed to endothelial cell damage, caused by immunological and non-immunological mechanisms. Immunological factors include the differences between the recipient's and the donor's HLA systems, the presence of alloreactive antibodies and episodes of acute rejection. Among the non-immunological factors the most important are the age of the donor, ischemia-reperfusion injury and cytomegalovirus infection. The classical cardiovascular risk factors (diabetes, hypertension, obesity and hyperlipidemia) are also important. This study presents an up-to-date overview of current knowledge on the vasculopathy etiopathogenesis and the role played by endothelium and inflammatory processes in CAV, and it also investigates the factors which may serve as risk markers of cardiac allograft vasculopathy.

  3. Influence of mycophenolate mofetil (MMF) upon the maturation and allo-stimulatory activity of cultured progenitors of dendritic cells and the effects on the tolerance induction in allograft recipients

    Institute of Scientific and Technical Information of China (English)

    CONGHUIHAN; YUXINWANG; QINGLIANG; MINGZHANG; YINGWANG; MINGYIN; ZHILIANMING; KELIZHENG

    2005-01-01

    To investigate the influence of mycophenolate mofetil (MMF) upon the maturation and the allo-stimulatory activity of cultured progenitors of dendritic cells (DCp), and to evaluate the effects of the pre-treated dentritic cells of recipients with MMF on the tolerance induction as well as its possible mechanism, GM-CSF and MMF were added to the in vitro cultured progenitor cells, and the immuno-phenotypical analysis was performed by means of flow cytometry. The secretion of IL-12 was detected by ELISA and the stimulatory activities of DCp on allogeneic T cells were observed by mixed lymphocyte reaction.Twenty-four C57BL/6 mice were divided into 3 groups (each with 8 mice), in which group A of mice accepted allografts of heart from BALB/c mice, group B of mice had received untreated DCp from donors of BALB/c mice 7 days before transplantation, and C57BL/6 mice in group C were treated by injection with MMF-treated allografts of heart from BALB/c mice 7 days before transplantation. The survival times of allografts and the changes of the cytokine levels in sere of the recipient mice were observed after transplantation. The experimental results showed that MMF could significantly inhibit the expressions of the costimulatory molecules CD80 and CD86 on DCs and the secretion of IL-12 and the allo-stimulatory activities of DCs were also markedly inhibited. The survival times of allografts in group B of mice were longer than those in group A, while the group C showed the longest survival times of allografts, with a marked reduction in the production of the Thl type cytokines. It is evident that MMF has a suppressive effect on the maturation and allo-stimulatory activities of the cultured dendritic cell progenitors, thus leading to a donor specific tolerance in heart-transplanted recipients.

  4. Periodontal Ligament Cell Sheet Engineering: A new Possible Strategy to Promote Periodontal Regeneration

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    Dong-sheng Zhang

    2010-06-01

    Full Text Available Introduction: Osseointegration represents a direct structural and functional connection between ordered, living bone and the surface of a load-carrying implant without the periodontium. As a result, im-plant fracture or aggressive bone loss sometime occurs because the patient cannot feel the mechanical overloads exerted on the implant. Until now, no available method has been used to solve this problem.The hypothesis: Periodontal ligament (PDL cells are a desirable cell population capable of regenerating a functional periodontal at-tachment apparatus. Cell sheet engineering has emerged as a novel alternative approach for periodontal tissue engineering without the disruption of both critical cell surface proteins such as ion channels, growth factor receptors and cell-to-cell junction proteins. PDL cells can be isolated from an extracted tooth and can be cultured on temperature-responsive culture dishes at 37°C. Transplantable cell sheets can be harvested by reducing the temperature to 20°C, and would be transplanted into the implant beds before insertion of the implant.Evaluation of the hypothesis: Controlling the differentiation of PDL cell sheets to different functional peri-implant periodontal tissues is very difficult. Further studies are required to determine the fate of implanted cells. Fluorescence protein-labeled cell sheets would be a good approach to investigate the fate of the grafted cell sheet.

  5. Renal Structural Changes after Kidney Allograft Transplantation

    NARCIS (Netherlands)

    Bakker, R.C.

    2005-01-01

    In vitro studies done on human proximal tubular epithelial cells showed no direct cytotoxicity of cyclosporine A. The 15-year results of an open randomized trial comparing cyclosporine withdrawal and conversion to azathioprine with continued cyclosporine treatment after kidney allograft transplantat

  6. SDF-1/CXCR4/CXCR7 is pivotal for vascular smooth muscle cell proliferation and chronic allograft vasculopathy.

    Science.gov (United States)

    Thomas, Michael N; Kalnins, Aivars; Andrassy, Martin; Wagner, Anne; Klussmann, Sven; Rentsch, Markus; Habicht, Antje; Pratschke, Sebastian; Stangl, Manfred; Bazhin, Alexandr V; Meiser, Bruno; Fischereder, Michael; Werner, Jens; Guba, Markus; Andrassy, Joachim

    2015-12-01

    Chronic rejection remains a major obstacle in transplant medicine. Recent studies suggest a crucial role of the chemokine SDF-1 on neointima formation after injury. Here, we investigate the potential therapeutic effect of inhibiting the SDF-1/CXCR4/CXCR7 axis with an anti-SDF-1 Spiegelmer (NOX-A12) on the development of chronic allograft vasculopathy. Heterotopic heart transplants from H-2bm12 to B6 mice and aortic transplants from Balb/c to B6 were performed. Mice were treated with NOX-A12. Control animals received a nonfunctional Spiegelmer (revNOX-A12). Samples were retrieved at different time points and analysed by histology, RT-PCR and proliferation assay. Blockade of SDF-1 caused a significant decrease in neointima formation as measured by intima/media ratio (1.0 ± 0.1 vs. 1.8 ± 0.1, P SDF-1 inhibition (3.42 ± 0.37 vs. 1.67 ± 0.33, P SDF-1/CXCR4/CXCR7 plays a critical role in the development of chronic allograft vasculopathy (CAV). Therefore, pharmacological inhibition of SDF-1 with NOX-A12 may represent a therapeutic option to ameliorate chronic rejection changes.

  7. Engineering tubular bone using mesenchymal stem cell sheets and coral particles

    Energy Technology Data Exchange (ETDEWEB)

    Geng, Wenxin [Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, No.229 North Taibai Road, Xi’an 710069 (China); Ma, Dongyang [Department of Oral and Maxillofacial Surgery, Lanzhou General Hospital, Lanzhou Command of PLA, BinHe 333 South Road, Lanzhou 730052 (China); Yan, Xingrong; Liu, Liangqi; Cui, Jihong; Xie, Xin; Li, Hongmin [Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, No.229 North Taibai Road, Xi’an 710069 (China); Chen, Fulin, E-mail: chenfl@nwu.edu.cn [Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, No.229 North Taibai Road, Xi’an 710069 (China)

    2013-04-19

    Highlights: • We developed a novel engineering strategy to solve the limitations of bone grafts. • We fabricated tubular constructs using cell sheets and coral particles. • The composite constructs showed high radiological density and compressive strength. • These characteristics were similar to those of native bone. -- Abstract: The development of bone tissue engineering has provided new solutions for bone defects. However, the cell-scaffold-based approaches currently in use have several limitations, including low cell seeding rates and poor bone formation capacity. In the present study, we developed a novel strategy to engineer bone grafts using mesenchymal stem cell sheets and coral particles. Rabbit bone marrow mesenchymal stem cells were continuously cultured to form a cell sheet with osteogenic potential and coral particles were integrated into the sheet. The composite sheet was then wrapped around a cylindrical mandrel to fabricate a tubular construct. The resultant tubular construct was cultured in a spinner-flask bioreactor and subsequently implanted into a subcutaneous pocket in a nude mouse for assessment of its histological characteristics, radiological density and mechanical property. A similar construct assembled from a cell sheet alone acted as a control. In vitro observations demonstrated that the composite construct maintained its tubular shape, and exhibited higher radiological density, compressive strength and greater extracellular matrix deposition than did the control construct. In vivo experiments further revealed that new bone formed ectopically on the composite constructs, so that the 8-week explants of the composite sheets displayed radiological density similar to that of native bone. These results indicate that the strategy of using a combination of a cell sheet and coral particles has great potential for bone tissue engineering and repairing bone defects.

  8. Antibody-dependent NK cell activation is associated with late kidney allograft dysfunction and the complement-independent alloreactive potential of donor-specific antibodies

    Directory of Open Access Journals (Sweden)

    Tristan Legris

    2016-08-01

    Full Text Available Although kidney transplantation remains the best treatment for end-stage renal failure, it is limited by chronic humoral aggression of the graft vasculature by donor-specific antibodies (DSAs. The complement-independent mechanisms that lead to the antibody-mediated rejection (ABMR of kidney allografts remain poorly understood. Increasing lines of evidence have revealed the relevance of natural killer (NK cells as innate immune effectors of antibody-dependent cellular cytotoxicity, but few studies have investigated their alloreactive potential in the context of solid organ transplantation. Our study aimed to investigate the potential contribution of the antibody-dependent alloreactive function of NK cells to kidney graft dysfunction. We first conducted an observational study to investigate whether the cytotoxic function of NK cells is associated with chronic allograft dysfunction. The NK-Cellular Humoral Activation Test (NK-CHAT was designed to evaluate the recipient and antibody-dependent reactivity of NK cells against allogeneic target cells. The release of CD107a/Lamp1+ cytotoxic granules, resulting from the recognition of rituximab-coated B cells by NK cells, was analyzed in 148 kidney transplant recipients (KTRs, mean graft duration: 6.2 years. Enhanced ADCC responsiveness was associated with reduced graft function and identified as an independent risk factor predicting a decline in the estimated glomerular filtration rate (eGFR over a 1-year period (hazard ratio: 2.83. In a second approach, we used the NK-CHAT to reveal the cytotoxic potential of circulating alloantibodies in vitro. The level of CD16 engagement resulting from the in vitro recognition of serum-coated allogeneic B cells or splenic cells was further identified as a specific marker of DSA-induced ADCC. The NK-CHAT scoring of sera obtained from 40 patients at the time of transplant biopsy was associated with ABMR diagnosis. Our findings indicate that despite the administration

  9. Latest status of the clinical and industrial applications of cell sheet engineering and regenerative medicine.

    Science.gov (United States)

    Egami, Mime; Haraguchi, Yuji; Shimizu, Tatsuya; Yamato, Masayuki; Okano, Teruo

    2014-01-01

    Cell sheet engineering, which allows tissue engineering to be realized without the use of biodegradable scaffolds as an original approach, using a temperature-responsive intelligent surface, has been applied in regenerative medicine for various tissues, and a number of clinical studies have been already performed for life-threatening diseases. By using the results and findings obtained from the initial clinical studies, additional investigative clinical studies in several tissues with cell sheet engineering are currently in preparation stage. For treating many patients effectively by cell sheet engineering, an automated system integrating cell culture, cell-sheet fabrication, and layering is essential, and the system should include an advanced three-dimensional suspension cell culture system and an in vitro bioreactor system to scale up the production of cultured cells and fabricate thicker vascularized tissues. In this paper, cell sheet engineering, its clinical application, and further the authors' challenge to develop innovative cell culture systems under newly legislated regulatory platform in Japan are summarized and discussed.

  10. N-Isopropylacrylamide-co-glycidylmethacrylate as a Thermoresponsive Substrate for Corneal Endothelial Cell Sheet Engineering

    Directory of Open Access Journals (Sweden)

    Bernadette K. Madathil

    2014-01-01

    Full Text Available Endothelial keratoplasty is a recent shift in the surgical treatment of corneal endothelial dystrophies, where the dysfunctional endothelium is replaced whilst retaining the unaffected corneal layers. To overcome the limitation of donor corneal shortage, alternative use of tissue engineered constructs is being researched. Tissue constructs with intact extracellular matrix are generated using stimuli responsive polymers. In this study we evaluated the feasibility of using the thermoresponsive poly(N-isopropylacrylamide-co-glycidylmethacrylate polymer as a culture surface to harvest viable corneal endothelial cell sheets. Incubation below the lower critical solution temperature of the polymer allowed the detachment of the intact endothelial cell sheet. Phase contrast and scanning electron microscopy revealed the intact architecture, cobble stone morphology, and cell-to-cell contact in the retrieved cell sheet. Strong extracellular matrix deposition was also observed. The RT-PCR analysis confirmed functionally active endothelial cells in the cell sheet as evidenced by the positive expression of aquaporin 1, collagen IV, Na+-K+ ATPase, and FLK-1. Na+-K+ ATPase protein expression was also visualized by immunofluorescence staining. These results suggest that the in-house developed thermoresponsive culture dish is a suitable substrate for the generation of intact corneal endothelial cell sheet towards transplantation for endothelial keratoplasty.

  11. Construction and characterization of osteogenic and vascular endothelial cell sheets from rat adipose-derived mesenchymal stem cells.

    Science.gov (United States)

    Zhang, Hualin; Yu, Na; Zhou, Yueli; Ma, Hairong; Wang, Juan; Ma, Xuerong; Liu, Jinsong; Huang, Jin; An, Yilin

    2016-10-01

    In this study, adipose-derived mesenchymal stem cells (ADSCs) were isolated from adipose tissues of rats. Flow cytometry identification showed that ADSCs of passage 3 highly expressed CD29 and CD44, but hardly expressed CD31 and CD45. Adipogenic, osteogenic, and chondrogenic differentiation were confirmed by the results of oil red O staining, alkaline phosphatase (ALP), and alcian blue staining, respectively. ADSCs at a density of 1×10(6)/cm(2) were cultured in the osteogenic medium and the osteogenic cell sheets could be obtained after 14 d. The cell sheets were positive with von kossa staining. The transmission electron microscopy (TEM) result showed that needle-like calcium salt crystals were deposited on the ECM. These results suggested that the osteogenic cell sheets may have potential osteogenesis ability. ADSCs at a density of 1×10(6)/cm(2) were cultured in the endothelial cell growth medium-2 and the endothelial cell sheets can be formed after 16 d of culture. The TEM image confirmed that the Weibel-Palade corpuscle was seen in the cells. The expression of CD31 was positive, suggesting that the endothelial cell sheets may have a strong ability to form blood vessels. In this study, two types of cell sheets with the potential abilities of osteogenesis and blood vessels formation were obtained by induced culture of ADSCs in vitro, which lays a foundation to build vascularized tissue engineered bone for the therapy of bone defects.

  12. Combination of monoclonal antibodies with DST inhibits accelerated rejection mediated by memory T cells to induce long-lived heart allograft acceptance in mice.

    Science.gov (United States)

    Shao, Wei; Chen, Jibing; Dai, Helong; Peng, Yuanzheng; Wang, Feng; Xia, Junjie; Thorlacius, Henrik; Zhu, Qi; Qi, Zhongquan

    2011-08-30

    Donor-reactive memory T cells mediated accelerated rejection is known as a barrier to the survival of transplanted organs. We investigated the combination of different monoclonal antibodies (mAbs) and donor-specific transfusion (DST) in memory T cells-based adoptive mice model. In the presence of donor-reactive memory T cells, the mean survival time (MST) of grafts in the anti-CD40L/LFA-1/DST group was 49.8d. Adding anti-CD44/CD70 mAbs to anti-CD40L/LFA-1/DST treatment. The MST was more than 100 d (MST>100 d). Compared with anti-CD40L/LFA-1/DST group, anti-CD40L/LFA-1/CD44/CD70/DST group notably reduced the expansion of memory T cells, enhanced the proportion of CD4+Foxp3+ regulatory T cells (Tregs) and suppressed donor-specific responses. Our data suggest that anti-CD40L/LFA-1/CD44/CD70mAbs and DST can synergistically inhibit accelerated rejection mediated by memory T cells to induce long-lived heart allograft acceptance in mice.

  13. Bioengineered periosteal progenitor cell sheets to enhance tendon-bone healing in a bone tunnel

    Directory of Open Access Journals (Sweden)

    Chih-Hsiang Chang

    2012-12-01

    Full Text Available Background: Tendon-bone tunnel healing is crucial for long term success in anterior cruciate liga­ment (ACL reconstruction. The periosteum contains osteochondral progenitor cells that can differenti­ate into osteoblasts and chondroblasts during tendon-bone healing. We developed a scaf­fold-free method using polymerized fibrin-coated dishes to make functional periosteal progenitor cell (PPC sheets. Bioengineered PPC sheets for enhancing tendon-bone healing were evaluated in an extra-articular bone tunnel model in rabbit. Methods: PPC derived from rabbit tibia periosteum, cultivated on polymerized fi­brin-coated dishes and harvested as PPC sheet. A confocal microscopy assay was used to evaluate the morphology of PPC sheets. PPC sheets as a periosteum to wrap around hamstring tendon grafts were pulled into a 3-mm diameter bone tunnel of tibia, and compared with a tendon graft without PPC sheets treatment. Rabbits were sacrificed at 4 and 8 weeks postoperatively for biochemical as­say and histological assay to demonstrate the enhancement of PPC sheets in tendon-bone healing. Results: PPC spread deposit on fibrin on the dish surface with continuous monolayer PPC was ob­served. Histological staining revealed that PPC sheets enhance collagen and glycosaminoglycans deposi­tion with fibrocartilage formation in the tendon-bone junction at 4 weeks. Collagen fiber with fibrocartilage formation at tendon-bone junction was also found at 8 weeks. Matured fibrocartilage and dense collagen fiber were formed at the tendon-bone interface at 8 weeks by Masson trichrome and Safranin-O staining Conclusions: Periosteal progenitor cell monolayer maintains the differentiated capacity and osteochon­dral potential in order to promote fibrocartilage formation in tendon-bone junction. Bioengi­neered PPC sheets can offer a new feasible therapeutic strategy of a novel approach to en­hance tendon-bone junction healing.

  14. Local Mechanical Stimulation of Mardin-Darby Canine Kidney Cell Sheets on Temperature-Responsive Hydrogel

    Directory of Open Access Journals (Sweden)

    Toshihiro Akaike

    2012-01-01

    Full Text Available Collective motion of cell sheets plays a role not only in development and repair, but also in devastating diseases such as cancer. However, unlike single-cell motility, collective motion of cell sheets involves complex cell-cell communication during migration; therefore, its mechanism is largely unknown. To elucidate propagation of signaling transduced by cell-cell interaction, we designed a hydrogel substrate that can cause local mechanical stretching of cell sheets. Poly (N-isopropyl acrylamide (PNIPAAm hydrogel is a temperature-responsive polymer gel whose volume changes isotropically in response to temperature changes below 37 °C. We designed a combined hydrogel substrate consisting of collagen-immobilized PNIPAAm as the local stimulation side and polyacrylamide (PAAm as the non-stimulation side to assess propagation of mechanical transduction. Mardin-Darby canine kidney (MDCK cells adhered to the collagen-immobilized PNIPAAm gel increased it area and were flattened as the gel swelled with temperature decrease. E-cadherin in these cells became undetectable in some domains, and actin stress fibers were more clearly observed at the cell base. In contrast, E-cadherin in cells adhered to the collagen-immobilized PAAm side was equally stained as that in cells adhered to the collagen-immobilized PAAm side even after temperature decrease. ERK1/2 MAPK activation of cells on the non-stimulated substrate occurred after partial stretching of the cell sheet suggesting the propagation of signaling. These results indicate that a change in the balance of mechanical tension induced by partial stretching of cell sheets leads to activation and propagation of the cell signaling.

  15. DENDRITIC CELLS WITH TGF-ß1 and IL-2 DIFFERENTIATE NAÏVE CD4+ T CELLS INTO ALLOANTIGEN SPECIFIC AND ALLOGRAFT PROTECTIVE FOXP3+ REGULATORY T CELLS

    Science.gov (United States)

    Yang, Hua; Cheng, Elaine Y; Sharma, Vijay K; Lagman, Mila; Chang, Christina; Song, Ping; Ding, Ruchuang; Muthukumar, Thangamani; Suthanthiran, Manikkam

    2013-01-01

    Background Naturally occurring, thymic-derived Foxp3+CD25+CD4+ regulatory T cells (natural Tregs) are pivotal for the maintenance of self-tolerance. Natural Tregs, however, are sparse and lack alloantigen specificity and these properties pose challenges for their use in clinical transplantation. Methods We established mixed leukocyte reaction (MLR) with dendritic cells (DCs) as stimulators and CD4+ T cells as responders and supplemented the MLR with IL-2 and TGF-β1, and investigated whether DCs+ IL-2 +TGF-β1 differentiate the polyclonal CD4+ cells into alloantigen specific and allograft protective Tregs. Results We found a greater than a ten-fold increase in Foxp3+ CD25+ subpopulation (P<0.01) following stimulation of BALB/c CD4+ cells with C57BL/6 (B6) CD11c+ DCs + IL-2 + TGF-β1 in the MLR. Levels of TGF-β1 mRNA (P=0.01) and the ratios of TGF-β1 mRNA to granzyme B mRNA (P=0.0003) and Foxp3 mRNA to granzyme B mRNA (P<0.01) were higher in alloantigen induced Tregs compared to natural Tregs. Alloantigen induced Tregs suppressed MLR at a 16:1 responder to suppressor ratio whereas natural Tregs suppressed at 4:1. Suppression by alloantigen induced Tregs was alloantigen specific and was observed at the level of responder cells and at the level of stimulator cells. In a fully H-2 mismatched, non-lymphopenic, immunocompetent mouse islet transplantation model, alloantigen induced Tregs but not natural Tregs prolonged survival of islet allografts without any other immunosuppressive therapy (P=0.0003), and the protection was alloantigen specific. Conclusions A combination of CD11c+ DCs, IL-2 and TGF-β1 may help differentiate naïve, high abundant CD4+ T in to alloantigen specific and allograft protective Foxp3 + Tregs. PMID:22270834

  16. Uptake of donor lymphocytes treated with 8-methoxypsoralen and ultraviolet A light by recipient dendritic cells induces CD4{sup +}CD25{sup +}Foxp3{sup +} regulatory T cells and down-regulates cardiac allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, De-Hua [Organ Transplant Center, Chinese PLA 309th Hospital, No. 17A Hei-Shan-Hu Road, Beijing 100091 (China); Dou, Li-Ping [Department of Hematology, Chinese PLA General Hospital, No. 28 Fu-Xing Road, Beijing 100853 (China); Wei, Yu-Xiang; Du, Guo-Sheng; Zou, Yi-Ping; Song, Ji-Yong; Zhu, Zhi-Dong; Cai, Ming; Qian, Ye-Yong [Organ Transplant Center, Chinese PLA 309th Hospital, No. 17A Hei-Shan-Hu Road, Beijing 100091 (China); Shi, Bing-Yi, E-mail: shibingyi@medmail.com.cn [Organ Transplant Center, Chinese PLA 309th Hospital, No. 17A Hei-Shan-Hu Road, Beijing 100091 (China)

    2010-05-14

    Extracorporeal photopheresis (ECP) is an effective immunomodulatory therapy and has been demonstrated to be beneficial for graft-vs-host disease and solid-organ allograft rejection. ECP involves reinfusion of a patient's autologous peripheral blood leukocytes treated ex vivo with 8-methoxypsoralen and UVA light radiation (PUVA). Previous studies focused only on ECP treatment of recipient immune cells. Our study is the first to extend the target of ECP treatment to donor immune cells. The results of in vitro co-culture experiments demonstrate uptake of donor PUVA-treated splenic lymphocytes (PUVA-SPs) by recipient immature dendritic cells (DCs). Phagocytosis of donor PUVA-SPs does not stimulate phenotype maturation of recipient DCs. In the same co-culture system, donor PUVA-SPs enhanced production of interleukin-10 and interferon-{gamma} by recipient DCs and impaired the subsequent capability of recipient DCs to stimulate recipient naive T cells. Phagocytosis of donor PUVA-SP (PUVA-SP DCs) by recipient DCs shifted T-cell responses in favor of T helper 2 cells. Infusion of PUVA-SP DCs inhibited cardiac allograft rejection in an antigen-specific manner and induced CD4{sup +}CD25{sup high}Foxp3{sup +} regulatory T cells. In conclusion, PUVA-SP DCs simultaneously deliver the donor antigen and the regulatory signal to the transplant recipient, and thus can be used to develop a novel DC vaccine for negative immune regulation and immune tolerance induction.

  17. Facile fabrication of tissue-engineered constructs using nanopatterned cell sheets and magnetic levitation

    Science.gov (United States)

    Penland, Nisa; Choi, Eunpyo; Perla, Mikael; Park, Jungyul; Kim, Deok-Ho

    2017-02-01

    We report a simple and versatile method for in vitro fabrication of scaffold-free tissue-engineered constructs with predetermined cellular alignment, by combining magnetic cell levitation with thermoresponsive nanofabricated substratum (TNFS) based cell sheet engineering technique. The TNFS based nanotopography provides contact guidance cues for regulation of cellular alignment and enables cell sheet transfer, while magnetic nanoparticles facilitate the magnetic levitation of the cell sheet. The temperature-mediated change in surface wettability of the thermoresponsive poly(N-isopropylacrylamide), substratum enables the spontaneous detachment of cell monolayers, which can then be easily manipulated through use of a ring or disk shaped magnet. Our developed platform could be readily applicable to production of tissue-engineered constructs containing complex physiological structures for the study of tissue structure-function relationships, drug screening, and regenerative medicine.

  18. Preferential accumulation of T helper cells but not cytotoxic T cells characterizes benign subclinical rejection of human liver allografts.

    Science.gov (United States)

    Baumann, Anna K; Schlue, Jerome; Noyan, Fatih; Hardtke-Wolenski, Matthias; Lehner, Frank; Barg-Hock, Hannelore; Klempnauer, Juergen; Manns, Michael P; Taubert, Richard; Jaeckel, Elmar

    2016-07-01

    Subclinical rejection (SCR) is a common event in protocol biopsies after liver transplantation (LT). So far the interpretation of the underlying histological changes and clinical significance is limited. Previous studies were restricted to SCR manifestations within the first weeks after transplantation with limited follow-up. We analyzed clinical data from our prospective protocol biopsy program and found late SCR (at least 3 months after transplantation) to be a common event (41/94 patients). SCR manifested much later than acute cellular rejection (ACR). In the second year after transplantation, the SCR incidence in protocol biopsies reached a plateau of approximately 25% and remained at this level until the latest observed manifestations more than 5 years after transplantation. During a median follow-up of 32 months after SCR, no acute or chronic rejection, relevant graft fibrosis, graft loss, or liver-related death occurred even without specific therapy for SCR. Immunophenotyping of liver biopsies during SCR showed that similar to ACR, the composition of intrahepatic T cells depended on the severity of histological rejection. However, SCR showed a different pattern of infiltrating T cells with a stronger accumulation of CD4(+) cells, an increasing CD4(+) /CD8(+) ratio, and an increasing CD4(+) forkhead box P3 (FOXP3)(+) regulatory T cell (Treg)/CD8(+) ratio, which was not seen in ACR. These intrahepatic T cell patterns were not reflected in the peripheral blood. In conclusion, late SCR after LT has a good clinical prognosis, and it seems safe to leave it untreated. This benign clinical course compared to ACR is associated with intrahepatic T cell infiltration patterns showing less cytotoxic T cells and more CD4(+) FOXP3(+) Tregs. Liver Transplantation 22 943-955 2016 AASLD.

  19. Addition of Adipose-Derived Stem Cells to Mesenchymal Stem Cell Sheets Improves Bone Formation at an Ectopic Site

    Directory of Open Access Journals (Sweden)

    Zhifa Wang

    2016-02-01

    Full Text Available To determine the effect of adipose-derived stem cells (ADSCs added to bone marrow-derived mesenchymal stem cell (MSC sheets on bone formation at an ectopic site. We isolated MSCs and ADSCs from the same rabbits. We then prepared MSC sheets for implantation with or without ADSCs subcutaneously in the backs of severe combined immunodeficiency (SCID mice. We assessed bone formation at eight weeks after implantation by micro-computed tomography and histological analysis. In osteogenic medium, MSCs grew to form multilayer sheets containing many calcium nodules. MSC sheets without ADSCs formed bone-like tissue; although neo-bone and cartilage-like tissues were sparse and unevenly distributed by eight weeks after implantation. In comparison, MSC sheets with ADSCs promoted better bone regeneration as evidenced by the greater density of bone, increased mineral deposition, obvious formation of blood vessels, large number of interconnected ossified trabeculae and woven bone structures, and greater bone volume/total volume within the composite constructs. Our results indicate that although sheets of only MSCs have the potential to form tissue engineered bone at an ectopic site, the addition of ADSCs can significantly increase the osteogenic potential of MSC sheets. Thus, the combination of MSC sheets with ADSCs may be regarded as a promising therapeutic strategy to stimulate bone regeneration.

  20. Macrophage-to-Myofibroblast Transition Contributes to Interstitial Fibrosis in Chronic Renal Allograft Injury.

    Science.gov (United States)

    Wang, Ying-Ying; Jiang, Hong; Pan, Jun; Huang, Xiao-Ru; Wang, Yu-Cheng; Huang, Hong-Feng; To, Ka-Fai; Nikolic-Paterson, David J; Lan, Hui-Yao; Chen, Jiang-Hua

    2017-02-16

    Interstitial fibrosis is an important contributor to graft loss in chronic renal allograft injury. Inflammatory macrophages are associated with fibrosis in renal allografts, but how these cells contribute to this damaging response is not clearly understood. Here, we investigated the role of macrophage-to-myofibroblast transition in interstitial fibrosis in human and experimental chronic renal allograft injury. In biopsy specimens from patients with active chronic allograft rejection, we identified cells undergoing macrophage-to-myofibroblast transition by the coexpression of macrophage (CD68) and myofibroblast (α-smooth muscle actin [α-SMA]) markers. CD68(+)/α-SMA(+) cells accounted for approximately 50% of the myofibroblast population, and the number of these cells correlated with allograft function and the severity of interstitial fibrosis. Similarly, in C57BL/6J mice with a BALB/c renal allograft, cells coexpressing macrophage markers (CD68 or F4/80) and α-SMA composed a significant population in the interstitium of allografts undergoing chronic rejection. Fate-mapping in Lyz2-Cre/Rosa26-Tomato mice showed that approximately half of α-SMA(+) myofibroblasts in renal allografts originated from recipient bone marrow-derived macrophages. Knockout of Smad3 protected against interstitial fibrosis in renal allografts and substantially reduced the number of macrophage-to-myofibroblast transition cells. Furthermore, the majority of macrophage-to-myofibroblast transition cells in human and experimental renal allograft rejection coexpressed the M2-type macrophage marker CD206, and this expression was considerably reduced in Smad3-knockout recipients. In conclusion, our studies indicate that macrophage-to-myofibroblast transition contributes to interstitial fibrosis in chronic renal allograft injury. Moreover, the transition of bone marrow-derived M2-type macrophages to myofibroblasts in the renal allograft is regulated via a Smad3-dependent mechanism.

  1. [Tubulointerstitial rejection of renal allografts].

    Science.gov (United States)

    Malušková, Jana; Honsová, Eva

    2015-01-01

    Tubulo-intersticial rejection represents T-cell mediated rejection of kidney allografts with the morphology of immune-mediated interstitial nephritis. Diagnosis is dependent on the histopathological evaluation of a graft biopsy sample. The key morphological features are interstitial inflammatory infiltrate and damage to tubular epithelial cell which in severe cases can result in the ruptures of the tubular basement membranes. The differential diagnosis of tubulo-interstitial rejection includes acute interstitial nephritis and viral inflammatory kidney diseases, mainly polyomavirus nephropathy.

  2. Low Sheet Resistance Counter Electrode in Dye-sensitized Solar Cell

    Institute of Scientific and Technical Information of China (English)

    Gui Qiang WANG; Rui Feng LIN; Miao WANG; Chang Neng ZHANG; Yuan LIN; Xu Rui XIAO; Xue Ping LI

    2004-01-01

    In order to search for the high efficiency and low sheet resistance counter electrode in dye-sensitized solar cell, we used Ti plate as the conducting substrate to prepare the counter electrode by thermal decomposition of H2PtCl6. Ti plate counter electrode shows low sheet resistance, good reflecting performance and matching kinetics. The dye-sensitized solar cell with the Ti plate counter electrode shows better photovoltaic performance than that of the cell with the fluorine-doped tin oxide-coated glass counter electrode.

  3. Calculated and Experimental Research of Sheet Resistances of Laser-Doped Silicon Solar Cells

    Science.gov (United States)

    Li, Tao; Wang, Wen-Jing

    2015-02-01

    The calculated and experimental research of sheet resistances of crystalline silicon solar cells by dry laser doping is investigated. The nonlinear numerical model on laser melting of crystalline silicon and liquid-phase diffusion of phosphorus atoms by dry laser doping is analyzed by the finite difference method implemented in MATLAB. The melting period and melting depth of crystalline silicon as a function of laser energy density is achieved. The effective liquid-phase diffusion of phosphorus atoms in melting silicon by dry laser doping is confirmed by the rapid decrease of sheet resistances in experimental measurement. The plateau of sheet resistances is reached at around 15Ω/□. The calculated sheet resistances as a function of laser energy density is obtained and the calculated results are in good agreement with the corresponding experimental measurement. Due to the successful verification by comparison between experimental measurement and calculated results, the simulation results could be used to optimize the virtual laser doping parameters.

  4. Bay Area Transit Agencies Propel Fuel Cell Buses Toward Commercialization (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2010-07-01

    This fact sheet describes the Zero Emission Bay Area (ZEBA) demonstration of the next generation of fuel cells buses. Several transit agencies in the San Francisco Bay Area are participating in demonstrating the largest single fleet of fuel cell buses in the United States.

  5. Influence of nanotopography on periodontal ligament stem cell functions and cell sheet based periodontal regeneration

    Directory of Open Access Journals (Sweden)

    Gao H

    2015-06-01

    Full Text Available Hui Gao,1–3,* Bei Li,1,2,* Lingzhou Zhao,4 Yan Jin1,21State Key Laboratory of Military Stomatology, Center for Tissue Engineering, School of Stomatology, The Fourth Military Medical University, 2Research and Development Center for Tissue Engineering, The Fourth Military Medical University, Xi’an, Shaanxi, 3Department of Stomatology, PLA 309th Hospital, Beijing, 4State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi’an, Shaanxi, People’s Republic of China*These authors contributed equally to this workAbstract: Periodontal regeneration is an important part of regenerative medicine, with great clinical significance; however, the effects of nanotopography on the functions of periodontal ligament (PDL stem cells (PDLSCs and on PDLSC sheet based periodontal regeneration have never been explored. Titania nanotubes (NTs layered on titanium (Ti provide a good platform to study this. In the current study, the influence of NTs of different tube size on the functions of PDLSCs was observed. Afterward, an ectopic implantation model using a Ti/cell sheets/hydroxyapatite (HA complex was applied to study the effect of the NTs on cell sheet based periodontal regeneration. The NTs were able to enhance the initial PDLSC adhesion and spread, as well as collagen secretion. With the Ti/cell sheets/HA complex model, it was demonstrated that the PDLSC sheets were capable of regenerating the PDL tissue, when combined with bone marrow mesenchymal stem cell (BMSC sheets and HA, without the need for extra soluble chemical cues. Simultaneously, the NTs improved the periodontal regeneration result of the ectopically implanted Ti/cell sheets/HA complex, giving rise to functionally aligned collagen fiber bundles. Specifically, much denser collagen fibers, with abundant blood vessels as well as cementum-like tissue on the Ti surface, which well-resembled the structure of natural PDL

  6. The number of FoxP3+ cells in transbronchial lung allograft biopsies does not predict bronchiolitis obliterans syndrome within the first five years after transplantation

    DEFF Research Database (Denmark)

    Krustrup, Dorrit; Iversen, Martin; Martinussen, Torben;

    2015-01-01

    Background: An important limitation to the success of lung transplantation is the development of bronchiolitis obliterans syndrome (BOS). It has been hypothesized that regulatory T lymphocytes (Tregs) are related to the risk of BOS. We aim to evaluate whether the number of forkhead box P3 (FoxP3......+) cells/mm2 in lung allograft biopsies is a predictor of long-term outcome. Materials and Methods: A total of 58 consecutive lung transplant patients were included in the study. For 233 routine surveillance biopsy samples, the numbers of FoxP3+ cells/mm2 were assessed by immunohistochemical staining...... with antibodies against FoxP3. BOS scores were calculated for the first five yr after transplantation. Results: We determined that acute rejection was related to the time elapsed from transplantation to BOS with hazard ratios of 3.18 (p = 0.02) and 3.73 (p = 0.04) when comparing the levels of acute rejection...

  7. Type I and II Diabetic Adipose-Derived Stem Cells Respond In Vitro to Dehydrated Human Amnion/Chorion Membrane Allograft Treatment by Increasing Proliferation, Migration, and Altering Cytokine Secretion

    OpenAIRE

    Massee, Michelle; Chinn, Kathryn; Lim, Jeremy J; Godwin, Lisa; Young, Conan S.; Koob, Thomas J.

    2016-01-01

    Objective: Human amniotic membranes have been shown to be effective for healing diabetic foot ulcers clinically and to regulate stem cell activity in vitro and in vivo; however, diabetic stem cells may be impaired as a sequela of the disease. In this study, dehydrated human amnion/chorion membrane (dHACM) allografts (EpiFix®; MiMedx Group) were evaluated for their ability to regulate diabetic stem cells in vitro. Approach: Human adipose-derived stem cells (ADSCs) from normal, type I diabetic,...

  8. The use of osteochondral allograft with bone marrow-derived mesenchymal cells and hinge joint distraction in the treatment of post-collapse stage of osteonecrosis of the femoral head.

    Science.gov (United States)

    Gagala, J; Tarczynska, M; Gaweda, K; Matuszewski, L

    2014-09-01

    Osteonecrosis of the femoral head is an entity which occurs mainly in young and active patients aged between 20 and 50. The success of hip joint preserving treatments ranges from 15% to 50% depending on the stage and amount of osteonecrotic lesion. Total hip replacement is indicated in late post-collapse hips but it has unsatisfactory survival because of the wear and osteolysis in young and active patients. Osteochondral allografts have been reported in the treatment of large articular lesions with defects in underlying bone in knee, talus and shoulder. By combining osteoconductive properties of osteochondral allograft with osteogenic abilities of bone marrow-derived mesenchymal cells it has a potential to be an alternative to an autologous graft. The adjunct of hinged joint distraction should minimize stresses in subchondral bone to promote creeping substitution and prevent femoral head collapse. Unlike current treatment modalities, it would provide both structural support and allow bony and articular substitution.

  9. Biological effects of rAAV-caAlk2 coating on structural allograft healing

    DEFF Research Database (Denmark)

    Koefoed, Mette; Ito, Hiromu; Gromov, Kirill

    2005-01-01

    coating induced endochondral bone formation directly on the cortical surface of the allograft by day 14. By day 28 there was evidence of remodeling of the new woven bone and massive osteoclastic resorption of the cortical surface of the rAAV-caAlk2-coated allografts only. Micro-CT analysis of r......Structural bone allografts often fracture due to their lack of osteogenic and remodeling potential. To overcome these limitations, we utilized allografts coated with recombinant adeno-associated virus (rAAV) that mediate in vivo gene transfer. Using beta-galactosidase as a reporter gene, we show...... that 4-mm murine femoral allografts coated with rAAV-LacZ are capable of transducing adjacent inflammatory cells and osteoblasts in the fracture callus following transplantation. While this LacZ vector had no effect on allograft healing, bone morphogenetic protein signals delivered via rAAV-caAlk2...

  10. Oxygen plasma-treated thermoresponsive polymer surfaces for cell sheet engineering.

    Science.gov (United States)

    Shimizu, Kazunori; Fujita, Hideaki; Nagamori, Eiji

    2010-06-01

    Although cell sheet tissue engineering is a potent and promising method for tissue engineering, an increase of mechanical strength of a cell sheet is needed for easy manipulation of it during transplantation or 3D tissue fabrication. Previously, we developed a cell sheet-polymer film complex that had enough mechanical strength that can be manipulated even by tweezers (Fujita et al., 2009. Biotechnol Bioeng 103(2): 370-377). We confirmed the polymer film involving a temperature sensitive polymer and extracellular matrix (ECM) proteins could be removed by lowering temperature after transplantation, and its potential use in regenerative medicine was demonstrated. However, the use of ECM proteins conflicted with high stability in long-term storage and low cost. In the present study, to overcome these drawbacks, we employed the oxygen plasma treatment instead of using the ECM proteins. A cast and dried film of thermoresponsive poly-N-isopropylacrylamide (PNIPAAm) was fabricated and treated with high-intensity oxygen plasma. The cells became possible to adhere to the oxygen plasma-treated PNIPAAm surface, whereas could not to the inherent surface of bulk PNIPAAm without treatment. Characterizations of the treated surface revealed the surface had high stability. The surface roughness, wettability, and composition were changed, depending on the plasma intensity. Interestingly, although bulk PNIPAAm layer had thermoresponsiveness and dissolved below lower critical solution temperature (LCST), it was found that the oxygen plasma-treated PNIPAAm surface lost its thermoresponsiveness and remained insoluble in water below LCST as a thin layer. Skeletal muscle C2C12 cells could be cultured on the oxygen plasma-treated PNIPAAm surface, a skeletal muscle cell sheet with the insoluble thin layer could be released in the medium, and thus the possibility of use of the cell sheet for transplantation was demonstrated.

  11. Spleen tyrosine kinase contributes to acute renal allograft rejection in the rat.

    Science.gov (United States)

    Ramessur Chandran, Sharmila; Tesch, Greg H; Han, Yingjie; Woodman, Naomi; Mulley, William R; Kanellis, John; Blease, Kate; Ma, Frank Y; Nikolic-Paterson, David J

    2015-02-01

    Kidney allografts induce strong T-cell and antibody responses which mediate acute rejection. Spleen tyrosine kinase (Syk) is expressed by most leucocytes, except mature T cells, and is involved in intracellular signalling following activation of the Fcγ-receptor, B-cell receptor and some integrins. A role for Syk signalling has been established in antibody-dependent native kidney disease, but little is known of Syk in acute renal allograft rejection. Sprague-Dawley rats underwent bilateral nephrectomy and received an orthotopic Wistar renal allograft. Recipient rats were treated with a Syk inhibitor (CC0482417, 30 mg/kg/bid), or vehicle, from 1 h before surgery until being killed 5 days later. Vehicle-treated recipients developed severe allograft failure with marked histologic damage in association with dense leucocyte infiltration (T cells, macrophages, neutrophils and NK cells) and deposition of IgM, IgG and C3. Immunostaining identified Syk expression by many infiltrating leucocytes. CC0482417 treatment significantly improved allograft function and reduced histologic damage, although allograft injury was still clearly evident. CC0482417 failed to prevent T-cell infiltration and activation within the allograft. However, CC0482417 significantly attenuated acute tubular necrosis, infiltration of macrophages and neutrophils and thrombosis of peritubular capillaries. In conclusion, this study identifies a role for Syk in acute renal allograft rejection. Syk inhibition may be a useful addition to T-cell-based immunotherapy in renal transplantation.

  12. Monosaccharide-responsive phenylboronate-polyol cell scaffolds for cell sheet and tissue engineering applications.

    Directory of Open Access Journals (Sweden)

    Rachamalla Maheedhar Reddy

    Full Text Available Analyte-responsive smart polymeric materials are of great interest and have been actively investigated in the field of regenerative medicine. Phenylboronate containing copolymers form gels with polyols under alkaline conditions. Monosaccharides, by virtue of their higher affinity towards boronate, can displace polyols and solubilize such gels. In the present study, we investigate the possibility of utilizing phenylboronate-polyol interactions at physiological pH in order to develop monosaccharide-responsive degradable scaffold materials for systems dealing with cells and tissues. Amine assisted phenylboronate-polyol interactions were employed to develop novel hydrogel and cryogel scaffolds at neutral pH. The scaffolds displayed monosaccharide inducible gel-sol phase transformability. In vitro cell culture studies demonstrated the ability of scaffolds to support cell adhesion, viability and proliferation. Fructose induced gel degradation is used to recover cells cultured on the hydrogels. The cryogels displayed open macroporous structure and superior mechanical properties. These novel phase transformable phenylboronate-polyol based scaffolds displayed a great potential for various cell sheet and tissue engineering applications. Their monosaccharide responsiveness at physiological pH is very useful and can be utilized in the fields of cell immobilization, spheroid culture, saccharide recognition and analyte-responsive drug delivery.

  13. Semi-mature MyD88-silenced bone marrow dendritic cells prolong the allograft survival in a rat model of intestinal transplantation

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-jun; MENG Song; Zhu Chun-fu; JIANG Hong; WU Wen-xi

    2011-01-01

    Background Semi-mature dendritic cells (DCs) may induce tolerance rather than immunity.However,little is known about the regulatory mechanism by which these DCs induce transplant tolerance.Myeloid differentiation factor 88 (MyD88) is a key adaptor of Toil-like receptor signaling,which plays a critical role in DC maturation.Activation of MyD88-silenced immature DCs results in the generation of semi-mature DCs.We explored the possibility of using these DCs to induce intestinal transplant tolerance in rats.Methods MyD88 expression was silenced in bone marrow DCs (F344 rats) using small interfering RNAs for 24 hours,at which point,lipopolysaccharide (LPS) was added to the culture for another 48 hours.These cells were analyzed for their in vitro and in vivo tolerizing capacities.Results Semi-mature DCs expressing moderate levels of MHC class Ⅱ and low levels of co-stimulatory molecules were found to produce interleukin (IL)-10,while IL-12 production was decreased.In vitro co-culture with completely allogeneic T cells from Wistar rats led to a significant decrease in alloreactive T-cell responses.In vivo,the transfer of semi-mature DCs (1×106 ceils) followed by the transplantation of fully mismatched intestinal grafts (F344 rats) led to significantly prolonged survival compared to rats receiving immature and mature DCs.Serum from semi-mature DC-treated rats contained lower concentrations of the pro-inflammatory cytokines IL-2 and interferon-Y 5 days after transplantation.Conclusion Semi-mature DCs may promote inducible allograft tolerance and this study suggests a new strategy by which to facilitate the induction of transplant tolerance.

  14. Autologous preconditioned mesenchymal stem cell sheets improve left ventricular function in a rabbit old myocardial infarction model

    Science.gov (United States)

    Tanaka, Yuya; Shirasawa, Bungo; Takeuchi, Yuriko; Kawamura, Daichi; Nakamura, Tamami; Samura, Makoto; Nishimoto, Arata; Ueno, Koji; Morikage, Noriyasu; Hosoyama, Tohru; Hamano, Kimikazu

    2016-01-01

    Mesenchymal stem cells (MSCs) constitute one of the most powerful tools for therapeutic angiogenesis in infarcted hearts. However, conventional MSC transplantation approaches result in insufficient therapeutic effects due to poor retention of graft cells in severe ischemic diseases. Cell sheet technology has been developed as a new method to prolong graft cell retention even in ischemic tissue. Recently, we demonstrated that hypoxic pretreatment enhances the therapeutic efficacy of cell sheet implantation in infarcted mouse hearts. In this study, we investigated whether hypoxic pretreatment activates the therapeutic functions of bone marrow-derived MSC (BM-MSC) sheets and improves cardiac function in rabbit infarcted hearts following autologous transplantation. Production of vascular endothelial growth factor (VEGF) was increased in BM-MSC monolayer sheets and it peaked at 48 h under hypoxic culture conditions (2% O2). To examine in vivo effects, preconditioned autologous BM-MSC sheets were implanted into a rabbit old myocardial infarction model. Implantation of preconditioned BM-MSC sheets accelerated angiogenesis in the peri-infarcted area and decreased the infarcted area, leading to improvement of the left ventricular function of the infarcted heart. Importantly, the therapeutic efficacy of the preconditioned BM-MSC sheets was higher than that of standardly cultured sheets. Thus, implantation of autologous preconditioned BM-MSC sheets is a feasible approach for enhancing therapeutic angiogenesis in chronically infarcted hearts. PMID:27347329

  15. No red cell alloimmunization or change of clinical outcome after using fresh frozen cancellous allograft bone for acetabular reconstruction in revision hip arthroplasty: a follow up study

    Directory of Open Access Journals (Sweden)

    Mittag Falk

    2012-09-01

    Full Text Available Abstract Background Possible immunization to blood group or other antigens and subsequent inhibition of remodeling or incorporation after use of untreated human bone allograft was described previously. This study presents the immunological, clinical and radiological results of 30 patients with acetabular revisions using fresh frozen non-irradiated bone allograft. Methods AB0-incompatible (donor-recipient bone transplantation was performed in 22 cases, Rh(D incompatible transplantation in 6 cases. The mean follow up of 23 months included measuring Harris hip score and radiological examination with evaluation of remodeling of the bone graft, implant migration and heterotopic ossification. In addition, all patients were screened for alloimmunization to Rh blood group antigens. Results Compared to the whole study group, there were no differences in clinical or radiological measurements for the groups with AB0- or Rh(D-incompatible bone transplantation. The mean Harris Hip Score was 80.6. X-rays confirmed total remodeling of all allografts with no acetabular loosening. At follow up, blood tests revealed no alloimmunization to Rh blood group donor antigens. Conclusions The use of fresh frozen non-irradiated bone allograft in acetabular revision is a reliable supplement to reconstruction. The risk of alloimmunization to donor-blood group antigens after AB0- or Rh-incompatible allograft transplantation with a negative long-term influence on bone-remodeling or the clinical outcome is negligible.

  16. Ex vivo expanded human regulatory T cells delay islet allograft rejection via inhibiting islet-derived monocyte chemoattractant protein-1 production in CD34+ stem cells-reconstituted NOD-scid IL2rγnull mice.

    Directory of Open Access Journals (Sweden)

    Fang Xiao

    Full Text Available Type 1 diabetes mellitus (T1DM is an autoimmune disease caused by immune-mediated destruction of insulin-secreting β cells of the pancreas. Near complete dependence on exogenous insulin makes T1DM very difficult to control, with the result that patients are exposed to high blood glucose and risk of diabetic complications and/or intermittent low blood glucose that can cause unconsciousness, fits and even death. Allograft transplantation of pancreatic islets restores normoglycemia with a low risk of surgical complications. However, although successful immediately after transplantation, islets are progressively lost, with most of the patients requiring exogenous insulin within 2 years post-transplant. Therefore, there is an urgent requirement for the development of new strategies to prevent islet rejection. In this study, we explored the importance of human regulatory T cells in the control of islets allograft rejection. We developed a pre-clinical model of human islet transplantation by reconstituting NOD-scid IL2rγnull mice with cord blood-derived human CD34+ stem cells and demonstrated that although the engrafted human immune system mediated the rejection of human islets, their survival was significantly prolonged following adoptive transfer of ex vivo expanded human Tregs. Mechanistically, Tregs inhibited the infiltration of innate immune cells and CD4+ T cells into the graft by down-regulating the islet graft-derived monocyte chemoattractant protein-1. Our findings might contribute to the development of clinical strategies for Treg therapy to control human islet rejection. We also show for the first time that CD34+ cells-reconstituted NOD-scid IL2rγnull mouse model could be beneficial for investigating human innate immunity in vivo.

  17. A silicon sheet casting experiment. [for solar cell water production

    Science.gov (United States)

    Bickler, D. B.; Sanchez, L. E.; Sampson, W. J.

    1980-01-01

    The casting of silicon blanks for solar cells directly without slicing is an exciting concept. An experiment was performed to investigate the feasibility of developing a machine that casts wafers directly. A Czochralski furnace was modified to accept a graphite ingot-simulating fixture. Silicon was melted in the middle of the ingot simulator in a boron nitride mold. Sample castings showed reasonable crystal size. Solar cells were made from the cast blanks. The performance is reported.

  18. Engineered bone marrow-derived cell sheets restore structure and function of radiation-injured rat urinary bladders.

    Science.gov (United States)

    Imamura, Tetsuya; Ogawa, Teruyuki; Minagawa, Tomonori; Yokoyama, Hitoshi; Nakazawa, Masaki; Nishizawa, Osamu; Ishizuka, Osamu

    2015-05-01

    Previously, we reported that implantation of isolated single bone marrow-derived cells into radiation-injured urinary bladders could restore structure and function. However, injections of isolated single cells had some limitations. Thus, in this study, we produced bone marrow-derived cell sheets in temperature-responsive culture dishes that release the monolayer sheets intact. We then determined whether the produced cell sheets could restore function to irradiated urinary bladders. Twenty female 10-week-old Sprague-Dawley (SD) rats were irradiated with 2 gray once a week for 5 weeks. Bone marrow cells harvested from two male 17-week-old green fluorescence protein-transfected SD rats were placed in primary culture for 7 days. Bone marrow cell-derived outgrowths were harvested by enzymatic digestion and transferred into the atelocollagen-coated temperature-responsive culture dishes for 2 days. To harvest the secondarily cultured cells as monolayer sheets, a support membrane was put in each culture dish, and then the temperature was reduced to 20°C. Each released cell sheet was then patched onto the irradiated anterior bladder wall (n=10). As controls, cell-free sheets were similarly patched (n=10). After 4 weeks, transplanted cells were detected on the bladder walls. The cell sheet-transplanted bladders had smooth muscle layers and acetylcholinesterase-positive nerve fibers in proportions that were significantly larger than those of the control bladders. In addition, the cell sheet-transplanted bladders had reduced prolyl 4-hydroxylase beta (P4HB)-positive regions of collagen synthesis and apoptosis within the smooth muscle layers. In cystometric investigations, threshold pressures, voiding interval, micturition volume, and bladder capacity in the cell sheet-transplantation group were significantly higher than those in the control group. Residual volume of the cell sheet-transplantation group was significantly lower compared with the control. There were 24 growth

  19. Radionuclide diagnosis of allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    George, E.A.

    1982-10-01

    Interaction with one or more anatomical and physiopathological characteristics of the rejecting renal allograft is suggested by those radioagents utilized specifically for the diagnosis of allograft rejection. Rejection, the most common cause of declining allograft function, is frequently mimicked clinically or masked by other immediate or long term post transplant complications. Understanding of the anatomical pathological features and kinetics of rejection and their modification by immunosuppressive maintenance and therapy are important for the proper clinical utilization of these radioagents. Furthermore, in selecting these radionuclides, one has to consider the comparative availability, preparatory and procedural simplicity, acquisition and display techniques and the possibility of timely report. The clinical utilities of radiofibrinogen, /sup 99m/Tc sulfur colloid and /sup 67/Ga in the diagnosis of allograft rejection have been evaluated to a variable extent in the past. The potential usefulness of the recently developed preparations of /sup 111/In labeled autologous leukocytes and platelets are presently under investigation.

  20. Avidin-biotin-based approach to forming heterotypic cell clusters and cell sheets on a gas-permeable membrane

    Energy Technology Data Exchange (ETDEWEB)

    Hamon, M; Ozawa, T; Montagne, K; Kojima, N; Ishii, R; Sakai, Y [Institute of Industrial Science (IIS), University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505 (Japan); Yamaguchi, S; Nagamune, T [Department of Bioengineering, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Ushida, T, E-mail: mzh0026@auburn.edu [Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2011-09-15

    Implantation of sheet-like liver tissues is a promising method in hepatocyte-based therapies, because angiogenesis is expected to occur upon implantation from the surrounding tissues. In this context, we introduce here a new methodology for the formation of a functional thick hepatic tissue usable for cell sheet technology. First, we report the formation of composite tissue elements in suspension culture. Composite elements were composed of human hepatoma Hep G2 cells and mouse NIH/3T3 fibroblasts which are important modulators for thick-tissue formation. To overcome the very low attachment and organization capability between different cells in suspension, we synthesized a new cell-to-cell binding molecule based on the avidin-biotin binding system that we previously applied to attach hepatocytes on artificial substrata. This newly synthesized biotin-conjugated biocompatible anchoring molecule was inserted in the plasma membrane of both cell types. NIH/3T3 cells were further conjugated with avidin and incubated with biotin-presenting Hep G2 cells to form highly composite tissue elements. Then, we seeded those elements on highly gas-permeable membranes at their closest packing density to induce the formation of a thick, composite, functional hepatic tissue without any perfusion. This methodology could open a new way to engineer implantable thick liver tissue sheets where different cell types are spatially organized and well supplied with oxygen.

  1. Human allogeneic CD2+lymphocytes activate airway-derived epithelial cells to produce interleukin-6 and interleukin-8. Possible role for the epithelium in chronic allograft rejection

    NARCIS (Netherlands)

    Borger, P; Kauffman, HF; Scholma, J; Timmerman, JAB; Koeter, GH

    2002-01-01

    Background: The adhesion of lymphocytes to the epithelium and the release of proinflammatory cytokines are important features observed during acute and chronic allograft rejection. Development of chronic rejection in lung-transplantation patients is preceded by high levels of interleukin (IL)-6 and

  2. A surgical robot with a heart-surface-motion synchronization mechanism for myoblast cell sheet transplantation.

    Science.gov (United States)

    Xu, Kangyi; Nakamura, Ryoichi

    2013-01-01

    Myoblast cell sheets are employed in the clinical treatment of heart disorders. We propose a surgical robot system with two endoscopic cameras, characterized by a double remote center of motion (RCM) mechanism, to realize heart-surface-motion synchronization movement for myoblast cell sheet transplantation on a beating heart surface. A robot system with the double RCM mechanism was developed for which the linear and rotation motions are totally isolated, and an experiment was conducted to evaluate the tracking accuracy of the robot system when tracking a randomly moving target. The tracking data were updated with a Polaris system at 30 Hz. The experiment results showed linear and rotation tracking errors of 4.93 ± 5.92 mm and 2.54 ± 5.44°, respectively.

  3. N-octanoyl Dopamine Attenuates the Development of Transplant Vasculopathy in Rat Aortic Allografts Via Smooth Muscle Cell Protective Mechanisms

    NARCIS (Netherlands)

    Wedel, Johannes; Hottenrott, Maximilia C.; Bulthuis, Marian; Huitema, Sippie; Yard, Benito A.; Hillebrands, Jan-Luuk

    2016-01-01

    Background Transplant vasculopathy (TV) is a major cause for late graft loss after cardiac transplantation. Endothelial damage and T cell infiltration play a pivotal role in the development of TV. Because N-octanoyl dopamine (NOD) inhibits vascular inflammation and suppresses T cell activation in vi

  4. SUBSTRATE MATERIALS FOR POLY-CSiTF SOLAR CELLS:OPTIMIZATION OF SILICON SHEET FROM POWDER

    Institute of Scientific and Technical Information of China (English)

    Q. Ban; H. Shen; X.J. Wang; X.W. Zou; Z.C. Liang

    2005-01-01

    The optimization of silicon sheet from powder (SSP) technology as polycrystalline silicon thin film (poly-CSiTF) solar cells' substrate materials is studied by orthogonal design experimental method. Based on technological optimization of SSP prepared from electronic grade silicon powder, SSP solar cell devices with simple structure are prepared and the effect of SSP substrate is discussed. Up to now, the conversion efficiency of the prepared solar cells on low purity SSP substrate with fundamental structure has reached 8.25% (with area of 1 cm×1 cm).

  5. The value of urine cytologic examination findings in the diagnosis of the acute renal allograft rejection

    Directory of Open Access Journals (Sweden)

    Tatomirović Željka

    2003-01-01

    Full Text Available Background. Acute rejection of allograft is one of the most serious complications of renal transplantation that requires fast and precise diagnostic approach. In this paper our experience in cytologic urinalysis as a diagnostic method of the acute renal allograft rejection was reviewed. Methods. The study group included 20 of 56 patients with transplanted kidneys who were assumed for the acute allograft rejection according to allograft dysfunction and/or urine cytology findings. Histological findings confirmed allograft rejection in 4 patients. Urine sediment obtained in cytocentrifuge was air-dried and stained with May-Grunwald-Giemsa. Acute allograft rejection was suspected if in 10 fields under high magnification 15 or more lymphocytes with renal tubular cells were found. Results. Acute transplant rejection occured in 32.1% patients. In 15 patients clinical findings of the acute renal allograft rejection corresponded with cytological and histological findings (in the cases in which it was performed. Three patients with clinical signs of the acute allograft rejection were without cytological confirmation, and in 2 patients cytological findings pointed to the acute rejection, but allograft dysfunction was of different etiology (acute tubular necrosis, cyclosporine nephrotoxicity. In patients with clinical, cytological and histological findings of the acute allograft rejection urine finding consisted of 58% lymphocytes, 34% neutrophilic leucocytes and 8% monocytes/macrophages on the average. The accuracy of cytologic urinalysis related to clinical and histological finding was 75%. Conclusion. Urine cytology as the reliable noninvasive, fast and simple method is appropriate as the a first diagnostic line of renal allograft dysfunction, as well as for monitoring of the graft function.

  6. Development of transplant vasculopathy in aortic allografts correlates with neointimal smooth muscle cell proliferative capacity and fibrocyte frequency

    NARCIS (Netherlands)

    Onuta, Geanina; van Ark, Joris; Rienstra, Heleen; Boer, Mark Walther; Klatter, Flip A.; Bruggeman, Cathrien A.; Zeebregts, Clark J.; Rozing, Jan; Hillebrands, Jan-Luuk

    2010-01-01

    Objective: Transplant vasculopathy consists of neointima formation in graft vasculature resulting from vascular smooth muscle cell recruitment and proliferation. Variation in the severity of vasculopathy has been demonstrated. Genetic predisposition is suggested as a putative cause of this variation

  7. Long-term follow-up of kidney allografts in patients with sickle cell hemoglobinopathy Transplante renal na anemia falciforme

    OpenAIRE

    Friedrisch,João R.; Barros, Elvino J.; Roberto C. Manfro; Bittar,Cristhina M.; Silla,Lúcia M. R.

    2003-01-01

    Although sickle cell anemia and sickle cell disease produce a variety of functional renal abnormalities they uncommonly cause end stage renal failure. Renal transplantation has been a successful alternative for the treatment of the rare terminal chronic renal failure with outcomes comparable with non-sickle recipients. This approach, however, has not been often described on patients with renal failure associated with SC hemoglobinopathy. Here we report the outcomes of two patients with chroni...

  8. An Innovative Strategy for the Fabrication of Functional Cell Sheets Using an Electroactive Conducting Polymer.

    Science.gov (United States)

    Lee, HyungJae; Cho, Youngnam

    2015-01-01

    Here, we report the development of an electric field-assisted methodology for constructing 3D C2C12 cell sheets with the potential for cell surface modification. In this method, a conducting polymer, polypyrrole (Ppy), is electrodeposited via biotin doping, and then chemical conjugation of biotinylated bone morphogenetic protein 2 (BMP2) is achieved using a biotin-streptavidin cross-linker. Subsequently, C2C12 cells are cultured on BMP2-immobilized Ppy surfaces to induce interactions between cell surface receptors and bound BMP2 ligands. Following these procedures, layers of BMP2-immobilized cells can be easily detached from the Ppy surface by applying an electrical potential. This novel method results in high affinity, ligand-bound cell sheets, which exhibit homogeneous coverage with membrane-bound proteins and signal activation that occurs via maximal receptor accessibility. Using this strategy to engineer the cell surface with desirable ligands results in structures that mimic in vivo tissues; thus, the method reported here has potential applications in regenerative medicine and tissue engineering.

  9. 许旺细胞植入去细胞异体神经修复大鼠面神经缺损%Repair of facial nerve defects by using acellular nerve allografts implanted with Schwann cells in rats

    Institute of Scientific and Technical Information of China (English)

    朱国臣; 肖大江; 黄红宇; 袁渊; 吴四海; 赵新

    2008-01-01

    目的 观察体外分离、培养的许旺细胞对去细胞异体神经修复面神经长距离缺损的促进作用. 方法 30只大鼠随机分成A组、B组和c组(每组10只),制成而神经缺损12 mm模型,分别以去细胞异体神经联合许旺细胞、去细胞异体神经和自体神经移植修复.术后5个月分别行神经电生理、再生神经形态及数量等检测. 结果 A组神经肌肉动作电位的波幅恢复率(术侧/健侧)为(35.8±2.5)%,潜伏期恢复率(健侧/术侧)为(65.8±2.9)%;神经移植段再生轴突数为(1 570±188)个,髓鞘厚度为(0.383±0.031)μm.A组的各项指标优于B组(P0.05). 结论 许旺细胞植入去细胞异体神经可促进面神经长距离缺损的修复.%Objective To observe the effects of in vitro isolated Schwann cells co-cultured with chemically acellular nerve allografts on improving repair of large facial nerve defects. Methods A total of 30 Wistar rats were equally randomized into three groups, ie, experimental group, allograft group and autograft group. Nerve defect of 12 mm in length was made in the left inferior buccal branch of facial nerve and repaired with acellular nerve allograft implanted with Schwann cells, acellular nerve allograft and fresh tibial nerve autograft respectively. At the 5th month postoperatively, the function and morpholo-gy of the regenerated nerves were observed by electrophysiological method, methylene blue staining and transmission electron microscope. Results In experimental group, the recovery rate (operation side/normal side) of amplitude of nerve-muscle action potential was (35.8±2.5)%, the lantency recovery rate (normal side/operation side) (65.8±2.9)%, the number of the regenerated axon 1 570±188 and the myelin thickness (0.383±0.031) μm. The results in the experimental group were significantly supe-rior to those in the acellular nerve allograft group (P 0.05). Conclusion Transplantation of Schwarm cells in acellular nerve allograft can im

  10. VITAL COMPUTER MORPHOMETRY OF LIMPHOCYTES IN DIAGNOSIS OF ACUTE RENAL ALLOGRAFT REJECTION

    Directory of Open Access Journals (Sweden)

    A. V. Vatazin

    2009-01-01

    Full Text Available The article focuses on the results of the investigation of peripheral blood lymphocyte morphofunctional status in healthy volunteers and renal allograft recipients for early postoperative period. Working out noninvasive tests for diagnosis of acute renal allograft rejection based on the measuring of cell morphometric parameters by method of coherent phase microscopy (CPM. It was found out that the lymphocyte phase height was proportional cell image density and its geometrical thickness. Our results showed that the variations of immunocompetent cell morphometric indicants can be in advance the dynamics of blood creatine increasing and answer for early criteria of acute renal allograft rejection. 

  11. Thermo-responsive methylcellulose hydrogels as temporary substrate for cell sheet biofabrication.

    Science.gov (United States)

    Altomare, Lina; Cochis, Andrea; Carletta, Andrea; Rimondini, Lia; Farè, Silvia

    2016-05-01

    Methylcellulose (MC), a water-soluble polymer derived from cellulose, was investigated as a possible temporary substrate having thermo-responsive properties favorable for cell culturing. MC-based hydrogels were prepared by a dispersion technique, mixing MC powder (2, 4, 6, 8, 10, 12 % w/v) with selected salts (sodium sulphate, Na2SO4), sodium phosphate, calcium chloride, or phosphate buffered saline, to evaluate the influence of different compositions on the thermo-responsive behavior. The inversion test was used to determine the gelation temperatures of the different hydrogel compositions; thermo-mechanical properties and thermo-reversibility of the MC hydrogels were investigated by rheological analysis. Gelation temperatures and rheological behavior depended on the MC concentration and type and concentration of salt used in hydrogel preparation. In vitro cytotoxicity tests, performed using L929 mouse fibroblasts, showed no toxic release from all the tested hydrogels. Among the investigated compositions, the hydrogel composed of 8 % w/v MC with 0.05 M Na2SO4 had a thermo-reversibility temperature at 37 °C. For that reason, this formulation was thus considered to verify the possibility of inducing in vitro spontaneous detachment of cells previously seeded on the hydrogel surface. A continuous cell layer (cell sheet) was allowed to grow and then detached from the hydrogel surface without the use of enzymes, thanks to the thermo-responsive behavior of the MC hydrogel. Immunofluorescence observation confirmed that the detached cell sheet was composed of closely interacting cells.

  12. Nephron-Sparing Surgery for Adenocarcinoma in a Renal Allograft

    Directory of Open Access Journals (Sweden)

    Fernando Vázquez Alonso

    2012-01-01

    Full Text Available The incidence of malignant tumors in recipients of renal allografts is higher than in the general population. Renal cell carcinoma (RCC accounts for 4.6% of the tumors in transplanted patients; of them, only 10% are found in transplanted kidneys. Transplantectomy has always been the usual treatment. However, during the last years, nephron-sparing surgery of the allograft is more frequently done in well-selected cases, and therefore dialysis can be avoided. We report the case of a 37-year-old female patient with renal transplant, diagnosed with a 4.5 cm tumor in the lower pole of the renal allograft. The patient underwent partial nephrectomy successfully. Six years after surgery, there is no evidence of recurrence of the disease and the patient maintains an adequate renal function.

  13. Nephron-Sparing Surgery for Adenocarcinoma in a Renal Allograft

    Science.gov (United States)

    Vázquez Alonso, Fernando; Cardozo Rodríguez, Enrique; Puche Sanz, Ignacio; Flores Martin, Jose Francisco; Molina Hernandez, Jose Miguel; Berrio Campos, Raquel; Vicente Prados, Javier; Medina Benitez, Antonio; Cózar Olmo, Jose Manuel

    2012-01-01

    The incidence of malignant tumors in recipients of renal allografts is higher than in the general population. Renal cell carcinoma (RCC) accounts for 4.6% of the tumors in transplanted patients; of them, only 10% are found in transplanted kidneys. Transplantectomy has always been the usual treatment. However, during the last years, nephron-sparing surgery of the allograft is more frequently done in well-selected cases, and therefore dialysis can be avoided. We report the case of a 37-year-old female patient with renal transplant, diagnosed with a 4.5 cm tumor in the lower pole of the renal allograft. The patient underwent partial nephrectomy successfully. Six years after surgery, there is no evidence of recurrence of the disease and the patient maintains an adequate renal function. PMID:22848857

  14. The experimental observation on the repairing spinal cord injury by olfactory ensheathing cells allograft of different sources

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objecttive To observe the repaired effect of distinct source olfactory ensheathing cells (OECs) on spinal cord injury (SCI) rats. Methods These OECs were dissociated from olfactory bulb and olfactory mucosa of SD rats and transplanted to the injuried region of spinal cord injury rats. The function of nerve, motor evoked potential of hind legs and the histopathlogical diversities of injuried spinal cord were observed. Results The OECs grafts into the SCI area could survive longer time. The BBB scale, incubat...

  15. Host-Derived Smooth Muscle Cells Accumulate in Cardiac Allografts: Role of Inflammation and Monocyte Chemoattractant Protein 1

    OpenAIRE

    Piotr Religa; Grudzinska, Monika K; Krzysztof Bojakowski; Joanna Soin; Jerzy Nozynski; Michal Zakliczynski; Zbigniew Gaciong; Marian Zembala; Cecilia Söderberg-Nauclér

    2009-01-01

    Transplant arteriosclerosis is characterized by inflammation and intimal thickening caused by accumulation of smooth muscle cells (SMCs) both from donor and recipient. We assessed the relationship between clinical factors and the presence of host-derived SMCs in 124 myocardial biopsies from 26 consecutive patients who received hearts from opposite-sex donors. Clinical and demographic information was obtained from the patients' medical records. Host-derived SMCs accounted for 3.35+/-2.3% of ce...

  16. Las células T reguladoras y su influencia en la sobrevida del trasplante renal Regulatory T cells and their influence in kidney allograft survival

    Directory of Open Access Journals (Sweden)

    Sonia Y. Velásquez

    2007-10-01

    Full Text Available La respuesta inmune desencadenada frente a un trasplante alogénico conduce usualmente a una respuesta efectora que resulta en el rechazo del aloinjerto; sin embargo, algunos individuos mantienen un trasplante funcionante a largo plazo sin signos de rechazo (tolerancia operacional, aun en ausencia de inmunosupresión. Se ha sugerido que los mismos mecanismos son responsables para la tolerancia hacia antígenos propios y aloantígenos. Uno de estos mecanismos es la regulación inmune y se han identificado varias subpoblaciones de células con propiedades reguladoras. Entre ellas, la población celular mejor caracterizada corresponde a las células T reguladoras (Tregs. Aunque las Tregs en ratones son CD4+CD25+, en humanos el fenotipo de las Treg está restringida a las células T CD4 con alta expresión de CD25 (CD25high y del factor de transcripción Foxp3. El análisis fenotípico y funcional de las células T reguladoras o supresoras circulantes en pacientes trasplantados tal vez sea útil para la detección de pacientes tolerantes operacionales. Además, una futura manipulación in vitro de estas células con fines terapéuticos podría conducir a lograr la inducción de tolerancia in vivo en el trasplante clínico. Aquí, revisamos la evidencia experimental y clínica del papel de las células reguladoras en la biología del trasplante.The immune response elicited by an allogenic transplant usually leads to an effector response resulting in allograft rejection; however, some individuals maintain a long-term functioning transplant without signs of rejection (operational tolerance even in the absence of immunosuppression. It has been suggested that the same mechanisms are responsible for tolerance to self-antigens and alloantigens. One of such mechanisms is immune regulation and several cell subsets with regulatory properties have been identified. Among them, the best characterized cell populations are the regulatory T cells (Treg. Although

  17. Single objective light-sheet microscopy for high-speed whole-cell 3D super-resolution.

    Science.gov (United States)

    Meddens, Marjolein B M; Liu, Sheng; Finnegan, Patrick S; Edwards, Thayne L; James, Conrad D; Lidke, Keith A

    2016-06-01

    We have developed a method for performing light-sheet microscopy with a single high numerical aperture lens by integrating reflective side walls into a microfluidic chip. These 45° side walls generate light-sheet illumination by reflecting a vertical light-sheet into the focal plane of the objective. Light-sheet illumination of cells loaded in the channels increases image quality in diffraction limited imaging via reduction of out-of-focus background light. Single molecule super-resolution is also improved by the decreased background resulting in better localization precision and decreased photo-bleaching, leading to more accepted localizations overall and higher quality images. Moreover, 2D and 3D single molecule super-resolution data can be acquired faster by taking advantage of the increased illumination intensities as compared to wide field, in the focused light-sheet.

  18. The significance of cytologic examination of urine in the diagnosis of renal allograft dysfunction

    Directory of Open Access Journals (Sweden)

    Tatomirović Željka

    2003-01-01

    Full Text Available Background. This paper presents our experience with cytologic examination of urine in diagnosing renal allograft dysfunction. Methods. The study group included 23 patients with renal allograft dysfunction, selected from 56 patients who underwent renal transplantation. Etiologic diagnosis was made according to the clinical picture, histological findings during allograft biopsy, and cytologic examination of urine. Urine sediment was obtained in cytocentrifuge and was air dried and stained with May Grunwald Giemsa. Results. Out of 23 patients with allograft dysfunction in 18 (78.3% patient it was caused by acute rejection, and in 5 (8.9% patients by allograft infarction, cyclosporine nephrotoxicity, acute tubular necrosis and chronic nephropathy. In eighteen patients (78.3% cytologic examination of urine was pathologic, while in 16 (70% clinical and histology findings coincided with urine cytology findings. Out of 18 patients with acute allograft rejection in 15 patients cytologic examination of urine coincided with acute rejection. Out of 7 patients with expressed cyclosporine nephrotoxicity, in 5 cytologic examination of urine confirmed the cause of allograft dysfunction, as well as in one of 2 patients with acute tubular necrosis. Cytologic examination of urine indicated parenchymal damage in 2 patients with reccurent disease (membranoproliferative and focal sclerosing glomerulonephritis. In 4 of 5 patients suffering from chronic rejection in a year’s monitoring period, urine sediment periodically consisted of lymphocytes, neutrophilic leucocytes, monocyte/macrophages, tubular cells and cilindres, without the predominance of any cell type. In 3 patients allograft dysfunction was caused by infective agents (bacteria, fungus cytomegalovirus. Conclusion. Cytologic examination of urine might be an alternative to histological in diagnosing acute allograft rejection and acute tubular necrosis or nephtotoxicity. Also it might indicate parenchymal

  19. Initiated chemical vapor deposition of thermoresponsive poly(N-vinylcaprolactam) thin films for cell sheet engineering.

    Science.gov (United States)

    Lee, Bora; Jiao, Alex; Yu, Seungjung; You, Jae Bem; Kim, Deok-Ho; Im, Sung Gap

    2013-08-01

    Poly(N-vinylcaprolactam) (PNVCL) is a thermoresponsive polymer known to be nontoxic, water soluble and biocompatible. Here, PNVCL homopolymer was successfully synthesized for the first time by use of a one-step vapor-phase process, termed initiated chemical vapor deposition (iCVD). Fourier transform infrared spectroscopy results showed that radical polymerization took place from N-vinylcaprolactam monomers without damaging the functional caprolactam ring. A sharp lower critical solution temperature transition was observed at 31°C from the iCVD poly(N-vinylcaprolactam) (PNVCL) film. The thermoresponsive PNVCL surface exhibited a hydrophilic/hydrophobic alteration with external temperature change, which enabled the thermally modulated attachment and detachment of cells. The conformal coverage of PNVCL film on various substrates with complex topography, including fabrics and nanopatterns, was successfully demonstrated, which can further be utilized to fabricate cell sheets with aligned cell morphology. The advantage of this system is that cells cultured on such thermoresponsive surfaces could be recovered as an intact cell sheet by simply lowering the temperature, eliminating the need for conventional enzymatic treatments.

  20. NF-κB activation and zinc finger protein A20 expression in mature dendritic cells derived from liver allografts undergoing acute rejection

    Institute of Scientific and Technical Information of China (English)

    Ming-Qing Xu; Wei Wang; Lan Xue; Lv-Nan Yan

    2003-01-01

    AIM: To investigate the role of NF-κB activation and zinc finger protein A20 expression in the regulation of maturation of dendritic cells (DCs) derived from liver allografts undergoing acute rejection. METHODS: Sixty donor male SD rats and sixty recipient male LEW rats weighing 220-300 g were randomly divided into whole liver transplantation group and partial liver transplantation group. Allogeneic (SD rat to LEW rat) whole and 50 % partial liver transplantation were performed. DCs from liver grafts 0 hour and 4 days after transplantation were isolated and propagated in the presence of GM-CSF in vitro. Morphological characteristics and phenotypical features of DCs propagated for 10 days were analyzed by electron microscopy and flow cytometry, respectively. NF-κB binding activity, IL-12p70 protein and zinc finger protein A20expression in these DCs were measured by EMSA and Western blotting, respectively. Histological grading of rejection was determined. RESULTS: Allogeneic whole liver grafts showed no signs of rejection on day 4 after the transplantation. In contrast,allogeneic partial liver grafts demonstrated moderate to severe rejection on day 4 after the transplantation. After propagation for 10 days in the presence of GM-CSF in vitro,DCs from allogeneic whole liver grafts exhibited features of immature DC with absence of CD40 surface expression,these DCs were found to exhibit detectable but very low level of NF-κB activity, IL-12 p70 protein and zinc finger protein A20 expression. Whereas, DCs from allogeneic partial liver graft 4 days after transplantation displayed features of mature DC, with high level of CD40 surface expression, and as a consequence, higher expression of IL-12p70 protein, higher activities of NF-κB and higher expression of zinc finger protein A20 compared with those of DCs from whole liver grafts (P<0.001). CONCLUSION: These results suggest that A20expression is up-regulated in response to NF-κB activation in mature DCs derived from

  1. Transplant graft vasculopathy: an emerging target for prevention and treatment of renal allograft dysfunction.

    Science.gov (United States)

    Kang, Duk-Hee; Kang, Shin-Wook; Jeong, Hyeon Joo; Kim, Yu Seun; Yang, Chul Woo; Johnson, Richard J

    2004-12-31

    Maintenance of healthy endothelium is essential to vascular homeostasis, and preservation of endothelial cell function is critical for transplant allograft function. Damage of microvascular endothelial cells is now regarded as a characteristic feature of acute vascular rejection and chronic allograft nephropathy, which is an important predictor of graft loss and is often associated with transplant vasculopathy. In this review, we will discuss the role of microvascular endothelium, in renal allograft dysfunction, particularly as it relates to markers of endothelial dysfunction and endothelial repair mechanisms. We also discuss the potential for therapies targeting endothelial dysfunction and transplant graft vasculopathy.

  2. Modifying cyclosporine associated renal allograft dysfunction

    Directory of Open Access Journals (Sweden)

    Mohapatra N

    2009-01-01

    Full Text Available Transplantation is accepted therapy for chronic kidney disease. However the essential immuno-suppressive agents for graft survival have their own side-effects. Renal biopsy is a reliable tool for diagnosing cyclosporine (CsA nephrotoxicity. To present our observations on CsA toxicity in renal allograft biopsies, we studied prospectively 207 renal allograft biopsies performed for graft dysfunction as per Ahmedabad Tole-rance Induction Protocol (ATIP and compared them to 50 controls from January to October 2007. The ATIP comprised donor specific leucocyte infusions, low dose target specific irradiation; non-myeloablative condi-tioning with Anti-T ± B cell antibodies followed by intraportal administration of cultured donor bone marrow (BM ± adipose tissue derived mesenchymal stem cells. Renal transplantation was performed following nega-tive lymphocytotoxicity cross-matching. The post-transplant immunosuppressive agents included CsA 2.5 ± 0.5 mg/kg BW/day and prednisone 0.2 mg/kg BW/day. The controls were transplanted using standard triple immunosuppressive agents including CsA 5 ± 1 mg/Kg BW/day, prednisone 0.6 mg/kg BW/day, and MMF/ Azathioprine. The Institutional Review Board approved the ATIP. The biopsies were categorized into 2 groups; group A (N=97: performed < 6 months, group B (N= 160, > 6 months posttransplant. Acute CsA toxicity was observed in group A: 2.5% ATIP and 11.1% controls; group B: 16.2% ATIP and 8.8% controls. Chronic CsA toxicity was observed in group B: 10.8 % ATIP and 17.6 % controls. Acute toxicity was more in the ATIP, while chronic toxicity was more in the controls. CsA doses were reduced post-biopsy and resulted in improved graft function evaluated by serum creatinine. We conclude that CsA nephrotoxicity evaluated by allograft biopsy resulted in allograft function recovery by decreasing the cyclosporine dose, and the ATIP decreased the incidence of CsA nephrotoxicity.

  3. Epithelial sheet folding induces lumen formation by Madin-Darby canine kidney cells in a collagen gel.

    Directory of Open Access Journals (Sweden)

    Sumire Ishida

    Full Text Available Lumen formation is important for morphogenesis; however, an unanswered question is whether it involves the collective migration of epithelial cells. Here, using a collagen gel overlay culture method, we show that Madin-Darby canine kidney cells migrated collectively and formed a luminal structure in a collagen gel. Immediately after the collagen gel overlay, an epithelial sheet folded from the periphery, migrated inwardly, and formed a luminal structure. The inhibition of integrin-β1 or Rac1 activity decreased the migration rate of the peripheral cells after the sheets folded. Moreover, lumen formation was perturbed by disruption of apical-basolateral polarity induced by transforming growth factor-β1. These results indicate that cell migration and cell polarity play an important role in folding. To further explore epithelial sheet folding, we developed a computer-simulated mechanical model based on the rigidity of the extracellular matrix. It indicated a soft substrate is required for the folding movement.

  4. Tooth root regeneration using dental follicle cell sheets in combination with a dentin matrix - based scaffold.

    Science.gov (United States)

    Yang, Bo; Chen, Gang; Li, Jie; Zou, Qing; Xie, Dan; Chen, Yali; Wang, Hang; Zheng, Xiaohui; Long, Jie; Tang, Wei; Guo, Weihua; Tian, Weidong

    2012-03-01

    Stem cell mediated tissue engineering has been acknowledged as a prospective strategy for repairing and replacing damaged and lost tissues. However, the low survival rate of implanted stem cells proves to be a major challenge in the management of transplantation failures. While previous studies have indicated the effectiveness of tissue engineered cell sheets in improving the survival rate of implanted cells, we have recently demonstrated the use of treated dentin matrix (TDM) as a biological scaffold and dental follicle cells (DFCs) as the seeding cells for dentinogenesis and tooth root construction. This study proposes a strategy utilizing TDM with human dental follicle cell sheets (DFCSs) for root regeneration. The biological characteristics and changes of human DFCSs under the effect of TDM were studied with scanning electron microscopy, transmission electron microscopy, immunofluorescence microscopy, immunohistochemistry and quantitative real-time PCR. DFCSs combined with TDM were implanted subcutaneously into the dorsum of mice. Histological examination of the harvested grafts revealed a whirlpool-like alignment of the DFCs in multiple layers that were positive for COLI, integrinβ1, fibronectin and alkaline phosphatase (ALP), suggestive of the formation of a rich extracellular matrix. DFCSs, under the effect of TDM, highly expressed DMP-1 and bone sialoprotein (BSP), indicating their potential for odontogenesis and osteogenesis. Importantly, in vivo, TDM could induce and support DFCSs to develop new dentin-pulp like tissues and cementum-periodontal complexes that were positive for markers such as DSP, nestin and VIII factors, COLI and cementum attachment protein (CAP), implying successful root regeneration. Therefore, DFCSs combined with TDM may prove to be a better strategy for the construction of tooth root, and is a prospective approach that could be utilized for the treatment of root or tooth defect or loss in future.

  5. Composite mandibular allografts in canines

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To evaluate the feasibility of transplanting composite mandibular allografts to repair large mandibular defects. Methods: Three composite mandibular transplantation models were established. The first model consisted of hemimandible with the attached teeth, muscle and skin, and oral mucosa. The second model was transplanted in the same way with the first one excluding oral mucosa and some teeth, and third one excluding the oral mucosa and all dental crowns. Fourteen transplanting operations were performed in canines. Cyclosporine A and methylprednisone were given for immunosuppression. Results: The composite mandibular organs had an effective and closed return circuit. Transplantation of vascularized allograft of mandibular compound organs was feasible. Two longest time survivors of 67 d and 76 d were in the third model group. Cyclosporine A was successful in suppressing rejection of transplanted composite allograft and prolonging survival time of transplantation models. Conclusions: The composite mandibular allografts were available with large block of living composite tissue,and helpful in restoration of appearance and function for severe mandibular defects.

  6. Emphysema in the renal allograft

    Energy Technology Data Exchange (ETDEWEB)

    Potter, J.L.; Sullivan, B.M.; Fluornoy, J.G.; Gerza, C.

    1985-04-01

    Two diabetic patients in whom emphysematous pyelonephritis developed after renal transplantation are described. Clinical recognition of this unusual and serious infection is masked by the effects of immunosuppression. Abdominal radiographic, ultrasound, and computed tomography findings are discussed. The clinical presentation includes urinary tract infection, sepsis, and acute tubular malfunction of the allograft in insulin-dependent diabetics.

  7. Cell sheets image validation of phase-diversity homodyne OCT and effect of the light irradiation on cells

    Science.gov (United States)

    Senda, Naoko; Osawa, Kentaro

    2016-04-01

    Optical coherence tomography (OCT) is one of powerful 3D tissue imaging tools with no fluorescence staining. We have reported that Phase-Diversity Homodyne OCT developed in Hitachi could be useful for non-invasive regeneration tissue evaluation test. The OCT enables cell imaging because of high resolution (axial resolution; ~2.6 μm, lateral resolution; ~1 μm, in the air), whereas conventional OCT was not used for cell imaging because of low resolution (10~20 μm). Furthermore, the OCT has advantage over other 3D imaging devices in cost because the light source and the objective were originally used as an optical pickup of compact disc. In this report, we aimed to assess effectiveness and safety of Phase-Diversity Homodyne OCT cell imaging. Effectiveness of OCT was evaluated by imaging a living cell sheet of human oral mucosal epithelial cells. OCT images were compared with reflection confocal microscopy (RCM) images, because confocal optical system is the highest resolution (<1 μm) 3D in vivo imaging technique. Similar nuclei images were confirmed with OCT and RCM, which suggested the OCT has enough resolution to image nuclei inside a cell sheet. Degree of differentiation could be estimated using OCT images, which becomes possible because the size of cells depends on distribution of differentiation. Effect of the OCT light irradiation on cells was studied using NIH/3T3 cells. Light irradiation, the exposure amount of which is equivalent to OCT, had no impact on cell shape, cell viability, and proliferation rate. It suggested that the light irradiation has no cell damage under the condition.

  8. Middle ear mucosal regeneration with three-dimensionally tissue-engineered autologous middle ear cell sheets in rabbit model.

    Science.gov (United States)

    Yaguchi, Yuichiro; Murakami, Daisuke; Yamato, Masayuki; Hama, Takanori; Yamamoto, Kazuhisa; Kojima, Hiromi; Moriyama, Hiroshi; Okano, Teruo

    2016-03-01

    The likelihood of recurrent retraction and adhesion of newly formed tympanic membrane is high when middle ear mucosa is extensively lost during cholesteatoma and adhesive otitis media surgery. If rapid postoperative regeneration of the mucosa on the exposed bone surface can be achieved, prevention of recurrent eardrum adhesion and cholesteatoma formation, for which there has been no definitive treatment, can be expected. Suture-less transplantation of tissue-engineered mucosal cell sheets was examined immediately after the operation of otitis media surgery in order to quickly regenerate middle ear mucosa lost during surgery in a rabbit model. Transplantable middle ear mucosal cell sheets with a three-dimensional tissue architecture very similar to native middle ear mucosa were fabricated from middle ear mucosal tissue fragments obtained in an autologous manner from middle ear bulla on temperature-responsive culture surfaces. Immediately after the mucosa was resected from middle ear bone bulla inner cavity, mucosal cell sheets were grafted at the resected site. Both bone hyperplasia and granulation tissue formation were inhibited and early mucosal regeneration was observed in the cell sheet-grafted group, compared with the control group in which only mucosal removal was carried out and the bone surface exposed. This result indicates that tissue engineered mucosal cell sheets would be useful to minimize complications after the surgical operation on otitis media and future clinical application is expected.

  9. Effect of Sheet Resistance and Morphology of ITO Thin Films on Polymer Solar Cell Characteristics

    Directory of Open Access Journals (Sweden)

    Ram Narayan Chauhan

    2012-01-01

    Full Text Available Solar cell fabrication on flexible thin plastic sheets needs deposition of transparent conducting anode layers at low temperatures. ITO thin films are deposited on glass by RF sputtering at substrate temperature of 70∘C and compare their phase, morphology, optical, and electrical properties with commercial ITO. The films contain smaller nanocrystallites in (222 preferred orientation and exhibit comparable optical transmittance (~95% in the wavelength range of 550–650 nm, but high sheet resistance of ~103 Ω/□ (the value being ~36 Ω/□ for commercial ITO.The polymer solar cells with PEDOT: PSS and P3HT: PCBM layers realized on RF sputtered vis-a-vis commercial ITO thin films are shown to display a marginal difference in power conversion efficiency, low fill factor, and low open-circuit voltage but increased short-circuit current density. The decrease in fill factor, open-circuit voltage is compensated by increased short-circuit current. Detailed study is made of increased short-circuit current density.

  10. Periodontal regeneration in swine after cell injection and cell sheet transplantation of human dental pulp stem cells following good manufacturing practice

    OpenAIRE

    2016-01-01

    Background Periodontitis, one of the most prevalent infectious diseases in humans, results in the destruction of tooth-supporting tissues. The purpose of the present study is to evaluate the effect of cell injection and cell sheet transplantation on periodontal regeneration in a swine model. Methods In the present study, human dental pulp stem cells (hDPSCs) were transplanted into a swine model for periodontal regeneration. Twelve miniature pigs were used to generate periodontitis with bone d...

  11. Mechanism of arterial remodeling in chronic allograft vasculopathy

    Institute of Scientific and Technical Information of China (English)

    Qichang Zheng; Shanglong Liu; Zifang Song

    2011-01-01

    Chronic allograft vasculopathy (CAV) remains a major obstacle for long-term survival of grafts even though therapeutic strategies have improved considerably in recent years.CAV is characterized by concentric and diffuse neointimal formation,medial apoptosis,infiltration of lymphocyte or inflammatory cells,and deposition of extracellular matrix both in arteries and veins.Recent studies have shown that stem cells derived from the recipient contribute to neointimal formation under the regulation of chemokines and cytokines.Arterial remodeling in allografts eventually causes ischemic graft failure.The pathogenesis is multi-factorial with both immunologic and non-immunological factors being involved.The immunological factors have been discussed extensively in other articles.This review focuses mainly on the arterial remodeling that occurs in 3 layers of vessel walls including intimal injury,accumulation of smooth muscle-like cells in the neointimal,medial smooth muscle cell apoptosis,adventitial fibrosis,and deposition of extracellular matrix.

  12. A novel cell-sheet technology that achieves durable factor VIII delivery in a mouse model of hemophilia A.

    Science.gov (United States)

    Tatsumi, Kohei; Sugimoto, Mitsuhiko; Lillicrap, David; Shima, Midori; Ohashi, Kazuo; Okano, Teruo; Matsui, Hideto

    2013-01-01

    Gene- or cell-based therapies aimed at creating delivery systems for coagulation factor VIII (FVIII) protein have emerged as promising options for hemophilia A treatment. However, several issues remain to be addressed regarding the efficacies and adverse events of these new classes of therapies. To improve an existing cell-based therapy involving the subcutaneous transplantation of FVIII-transduced blood outgrowth endothelial cells (BOECs), we employed a novel cell-sheet technology that allows individual dispersed cells to form a thin and contiguous monolayer without traditional bioabsorbable scaffold matrices. Compared to the traditional methodology, our cell-sheet approach resulted in longer-term and 3-5-fold higher expression of FVIII (up to 11% of normal) in recipient hemophilia A mice that lacked a FVIII humoral immune response due to transient immunosuppression with cyclophosphamide. Histological studies revealed that the transplanted BOEC sheets were structured as flat clusters, supporting the long-term expression of therapeutic FVIII in plasma from an ectopic subcutaneous space. Our novel tissue-engineering approach using genetically modified BOEC sheets could aid in development of cell-based therapy that will allow safe and effective in vivo delivery of functional FVIII protein in patients with hemophilia A.

  13. A novel cell-sheet technology that achieves durable factor VIII delivery in a mouse model of hemophilia A.

    Directory of Open Access Journals (Sweden)

    Kohei Tatsumi

    Full Text Available Gene- or cell-based therapies aimed at creating delivery systems for coagulation factor VIII (FVIII protein have emerged as promising options for hemophilia A treatment. However, several issues remain to be addressed regarding the efficacies and adverse events of these new classes of therapies. To improve an existing cell-based therapy involving the subcutaneous transplantation of FVIII-transduced blood outgrowth endothelial cells (BOECs, we employed a novel cell-sheet technology that allows individual dispersed cells to form a thin and contiguous monolayer without traditional bioabsorbable scaffold matrices. Compared to the traditional methodology, our cell-sheet approach resulted in longer-term and 3-5-fold higher expression of FVIII (up to 11% of normal in recipient hemophilia A mice that lacked a FVIII humoral immune response due to transient immunosuppression with cyclophosphamide. Histological studies revealed that the transplanted BOEC sheets were structured as flat clusters, supporting the long-term expression of therapeutic FVIII in plasma from an ectopic subcutaneous space. Our novel tissue-engineering approach using genetically modified BOEC sheets could aid in development of cell-based therapy that will allow safe and effective in vivo delivery of functional FVIII protein in patients with hemophilia A.

  14. Anterior cruciate ligament reconstruction with allograft tendons.

    Science.gov (United States)

    Strickland, Sabrina M; MacGillivray, John D; Warren, Russell F

    2003-01-01

    Allograft tissue allows reconstruction of the ACL without the donor site morbidity that can be caused by autograft harvesting. Patients who must kneel as a part of their occupation or chosen sport are particularly good candidates for allograft reconstruction. Patients over 45 years of age and those requiring revision ACL surgery can also benefit from the use and availability of allograft tendons. In some cases, patients or surgeons may opt for allograft tendons to maximize the result or morbidity ratio. Despite advances in cadaver screening and graft preparation, there remain risks of disease transmission and joint infection after allograft implantation. Detailed explanation and informed consent is vitally important in cases in which allograft tissue is used.

  15. Allograft pretreatment for the repair of sciatic nerve defects:green tea polyphenolsversus radiation

    Institute of Scientific and Technical Information of China (English)

    Sheng-hu Zhou; Ping Zhen; Shen-song Li; Xiao-yan Liang; Ming-xuan Gao; Qi Tian; Xu-sheng Li

    2015-01-01

    Pretreatment of nerve allografts by exposure to irradiation or green tea polyphenols can elimi-nate neuroimmunogenicity, inhibit early immunological rejection, encourage nerve regeneration and functional recovery, improve tissue preservation, and minimize postoperative infection. In the present study, we investigate which intervention achieves better results. We produced a 1.0 cm sciatic nerve defect in rats, and divided the rats into four treatment groups: autograft, fresh nerve allograft, green tea polyphenol-pretreated (1 mg/mL, 4°C) nerve allograft, and irradiation-pre-treated nerve allograft (26.39 Gy/min for 12 hours; total 19 kGy). The animals were observed, and sciatic nerve electrophysiology, histology, and transmission electron microscopy were carried out at 6 and 12 weeks after grafting. The circumference and structure of the transplanted nerve in rats that received autografts or green tea polyphenol-pretreated nerve allografts were similar to those of the host sciatic nerve. Compared with the groups that received fresh or irradiation-pre-treated nerve allografts, motor nerve conduction velocity in the autograft and fresh nerve allograft groups was greater, more neurites grew into the allografts, Schwann cell proliferation was evident, and a large number of new blood vessels was observed; in addition, massive myelinated nerve ifbers formed, and abundant microiflaments and microtubules were present in the axoplasm. Our ifndings indicate that nerve allografts pretreated by green tea polyphenols are equivalent to trans-planting autologous nerves in the repair of sciatic nerve defects, and promote nerve regeneration. Pretreatment using green tea polyphenols is better than pretreatment with irradiation.

  16. Effect of the compact Ti layer on the efficiency of dye-sensitized solar cells assembled using stainless steel sheets

    Science.gov (United States)

    Meng, Lijian; Wu, Mingxing; Wang, Yongmei; Guo, Wei; Ma, Chunyu; Ma, Tingli; Silva, Rui

    2013-06-01

    Titanium films have been deposited on stainless steel metal sheets using dc magnetron sputtering technique at different substrate temperatures. The structure of the titanium films strongly depend on the substrate temperature. The titanium film deposited at the substrate temperature lower than 300 °C has a loose flat sheet grains structure and the titanium film prepared at the substrate temperature higher than 500 °C has a dense nubby grains structure. The DSSC assembled using stainless steel sheet coated with titanium film deposited at high substrate temperature has a low charge transfer resistance in the TiO2/Ti interface and results in a high conversion efficiency. The DSSC assembled using stainless steel sheet coated with titanium film deposited at temperature higher than 500 °C has higher conversion efficiency than that assembled using titanium metal sheet as the substrate. The maximum conversion efficiency, 2.26% is obtained for DSSC assembled using stainless steel sheet coated with titanium film deposited at 700 °C substrate temperature, which is about 70% of the conversion efficiency of the FTO reference cell used in this study.

  17. Mucormycosis (zygomycosis) of renal allograft.

    Science.gov (United States)

    Gupta, Krishan L; Joshi, Kusum; Kohli, Harbir S; Jha, Vivekanand; Sakhuja, Vinay

    2012-12-01

    Fungal infection is relatively common among renal transplant recipients from developing countries. Mucormycosis, also known as zygomycosis, is one of the most serious fungal infections in these patients. The most common of presentation is rhino-cerebral. Isolated involvement of a renal allograft is very rare. A thorough search of literature and our medical records yielded a total of 24 cases with mucormycosis of the transplanted kidney. There was an association with cytomegalovirus (CMV) infection and anti-rejection treatment in these patients and most of these transplants were performed in the developing countries from unrelated donors. The outcome was very poor with an early mortality in 13 (54.5%) patients. Renal allograft mucormycosis is a relatively rare and potentially fatal complication following renal transplantation. Early diagnosis, graft nephrectomy and appropriate antifungal therapy may result in an improved prognosis for these patients.

  18. Leiomyoma in a Renal Allograft

    Directory of Open Access Journals (Sweden)

    Yan Jun Li

    2016-01-01

    Full Text Available Leiomyomas are smooth muscle tumours that are rarely found in the kidney. There is one report of a leiomyoma in a kidney transplant in a paediatric recipient. Here, we report an adult renal transplant recipient who developed an Epstein-Barr virus-positive leiomyoma in his allograft 15 years after transplantation. The patient was converted to everolimus for posttransplant immunosuppression management and there was no sign of progression over a year.

  19. Quantitative neuroanatomy of all Purkinje cells with light sheet microscopy and high-throughput image analysis

    Directory of Open Access Journals (Sweden)

    Ludovico eSilvestri

    2015-05-01

    Full Text Available Characterizing the cytoarchitecture of mammalian central nervous system on a brain-wide scale is becoming a compelling need in neuroscience. For example, realistic modeling of brain activity requires the definition of quantitative features of large neuronal populations in the whole brain. Quantitative anatomical maps will also be crucial to classify the cytoarchtitectonic abnormalities associated with neuronal pathologies in a high reproducible and reliable manner. In this paper, we apply recent advances in optical microscopy and image analysis to characterize the spatial distribution of Purkinje cells across the whole cerebellum. Light sheet microscopy was used to image with micron-scale resolution a fixed and cleared cerebellum of an L7-GFP transgenic mouse, in which all Purkinje cells are fluorescently labeled. A fast and scalable algorithm for fully automated cell identification was applied on the image to extract the position of all the fluorescent Purkinje cells. This vectorized representation of the cell population allows a thorough characterization of the complex three-dimensional distribution of the neurons, highlighting the presence of gaps inside the lamellar organization of Purkinje cells, whose density is believed to play a significant role in autism spectrum disorders. Furthermore, clustering analysis of the localized somata permits dividing the whole cerebellum in groups of Purkinje cells with high spatial correlation, suggesting new possibilities of anatomical partition. The quantitative approach presented here can be extended to study the distribution of different types of cell in many brain regions and across the whole encephalon, providing a robust base for building realistic computational models of the brain, and for unbiased morphological tissue screening in presence of pathologies and/or drug treatments.

  20. Low cost monocrystalline silicon sheet fabrication for solar cells by advanced ingot technology

    Science.gov (United States)

    Fiegl, G. F.; Bonora, A. C.

    1980-01-01

    The continuous liquid feed (CLF) Czochralski furnace and the enhanced I.D. slicing technology for the low-cost production of monocrystalline silicon sheets for solar cells are discussed. The incorporation of the CLF system is shown to improve ingot production rate significantly. As demonstrated in actual runs, higher than average solidification rates (75 to 100 mm/hr for 150 mm 1-0-0 crystals) can be achieved, when the system approaches steady-state conditions. The design characteristics of the CLF furnace are detailed, noting that it is capable of precise control of dopant impurity incorporation in the axial direction of the crystal. The crystal add-on cost is computed to be $11.88/sq m, considering a projected 1986 25-slice per cm conversion factor with an 86% crystal growth yield.

  1. Tissue engineered allograft total disc transplantation using exogenous nucleus pulposus cells: an experimental study in a beagle model%犬同种异体椎间盘复合髓核细胞移植初探

    Institute of Scientific and Technical Information of China (English)

    辛洪奎; 张超; 王德利; 吴剑宏; 王超峰; 何勍; 阮狄克

    2012-01-01

    功能的潜力,有望保证同种异体椎间盘移植的远期疗效.%Objectives: To investigate in vivo rehepitation of the transplanted tissue engineered allograft total disc and to explore the biological effect of nucleus pulposus(NP) cells or hTERT gene transfected NP cells on allograft total disc transplantation. Methods: Eighteen canine lumbar intervertebral discs were obtained from 5 canines and cryopreserved in liquid nitrogen. Canine nucleus pulposus cells were isolated and transduced with rAAV-hTERT. The cells were injected into the discs to construct a "tissue-engineered" allograft disc(group A). NP cells and DMEM/F12 were used for positive control(group B) and blank control(group C) respectively. 18 beagle dogs received the 3 groups of allograft IVD composites implantation respectively. Radiographic examination was performed at 4, 8 and 12 weeks after implantation. At 12 weeks after operation, all dogs were sacrificed and the lumbar spines were harvested for the biomechanical test and histological analysis, ectogenic NP cell tracing and hTERT mRNA analysis. Results: Bony fusion between intervertebral disc allograft and adjacent host intervertebral body was observed in all animals. The disc height and T2 signal intensity preservation'in "group A and B were better than group C. MRI showed typical degenerative changes in group C. In group A, the normalized grayscale of the transplanted disc in MRI image was significant higher than that of the controls at 12 weeks. Biomechanical test showed a poor stability preservation in group C compared with group A and B. PKH-26 positive cells were identified within the allograft discs in group A at 12 weeks, which provided matrix for cell survival. Histological analysis showed the NP cell morphology, cell number and distribution of the allograft discs were better preserved in group A and B than group C at 12 weeks of follow -up. Conclusions: NP cells or hTERT loaded NP cells intervention can effectively resist the

  2. A TLR9 agonist promotes IL-22-dependent pancreatic islet allograft survival in type 1 diabetic mice

    Science.gov (United States)

    Tripathi, Deepak; Venkatasubramanian, Sambasivan; Cheekatla, Satyanarayana S.; Paidipally, Padmaja; Welch, Elwyn; Tvinnereim, Amy R.; Vankayalapati, Ramakrishna

    2016-01-01

    Pancreatic islet transplantation is a promising potential cure for type 1 diabetes (T1D). Islet allografts can survive long term in the liver parenchyma. Here we show that liver NK1.1+ cells induce allograft tolerance in a T1D mouse model. The tolerogenic effects of NK1.1+ cells are mediated through IL-22 production, which enhances allograft survival and increases insulin secretion. Increased expression of NKG2A by liver NK1.1+ cells in islet allograft-transplanted mice is involved in the production of IL-22 and in the reduced inflammatory response to allografts. Vaccination of T1D mice with a CpG oligonucleotide TLR9 agonist (ODN 1585) enhances expansion of IL-22-producing CD3-NK1.1+ cells in the liver and prolongs allograft survival. Our study identifies a role for liver NK1.1+ cells, IL-22 and CpG oligonucleotides in the induction of tolerance to islet allografts in the liver parenchyma. PMID:27982034

  3. The impact of donor-specific anti-HLA antibodies on late kidney allograft failure.

    Science.gov (United States)

    Loupy, Alexandre; Hill, Gary S; Jordan, Stanley C

    2012-04-17

    Despite improvements in outcomes of renal transplantation, kidney allograft loss remains substantial, and is associated with increased morbidity, mortality and costs. Identifying the pathologic pathways responsible for allograft loss, and the attendant development of therapeutic interventions, will be one of the guiding future objectives of transplant medicine. One of the most important advances of the past decade has been the demonstration of the destructive power of anti-HLA alloantibodies and their association with antibody-mediated rejection (ABMR). Compelling evidence exists to show that donor-specific anti-HLA antibodies (DSAs) are largely responsible for the chronic deterioration of allografts, a condition previously attributed to calcineurin inhibitor toxicity and chronic allograft nephropathy. The emergence of sensitive techniques to detect DSAs, together with advances in the assessment of graft pathology, have expanded the spectrum of what constitutes ABMR. Today, subtler forms of rejection--such as indolent ABMR, C4d-negative ABMR, and transplant arteriopathy--are seen in which DSAs exert a marked pathological effect. In addition, arteriosclerosis, previously thought to be a bystander lesion related to the vicissitudes of aging, is accelerated in ABMR. Advances in our understanding of the pathological significance of DSAs and ABMR show their primacy in the mediation of chronic allograft destruction. Therapies aimed at B cells, plasma cells and antibodies will be important therapeutic options to improve the length and quality of kidney allograft survival.

  4. Demand for human allograft tissue in Canada.

    Science.gov (United States)

    Lakey, Jonathan R T; Mirbolooki, Mohammadreza; Rogers, Christina; Mohr, Jim

    2007-01-01

    There is relatively little known about the demand for allograft tissues in Canada. The Canadian Council for Donation and Transplantation (CCDT) is a national advisory body that undertook a comprehensive "market survey" to estimate surgical demand for human allograft tissues in Canada. The report "Demand for Human Allograft Tissue in Canada" reflects survey results sent to 5 prominent User Groups. User Groups were identified as orthopaedic surgeons; neurosurgeons; corneal transplant surgeons; plastic surgeons, specifically those at Canadian Burn Units; and cardiac surgeons (adult and paediatric surgery). The demand for allograft grafts was determined and then extrapolated across the total User Group and then increases in allograft tissue use over the next 1-2 years across User Groups were predicted. The overall response rate for the survey was 21.4%. It varied from a low of 19.6% for the orthopaedic survey to a high of 40.5% for the corneal survey. The estimated current demand for allograft tissue in Canada ranges from a low of 34,442 grafts per year to a high of 62,098 grafts per year. The predicted increase in use of allograft tissue over the next 1-2 year period would suggest that annual demand could rise to somewhere in the range of 42,589-72,210 grafts. The highest rated preferences (98% and 94%) were for accredited and Canadian tissue banks, respectively. This study represents a key step in addressing the paucity of information concerning the demand for allograft tissue in Canada.

  5. Allograft tolerance induced by donor apoptotic lymphocytes requires phagocytosis in the recipient

    Science.gov (United States)

    Sun, E.; Gao, Y.; Chen, J.; Roberts, A. I.; Wang, X.; Chen, Z.; Shi, Y.

    2004-01-01

    Cell death through apoptosis plays a critical role in regulating cellular homeostasis. Whether the disposal of apoptotic cells through phagocytosis can actively induce immune tolerance in vivo, however, remains controversial. Here, we report in a rat model that without using immunosuppressants, transfusion of apoptotic splenocytes from the donor strain prior to transplant dramatically prolonged survival of heart allografts. Histological analysis verified that rejection signs were significantly ameliorated. Splenocytes from rats transfused with donor apoptotic cells showed a dramatically decreased response to donor lymphocyte stimulation. Most importantly, blockade of phagocytosis in vivo, either with gadolinium chloride to disrupt phagocyte function or with annexin V to block binding of exposed phosphotidylserine to its receptor on phagocytes, abolished the beneficial effect of transfused apoptotic cells on heart allograft survival. Our results demonstrate that donor apoptotic cells promote specific allograft acceptance and that phagocytosis of apoptotic cells in vivo plays a crucial role in maintaining immune tolerance.

  6. Inflammatory mediators and cytotoxins in cardiac allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, R.P.; Powell, W.S.; Blais, D.; Marghesco, D.

    1986-03-01

    Though organ allograft rejection in rats has been linked to delayed type hypersensitivity (DTH) the pathogenesis of DTH induced tissue injury is uncertain. Accordingly, the authors have undertaken to identify the following inflammatory mediators/cytotoxins in rejecting rat cardiac allografts (WF ..-->.. LEW, day 5): phospholipase A/sub 2/(PLA/sub 2/ in cardiac homogenates assessed using /sup 14/C oleate labelled E Coli), PAF in lipid extracts of grafts measured by aggregation of rabbit platelets, arachidonic acid (AA) metabolites (HPLC analysis of products released from isolated perfused hearts and slices prelabelled with /sup 3/H-AA), lymphotoxin and/or tumor necrosis factor (LT/TNF release in vitro from infiltrating mononuclear cells assayed using cell line varies as L929. Briefly, aliquots of homogenates (10ml) of rejecting grafts demonstrated PLA/sub 2/ activity as evidenced by liberation of FFA from bacterial phospholipids (baseline 3%, 1 ..mu..1 4%, 25 ..mu..l 24%, 100 /sup +/l 29%, 200 ..mu..l 39%; control hearts, 200 ..mu..l 5%). Rejecting cardiac allografts contained approximately 10 ng PAF while PAF recovered from syngeneic grafts was less than or equal to 5 ng. Observed changes in eicosanoid biosynthesis with rejection were limited to a decrement in 6 oxo PGF/sub /sub 1/..cap alpha../ release. Infiltrating mononuclear cells recovered from rejecting grafts released greater than or equal to 64 units of cytotoxin (LT and/or TNF). The author present results, documenting a decrement in prostacyclin release by rejecting heart grafts, the presence of PLA/sub 2/ and PAF and the release of cytotoxins (LT and/or TNF) by infiltrating mononuclear cells are compatible with the thesis that allograft rejection must be viewed as a complex immune/inflammatory process. Additional studies are clearly required to define roles of these and other soluble factors in homograft destruction.

  7. Acellular nerve allograft promotes selective regeneration

    Institute of Scientific and Technical Information of China (English)

    Haili Xin; Guanjun Wang; Xinrong He; Jiang Peng; Quanyi Guo; Wenjing Xu

    2011-01-01

    Acellular nerve allograft preserves the basilar membrane tube and extracellular matrix, which pro-motes selective regeneration of neural defects via bridging. In the present study, a Sprague Dawley rat sciatic nerve was utilized to prepare acellular nerve allografts through the use of the chemical extraction method. Subsequently, the allograft was transplanted into a 10-mm sciatic nerve defect in Wistar rats, while autologous nerve grafts from Wistar rats served as controls. Compared with autologous nerve grafts, the acellular nerve allografts induced a greater number of degenerated nerve fibers from sural nerves, as well as a reduced misconnect rate in motor fibers, fewer acetyl-choline esterase-positive sural nerves, and a greater number of carbonic anhydrase-positive senso-ry nerve fibers. Results demonstrated that the acellular nerve allograft exhibited significant neural selective regeneration in the process of bridging nerve defects.

  8. Simple suspension culture system of human iPS cells maintaining their pluripotency for cardiac cell sheet engineering.

    Science.gov (United States)

    Haraguchi, Yuji; Matsuura, Katsuhisa; Shimizu, Tatsuya; Yamato, Masayuki; Okano, Teruo

    2015-12-01

    In this study, a simple three-dimensional (3D) suspension culture method for the expansion and cardiac differentiation of human induced pluripotent stem cells (hiPSCs) is reported. The culture methods were easily adapted from two-dimensional (2D) to 3D culture without any additional manipulations. When hiPSCs were directly applied to 3D culture from 2D in a single-cell suspension, only a few aggregated cells were observed. However, after 3 days, culture of the small hiPSC aggregates in a spinner flask at the optimal agitation rate created aggregates which were capable of cell passages from the single-cell suspension. Cell numbers increased to approximately 10-fold after 12 days of culture. The undifferentiated state of expanded hiPSCs was confirmed by flow cytometry, immunocytochemistry and quantitative RT-PCR, and the hiPSCs differentiated into three germ layers. When the hiPSCs were subsequently cultured in a flask using cardiac differentiation medium, expression of cardiac cell-specific genes and beating cardiomyocytes were observed. Furthermore, the culture of hiPSCs on Matrigel-coated dishes with serum-free medium containing activin A, BMP4 and FGF-2 enabled it to generate robust spontaneous beating cardiomyocytes and these cells expressed several cardiac cell-related genes, including HCN4, MLC-2a and MLC-2v. This suggests that the expanded hiPSCs might maintain the potential to differentiate into several types of cardiomyocytes, including pacemakers. Moreover, when cardiac cell sheets were fabricated using differentiated cardiomyocytes, they beat spontaneously and synchronously, indicating electrically communicative tissue. This simple culture system might enable the generation of sufficient amounts of beating cardiomyocytes for use in cardiac regenerative medicine and tissue engineering.

  9. The Spectrum of Renal Allograft Failure

    Science.gov (United States)

    Chand, Sourabh; Atkinson, David; Collins, Clare; Briggs, David; Ball, Simon; Sharif, Adnan; Skordilis, Kassiani; Vydianath, Bindu; Neil, Desley; Borrows, Richard

    2016-01-01

    Background Causes of “true” late kidney allograft failure remain unclear as study selection bias and limited follow-up risk incomplete representation of the spectrum. Methods We evaluated all unselected graft failures from 2008–2014 (n = 171; 0–36 years post-transplantation) by contemporary classification of indication biopsies “proximate” to failure, DSA assessment, clinical and biochemical data. Results The spectrum of graft failure changed markedly depending on the timing of allograft failure. Failures within the first year were most commonly attributed to technical failure, acute rejection (with T-cell mediated rejection [TCMR] dominating antibody-mediated rejection [ABMR]). Failures beyond a year were increasingly dominated by ABMR and ‘interstitial fibrosis with tubular atrophy’ without rejection, infection or recurrent disease (“IFTA”). Cases of IFTA associated with inflammation in non-scarred areas (compared with no inflammation or inflammation solely within scarred regions) were more commonly associated with episodes of prior rejection, late rejection and nonadherence, pointing to an alloimmune aetiology. Nonadherence and late rejection were common in ABMR and TCMR, particularly Acute Active ABMR. Acute Active ABMR and nonadherence were associated with younger age, faster functional decline, and less hyalinosis on biopsy. Chronic and Chronic Active ABMR were more commonly associated with Class II DSA. C1q-binding DSA, detected in 33% of ABMR episodes, were associated with shorter time to graft failure. Most non-biopsied patients were DSA-negative (16/21; 76.1%). Finally, twelve losses to recurrent disease were seen (16%). Conclusion This data from an unselected population identifies IFTA alongside ABMR as a very important cause of true late graft failure, with nonadherence-associated TCMR as a phenomenon in some patients. It highlights clinical and immunological characteristics of ABMR subgroups, and should inform clinical practice and

  10. Late Failing Heart Allografts: Pathology of Cardiac Allograft Vasculopathy and Association With Antibody-Mediated Rejection.

    Science.gov (United States)

    Loupy, A; Toquet, C; Rouvier, P; Beuscart, T; Bories, M C; Varnous, S; Guillemain, R; Pattier, S; Suberbielle, C; Leprince, P; Lefaucheur, C; Jouven, X; Bruneval, P; Duong Van Huyen, J P

    2016-01-01

    In heart transplantation, there is a lack of robust evidence of the specific causes of late allograft failure. We hypothesized that a substantial fraction of failing heart allografts may be associated with antibody-mediated injury and immune-mediated coronary arteriosclerosis. We included all patients undergoing a retransplantation for late terminal heart allograft failure in three referral centers. We performed an integrative strategy of heart allograft phenotyping by assessing the heart vascular tree including histopathology and immunohistochemistry together with circulating donor-specific antibodies. The main analysis included 40 explanted heart allografts patients and 402 endomyocardial biopsies performed before allograft loss. Overall, antibody-mediated rejection was observed in 19 (47.5%) failing heart allografts including 16 patients (40%) in whom unrecognized previous episodes of subclinical antibody-mediated rejection occurred 4.5 ± 3.5 years before allograft loss. Explanted allografts with evidence of antibody-mediated rejection demonstrated higher endothelitis and microvascular inflammation scores (0.89 ± 0.26 and 2.25 ± 0.28, respectively) compared with explanted allografts without antibody-mediated rejection (0.42 ± 0.11 and 0.36 ± 0.09, p = 0.046 and p < 0.0001, respectively). Antibody-mediated injury was observed in 62.1% of failing allografts with pure coronary arteriosclerosis and mixed (arteriosclerosis and atherosclerosis) pattern, while it was not observed in patients with pure coronary atherosclerosis (p = 0.0076). We demonstrate that antibody-mediated rejection is operating in a substantial fraction of failing heart allografts and is associated with severe coronary arteriosclerosis. Unrecognized subclinical antibody-mediated rejection episodes may be observed years before allograft failure.

  11. The effect of pregnancy on paternal skin allograft survival

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Elucidation of maternal-fetal tolerance mechanisms clarifies the role of regulatory T cells (Treg) in transplant tolerance. This study aim to investigate the effect of pregnancy on paternal skin allograft survival. Flow cytometry techniques, mixed lymphocytes reaction (MLR), PCR, real-time PCR and skin transplantation were key methods. Treg increased significantly from 4.2% before pregnancy to peak at 6.8% day 8 after pregnancy. Both heme oxygenase-1 (HO-1) and indoleamine 2,3-dioxygenase (IDO) mRNA express high in placenta while low in spleen (P<0.05). Although Treg increased during pregnancy, and splenocytes from the pregnant mice showed lower MLR response toward the paternal stimulator, single time pregnancy showed no significant protective effect on paternal skin allograft survival in the tested condition.

  12. The effect of pregnancy on paternal skin allograft survival

    Institute of Scientific and Technical Information of China (English)

    SHOU ZhangFei; XU YiFang; XIAO HuaYing; ZHOU Qin; CAI JieRu; YANG Yi; JIANG Hong; ZHANG WenJie; CHEN JiangHua

    2009-01-01

    Elucidation of maternal-fetal tolerance mechanisms clarifies the role of regulatory T cells (Treg)in transplant tolerance.This study aim to investigate the effect of pregnancy on paternal skin allograft survival.Flow cytometry techniques,mixed lymphocytes reaction (MLR),PCR,real-time PCR and skin transplantation were key methods.Treg increased significantly from 4.2% before pregnancy to peak at 6.8% day 8 after pregnancy.Both heme oxygenase-1 (HO-1)and indoleamine 2,3-dioxygenase (IDO)mRNA express high in placenta while low in spleen (P<0.05).Although Treg increased during pregnancy,and splenocytes from the pregnant mice showed lower MLR response toward the paternal stimulator,single time pregnancy showed no significant protective effect on paternal skin allograft survival in the tested condition.

  13. Inhibition of chemokine-glycosaminoglycan interactions in donor tissue reduces mouse allograft vasculopathy and transplant rejection.

    Directory of Open Access Journals (Sweden)

    Erbin Dai

    Full Text Available BACKGROUND: Binding of chemokines to glycosaminoglycans (GAGs is classically described as initiating inflammatory cell migration and creating tissue chemokine gradients that direct local leukocyte chemotaxis into damaged or transplanted tissues. While chemokine-receptor binding has been extensively studied during allograft transplantation, effects of glycosaminoglycan (GAG interactions with chemokines on transplant longevity are less well known. Here we examine the impact of interrupting chemokine-GAG interactions and chemokine-receptor interactions, both locally and systemically, on vascular disease in allografts. METHODOLOGY/PRINCIPAL FINDINGS: Analysis of GAG or CC chemokine receptor 2 (CCR2 deficiency were coupled with the infusion of viral chemokine modulating proteins (CMPs in mouse aortic allograft transplants (n = 239 mice. Inflammatory cell invasion and neointimal hyperplasia were significantly reduced in N-deacetylase-N-sulfotransferase-1 (Ndst1(f/fTekCre(+ heparan sulfate (GAG-deficient (Ndst1(-/-, p<0.044 and CCR2-deficient (Ccr2(-/-, p<0.04 donor transplants. Donor tissue GAG or CCR2 deficiency markedly reduced inflammation and vasculopathy, whereas recipient deficiencies did not. Treatment with three CMPs was also investigated; Poxviral M-T1 blocks CC chemokine receptor binding, M-T7 blocks C, CC, and CXC GAG binding, and herpesviral M3 binds receptor and GAG binding for all classes. M-T7 reduced intimal hyperplasia in wild type (WT (Ccr2(+/+, p< or =0.003 and Ccr2(-/-, pallografts, but not in Ndst1(-/- aortic allografts (p = 0.933. M-T1 and M3 inhibited WT (Ccr2(+/+ and Ndst1(+/+, p< or =0.006 allograft vasculopathy, but did not block vasculopathy in Ccr2(-/- (p = 0.61. M-T7 treatment alone, even without immunosuppressive drugs, also significantly prolonged survival of renal allograft transplants (p< or =0.001. CONCLUSIONS/SIGNIFICANCE: Interruption of chemokine-GAG interactions, even in the absence of chemokine

  14. Osteogenesis of human adipose-derived stem cells on hydroxyapatite-mineralized poly(lactic acid) nanofiber sheets

    Energy Technology Data Exchange (ETDEWEB)

    Kung, Fu-Chen [Department of Health Developing and Health Marketing, Kainan University, Taiwan (China); Lin, Chi-Chang, E-mail: chichang31@thu.edu.tw [Department of Chemical and Materials Engineering, Tunghai University, Taiwan (China); Lai, Wen-Fu T., E-mail: Laitw@tmu.edu.tw [Graduate Institute of Clinical Medicine, Taipei Medical University, Taiwan (China)

    2014-12-01

    Electrospun fiber sheets with various orientations (random, partially aligned, and aligned) and smooth and roughened casted membranes were prepared. Hydroxyapatite (HA) crystals were in situ formed on these material surfaces via immersion in 10 × simulated body fluid solution. The size and morphology of the resulting fibers were examined using scanning electron microscopy. The average diameter of the fibers ranged from 225 ± 25 to 1050 ± 150 nm depending on the electrospinning parameters. Biological experiment results show that human adipose-derived stem cells exhibit different adhesion and osteogenic differentiation on the three types of fiber. The cell proliferation and osteogenic differentiation were best on the aligned fibers. Similar results were found for phosphorylated focal adhesion kinase expression. Electrospun poly(lactic acid) aligned fibers mineralized with HA crystals provide a good environment for cell growth and osteogenic differentiation and thus have great potential in the tissue engineering field. - Highlights: • hADSCs show higher adhesion and proliferation on HA-precipitate electrospun fiber sheets than those of the control membranes. • HA-mineralized fiber groups greatly improve cell growth and increase FAK and p-FAK expressions. • HA-precipitate electrospun fiber sheets present higher ALP and OC activity through the study periods. • Electrospun PLA fiber mineralized with HA provides a good environment for cell growth and osteogenic differentiation. • A simple immersion of electrospun fibers in 10 × SBF are a potential matrix for bone tissue engineering.

  15. Radiation sterilization of skin allograft

    Science.gov (United States)

    Kairiyama, E.; Horak, C.; Spinosa, M.; Pachado, J.; Schwint, O.

    2009-07-01

    In the treatment of burns or accidental loss of skin, cadaveric skin allografts provide an alternative to temporarily cover a wounded area. The skin bank facility is indispensable for burn care. The first human skin bank was established in Argentina in 1989; later, 3 more banks were established. A careful donor selection is carried out according to the national regulation in order to prevent transmissible diseases. As cadaveric human skin is naturally highly contaminated, a final sterilization is necessary to reach a sterility assurance level (SAL) of 10 -6. The sterilization dose for 106 batches of processed human skin was determined on the basis of the Code of Practice for the Radiation Sterilization of Tissue Allografts: Requirements for Validation and Routine Control (2004) and ISO 11137-2 (2006). They ranged from 17.6 to 33.4 kGy for bioburdens of >10-162.700 CFU/100 cm 2. The presence of Gram negative bacteria was checked for each produced batch. From the analysis of the experimental results, it was observed that the bioburden range was very wide and consequently the estimated sterilization doses too. If this is the case, the determination of a tissue-specific dose per production batch is necessary to achieve a specified requirement of SAL. Otherwise if the dose of 25 kGy is preselected, a standardized method for substantiation of this dose should be done to confirm the radiation sterilization process.

  16. Highly Efficient Fuel Cell Electrodes from Few-Layer Graphene Sheets and Electrochemically Deposited Palladium Nanoparticles

    CERN Document Server

    Höltig, Michael; Kipp, Tobias; Mews, Alf

    2016-01-01

    An extremely efficient ethanol fuel cell electrode is produced by combining the large surface area of vertically oriented and highly conductive few-layer graphene sheets with electrochemically deposited palladium nanoparticles. The electrodes show an extraordinary high catalyst activity of up to 7977 mA/(mg Pd) at low catalyst loadings of 0.64 $\\mu$g/cm$^2$ and a very high current density of up to 106 mA/cm$^2$ at high catalyst loadings of 83 $\\mu$g/cm$^2$. Moreover, the low onset potentials combined with a good poisoning resistance and long-term stability make these electrodes highly suitable for real applications. These features are achieved by using a newly developed electrochemical catalyst deposition process exploiting high voltages of up to 3.5 kV. This technique allows controlling the catalyst amount ranging from a homogeneous widespread distribution of small ($\\leq$ 10 nm) palladium nanoparticles to rather dense layers of particles, while every catalyst particle has electrical contact to the graphene ...

  17. THE RISK OF EARLY LIVER ALLOGRAFT DYSFUNCTION IS ASSOCIATED WITH THE TLR-4 GENE GENOTYPE IN THE RS913930 SEQUENCE AND IS IMPLEMENTED VIA HMGB1 NUCLEAR PROTEIN, KUPFFER CELLS AND IL-23 ACTIVATION

    Directory of Open Access Journals (Sweden)

    A. E. Shcherba

    2016-01-01

    .02. The HMGB1 staining in the donor’s liver bioptates was higher in the EAD patients, 21 (20; 29 cells/mm2 in comparison with the patients without EAD, 16 (12; 18 (Mann–Whitney test, p = 0.0036. Conclusion. The early allograft liver dysfunction is associated with the genetic predisposition caused by the TLR-4 gene polymorphism and is implemented via the HMGB1, Kupffer cells and IL-23 activation. 

  18. Allograft safety in anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Cohen, Steven B; Sekiya, Jon K

    2007-10-01

    Allograft tissue seems to provide an excellent option for reconstruction of the ACL in the primary and revision setting. Although in general the risks of using allograft tissue in ACL reconstruction are low, the consequences of complications associated with disease or infection transmission or of recurrent instability secondary to graft failure are large. Surgeons should provide patients with the information available regarding allograft risks and should have thorough knowledge of the source and preparation of the grafts by their tissue bank before implantation for ACL reconstruction.

  19. Integration of a calcined bovine bone and BMSC-sheet 3D scaffold and the promotion of bone regeneration in large defects.

    Science.gov (United States)

    Liu, Yihan; Ming, Leiguo; Luo, Hailang; Liu, Wenjia; Zhang, Yongjie; Liu, Hongchen; Jin, Yan

    2013-12-01

    Reconstruction of large area bone defect with mechanical integrity to the skeleton is important for patient's rehabilitation. However with the limitation of scaffold material and suitable seed cell sources, the best treating strategy remains to be identified though various tissue engineering methods were reported. In this study, we investigated the feasibility of applying calcined bovine bone (CBB) which was coated by allograft bone marrow mesenchymal stem cells (BMSC)-sheet as a 3D scaffold material in bone repairing tissue engineering. The new scaffold material was implanted into osteoporosis rat cranial bone defects and repairing critical size bone defects (8 mm diameter). Data showed that CBB-BMSC-sheet combination had a stronger potential in osteogenic differentiation and mineralized formation both in vitro and in vivo than CBB-BMSC combination. In in vitro study BMSC-sheet had a more feasible characteristic upon bone repairing including richer ECM, larger mineralized area and stronger ALP activity in addition with a significant higher mRNA expression of osteogenic maker such as BMP-2, b-FGF, Col 1a1, OSX and Runx-2 than the control group. In in vivo study 3D reconstruction of micro CT, HE staining and bone strength results showed that newly formed bone in CBB-BMSC-sheet group was significant higher than that in CBB-BMSC group at 4, 8 and 12 weeks after transplantation in the aspect of area and volume. What was more, results indicated that allograft BMSC-sheet had survivaled in the scaffold material and participated in the newly formed bone which had the same thickness with surrounding autologous bone tissues after transplantation. Results of our study demonstrated that CBB-BMSC-sheet combination was a promising strategy in healing of large area bone defect in osteoporosis.

  20. Renal allograft rejection: sonography and scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Singh, A.; Cohen, W.N.

    1980-07-01

    A total of 30 renal allograft patients who had sonographic B scanning and radionuclide studies of the transplant was studied as to whether: (1) the allograft rejection was associated with any consistent and reliable sonographic features and (2) the sonograms complemented the radionuclide studies. Focal areas of decreased parenchymal echogenicity were the most striking and consistent sonographic finding in chymal echogenicity were the most striking and consistens sonographic finding in allograft rejection. This was observed in most of the patients exhibiting moderate or severe rejection, but was frequently absent with mild rejection. Areas of decreased parenchymal echogenicity were not seen during episodes of acute tubular necrosis. Therefore, sonography showing zones of decreased parenchymal echogenicity was complementary to radionuclide studies in the diagnosis of allograft rejection versus acute tubular necrosis. Corticomedullary demarcation was difficult to interpret because of technical variables, and was inconsistently related to rejection in this series.

  1. Specific unresponsiveness to skin allografts in burns.

    Science.gov (United States)

    Clark, G T; Moon, D J; Cunningham, P R; Johnson, T D; Thomas, J M; Thomas, F T

    1989-05-01

    We have examined the potential to provide long-term or even permanent wound coverage in a mouse model of a 30% total body surface area burn using skin allografts. Treatment of the recipient mouse with rabbit anti-mouse thymocyte serum (ATS) followed by donor bone marrow infusion induces a state of specific unresponsiveness to the skin allograft without the need for chronic immunosuppression. Specifically, a B6AF1 mouse receives a burn on Day -2 relative to grafting, ATS on Day -1, and Day +2, a skin allograft from a C3H/He mouse on Day 0, and infusion of C3H/He donor bone marrow on Day +6. We studied three groups of burned mice: Group I, allograft control (n = 5); Group II, allograft plus ATS (n = 12); and Group III, allograft plus ATS and bone marrow infusion (n = 15). Mean graft survival was compared using a one-way analysis of variance and a Student-Newman-Keuls post hoc test. There was no statistical difference in animal mortality among any of the three groups, and there was no evidence of infectious morbidity. Mean skin allograft survival was as follows: Group I, 9 days; Group II, 29 days; and Group III, 66 days (P less than 0.05 vs Group I and II). Nine animals in Group III had intact hair bearing grafts at 90 days when the study was terminated. This study suggests the potential use of induced specific unresponsiveness to skin allografts for wound coverage in thermal injury without use of chronic immunosuppression. In our animal study this was accomplished without increased mortality or apparent infectious morbidity.

  2. Computational Biology: Modeling Chronic Renal Allograft Injury.

    Science.gov (United States)

    Stegall, Mark D; Borrows, Richard

    2015-01-01

    New approaches are needed to develop more effective interventions to prevent long-term rejection of organ allografts. Computational biology provides a powerful tool to assess the large amount of complex data that is generated in longitudinal studies in this area. This manuscript outlines how our two groups are using mathematical modeling to analyze predictors of graft loss using both clinical and experimental data and how we plan to expand this approach to investigate specific mechanisms of chronic renal allograft injury.

  3. Type I and II Diabetic Adipose-Derived Stem Cells Respond In Vitro to Dehydrated Human Amnion/Chorion Membrane Allograft Treatment by Increasing Proliferation, Migration, and Altering Cytokine Secretion.

    Science.gov (United States)

    Massee, Michelle; Chinn, Kathryn; Lim, Jeremy J; Godwin, Lisa; Young, Conan S; Koob, Thomas J

    2016-02-01

    Objective: Human amniotic membranes have been shown to be effective for healing diabetic foot ulcers clinically and to regulate stem cell activity in vitro and in vivo; however, diabetic stem cells may be impaired as a sequela of the disease. In this study, dehydrated human amnion/chorion membrane (dHACM) allografts (EpiFix(®); MiMedx Group) were evaluated for their ability to regulate diabetic stem cells in vitro. Approach: Human adipose-derived stem cells (ADSCs) from normal, type I diabetic, and type II diabetic donors were treated with soluble extracts of dHACM and evaluated for proliferation after 3 days by DNA assay, chemotactic migration after 1 day by transwell assay, cytokine secretion after 3 days by multiplex ELISA, and gene expression after 5 days by reverse transcription-polymerase chain reaction. Results: Although diabetic ADSCs demonstrated decreased responses compared to normal ADSCs, dHACM treatment stimulated diabetic ADSCs to proliferate after 3 days and enhanced migration over 24 h, similar to normal ADSCs. dHACM-treated diabetic ADSCs modulated secretion of soluble signals, including regulators of inflammation, angiogenesis, and healing. All ADSCs evaluated also responded to dHACM treatment with altered expression of immunomodulatory genes, including interleukins (IL)-1α, IL-1β, and IL-1RA. Innovation: This is the first reported case demonstrating that diabetic ADSCs respond to novel amniotic membrane therapies, specifically treatment with dHACM. Conclusion: dHACM stimulated diabetic ADSCs to migrate, proliferate, and alter cytokine expression suggesting that, despite their diabetic origin, ADSCs may respond to dHACM to accelerate diabetic wound healing.

  4. Polyoma (BK) virus associated urothelial carcinoma originating within a renal allograft five years following resolution of polyoma virus nephropathy.

    Science.gov (United States)

    Salvatore, Steven P; Myers-Gurevitch, Patricia M; Chu, Stacy; Robinson, Brian D; Dadhania, Darshana; Seshan, Surya V

    2016-03-01

    A direct role for BK polyomavirus infection in malignant tumors of renal allografts and urinary tract is emerging. Case reports suggest a link between BK virus (BKV) reactivation and development of malignancy in renal allograft recipients. Herein we describe the first case of BKV positive invasive urothelial carcinoma within the renal allograft, presenting with chronic diarrhea and weight loss 5 years following resolution of BK viremia/nephropathy (BKVN). Unique to our case was the remote history of BK viremia/BKVN, rising titer of anti-HLA antibody and presence of renal limited urothelial carcinoma with microinvasion of malignant cells staining positive for SV40 large T antigen (T-Ag). These findings suggest that persistence of subclinical BKV infection within the renal allograft may play a role in the malignant transformation of epithelial cells. Patients with history of BKVN may be at risk for kidney and urinary tract malignancy despite resolution of BK viremia/BKVN.

  5. IL-12p40 is not required for islet allograft rejection

    Institute of Scientific and Technical Information of China (English)

    En-guang BI; Wei SHI; Jia ZOU; Zhen-hua HAO; Zhen-hu LI; Duan CAI; Hua-qun ZHANG; Bing SUN

    2006-01-01

    Aim: To investigate whether IL-12p40 plays a crucial role in regulating islet allograft rejection in a streptozotocin (STZ)-induced diabetes mouse model. Methods: C57BL/6 and IL-12p40 gene knockout mice were selected as recipient mice, to which the diabetes was induced with a treatment of STZ (150-200 mg/kg) by a single ip injection. BALB/c mice were selected as donor mice and islet cells were isolated from the mice. The 500 islets were transplanted into recipient mice beneath the capsule of the left kidney. Following the islet transplantation the glucose from the mice sera was monitored and the rejection rate of islets was analyzed. Results: STZ could induce diabetes in the recipient mice within 1 week. After transplantation of allograft islets, the increased glucose in wild-type (WT) mice returned to normal level and was maintained for 10 d. Unexpectedly, the rejection rate of islet allograft between IL-12p40-deficient mice and WT mice was similar. Conclusion: The results suggested that, although islet allograft rejection is believed to be Th1-cell predominant, the Th1 response inducer, IL-12 and IL-23 are not essential to induce islet allograft rejection.

  6. MicroRNA-10b downregulation mediates acute rejection of renal allografts by derepressing BCL2L11

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaoyou [Department of Organ Transplantation, Zhujiang Hospital, Guangzhou 510282 (China); Dong, Changgui [Institute of Molecular Ecology and Evolution, East China Normal University, Shanghai 200062 (China); Jiang, Zhengyao [Department of Organ Transplantation, Zhujiang Hospital, Guangzhou 510282 (China); Wu, William K.K. [Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); State Key Laboratory of Digestive Diseases, LKS Institute of Health Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Chan, Matthew T.V. [Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Zhang, Jie [Department of Organ Transplantation, Zhujiang Hospital, Guangzhou 510282 (China); Li, Haibin; Qin, Ke [Guangxi Key Laboratory for Transplantation Medicine Department of Organ Transplantation in Guangzhou Military Region, Institute of Transplant Medicine, 303 Hospital of People' s Liberation Army, Nanning, Guangxi 530021 (China); Sun, Xuyong, E-mail: sunxuyong0528@163.com [Guangxi Key Laboratory for Transplantation Medicine Department of Organ Transplantation in Guangzhou Military Region, Institute of Transplant Medicine, 303 Hospital of People' s Liberation Army, Nanning, Guangxi 530021 (China)

    2015-04-10

    Kidney transplantation is the major therapeutic option for end-stage kidney diseases. However, acute rejection could cause allograft loss in some of these patients. Emerging evidence supports that microRNA (miRNA) dysregulation is implicated in acute allograft rejection. In this study, we used next-generation sequencing to profile miRNA expression in normal and acutely rejected kidney allografts. Among 75 identified dysregulated miRNAs, miR-10b was the most significantly downregulated miRNAs in rejected allografts. Transfecting miR-10b inhibitor into human renal glomerular endothelial cells recapitulated key features of acute allograft rejection, including endothelial cell apoptosis, release of pro-inflammatory cytokines (interleukin-6, tumor necrosis factor α, interferon-γ, and chemokine (C–C motif) ligand 2) and chemotaxis of macrophages whereas transfection of miR-10b mimics had opposite effects. Downregulation of miR-10b directly derepressed the expression of BCL2L11 (an apoptosis inducer) as revealed by luciferase reporter assay. Taken together, miR-10b downregulation mediates many aspects of disease pathogenicity of acute kidney allograft rejection. Restoring miR-10b expression in glomerular endothelial cells could be a novel therapeutic approach to reduce acute renal allograft loss. - Highlights: • miR-10b was the most downregulated microRNAs in acutely rejected renal allografts. • miR-10b downregulation triggered glomerular endothelial cell apoptosis. • miR-10b downregulation induced release of pro-inflammatory cytokines. • miR-10b downregulation derepressed its pro-apoptotic target BCL2L11.

  7. Reconstruction of Multiple Facial Nerve Branches Using Skeletal Muscle-Derived Multipotent Stem Cell Sheet-Pellet Transplantation.

    Directory of Open Access Journals (Sweden)

    Kosuke Saito

    Full Text Available Head and neck cancer is often diagnosed at advanced stages, and surgical resection with wide margins is generally indicated, despite this treatment being associated with poor postoperative quality of life (QOL. We have previously reported on the therapeutic effects of skeletal muscle-derived multipotent stem cells (Sk-MSCs, which exert reconstitution capacity for muscle-nerve-blood vessel units. Recently, we further developed a 3D patch-transplantation system using Sk-MSC sheet-pellets. The aim of this study is the application of the 3D Sk-MSC transplantation system to the reconstitution of facial complex nerve-vascular networks after severe damage. Mouse experiments were performed for histological analysis and rats were used for functional examinations. The Sk-MSC sheet-pellets were prepared from GFP-Tg mice and SD rats, and were transplanted into the facial resection model (ST. Culture medium was transplanted as a control (NT. In the mouse experiment, facial-nerve-palsy (FNP scoring was performed weekly during the recovery period, and immunohistochemistry was used for the evaluation of histological recovery after 8 weeks. In rats, contractility of facial muscles was measured via electrical stimulation of facial nerves root, as the marker of total functional recovery at 8 weeks after transplantation. The ST-group showed significantly higher FNP (about three fold scores when compared to the NT-group after 2-8 weeks. Similarly, significant functional recovery of whisker movement muscles was confirmed in the ST-group at 8 weeks after transplantation. In addition, engrafted GFP+ cells formed complex branches of nerve-vascular networks, with differentiation into Schwann cells and perineurial/endoneurial cells, as well as vascular endothelial and smooth muscle cells. Thus, Sk-MSC sheet-pellet transplantation is potentially useful for functional reconstitution therapy of large defects in facial nerve-vascular networks.

  8. Hyperlipidemia Promotes Anti-Donor Th17 Responses That Accelerate Allograft Rejection.

    Science.gov (United States)

    Yuan, J; Bagley, J; Iacomini, J

    2015-09-01

    Hyperlipidemia occurs in 95% of organ transplant recipients, however its effect on organ allograft rejection has not been investigated. We found that induction of hyperlipidemia in mice caused a significant acceleration of rejection of cardiac allografts. Accelerated rejection was associated with an aggressive T cell infiltrate that mediated significant tissue damage as well as increased serum levels of the proinflammatory cytokines IL-2, IL-6, and IL-17. Hyperlipidemic mice had an increased number of Th17 cells in their periphery and rejecting allografts from hyperlipidemic mice contained significant numbers of IL-17 producing T cells that were not detectable in transplants harvested from controls. Neutralization or genetic ablation of IL-17 prolonged survival of cardiac allografts transplanted into hyperlipidemic recipients, suggesting that IL-17 production promotes accelerated rejection. Analysis of alloreactive T cell frequencies directly ex vivo in naïve mice revealed that the frequency of donor reactive IL-17 producing cells in hyperlipidemic was increased prior to antigen exposure, suggesting that hyperlipidemia was sufficient to alter T cell alloreactivity and promote anti-donor Th17 responses on first exposure to antigen. Together, our data suggest that hyperlipidemia alters rejection by altering the types of T cell subsets that respond to donor antigen by promoting Th17 biased anti-donor reactivity.

  9. How to prevent contamination with Candida albicans during the fabrication of transplantable oral mucosal epithelial cell sheets

    Directory of Open Access Journals (Sweden)

    Ryo Takagi

    2015-06-01

    Full Text Available We have utilized patients' own oral mucosa as a cell source for the fabrication of transplantable epithelial cell sheets to treat limbal stem cell deficiency and mucosal defects after endoscopic submucosal dissection of esophageal cancer. Because there are abundant microbiotas in the human oral cavity, the oral mucosa was sterilized and 40 μg/mL gentamicin and 0.27 μg/mL amphotericin B were added to the culture medium in our protocol. Although an oral surgeon carefully checked each patient's oral cavity and although candidiasis was not observed before taking the biopsy, contamination with Candida albicans (C. albicans was detected in the conditioned medium during cell sheet fabrication. After adding 1 μg/mL amphotericin B to the transportation medium during transport from Nagasaki University Hospital to Tokyo Women's Medical University, which are 1200 km apart, no proliferation of C. albicans was observed. These results indicated that the supplementation of transportation medium with antimycotics would be useful for preventing contamination with C. albicans derived from the oral mucosa without hampering cell proliferation.

  10. Recipient Myd88 Deficiency Promotes Spontaneous Resolution of Kidney Allograft Rejection.

    Science.gov (United States)

    Lerret, Nadine M; Li, Ting; Wang, Jiao-Jing; Kang, Hee-Kap; Wang, Sheng; Wang, Xueqiong; Jie, Chunfa; Kanwar, Yashpal S; Abecassis, Michael M; Luo, Xunrong; Zhang, Zheng

    2015-11-01

    The myeloid differentiation protein 88 (MyD88) adapter protein is an important mediator of kidney allograft rejection, yet the precise role of MyD88 signaling in directing the host immune response toward the development of kidney allograft rejection remains unclear. Using a stringent mouse model of allogeneic kidney transplantation, we demonstrated that acute allograft rejection occurred equally in MyD88-sufficient (wild-type [WT]) and MyD88(-/-) recipients. However, MyD88 deficiency resulted in spontaneous diminution of graft infiltrating effector cells, including CD11b(-)Gr-1(+) cells and activated CD8 T cells, as well as subsequent restoration of near-normal renal graft function, leading to long-term kidney allograft acceptance. Compared with T cells from WT recipients, T cells from MyD88(-/-) recipients failed to mount a robust recall response upon donor antigen restimulation in mixed lymphocyte cultures ex vivo. Notably, exogenous IL-6 restored the proliferation rate of T cells, particularly CD8 T cells, from MyD88(-/-) recipients to the proliferation rate of cells from WT recipients. Furthermore, MyD88(-/-) T cells exhibited diminished expression of chemokine receptors, specifically CCR4 and CXCR3, and the impaired ability to accumulate in the kidney allografts despite an otherwise MyD88-sufficient environment. These results provide a mechanism linking the lack of intrinsic MyD88 signaling in T cells to the effective control of the rejection response that results in spontaneous resolution of acute rejection and long-term graft protection.

  11. Currently available useful immunohistochemical markers of renal pathology for the diagnosis of renal allograft rejection.

    Science.gov (United States)

    Kanzaki, Go; Shimizu, Akira

    2015-07-01

    Renal allograft dysfunction may be induced by various causes, including alloimmune rejection, viral infection, urinary tract obstruction, calcineurin inhibitor nephrotoxicity and/or recurrent renal disease. In order to determine the underlying cause, a renal biopsy is performed and the renal transplant pathology is diagnosed using the internationally consensus Banff classification. Although a progressive understanding of allograft rejection has provided numerous immunohistochemical markers, only the C4d is regarded to be a sufficiently useful marker for antibody-mediated allograft rejection according to the Banff classification. This review summarizes currently available useful immunohistochemical markers of renal transplant pathology, including C4d, with diagnostic implications for human renal allograft rejection. In particular, we discuss immunohistochemical markers in the following three categories: immunohistochemical markers of renal pathology used to (i) analyze the mechanisms of alloimmune rejection, (ii) monitor cell injury and/or inflammation associated with rejection and (iii) identify renal components in order to improve the diagnosis of rejection. In addition, recent progress in the field of renal transplant pathology includes the development of a new method for assessing molecular pathology using OMICS analyses. As the recent findings of various studies in patients undergoing renal transplantation are very encouraging, novel immunohistochemical markers must be also developed and combined with new technologies for the diagnosis of human renal allograft rejection.

  12. Comparative study and histomorphometric analysis of bone allografts lyophilized and sterilized by autoclaving, gamma irradiation and ethylene oxide in rats

    Directory of Open Access Journals (Sweden)

    Otavio Machado de Almeida

    2013-01-01

    Full Text Available PURPOSE: To compare three sterilization methods (autoclave, gamma irradiation and ethylene oxide over non demineralized lyophilized bone allografts. METHODS: Bone allografts were implanted on paravertebral muscles of 21 rats. After 30 days animals were sacrificed and grafts underwent comparative analysis regarding histomorphometric and macroscopic parameters. RESULTS: Allografts that underwent the three sterilization methods presents similar weight gain, cortical thickness similar to control group, and less fibrosis than the control group. Grafts that underwent sterilization in autoclave presented less presence of multinucleated giant cells, although not statistically significant. There was also no statistically significant difference regarding mineralization on the three groups. CONCLUSION: The three sterilization methods cause similar effects on bone allografts regarding macroscopic and histomorphometric parameters.

  13. CD160Ig fusion protein targets a novel costimulatory pathway and prolongs allograft survival.

    Directory of Open Access Journals (Sweden)

    Francesca D'Addio

    Full Text Available CD160 is a cell surface molecule expressed by most NK cells and approximately 50% of CD8(+ cytotoxic T lymphocytes. Engagement of CD160 by MHC class-I directly triggers a costimulatory signal to TCR-induced proliferation, cytokine production and cytotoxic effector functions. The role of CD160 in alloimmunity is unknown. Using a newly generated CD160 fusion protein (CD160Ig we examined the role of the novel costimulatory molecule CD160 in mediating CD4(+ or CD8(+ T cell driven allograft rejection. CD160Ig inhibits alloreactive CD8(+ T cell proliferation and IFN-γ production in vitro, in particular in the absence of CD28 costimulation. Consequently CD160Ig prolongs fully mismatched cardiac allograft survival in CD4(-/-, CD28(-/- knockout and CTLA4Ig treated WT recipients, but not in WT or CD8(-/- knockout recipients. The prolonged cardiac allograft survival is associated with reduced alloreactive CD8(+ T cell proliferation, effector/memory responses and alloreactive IFN-γ production. Thus, CD160 signaling is particularly important in CD28-independent effector/memory CD8(+ alloreactive T cell activation in vivo and therefore may serve as a novel target for prevention of allograft rejection.

  14. Light-sheet Bayesian microscopy enables deep-cell super-resolution imaging of heterochromatin in live human embryonic stem cells

    Science.gov (United States)

    Hu, Ying S; Zhu, Quan; Elkins, Keri; Tse, Kevin; Li, Yu; Fitzpatrick, James A J; Verma, Inder M; Cang, Hu

    2016-01-01

    Background Heterochromatin in the nucleus of human embryonic cells plays an important role in the epigenetic regulation of gene expression. The architecture of heterochromatin and its dynamic organization remain elusive because of the lack of fast and high-resolution deep-cell imaging tools. We enable this task by advancing instrumental and algorithmic implementation of the localization-based super-resolution technique. Results We present light-sheet Bayesian super-resolution microscopy (LSBM). We adapt light-sheet illumination for super-resolution imaging by using a novel prism-coupled condenser design to illuminate a thin slice of the nucleus with high signal-to-noise ratio. Coupled with a Bayesian algorithm that resolves overlapping fluorophores from high-density areas, we show, for the first time, nanoscopic features of the heterochromatin structure in both fixed and live human embryonic stem cells. The enhanced temporal resolution allows capturing the dynamic change of heterochromatin with a lateral resolution of 50–60 nm on a time scale of 2.3 s. Conclusion Light-sheet Bayesian microscopy opens up broad new possibilities of probing nanometer-scale nuclear structures and real-time sub-cellular processes and other previously difficult-to-access intracellular regions of living cells at the single-molecule, and single cell level.

  15. Genetics and Epigenetics of Chronic Allograft Dysfunction in Kidney Transplants.

    Science.gov (United States)

    Zununi Vahed, Sepideh; Samadi, Nasser; Mostafidi, Elmira; Ardalan, Mohammad Reza; Omidi, Yadollah

    2016-01-01

    Chronic allograft dysfunction is the most common cause of allograft lost. Chronic allograft dysfunction happens as a result of complex interactions at the molecular and cellular levels. Genetic and environmental factors both influence the evolution and progression of the chronic allograft dysfunction. Epigenetic modification could be considered as a therapeutically modifiable element to pause the fibrosis process through novel strategies. In this review, the PubMed database was searched for English-language articles on these new areas.

  16. Graft enhancement and antiidiotypic antibody. Lymphocytes from long-term rat renal allograft recipients have normal responsiveness in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Fitch, F.W.; Weiss, A.; McKearn, T.J.; Stuart, F.P.

    1978-06-01

    Treatment of allograft recipients with antigen Ag and antibody Ab causes a transient appearance of anti-Id antibody, and kidneys transplanted at the time of peak anti-Id response fare better than those transplanted earlier or later. Since these observations suggested a role for anti-Id Ab in rat renal allograft enhancement, the immunologic reactivity of lymphocytes from animals bearing long-term, enhanced renal allografts was studied. The survival of long-term enhanced renal allografts remains an enigma. Although anti-Id Ab is produced as a result of the initial treatment used for induction of enhancement, such Ab is not detected in long-term recipients. The reactivity of cells from such recipients is not that reported for animals actively producing anti-Id Ab. The responsiveness of lymphocytes in vitro from long-term allograft recipients appears to be normal, not increased as observed in sensitized rats or absent as observed in neonatally tolerant rats. It is not known why these cells fail to respond to graft antigens in the enhanced allograft recipient. Inhibitory processes that function in the intact animal seem to be inactive in the experimental systems used for measurement of lymphocyte responsiveness in culture.

  17. Experi mental Study on Preparation of Decellularized Artery Vascular Graftand Transplantation of Carotid Artery Allografts

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionRemoval of cells may decrease the antigenicity of artery allografts and xenografts~([1~3]). This study was to set up a new process to prepare the decellularized artery grafts. And the feasibility of small diameter decellularized artery allografts in vivo was evaluate. 2 Materials and Methods2.1 Set up a new processA four-step process, including hypotonic, hypertonic solutions and combining with 1% t-octyl-phenoxypolyethoxyethanol (Triton X-100) and 1% sodium dodecyl sulfate (SDS) detergents, w...

  18. Immediate retransplantation for pancreas allograft thrombosis.

    Science.gov (United States)

    Hollinger, E F; Powelson, J A; Mangus, R S; Kazimi, M M; Taber, T E; Goble, M L; Fridell, J A

    2009-04-01

    Early pancreas allograft failure most commonly results from thrombosis and requires immediate allograft pancreatectomy. Optimal timing for retransplantation remains undefined. Immediate retransplantation facilitates reuse of the same anatomic site before extensive adhesions have formed. Some studies suggest that early retransplantation is associated with a higher incidence of graft loss. This study is a retrospective review of immediate pancreas retransplants performed at a single center. All cases of pancreas allograft loss within 2 weeks were examined. Of 228 pancreas transplants, 12 grafts were lost within 2 weeks of surgery. Eleven of these underwent allograft pancreatectomy for thrombosis. One suffered anoxic brain injury and was not a retransplantation candidate, one was retransplanted at 3.5 months and nine patients underwent retransplantation 1-16 days following the original transplant. Of the nine early retransplants, one pancreas was lost to heparin-induced thrombocytopenia, one recipient died with function at 2.9 years and the other grafts continue to function at 76-1137 days (mean 572 days). One-year graft survival for early retransplantation was 89% compared to 91% for all pancreas transplants at our center. Immediate retransplantation following pancreatic graft thrombosis restores durable allograft function with outcomes comparable to first-time pancreas transplantation.

  19. Radionuclide surveillance of the allografted pancreas

    Energy Technology Data Exchange (ETDEWEB)

    George, E.A.; Salimi, Z.; Carney, K.; Castaneda, M.; Garvin, P.J.

    1988-04-01

    To determine the value of scintigraphy to detect posttransplantation complications of the allografted pancreas, we retrospectively reviewed 209 scintigrams obtained with /sup 99m/Tc-sulfur colloid (/sup 99m/Tc-SC) and /sup 99m/Tc-glucoheptonate (/sup 99m/Tc-GH). The scintigraphic studies were performed in 37 recipients of simultaneous renal and pancreatic allografts harvested from the same donor. /sup 99m/Tc-SC was used as an indicator of thrombotic vasculitis; pancreatic perfusion and blood-pool parameters were monitored with /sup 99m/Tc-GH. In 11 of the 37 recipients, scintigraphic abnormalities suggested posttransplantation infarction. Recurrent episodes of acute rejection of the pancreatic allograft, which always coincided with acute rejection of the renal allograft, were monitored in 24 recipients. Rejection-induced ischemic pancreatitis was suggested in 12 of the 24 recipients and persisted in 10 recipients for several weeks after improvement of renal allograft rejection. Pancreatic atrophy was suggested scintigraphically in 16 of the 24 recipients with recurrent episodes of rejection. Spontaneous pancreatic-duct obstruction and obstructive pancreatitis were associated with a scintigraphic pattern similar to that of rejection-induced ischemic pancreatitis. We concluded that the specific radionuclides used in this series are useful for the surveillance and assessment of posttransplantation pancreatic infarction, acute rejection, pancreatitis, and atrophy

  20. Calprotectin - A novel noninvasive marker for intestinal allograft monitoring

    NARCIS (Netherlands)

    Sudan, Debra; Vargas, Luciano; Sun, Yimin; Bok, Lisette; Dijkstra, Gerard; Langnas, Alan

    2007-01-01

    Objective: To identify a noninvasive screening test for intestinal allograft monitoring. Summary Background Data: Intestinal allograft rejection is difficult to distinguish from other causes of diarrhea and can rapidly lead to severe exfoliation or death. Protocol biopsies are standard for allograft

  1. Rapid cell sheet detachment using spin-coated pNIPAAm films retained on surfaces by an aminopropyltriethoxysilane network.

    Science.gov (United States)

    Patel, Nikul G; Cavicchia, John P; Zhang, Ge; Zhang Newby, Bi-min

    2012-07-01

    The ability to harvest cell sheets grown on thermoresponsive polymers, such as poly(N-isopropylacrylamide) (pNIPAAm), has been widely studied for use in tissue engineering applications. pNIPAAm is of special interest because of the phase change that it undergoes in a physiologically relevant temperature range. Two primary approaches have been adopted to graft pNIPAAm chains covalently onto tissue culture polystyrene dishes: electron beam irradiation and plasma polymerization. These approaches often involve non-easily accessible (e.g. e-beam) facilities and complicated procedures that have hindered most tissue culture laboratories in adopting this technology for their specific applications. In this study, we developed a simple and cost-effective approach to create thermoresponsive surfaces using commercially available pNIPAAm. Using a simple spin-coating technique, thermoresponsive thin films were deposited on glass slides or silicon wafers using pNIPAAm blended with a small amount of 3-aminopropyltriethoxysilane (APTES), which enhances the retention of pNIPAAm on the surface. We found that the thermoresponsive films created using our method support cell attachment and proliferation without additional adhesive proteins as well as cell sheet detachment within minutes.

  2. Cytomegalovirus-Associated CD4(+) CD28(null) Cells in NKG2D-Dependent Glomerular Endothelial Injury and Kidney Allograft Dysfunction.

    Science.gov (United States)

    Shabir, S; Smith, H; Kaul, B; Pachnio, A; Jham, S; Kuravi, S; Ball, S; Chand, S; Moss, P; Harper, L; Borrows, R

    2016-04-01

    Emerging data suggest that expansion of a circulating population of atypical, cytotoxic CD4(+) T cells lacking costimulatory CD28 (CD4(+) CD28(null) cells) is associated with latent cytomegalovirus (CMV) infection. The purpose of the current study was to increase the understanding of the relevance of these cells in 100 unselected kidney transplant recipients followed prospectively for a median of 54 months. Multicolor flow cytometry of peripheral blood mononuclear cells before transplantation and serially posttransplantation was undertaken. CD4(+) CD28(null) cells were found predominantly in CMV-seropositive patients and expanded in the posttransplantation period. These cells were predominantly effector-memory phenotype and expressed markers of endothelial homing (CX3CR1) and cytotoxicity (NKG2D and perforin). Isolated CD4(+) CD27(-) CD28(null) cells proliferated in response to peripheral blood mononuclear cells previously exposed to CMV-derived (but not HLA-derived) antigens and following such priming incubation with glomerular endothelium resulted in signs of endothelial damage and apoptosis (release of fractalkine and von Willebrand factor; increased caspase 3 expression). This effect was mitigated by NKG2D-blocking antibody. Increased CD4(+) CD28(null) cell frequencies were associated with delayed graft function and lower estimated glomerular filtration rate at end follow-up. This study suggests an important role for this atypical cytotoxic CD4(+) CD28(null) cell subset in kidney transplantation and points to strategies that may minimize the impact on clinical outcomes.

  3. Urinary calprotectin and posttransplant renal allograft injury

    DEFF Research Database (Denmark)

    Tepel, Martin; Borst, Christoffer; Bistrup, Claus

    2014-01-01

    OBJECTIVE: Current methods do not predict the acute renal allograft injury immediately after kidney transplantation. We evaluated the diagnostic performance of urinary calprotectin for predicting immediate posttransplant allograft injury. METHODS: In a multicenter, prospective-cohort study of 144...... incipient renal transplant recipients, we postoperatively measured urinary calprotectin using an enzyme-linked immunosorbent assay and estimated glomerular filtration rate (eGFR) after 4 weeks, 6 months, and 12 months. RESULTS: We observed a significant inverse association of urinary calprotectin...... regression showed that higher urinary calprotectin concentrations and older donor age predicted lower eGFR four weeks, 6 months, and 12 months after transplantation. CONCLUSIONS: Urinary calprotectin is an early, noninvasive predictor of immediate renal allograft injury after kidney transplantation....

  4. Chronic Kidney Isograft and Allograft Rejection

    Institute of Scientific and Technical Information of China (English)

    严群; 张鹏; 杨传永

    2002-01-01

    Summary: In this study antigen-independent factor in the pathogenesis of chronic rejection of organ transplants was examined. Kidney isografts and allografts were transplanted orthotopically into bilaterally nephroectomized rat recipients and studied functionally, morphologically and immunohistologically, at serial intervals up to 52 weeks after transplantation. Allograft recipients developed progressive proteinuria after 12 weeks, with gradual renal failure ultimately leading to death. At the same time, morphological changes, including progressive arteriosclerosis and glomerulosclerosis, tubular atrophy and interstitial fibrosis, developed. Immunohistologically, macrophages infiltrated glomeruli during this period and cytokines became unregulated. Our resuits showed that antigen-independent functional and morphological changes occurred in long-term kidney isografts and mimicked those appearing much earlier in allografts that reject chronically.Initial injury and extent of functioning renal mass is suggested to be important factor for such late changes.

  5. Allogeneic Transplantation of an Adipose-Derived Stem Cell Sheet Combined With Artificial Skin Accelerates Wound Healing in a Rat Wound Model of Type 2 Diabetes and Obesity.

    Science.gov (United States)

    Kato, Yuka; Iwata, Takanori; Morikawa, Shunichi; Yamato, Masayuki; Okano, Teruo; Uchigata, Yasuko

    2015-08-01

    One of the most common complications of diabetes is diabetic foot ulcer. Diabetic ulcers do not heal easily due to diabetic neuropathy and reduced blood flow, and nonhealing ulcers may progress to gangrene, which necessitates amputation of the patient's foot. This study attempted to develop a new cell-based therapy for nonhealing diabetic ulcers using a full-thickness skin defect in a rat model of type 2 diabetes and obesity. Allogeneic adipose-derived stem cells (ASCs) were harvested from the inguinal fat of normal rats, and ASC sheets were created using cell sheet technology and transplanted into full-thickness skin defects in Zucker diabetic fatty rats. The results indicate that the transplantation of ASC sheets combined with artificial skin accelerated wound healing and vascularization, with significant differences observed 2 weeks after treatment. The ASC sheets secreted large amounts of several angiogenic growth factors in vitro, and transplanted ASCs were observed in perivascular regions and incorporated into the newly constructed vessel structures in vivo. These results suggest that ASC sheets accelerate wound healing both directly and indirectly in this diabetic wound-healing model. In conclusion, allogeneic ASC sheets exhibit potential as a new therapeutic strategy for the treatment of diabetic ulcers.

  6. Larger number of invariant natural killer T cells in PBSC allografts correlates with improved GVHD-free and progression-free survival.

    Science.gov (United States)

    Malard, Florent; Labopin, Myriam; Chevallier, Patrice; Guillaume, Thierry; Duquesne, Alix; Rialland, Fanny; Derenne, Sophie; Peterlin, Pierre; Leauté, Anne-Gaelle; Brissot, Eolia; Gregoire, Marc; Moreau, Philippe; Saas, Philippe; Gaugler, Béatrice; Mohty, Mohamad

    2016-04-01

    We studied the impact of a set of immune cells contained within granulocyte colony-stimulating factor-mobilized peripheral blood stem cell grafts (naïve and memory T-cell subsets, B cells, regulatory T cells, invariant natural killer T cells [iNKTs], NK cells, and dendritic cell subsets) in patients (n = 80) undergoing allogeneic stem cell transplantation (SCT), using the composite end point of graft-versus-host disease (GVHD)-free and progression-free survival (GPFS) as the primary end point. We observed that GPFS incidences in patients receiving iNKT doses above and below the median were 49% vs 22%, respectively (P= .007). In multivariate analysis, the iNKT dose was the only parameter with a significant impact on GPFS (hazard ratio = 0.48; 95% confidence interval, 0.27-0.85;P= .01). The incidences of severe grade III to IV acute GVHD and National Institutes of Health grade 2 to 3 chronic GVHD (12% and 16%, respectively) were low and associated with the use of antithymocyte globulin in 91% of patients. No difference in GVHD incidence was reported according to the iNKT dose. In conclusion, a higher dose of iNKTs within the graft is associated with an improved GPFS. These data may pave the way for prospective and active interventions aiming to manipulate the graft content to improve allo-SCT outcome.

  7. Reversal of Diabetes by Islet Transplantation: Vulnerability of the Established Allograft

    Science.gov (United States)

    Bowen, K. M.; Prowse, S. J.; Lafferty, K. J.

    1981-09-01

    Nonspecific stimulation of the immune system of CBA mice carrying a functional BALB/c islet allograft failed to trigger graft rejection. Only three of six animals rejected their graft when injected intravenously with 105, 106, and 107 peritoneal cells of BALB/c origin over a 3-month period commencing 100 days after transplantation.

  8. Increased Expression of p-Akt correlates with Chronic Allograft Nephropathy in a Rat Kidney Model.

    Science.gov (United States)

    Zhou, Li-Na; Wang, Ning; Dong, Yang; Zhang, Yiqin; Zou, Hequn; Li, Qingqin; Shi, Yangling; Chen, Ling; Zhou, Wenying; Han, Conghui; Wang, Yuxin

    2015-04-01

    Chronic allograft nephropathy (CAN) is the most common cause of chronic graft dysfunction leading to graft failure, our study investigates the expression and significance of p-Akt in the pathogenesis of CAN in rats. Kidneys of Fisher (F344) rats were orthotopically transplanted into Lewis (LEW) rats. The animals were evaluated at 4, 8, 12, 16, and 24 weeks post-transplantation for renal function and histopathology. Phosphorate Akt (p-Akt) protein expression was determined by Western blot and immunohistological assays. Our data show that 24-h urinary protein excretion in CAN rats increased significantly at week 16 as compared with F344/LEW controls. Allografts got severe interstitial infiltration of mononuclear cells at week 4 and week 8, but it was degraded as the time went on after week 16. Allografts markedly presented with severe interstitial fibrosis (IF) and tubular atrophy at 16 and 24 weeks. p-Akt expression was upregulated in rat kidneys with CAN, and the increase became more significant over time after transplantation. p-Akt expression correlated significantly with 24-h urinary protein excretion, serum creatinine levels, tubulointerstitial mononuclear cells infiltration, smooth muscle cells (SMCs) migration in vascular wall, and IF. It was concluded that p-Akt overexpression might be the key event that involved mononuclear cells infiltration and vascular SMCs migration at early stage, and IF and allograft nephroangiosclerosis at the late stage of CAN pathogenesis in rats.

  9. Kidney injury molecule-1 expression is closely associated with renal allograft damage.

    Science.gov (United States)

    Song, Lianlian; Xue, Lijuan; Yu, Jinyu; Zhao, Jun; Zhang, Wenlan; Fu, Yaowen

    2013-08-01

    The aim of our study was to investigate the expression of kidney injury molecule-1 (KIM-1) in renal allograft biopsy samples and assess the clinical significance of its use as a biomarker for tissue damage. A total of 69 renal allograft biopsy samples from 17 patients with normal serum creatinine and 52 cases of increased serum creatinine were collected. They were divided into different groups according to the Banff 2007 diagnostic criteria. KIM-1 expression was detected by immunohistochemical methods and the association of KIM-1 and blood biochemical indexes was analyzed. KIM-1 expression increased as Banff 2007 classification grade increased and was positively correlated with tubular inflammation severity in the acute T-cell rejection group. Moreover, KIM-1 expression was strongly positive in the chronic active antibody-mediated rejection group. Interestingly, KIM-1 was weakly positive in the normal group without obvious acute rejection and injury of immunosuppressant toxicity. In this group, 27.3% (3/11) of the cases with normal serum creatinine level showed weakly positive KIM-1 expression in their renal tissues. KIM-1 expression level is positively correlated with renal allograft damage and tubular cell injury. KIM-1 is expressed in tubular epithelial cells before blood biochemical indexes become elevated and morphological changes occur. KIM-1 expression is an early, sensitive, and specific biomarker to determine renal tubular epithelial cell injury in renal allograft tissue.

  10. Optimal Materials and Deposition Technique Lead to Cost-Effective Solar Cell with Best-Ever Conversion Efficiency (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-07-01

    This fact sheet describes how the SJ3 solar cell was invented, explains how the technology works, and why it won an R&D 100 Award. Based on NREL and Solar Junction technology, the commercial SJ3 concentrator solar cell - with 43.5% conversion efficiency at 418 suns - uses a lattice-matched multijunction architecture that has near-term potential for cells with {approx}50% efficiency. Multijunction solar cells have higher conversion efficiencies than any other type of solar cell. But developers of utility-scale and space applications crave even better efficiencies at lower costs to be both cost-effective and able to meet the demand for power. The SJ3 multijunction cell, developed by Solar Junction with assistance from foundational technological advances by the National Renewable Energy Laboratory, has the highest efficiency to date - almost 2% absolute more than the current industry standard multijunction cell-yet at a comparable cost. So what did it take to create this cell having 43.5% efficiency at 418-sun concentration? A combination of materials with carefully designed properties, a manufacturing technique allowing precise control, and an optimized device design.

  11. Hyaluronic acid concentration-mediated changes in structure and function of porous carriers for corneal endothelial cell sheet delivery.

    Science.gov (United States)

    Lai, Jui-Yang

    2016-02-01

    In this study, the effects of hyaluronic acid (HA) concentrations (0.05-1.25wt.%) on the properties of porous carriers for corneal endothelial tissue engineering were investigated. The pore size and porosity gradually increased with decreasing solid content. However, at relatively low HA concentration (i.e., 0.05wt.%), the material samples contained small interior pores and a dense surface skin layer, probably due to no gas bubble effect on the stirring processing of porous microstructures of freeze-dried polysaccharide hydrogels. The carriers prepared from 0.25wt.% HA solution had the highest freezable water content and oxygen and glucose permeability among the samples evaluated. Results of cell viability assays and quantitative real-time reverse transcription polymerase chain reaction analyses showed that the HA concentration-related alteration of porous microstructure dictates the compatibility of biopolymer carriers with corneal endothelial cell (CEC) cultures. In vivo studies demonstrated that the CEC sheet/HA carrier construct implants are therapeutically efficacious in the reconstruction of endothelial scrape-wounded corneas. It is concluded that the polysaccharide concentration is the major factor for affecting the processing of carriers and their structure and function. Porous hydrogels prepared from 0.25wt.% HA solution are capable of delivering bioengineered CEC sheets to the posterior surface of cornea.

  12. Impaired elastin deposition in Fstl1-/- lung allograft under the renal capsule.

    Directory of Open Access Journals (Sweden)

    Yan Geng

    Full Text Available Lung alveolar development in late gestation is a process important to postnatal survival. Follistatin-like 1 (Fstl1 is a matricellular protein of the Bmp antagonist class, which is involved in the differentiation/maturation of alveolar epithelial cells during saccular stage of lung development. This study investigates the role of Fstl1 on elastin deposition in mesenchyme and subsequent secondary septation in the late gestation stage of terminal saccular formation. To this aim, we modified the renal capsule allograft model for lung organ culture by grafting diced E15.5 distal lung underneath the renal capsule of syngeneic host and cultured up to 7 days. The saccular development of the diced lung allografts, as indicated by the morphology, epithelial and vascular developments, occurred in a manner similar to that in utero. Fstl1 deficiency caused atelectatic phenotype companied by impaired epithelial differentiation in D3 Fstl1(-/- lung allografts, which is similar to that of E18.5 Fstl1(-/- lungs, supporting the role of Fstl1 during saccular stage. Inhibition of Bmp signaling by intraperitoneal injection of dorsomorphin in the host mice rescued the pulmonary atelectasis of D3 Fstl1(-/- allografts. Furthermore, a marked reduction in elastin expression and deposition was observed in walls of air sacs of E18.5 Fstl1(-/- lungs and at the tips of the developing alveolar septae of D7 Fstl1(-/- allografts. Thus, in addition to its role on alveolar epithelium, Fstl1 is crucial for elastin expression and deposition in mesenchyme during lung alveologenesis. Our data demonstrates that the modified renal capsule allograft model for lung organ culture is a robust and efficient technique to increase our understanding of saccular stage of lung development.

  13. Poly(N-isopropylacrylamide) surface-grafted chitosan membranes as a new substrate for cell sheet engineering and manipulation.

    Science.gov (United States)

    da Silva, Ricardo M P; López-Pérez, Paula M; Elvira, Carlos; Mano, João F; Román, Julio San; Reis, Rui L

    2008-12-15

    The immobilization of poly(N-isopropylacrylamide) (PNIPAAm) on chitosan membranes was performed in order to render membranes with thermo-responsive surface properties. The aim was to create membranes suitable for cell culture and in which confluent cell sheets can be recovered by simply lowering the temperature. The chitosan membranes were immersed in a solution of the monomer that was polymerized via radical initiation. The composition of the polymerization reaction solvent, which was a mixture of a chitosan non-solvent (isopropanol) and a solvent (water), provided a tight control over the chitosan membranes swelling capability. The different swelling ratio, obtained at different solvent composition of the reaction mixture, drives simultaneously the monomer solubility and diffusion into the polymeric matrix, the polymerization reaction rate, as well as the eventual chain transfer to the side substituents of the pyranosyl groups of chitosan. A combined analysis of the modified membranes chemistry by proton nuclear magnetic resonance ((1)H-NMR), Fourier transform spectroscopy with attenuated total reflection (FTIR-ATR) and X-ray photoelectron spectroscopy (XPS) showed that it was possible to control the chitosan modification yield and depth in the solvent composition range between 75% and 100% of isopropanol. Plasma treatment was also applied to the original chitosan membranes in order to improve cell adhesion and proliferation. Chitosan membranes, which had been previously subjected to oxygen plasma treatment, were then modified by means of the previously described methodology. A human fetal lung fibroblast cell line was cultured until confluence on the plasma-treated thermo-responsive chitosan membranes and cell sheets were harvested lowering the temperature.

  14. DAP12 deficiency in liver allografts results in enhanced donor DC migration, augmented effector T cell responses and abrogation of transplant tolerance.

    Science.gov (United States)

    Yoshida, O; Kimura, S; Dou, L; Matta, B M; Yokota, S; Ross, M A; Geller, D A; Thomson, A W

    2014-08-01

    Liver interstitial dendritic cells (DC) have been implicated in immune regulation and tolerance induction. We found that the transmembrane immuno-adaptor DNAX-activating protein of 12 kDa (DAP12) negatively regulated conventional liver myeloid (m) DC maturation and their in vivo migratory and T cell allostimulatory ability. Livers were transplanted from C57BL/6(H2(b) ) (B6) WT or DAP12(-/-) mice into WT C3H (H2(k) ) recipients. Donor mDC (H2-K(b+) CD11c(+) ) were quantified in spleens by flow cytometry. Anti-donor T cell reactivity was evaluated by ex vivo carboxyfluorescein diacetate succinimidyl ester-mixed leukocyte reaction and delayed-type hypersensitivity responses, while T effector and regulatory T cells were determined by flow analysis. A threefold to fourfold increase in donor-derived DC was detected in spleens of DAP12(-/-) liver recipients compared with those given WT grafts. Moreover, pro-inflammatory cytokine gene expression in the graft, interferon gamma (IFNγ) production by graft-infiltrating CD8(+) T cells and systemic levels of IFNγ were all elevated significantly in DAP12(-/-) liver recipients. DAP12(-/-) grafts also exhibited reduced incidences of CD4(+) Foxp3(+) cells and enhanced CD8(+) T cell IFNγ secretion in response to donor antigen challenge. Unlike WT grafts, DAP12(-/-) livers failed to induce tolerance and were rejected acutely. Thus, DAP12 expression in liver grafts regulates donor mDC migration to host lymphoid tissue, alloreactive T cell responses and transplant tolerance.

  15. The Fetal Allograft Revisited: Does the Study of an Ancient Invertebrate Species Shed Light on the Role of Natural Killer Cells at the Maternal-Fetal Interface?

    Directory of Open Access Journals (Sweden)

    Breton F. Barrier

    2008-07-01

    Full Text Available Human pregnancy poses a fundamental immunological problem because the placenta and fetus are genetically different from the host mother. Classical transplantation theory has not provided a plausible solution to this problem. Study of naturally occurring allogeneic chimeras in the colonial marine invertebrate, Botryllus schlosseri, has yielded fresh insight into the primitive development of allorecognition, especially regarding the role of natural killer (NK cells. Uterine NK cells have a unique phenotype that appears to parallel aspects of the NK-like cells in the allorecognition system of B. schlosseri. Most notably, both cell types recognize and reject “missing self” and both are involved in the generation of a common vascular system between two individuals. Chimeric combination in B. schlosseri results in vascular fusion between two individual colonies; uterine NK cells appear essential to the establishment of adequate maternal-fetal circulation. Since human uterine NK cells appear to de-emphasize primary immunological function, it is proposed that they may share the same evolutionary roots as the B. schlosseri allorecognition system rather than a primary origin in immunity.

  16. Urine Metabolite Profiles Predictive of Human Kidney Allograft Status.

    Science.gov (United States)

    Suhre, Karsten; Schwartz, Joseph E; Sharma, Vijay K; Chen, Qiuying; Lee, John R; Muthukumar, Thangamani; Dadhania, Darshana M; Ding, Ruchuang; Ikle, David N; Bridges, Nancy D; Williams, Nikki M; Kastenmüller, Gabi; Karoly, Edward D; Mohney, Robert P; Abecassis, Michael; Friedewald, John; Knechtle, Stuart J; Becker, Yolanda T; Samstein, Benjamin; Shaked, Abraham; Gross, Steven S; Suthanthiran, Manikkam

    2016-02-01

    Noninvasive diagnosis and prognostication of acute cellular rejection in the kidney allograft may help realize the full benefits of kidney transplantation. To investigate whether urine metabolites predict kidney allograft status, we determined levels of 749 metabolites in 1516 urine samples from 241 kidney graft recipients enrolled in the prospective multicenter Clinical Trials in Organ Transplantation-04 study. A metabolite signature of the ratio of 3-sialyllactose to xanthosine in biopsy specimen-matched urine supernatants best discriminated acute cellular rejection biopsy specimens from specimens without rejection. For clinical application, we developed a high-throughput mass spectrometry-based assay that enabled absolute and rapid quantification of the 3-sialyllactose-to-xanthosine ratio in urine samples. A composite signature of ratios of 3-sialyllactose to xanthosine and quinolinate to X-16397 and our previously reported urinary cell mRNA signature of 18S ribosomal RNA, CD3ε mRNA, and interferon-inducible protein-10 mRNA outperformed the metabolite signatures and the mRNA signature. The area under the receiver operating characteristics curve for the composite metabolite-mRNA signature was 0.93, and the signature was diagnostic of acute cellular rejection with a specificity of 84% and a sensitivity of 90%. The composite signature, developed using solely biopsy specimen-matched urine samples, predicted future acute cellular rejection when applied to pristine samples taken days to weeks before biopsy. We conclude that metabolite profiling of urine offers a noninvasive means of diagnosing and prognosticating acute cellular rejection in the human kidney allograft, and that the combined metabolite and mRNA signature is diagnostic and prognostic of acute cellular rejection with very high accuracy.

  17. Silicon-on ceramic process. Silicon sheet growth and device development for the large-area silicon sheet and cell development tasks of the low-cost solar array project. Quarterly report No. 12, April 2, 1979-June 29, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, P.W.; Zook, J.D.; Heaps, J.D.; Grung, B.L.; Koepke, B.; Schuldt, S.B.

    1979-07-31

    The objective of this research program is to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon. We plan to do this by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. During the quarter, significant progress was demonstrated in several areas: (1) a 10-cm/sup 2/ cell having 9.9 percent conversion efficiency (AM1, AR) was fabricated; (2) the Honeywall-sponsored SCIM coating development succeeded in producing a 225-cm/sup 2/ layer of sheet silicon (18 inches x 2 inches); and (3) 100 ..mu..m-thick coatings at pull speed of 0.15 cm/sec wer$obta9ned, although apoproximately 50 percent of the layer exhibited dendritic growth. Other results and accomplishments during the quarter are reported in detail. (WHK)

  18. Zinc finger protein A20 protects rats against chronic liver allograft dysfunction

    Institute of Scientific and Technical Information of China (English)

    Jie Yang; Ming-Qing Xu; Lu-Nan Yan; Xiao-Bo Chen; Jiao Liu

    2012-01-01

    AIM:To investigate the effect of zinc finger protein A20 on chronic liver allograft dysfunction in rats.METHODS:Allogeneic liver transplantation from DA rats to Lewis rats was performed.Chronic liver allograft dysfunction was induced in the rats by administering low-dose tacrolimus at postoperative day (POD) 5.Hepatic overexpression of A20 was achieved by recombinant adenovirus (rAd.)-mediated gene transfer administered intravenously every 10 d starting from POD 10.The recipient rats were injected with physiological saline,rAdEasy-A20 (1 x 109 pfu/30 g weight) or rAdEasy (1 x 109 pfu/30 g weight) every 10 d through the tail vein for 3 mo starting from POD 10.Liver tissue samples were harvested on POD 30 and POD 60.RESULTS:Liver-transplanted rats treated with only tacrolimus showed chronic allograft dysfunction with severe hepatic fibrosis.A20 overexpression ameliorated the effects on liver function,attenuated liver allograft fibrosis and prolonged the survival of the recipient rats.Treatment with A20 suppressed hepatic protein production of tumor growth factor (TGF)-β1,interleukin1β,caspase-8,CD40,CD40L,intercellular adhesion molecule-1,vascular cell adhesion molecule-1 and E-selectin.A20 treatment suppressed liver cell apoptosis and inhibited nuclear factor-κB activation of Kupffer cells (KCs),liver sinusoidal endothelial cells (LSECs)and hepatic stellate cells (HSCs),and it subsequently decreased cytokine mRNA expression in KCs and LSECs and reduced the production of TGF-β1 in HSCs.CONCLUSION:A20 might prevent chronic liver allograft dysfunction by re-establishing functional homeostasis of KCs,LSECs and HSCs.

  19. Fabrication of a carbon nanofiber sheet as a micro-porous layer for proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Qiongjuan; Wang, Jiong; Lu, Yonggen [College of Material Science and Engineering, Donghua University, Shanghai 201620 (China); Wang, Biao; Wang, Huaping [State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620 (China); College of Material Science and Engineering, Donghua University, Shanghai 201620 (China)

    2010-12-15

    A carbon nanofiber sheet (CNFS) has been prepared by electrospinning, stabilisation and subsequent carbonisation processes. Imaging with scanning electron microscope (SEM) indicates that the CNFS is formed by nonwoven nanofibers with diameters between 400 and 700 nm. The CNFS, with its three-dimensional pores, shows excellent electrical conductivity and hydrophobicity. In addition, it is found that the CNFS can be successfully applied as a micro-porous layer (MPL) in the cathode gas diffusion layer (GDL) of a proton exchange membrane fuel cell (PEMFC). The GDL with the CNFS as a MPL has higher gas permeability than a conventional GDL. Moreover, the resultant cathode GDL exhibits excellent fuel cell performance with a higher peak power density than that of a cathode GDL fabricated with a conventional MPL under the same test condition. (author)

  20. Ultrastructural basis of acute renal allograft rejection

    NARCIS (Netherlands)

    V.D. Vuzevski (Vojislav)

    1976-01-01

    textabstractAn attempt was made: I. to demonstrate the evolution and the time of onset of the ultrastructural morphological changes in the renal parenchyma and blood vessels, as well as the ultrastructural feature of the interstitial cellular infiltration in acute rejection of kidney allografts; 2.

  1. Renal Allograft in a Professional Boxer

    Directory of Open Access Journals (Sweden)

    Einollahi Behzad

    2008-01-01

    Full Text Available Significant health benefits result from regular physical activity for kidney transplant recipients. Nevertheless, some adverse effects also have been shown to be associated with highly intensive exercises. We report a kidney transplant professional boxer whose kidney allograft has remained in good health, despite his violent sport activities.

  2. Renal allograft rejection. Unusual scintigraphic findings

    Energy Technology Data Exchange (ETDEWEB)

    Desai, A.G.; Park, C.H.

    1986-11-01

    During sequential renal imagining for evaluation of clinically suspected rejection, focal areas of functioning renal tissue were seen in two cases of renal transplant in the midst of severe and irreversible renal allograft rejection. A probable explanation for this histopathologically confirmed and previously unreported finding is discussed.

  3. Acceleration of Regeneration of Large-Gap Peripheral Nerve Injuries Using Acellular Nerve Allografts Plus Amniotic Fluid Derived Stem Cells (AFS)

    Science.gov (United States)

    2014-09-01

    nerves are incorporated into other rat strains without immunologic disturbances according to the vendor (AxoGen). 15. SUBJECT TERMS 16. SECURITY...mm). The outcomes of these surgeries will be compared to those obtained with autograft nerve repairs that currently have the best outcomes for large...ANA construct with AFS cells (Group 2), or with an autograft (nerve segment is cut out, reversed, and sewn back in place)(Group 3). All surgeries

  4. Effect of Adipose Tissue-Derived Osteogenic and Endothelial Cells on Bone Allograft Osteogenesis and Vascularization in Critical-Sized Calvarial Defects

    Science.gov (United States)

    2012-05-10

    Tsai, C.Y., and Wei, F.C. Har nessing the potential of the free fibula osteoseptocutaneous flap in mandible reconstruction. Plast Reconstr Surg 125...REPORT NUMBER 9. SPONSORING/ MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12...Magner, M., Isner, J.M., and Asahara, T. Ischemia and cytokine induced mobilization of bone mar row derived endothelial progenitor cells for neovascular

  5. Sympathetic Innervation Induced in Engrafted Engineered Cardiomyocyte Sheets by Glial Cell Line Derived Neurotrophic Factor In Vivo

    Directory of Open Access Journals (Sweden)

    Xian-ming Fu

    2013-01-01

    Full Text Available The aim of myocardial tissue engineering is to repair or regenerate damaged myocardium with engineered cardiac tissue. However, this strategy has been hampered by lack of functional integration of grafts with native myocardium. Autonomic innervation may be crucial for grafts to function properly with host myocardium. In this study, we explored the feasibility of in vivo induction of autonomic innervation to engineered myocardial tissue using genetic modulation by adenovirus encoding glial cell line derived neurotrophic factor (GDNF. GFP-transgene (control group or GDNF overexpressing (GDNF group engineered cardiomyocyte sheets were transplanted on cryoinjured hearts in rats. Nerve fibers in the grafts were examined by immunohistochemistry at 1, 2, and 4 weeks postoperatively. Growth associated protein-43 positive growing nerves and tyrosine hydroxylase positive sympathetic nerves were first detected in the grafts at 2 weeks postoperatively in control group and 1 week in GDNF group. The densities of growing nerve and sympathetic nerve in grafts were significantly increased in GDNF group. No choline acetyltransferase immunopositive parasympathetic nerves were observed in grafts. In conclusion, sympathetic innervation could be effectively induced into engrafted engineered cardiomyocyte sheets using GDNF.

  6. Arthroscopic meniscal allograft transplantation without bone plugs.

    Science.gov (United States)

    Alentorn-Geli, Eduard; Seijas Vázquez, Roberto; García Balletbó, Montserrat; Álvarez Díaz, Pedro; Steinbacher, Gilbert; Cuscó Segarra, Xavier; Rius Vilarrubia, Marta; Cugat Bertomeu, Ramón

    2011-02-01

    Partial or total meniscectomy are common procedures performed at Orthopedic Surgery departments. Despite providing a great relief of pain, it has been related to early onset knee osteoarthritis. Meniscal allograft transplantation has been proposed as an alternative to meniscectomy. The purposes of this study were to describe an arthroscopic meniscal allograft transplantation without bone plugs technique and to report the preliminary results. All meniscal allograft transplantations performed between 2001 and 2006 were approached for eligibility, and a total of 35 patients (involving 37 menisci) were finally engaged in the study. Patients were excluded if they had ipsilateral knee ligament reconstruction or cartilage repair surgery before meniscal transplantation or other knee surgeries after the meniscal transplantation. Scores on Lysholm, Subjective IKDC Form, and Visual Analogue Scale (VAS) scale for pain were obtained at a mean follow-up of 38.6 months and compared to pre-operative data. Data on chondral lesions were obtained during the arthroscopic procedure and through imaging (radiographs and MRI) studies pre-operatively. Two graft failures out of 59 transplants (3.4%) were found. Daily life accidents were responsible for all graft failures. Significant improvements for Lysholm, Subjective IKDC Form, and VAS for pain scores following the meniscal allograft transplantation were found (P lesion, there was no significant interactions for Lysholm (n.s.), Subjective IKDC Form (n.s.), and VAS for pain scores (n.s.). This study demonstrated that an arthroscopic meniscal allograft transplantation without bone plugs improved knee function and symptoms after a total meniscectomy. Improvements were observed independently of the degree of chondral lesion.

  7. Dependence of lattice strain relaxation, absorbance, and sheet resistance on thickness in textured ZnO@B transparent conductive oxide for thin-film solar cell applications

    Directory of Open Access Journals (Sweden)

    Kuang-Yang Kou

    2016-01-01

    Full Text Available The interplay of surface texture, strain relaxation, absorbance, grain size, and sheet resistance in textured, boron-doped ZnO (ZnO@B, transparent conductive oxide (TCO materials of different thicknesses used for thin film, solar cell applications is investigated. The residual strain induced by the lattice mismatch and the difference in the thermal expansion coefficient for thicker ZnO@B is relaxed, leading to an increased surface texture, stronger absorbance, larger grain size, and lower sheet resistance. These experimental results reveal the optical and material characteristics of the TCO layer, which could be useful for enhancing the performance of solar cells through an optimized TCO layer.

  8. Investigation of solar cells fabricated on low-cost silicon sheet materials using 1 MeV electron irradiation

    Science.gov (United States)

    Kachare, A. H.; Hyland, S. L.; Garlick, G. F. J.

    1981-01-01

    The use of high energy electron irradiation is investigated as a controlled means to study in more detail the junction depletion layer processes of solar cells made on various low-cost silicon sheet materials. Results show that solar cells made on Czochralski grown silicon exhibit enhancement of spectral response in the shorter wavelength region when irradiated with high energy electrons. The base region damage can be reduced by subsequent annealing at 450 C which restores the degraded longer wavelength response, although the shorter wavelength enhancement persists. The second diode component of the cell dark forward bias current is also reduced by electron irradiation, while thermal annealing at 450 C without electron irradiation can also produce these same effects. Electron irradiation produces small changes in the shorter wavelength spectral responses and junction improvements in solar cells made on WEB, EFG, and HEM silicon. It is concluded that these beneficial effects on cell characteristics are due to the reduction of oxygen associated deep level recombination centers in the N(+) diffused layer and in the junction.

  9. The Effects of Bio-Lubricating Molecules on Flexor Tendon Reconstruction in A Canine Allograft Model In Vivo

    Science.gov (United States)

    Zhao, Chunfeng; Wei, Zhuang; Kirk, Ramona L.; Thoreson, Andrew R.; Jay, Gregory D.; Moran, Steven L.; An, Kai-Nan; Amadio, Peter C.

    2014-01-01

    Background Using allograft is an attractive alternative for flexor tendon reconstruction because of the lack of donor morbidity, and better matching to the intrasynovial environment. The purpose of this study was to use biolubricant molecules to modify the graft surface to decrease adhesions and improve digit function. Methods 28 flexor digitorum profundus (FDP) tendons from the 2nd and 5th digits of 14 dogs were first lacerated and repaired to create a model with repair failure and scar digit for tendon reconstruction. Six weeks after the initial surgery, the tendons were reconstructed with FDP allograft tendons obtained from canine cadavers. One graft tendon in each dog was treated with saline as a control and the other was treated with gelatin, carbodiimide derivatized, hyaluronic acid and lubricin (cd-HA-Lubricin). Six weeks postoperatively, digit function, graft mechanics, and biology were analyzed. Results Allograft tendons treated with cd-HA-Lubricin had decreased adhesions at the proximal tendon/graft repair and within flexor sheath, improved digit function, and increased graft gliding ability. The treatment also reduced the strength at the distal tendon to bone repair, but the distal attachment rupture rate was similar for both graft types. Histology showed that viable cells migrated to the allograft, but these were limited to the tendon surface. Conclusion cd-HA-Lubricin treatment of tendon allograft improves digit functional outcomes after flexor tendon reconstruction. However, delayed bone-tendon healing should be a caution. Furthermore, the cell infiltration into the allograft tendons substance should be a target for future studies, to shorten the allograft self-regeneration period. PMID:24445876

  10. Decreased humoral antibody episodes of acute renal allograft rejection in recipients expressing the HLA-DQβ1*0202 allele.

    Science.gov (United States)

    Mannam, Venkat K R; Santos, Mark; Lewis, Robert E; Cruse, Julius M

    2012-10-01

    The present investigation was designed to show the effect of human leukocyte antigen (HLA) class II molecular allelic specificities in the recipient on the induction of humoral antibody rejection, identified by C4d peritubular capillary staining, as well as specific antibody identified by Luminex technology. Major histocompatibility complex (MHC) class II molecules are expressed on dendritic cells, macrophages, and B lymphocytes and they present antigenic peptides to CD4 positive T lymphocytes. Human renal peritubular and glomerular capillaries express class II MHC molecules upon activation. Expression of class II molecules on renal microvascular endothelial cells exposes them to possible interaction with specific circulating antibodies. We hypothesize that HLA-DQβ1*0202 expression in recipients decreases the likelihood of antibody-mediated renal allograft rejection. We found that 80% (=25) of DQ2 positive haplotype recipients failed to induce humoral antibody renal allograft rejection and 20% (n=25) of DQ2 positive haplotype recipients induced humoral antibody renal allograft rejection (p=0.008). By contrast, 48% (n=46) of DQ2 negative haplotype recipients failed to induce a humoral antibody component of renal allograft rejection and 52% (n=46) of DQ2 negative haplotype recipients induced humoral antibody-mediated renal allograft rejection. Our results suggest that recipients who express the DQβ1*0202 allele are less likely to induce a humoral antibody component of acute renal allograft rejection than are those expressing DQ1, DQ3, or DQ4 alleles. DQβ1*0202 allele expression in recipients could possibly be protective against acute humoral allograft rejection and might serve as a future criterion in recipient selection and in appropriate therapy for acute renal rejection episodes.

  11. Silicon-on Ceramic Process: Silicon Sheet Growth and Device Development for the Large-area Silicon Sheet and Cell Development Tasks of the Low-cost Solar Array Project

    Science.gov (United States)

    Chapman, P. W.; Zook, J. D.; Heaps, J. D.; Grung, B. L.; Koepke, B.; Schuldt, S. B.

    1979-01-01

    The technical and economic feasibility of producing solar cell-quality silicon was investigated. This was done by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. Significant progress in the following areas was demonstrated: (1) fabricating a 10 sq cm cell having 9.9 percent conversion efficiency; (2) producing a 225 sq cm layer of sheet silicon; and (3) obtaining 100 microns thick coatings at pull speed of 0.15 cm/sec, although approximately 50 percent of the layer exhibited dendritic growth.

  12. Lipidomics comparing DCD and DBD liver allografts uncovers lysophospholipids elevated in recipients undergoing early allograft dysfunction.

    Science.gov (United States)

    Xu, Jin; Casas-Ferreira, Ana M; Ma, Yun; Sen, Arundhuti; Kim, Min; Proitsi, Petroula; Shkodra, Maltina; Tena, Maria; Srinivasan, Parthi; Heaton, Nigel; Jassem, Wayel; Legido-Quigley, Cristina

    2015-12-04

    Finding specific biomarkers of liver damage in clinical evaluations could increase the pool of available organs for transplantation. Lipids are key regulators in cell necrosis and hence this study hypothesised that lipid levels could be altered in organs suffering severe ischemia. Matched pre- and post-transplant biopsies from donation after circulatory death (DCD, n = 36, mean warm ischemia time = 2 min) and donation after brain death (DBD, n = 76, warm ischemia time = none) were collected. Lipidomic discovery and multivariate analysis (MVA) were applied. Afterwards, univariate analysis and clinical associations were conducted for selected lipids differentiating between these two groups. MVA grouped DCD vs. DBD (p = 6.20 × 10(-12)) and 12 phospholipids were selected for intact lipid measurements. Two lysophosphatidylcholines, LysoPC (16:0) and LysoPC (18:0), showed higher levels in DCD at pre-transplantation (q < 0.01). Lysophosphatidylcholines were associated with aspartate aminotransferase (AST) 14-day post-transplantation (q < 0.05) and were more abundant in recipients undergoing early allograft dysfunction (EAD) (p < 0.05). A receiver-operating characteristics (ROC) curve combining both lipid levels predicted EAD with 82% accuracy. These findings suggest that LysoPC (16:0) and LysoPC (18:0) might have a role in signalling liver tissue damage due to warm ischemia before transplantation.

  13. Activated Regulatory T Cells Expressing CD4(+)CD25(high)CD45RO(+)CD62L(+) Biomarkers Could Be a Risk Factor in Liver Allograft Rejection.

    Science.gov (United States)

    Boix, F; Millan, O; San Segundo, D; Mancebo, E; Miras, M; Rimola, A; Fábrega, E; Allende, L; Minguela, A; Paz-Artal, E; López-Hoyos, M; Brunet, M; Muro, M

    2015-10-01

    Activated regulatory T cells (aTregs) are nowadays a hot topic in organ transplantation to establish their role during acute rejection (AR) episodes. The aim of this multi-center study was to monitor the frequency of aTregs within the first year after transplantation in a cohort of first-time liver transplant recipients enrolled from 2010 to 2012. aTregs frequency was analyzed by means of flow cytometry. Patients who had AR showed higher levels of aTregs during first year after transplantation in comparison with patients who did not have higher levels. High levels of aTregs in liver recipients might be used as a biomarker of AR; however, further studies must be done to address the potential role of aTregs as biomarkers of AR in liver transplantation.

  14. Experimental Study on Allograft of Rabbit Adipose-derived Stem Cells Transplantation%兔异体脂肪干细胞移植的实验研究

    Institute of Scientific and Technical Information of China (English)

    杨涛; 杨勇; 刘斌; 李龙; 令狐大科; 刘彦普

    2013-01-01

    Objective: To establish an animal model for the injectable allo-transplantation fat tissue transplantation and to investigate the morphological and immunologic changes of rejection after ear allo-transplantation in rabbit. Methods: 30 healthy New Zealand white rabbits were divided into three groups randomly. The autologous adipose granule (AG) were implanted in the ears of the rabbits as the experiment group A(N=6). The autologous adipose granule (AG) combined with platelet-rich fibrin(PRF) were implanted in ears as the experiment group B(N=6). The autologous adipose granule(AG) combined with autologous adipose-derived stem cells(ADSCs)were implanted in ears as the experiment group C(N=6). The autologous adipose granule(AG) combined with platelet-rich fibrin(PRF) and autologous adipose-derived stem cells(ADSCs) were implanted in the ears were the control group D(N=6). The autologous adipose granule (AG) combined with platelet-rich fibrin (PRF) and allo-transplantation adipose-derived stem cells (ADSCs) were implanted in the ears were the control group E(N=6).At month 1,3 and 6 after transplantation, the level of CD4/CD8 in lymph cells and IL-2, IL-4 in plasma of the rabbits were examined. Results: At 1,3and 6 months after surgery, the differences of the two groups D, E and group A, B, C were statistical significant (P 0.05). Conclusion: The autologous adipose granule (AG) combined with platelet-rich fibrin (PRF) and autologous adipose-derived stem cells (ADSCs) can improve the survival rate of transplanted fat tissue and provide experimental basis for clinical fat allo-transplantation.%目的:建立一种可注射异体脂肪移植模型,观察兔异体脂肪干细胞(adipose-derived stem cells,ADSCs)复合自体脂肪颗粒(adipose granule,AG)和富血小板纤维蛋白(platelet-rich fibrin,PRF)移植后的形态学和免疫学的变化,为临床异体脂肪干细胞移植提供一种实验依据.方法:取30只健康新西兰家兔,随机分成5组:A组,(N=6),

  15. 5D imaging via light sheet microscopy reveals cell dynamics during the eye-antenna disc primordium formation in Drosophila

    Science.gov (United States)

    Huang, Yu Shan; Ku, Hui Yu; Tsai, Yun Chi; Chang, Chin Hao; Pao, Sih Hua; Sun, Y. Henry; Chiou, Arthur

    2017-03-01

    5D images of engrailed (en) and eye gone (eyg) gene expressions during the course of the eye-antenna disc primordium (EADP) formation of Drosophila embryos from embryonic stages 13 through 16 were recorded via light sheet microscopy and analyzed to reveal the cell dynamics involved in the development of the EADP. Detailed analysis of the time-lapsed images revealed the process of EADP formation and its invagination trajectory, which involved an inversion of the EADP anterior-posterior axis relative to the body. Furthermore, analysis of the en-expression pattern in the EADP provided strong evidence that the EADP is derived from one of the en-expressing head segments.

  16. Effects of Sheet Resistance on mc-Si Selective Emitter Solar Cells Using Laser Opening and One-Step Diffusion

    Directory of Open Access Journals (Sweden)

    Sheng-Shih Wang

    2015-01-01

    Full Text Available In order to simplify process procedure and improve conversion efficiency (η, we present new steps of laser opening and one-step POCl3 diffusion to fabricate selective emitter (SE solar cells, in which heavily doped regions (HDR and lightly doped regions (LDR were formed simultaneously. For HDR, we divided six cells into two groups for POCl3 diffusion with sheet resistance (RS of 40 Ω/sq (for group A and 50 Ω/sq (for group B. The dry oxidation duration at a temperature of 850°C was 18, 25, and 35 min for the 3 different cells in each group. This created six SE samples with different RS pairings for the HDR and LDR. The optimal cell (sample SE2 with RS values of 40/81 Ω/Sq in HDR/LDR showed the best η of 16.20%, open circuit voltage (VOC of 612.52 mV, and fill factor (FF of 75.83%. The improvement ratios are 1.57% for η and 14.32% for external quantum efficiency (EQE as compared with those of the two-step diffusion process of our previous study. Moreover, the one-step laser opening process and omitting the step of removing the damage caused by laser ablation especially reduce chemistry pollution, thus showing ecofriendly process for use in industrial-scale production.

  17. Performance of a proton exchange membrane fuel cell stack with thermally conductive pyrolytic graphite sheets for thermal management

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Chih-Yung; Lin, Yu-Sheng; Lu, Chien-Heng [Department of Aeronautics and Astronautics, National Cheng-Kung University, Tainan 70101 (China)

    2009-04-15

    This work experimentally investigates the effects of the pyrolytic graphite sheets (PGS) on the performance and thermal management of a proton exchange membrane fuel cell (PEMFC) stack. These PGS with the features of light weight and high thermal conductivity serve as heat spreaders in the fuel cell stack for the first time to reduce the volume and weight of cooling systems, and homogenizes the temperature in the reaction areas. A PEMFC stack with an active area of 100 cm{sup 2} and 10 cells in series is constructed and used in this research. Five PGS of thickness 0.1 mm are cut into the shape of flow channels and bound to the central five cathode gas channel plates. Four thermocouples are embedded on the cathode gas channel plates to estimate the temperature variation in the stack. It is shown that the maximum power of the stack increase more than 15% with PGS attached. PGS improve the stack performance and alleviate the flooding problem at low cathode flow rates significantly. Results of this study demonstrate the feasibility of application of PGS to the thermal management of a small-to-medium-sized fuel cell stack. (author)

  18. Award-Winning Etching Process Cuts Solar Cell Costs (Revised) (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2011-05-01

    The NREL "black silicon" nanocatalytic wet-chemical etch is an inexpensive, one-step method to minimize reflections from crystalline silicon solar cells. The technology enables high-efficiency solar cells without the use of expensive antireflection coatings.

  19. Optimized total body irradiation for induction of renal allograft tolerance through mixed chimerism in cynomolgus monkeys

    Energy Technology Data Exchange (ETDEWEB)

    Kimikawa, Masaaki; Kawai, Tatsuo; Ota, Kazuo [Tokyo Women`s Medical Coll. (Japan)

    1996-12-01

    We previously demonstrated that a nonmyeloablative preparative regimen can induce mixed chimerism and renal allograft tolerance between MHC-disparate non-human primates. The basic regimen includes anti-thymocyte globulin (ATG), total body irradiation (TBI, 300 cGy), thymic irradiation (TI, 700 cGy), splenectomy, donor bone marrow (DBM) infusion, and posttransplant cyclosporine therapy (CYA, discontinued after 4 weeks). To evaluate the importance and to minimize the toxicity of irradiation, kidney allografts were transplanted with various manipulations of the irradiation protocol. Monkeys treated with the basic protocol without TBI and TI did not develop chimerism or long-term allograft survival. In monkeys treated with the full protocol, all six monkeys treated with two fractionated dose of 150 cGy developed chimerism and five monkeys appeared tolerant. In contrast, only two of the four monkeys treated with fractionated doses of 125 cGy developed chimerism and only one monkey survived long term. The degree of lymphocyte depletion in all recipients was proportional to the TBI dose. The fractionated TBI regimen of 150 cGy appears to be the most consistently effective regimen for establishing donor bone marrow cell engraftment and allograft tolerance. (author)

  20. Effect of the hydrophobic basal layer of thermoresponsive block co-polymer brushes on thermally-induced cell sheet harvest.

    Science.gov (United States)

    Matsuzaka, Naoki; Takahashi, Hironobu; Nakayama, Masamichi; Kikuchi, Akihiko; Okano, Teruo

    2012-01-01

    Thermoresponsive poly(benzyl methacrylate)-b-poly(N-isopropylacrylamide) (PBzMA-b-PIPAAm) block co-polymer brush surfaces were prepared by surface-initiated two-step reversible addition-fragmentation chain transfer radical (RAFT) polymerization. PBzMA brushes were fabricated on azoinitiator-immobilized glass substrates in the presence of dithiobenzoate (DTB) compound as a RAFT agent. The amount of grafted polymer was regulated by initial monomer concentrations. The second thermoresponsive blocks were added to the RAFT-related DTB groups located at PBzMA termini through the propagation of PIPAAm chains, resulting in formation of PBzMA-b-PIPAAm brushes. Surface characteristics of the block co-polymer brushes and its influence on thermally regulated cellular behavior were investigated using bovine carotid artery endothelial cells (BAECs), compared with PIPAAm brush surfaces. Cell adhesion/detachment behavior on thermoresponsive polymer brush surfaces significantly depended on their individual polymer architectures and chemical compositions of grafted polymers. Low-temperature treatment at 20°C, below the phase-transition temperature of PIPAAm, induced the spontaneous detachment of adhering cells from the PBzMA-b-PIPAAm brush surfaces with a higher rate than that from PIPAAm brush surfaces. In addition, the cell-repellent effect of the hydrophobic basal layer successfully accelerated for harvesting BAEC sheets from the block co-polymer brush surfaces. Unique features of thermoresponsive block co-polymer brush architectures can be applied to control cell-adhesion strength for enhancing cell adhesion or accelerating cell detachment.

  1. Evaluation of kidney allograft status using novel ultrasonic technologies

    Directory of Open Access Journals (Sweden)

    Cheng Yang

    2015-07-01

    Full Text Available Early diagnosis of kidney allograft injury contributes to proper decisions regarding treatment strategy and promotes the long-term survival of both the recipients and the allografts. Although biopsy remains the gold standard, non-invasive methods of kidney allograft evaluation are required for clinical practice. Recently, novel ultrasonic technologies have been applied in the evaluation and diagnosis of kidney allograft status, including tissue elasticity quantification using acoustic radiation force impulse (ARFI and contrast-enhanced ultrasonography (CEUS. In this review, we discuss current opinions on the application of ARFI and CEUS for evaluating kidney allograft function and their possible influencing factors, advantages and limitations. We also compare these two technologies with other non-invasive diagnostic methods, including nuclear medicine and radiology. While the role of novel non-invasive ultrasonic technologies in the assessment of kidney allografts requires further investigation, the use of such technologies remains highly promising.

  2. Focal segmental glomerulosclerosis recurrence in the renal allograft.

    Science.gov (United States)

    Leca, Nicolae

    2014-09-01

    Focal segmental glomerulosclerosis (FSGS) represents a common histologic pattern of glomerular injury associated with a multitude of disease mechanisms. The etiology of FSGS is often classified into primary (idiopathic) and secondary forms in response to genetic abnormalities, infections, toxins, and systemic disorders that lead to adaptive changes, glomerular hyperfiltration, and proteinuria. Our understanding of the pathogenic mechanisms responsible for FSGS was substantially enhanced in recent years because of major advances in the cell biology of the podocyte and parietal epithelial cell. Recurrence of FSGS occurs mainly in its primary form and is only rarely described in secondary forms. The re-enactment of pathologic mechanisms of FSGS as recurrent disease after kidney transplantation represents a biologic experiment that can provide unique insight. Nonetheless, recurrent FSGS remains a notable clinical problem that correlates with poorer renal allograft outcomes. This is the focus of this particular review, concentrating on the most recent developments.

  3. Long-term outcome of free fibula osteocutaneous flap and massive allograft in the reconstruction of long bone defect.

    Science.gov (United States)

    Halim, Ahmad Sukari; Chai, Siew Cheng; Wan Ismail, Wan Faisham; Wan Azman, Wan Sulaiman; Mat Saad, Arman Zaharil; Wan, Zulmi

    2015-12-01

    Reconstruction of massive bone defects in bone tumors with allografts has been shown to have significant complications including infection, delayed or nonunion of allograft, and allograft fracture. Resection compounded with soft tissue defects requires skin coverage. A composite osteocutaneous free fibula offers an optimal solution where the allografts can be augmented mechanically and achieve biological incorporation. Following resection, the cutaneous component of the free osteocutaneous fibula flaps covers the massive soft tissue defect. In this retrospective study, the long-term outcome of 12 patients, who underwent single-stage limb reconstruction with massive allograft and free fibula osteocutaneous flaps instead of free fibula osteal flaps only, was evaluated. This study included 12 consecutive patients who had primary bone tumors and had follow-up for a minimum of 24 months. The mean age at the time of surgery was 19.8 years. A total of eight patients had primary malignant bone tumors (five osteosarcomas, two chondrosarcomas and one synovial sarcoma), and four patients had benign bone tumors (two giant-cell tumors, one aneurysmal bone cyst, and one neurofibromatosis). The mean follow-up for the 12 patients was 63 months (range 24-124 months). Out of the 10 patients, nine underwent lower-limb reconstruction and ambulated with partial weight bearing and full weight bearing at an average of 4.2 months and 8.2 months, respectively. In conclusion, augmentation of a massive allograft with free fibula osteocutaneous flap is an excellent alternative for reducing the long-term complication of massive allograft and concurrently addresses the soft tissue coverage.

  4. Silicon-on-ceramic process: silicon sheet growth and device development for the Large-Area Silicon Sheet and Cell Development Tasks of the Low-Cost Solar Array Project. Quarterly report No. 11, January 1-March 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, P.W.; Zook, J.D.; Heaps, J.D.; Grung, B.L.; Koepke, B.; Schuldt, S.B.

    1979-04-30

    The purpose of the research program is to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating inexpensive ceramic substrates with a thin layer of polycrystalline silicon. The coating methods to be developed are directed toward a minimum-cost process for producing solar cells with a terrestrial conversion efficiency of 12 percent or greater. By applying a graphite coating to one face of a ceramic substrate, molten silicon can be caused to wet only that graphite-coated face and produce uniform thin layers of large-grain polycrystalline silicon; thus, only a minimal quantity of silicon is consumed. A dip-coating method for putting silicon on ceramic (SOC) has been shown to produce solar-cell-quality sheet silicon. This method and a continuous coating process also being investigated have excellent scale-up potential which offers an outstanding, cost-effective way to manufacture large-area solar cells. Results and accomplishments are described.

  5. Preparation and characterization of mono-sheet bipolar membranes by pre-irradiation grafting method for fuel cell applications

    Science.gov (United States)

    Guan, Yingjie; Fang, Jun; Fu, Tao; Zhou, Huili; Wang, Xin; Deng, Zixiang; Zhao, Jinbao

    2016-09-01

    A new method for the preparation of the mono-sheet bipolar membrane applied to fuel cells was developed based on the pre-irradiation grafting technology. A series of bipolar membranes were successfully prepared by simultaneously grafting of styrene onto one side of the poly(ethylene-co-tetrafluoroethylene) base film and 1-vinylimidazole onto the opposite side, followed by the sulfonation and alkylation, respectively. The chemical structures and microstructures of the prepared membranes were investigated by ATR-FTIR and SEM-EDS. The TGA measurements demonstrated the prepared bipolar membranes have reasonable thermal stability. The ion exchange capacity, water uptake and ionic conductivity of the membranes were also characterized. The H2/O2 single fuel cells using these membranes were evaluated and revealed a maximum power density of 107 mW cm-2 at 35 °C with unhumidified hydrogen and oxygen. The preliminary performances suggested the great prospect of these membranes in application of bipolar membrane fuel cells.

  6. CD28/B7-MEDIATED COSTIMULATION IS REQUIREDFOR PARATHYROID GLAND ALLOGRAFT REJECTION IN RATS

    Institute of Scientific and Technical Information of China (English)

    肖毅; 朱预; 陈力真; 王树蕙; 何小东

    1999-01-01

    The activation of T cells to differentiate and to proliferate is an essential step in the immune response to antigen, especially in cell-mediated acute allograft rejection. Besides the interaction of CD3/TCR complex with Ag/MHC complex presented on antigen-presenting cells, a complete T-cell activation and proliferation requires a second costimulatory signal. The interaction of CD28/CTLA-4 and B7 is a major costim-ulatory pathway for T Cell activation. Inhibition of this pathway results in development of antigen-specific unresponsiveness and clonal anergy. In present study, the biologic function of anti-CD28 monoclonsl anti-body and its Fab fragment were investigated in vitro and in viro. The results indicate that mAbCD28 and its Fab fragments could promote the functional recovery of allografts and prolong the graft suvival, but could not reverse the acute rejection or induce transplantation tolerance in the rat PTG allograft model. We also found that peripheral TNF-α level and NK-cell activity were suppressed in the presence of mAbCD28 and its Yab fragments for s relatively long time after PTG transplantation.

  7. Silicon sheet with molecular beam epitaxy for high efficiency solar cells

    Science.gov (United States)

    Allen, F. G.

    1983-01-01

    The capabilities of the new technique of Molecular Beam Epitaxy (MBE) are applied to the growth of high efficiency silicon solar cells. Because MBE can provide well controlled doping profiles of any desired arbitrary design, including doping profiles of such complexity as built-in surface fields or tandem junction cells, it would appear to be the ideal method for development of high efficiency solar cells. It was proposed that UCLA grow and characterize silicon films and p-n junctions of MBE to determine whether the high crystal quality needed for solar cells could be achieved.

  8. Cytomegalovirus and chronic allograft rejection in liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Liang-Hui Gao; Shu-Sen Zheng

    2004-01-01

    Cytomegalovirus (CMV) remains one of the most frequent viral infections and the most common cause of death after liver transplantation (LT). Chronic allograft liver rejection remains the major obstacle to long-term allograft survival and CMV infection is one of the suggested risk factors for chronic allograft rejection. The precise relationship between cytomegalovirus and chronic rejection remains uncertain.This review addresses the morbidity of cytomegalovirus infection and the risk factors associated with it, the relationship between cytomegalovirus and chronic allograft liver rejection and the potential mechanisms of it.

  9. Late de novo minimal change disease in a renal allograft

    Directory of Open Access Journals (Sweden)

    Madhan Krishan

    2009-01-01

    Full Text Available Among the causes of the nephrotic syndrome in renal allografts, minimal change disease is a rarity with only few cases described in the medical literature. Most cases described have occurred early in the post-transplant course. There is no established treatment for the condition but prognosis is favorable. We describe a case of minimal change disease that developed 8 years after a successful transplantation of a renal allograft in a middle-aged woman. The nephrotic syndrome was accompanied by deterioration of allograft function. Treatment with mycophenolate mofetil was successful in inducing remission and stabilizing allograft function.

  10. Late de novo minimal change disease in a renal allograft.

    Science.gov (United States)

    Madhan, Krishan K; Temple-Camp, Cynric R E

    2009-03-01

    Among the causes of the nephrotic syndrome in renal allografts, minimal change disease is a rarity with only few cases described in the medical literature. Most cases described have occurred early in the post-transplant course. There is no established treatment for the condition but prognosis is favorable. We describe a case of minimal change disease that developed 8 years after a successful transplantation of a renal allograft in a middle-aged woman. The nephrotic syndrome was accompanied by deterioration of allograft function. Treatment with mycophenolate mofetil was successful in inducing remission and stabilizing allograft function.

  11. Improving the osteogenesis of human bone marrow mesenchymal stem cell sheets by microRNA-21-loaded chitosan/hyaluronic acid nanoparticles via reverse transfection

    Directory of Open Access Journals (Sweden)

    Wang Z

    2016-05-01

    Full Text Available Zhongshan Wang,1 Guangsheng Wu,2,3 Mengying Wei,4 Qian Liu,1 Jian Zhou,1 Tian Qin,1 Xiaoke Feng,1 Huan Liu,1 Zhihong Feng,1 Yimin Zhao1 1State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Oral Diseases, Department of Prosthodontics, 2State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Periodontology, School of Stomatology, The Fourth Military Medical University, Xi’an, 3Qingdao First Sanatorium, Jinan Military Region, Qingdao, Shandong Province, 4Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi’an, People’s Republic of China Abstract: Cell sheet engineering has emerged as a novel approach to effectively deliver seeding cells for tissue regeneration, and developing human bone marrow mesenchymal stem cell (hBMMSC sheets with high osteogenic ability is a constant requirement from clinics for faster and higher-quality bone formation. In this work, we fabricated biocompatible and safe chitosan (CS/hyaluronic acid (HA nanoparticles (NPs to deliver microRNA-21 (miR-21, which has been proved to accelerate osteogenesis in hBMMSCs; then, the CS/HA/miR-21 NPs were cross-linked onto the surfaces of culture plates with 0.2% gel solution to fabricate miR-21-functionalized culture plates for reverse transfection. hBMMSC sheets were induced continuously for 14 days using a vitamin C-rich method on the miR-21-functionalized culture plates. For the characterization of CS/HA/miR-21 NPs, the particle size, zeta potential, surface morphology, and gel retardation were sequentially investigated. Then, the biological effects of hBMMSC sheets on the miR-21-functionalized culture plates were evaluated. The assay results demonstrated that the hBMMSC sheets could be successfully induced via the novel

  12. Urinary calprotectin and posttransplant renal allograft injury.

    Directory of Open Access Journals (Sweden)

    Martin Tepel

    Full Text Available OBJECTIVE: Current methods do not predict the acute renal allograft injury immediately after kidney transplantation. We evaluated the diagnostic performance of urinary calprotectin for predicting immediate posttransplant allograft injury. METHODS: In a multicenter, prospective-cohort study of 144 incipient renal transplant recipients, we postoperatively measured urinary calprotectin using an enzyme-linked immunosorbent assay and estimated glomerular filtration rate (eGFR after 4 weeks, 6 months, and 12 months. RESULTS: We observed a significant inverse association of urinary calprotectin concentrations and eGFR 4 weeks after transplantation (Spearman r =  -0.33; P<0.001. Compared to the lowest quartile, patients in the highest quartile of urinary calprotectin had an increased risk for an eGFR less than 30 mL/min/1.73 m(2 four weeks after transplantation (relative risk, 4.3; P<0.001; sensitivity, 0.92; 95% CI, 0.77 to 0.98; specificity, 0.48; 95% CI, 0.31 to 0.66. Higher urinary calprotectin concentrations predicted impaired kidney function 4 weeks after transplantation, as well as 6 months and 12 months after transplantation. When data were analyzed using the urinary calprotectin/creatinine-ratio similar results were obtained. Urinary calprotectin was superior to current use of absolute change of plasma creatinine to predict allograft function 12 months after transplantation. Urinary calprotectin predicted an increased risk both in transplants from living and deceased donors. Multivariate linear regression showed that higher urinary calprotectin concentrations and older donor age predicted lower eGFR four weeks, 6 months, and 12 months after transplantation. CONCLUSIONS: Urinary calprotectin is an early, noninvasive predictor of immediate renal allograft injury after kidney transplantation.

  13. Extensor mechanism allograft in total knee arthroplasty

    Science.gov (United States)

    Helito, Camilo Partezani; Gobbi, Riccardo Gomes; Tozi, Mateus Ramos; Félix, Alessandro Monterroso; Angelini, Fábio Janson; Pécora, José Ricardo

    2013-01-01

    Objective To analyze the experience with allograft transplantation of the extensor mechanism in total knee arthroplasty and compare results with the international experience. Methods We retrospectively evaluated three cases of extensor mechanism allograft after total knee arthroplasty performed in our hospital with the aid of one of the few tissue banks in Brazil and attempt to establish whether our experiences were similar to others reported in the world literature regarding patient indication, techniques, and outcomes. Results Two cases went well with the adopted procedure, and one case showed bad results and progressed to amputation. As shown in the literature, the adequate tension of the graft, appropriate tibial fixation and especially the adequate patient selection are the better predictors of good outcomes. Previous chronic infection can be an unfavorable predictor. Conclusion This surgical procedure has precise indication, albeit uncommon, either because of the rarity of the problem or because of the low availability of allografts, due to the scarcity of tissue banks in Brazil. Level of Evidence IV, Case Series. PMID:24453688

  14. Uremic escape of renal allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    van Schilfgaarde, R. (Rijksuniversiteit Leiden (Netherlands). Academisch Ziekenhuis); van Breda Vriesman, P.J.C. (Rijksuniversiteit Limburg Maastricht (Netherlands). Dept. of Immunopathology)

    1981-10-01

    It is demonstrated in rats that, in the presence of early postoperative severe but transient uremia, the survival of first set Brown-Norway (BN) renal allografts in Lewis (LEW) recipients is at least three times prolonged when compared to non-uremic controls. This phenomenon is called 'uremic escape of renal allograft rejection'. By means of lethal X-irradiation of donors of BN kidneys transplanted into transiently uremic and non-uremic LEW recipients, the presence of passenger lymphocyte immunocompetence is demonstrated to be obilgatory for this phenomenon to occur. As a result of mobile passenger lymphocyte immunocompetence, a graft-versus-host (GVH) reaction is elicited in the spleens of LEW recipients of BN kidneys which amplifies the host response. The splenomegaly observed in LEW recipients of BN kidneys is caused not only by this GVH reaction, which is shown to be exquisitely sensitive to even mild uremia. It is also contributed to by a proliferative response of the host against the graft (which latter response is equated with an in vivo equivalent of a unilateral mixed lymphocyte reaction (MLR)), since the reduction in spleen weights caused by abrogation of mobile passenger lymphocyte immunocompetence brought about by lethal donor X-irradiation is increased significantly by early postoperative severe but transient uremia. It is concluded that in uremic escape of renal allograft rejection both reactions are suppressed by uremia during the early post-operative period.

  15. RNA-seq Analysis of Clinical-Grade Osteochondral Allografts Reveals Activation of Early Response Genes

    Science.gov (United States)

    Lin, Yang; Lewallen, Eric A.; Camilleri, Emily T.; Bonin, Carolina A.; Jones, Dakota L.; Dudakovic, Amel; Galeano-Garces, Catalina; Wang, Wei; Karperien, Marcel J.; Larson, Annalise N.; Dahm, Diane L.; Stuart, Michael J.; Levy, Bruce A.; Smith, Jay; Ryssman, Daniel B.; Westendorf, Jennifer J.; Im, Hee-Jeong; van Wijnen, Andre J.; Riester, Scott M.; Krych, Aaron J.

    2016-01-01

    Preservation of osteochondral allografts used for transplantation is critical to ensure favorable outcomes for patients after surgical treatment of cartilage defects. To study the biological effects of protocols currently used for cartilage storage, we investigated differences in gene expression between stored allograft cartilage and fresh cartilage from living donors using high throughput molecular screening strategies. We applied next generation RNA sequencing (RNA-seq) and real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) to assess genome-wide differences in mRNA expression between stored allograft cartilage and fresh cartilage tissue from living donors. Gene ontology analysis was used to characterize biological pathways associated with differentially expressed genes. Our studies establish reduced levels of mRNAs encoding cartilage related extracellular matrix (ECM) proteins (i.e., COL1A1, COL2A1, COL10A1, ACAN, DCN, HAPLN1, TNC, and COMP) in stored cartilage. These changes occur concomitantly with increased expression of “early response genes” that encode transcription factors mediating stress/cytoprotective responses (i.e., EGR1, EGR2, EGR3, MYC, FOS, FOSB, FOSL1, FOSL2, JUN, JUNB, and JUND). The elevated expression of “early response genes” and reduced levels of ECM-related mRNAs in stored cartilage allografts suggests that tissue viability may be maintained by a cytoprotective program that reduces cell metabolic activity. These findings have potential implications for future studies focused on quality assessment and clinical optimization of osteochondral allografts used for cartilage transplantation. PMID:26909883

  16. Application of anti-CD103 immunotoxin for saving islet allograft in context of transplantation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lei; Gregg A. Hadley

    2010-01-01

    Background Previous studies using knockout mice document a key role for the integrin CD103 in promoting organ allograft rejection and graft-versus-host disease. However, a determination of whether blockade of the CD103 pathway represents a viable therapeutic strategy for intervention in these processes has proven problematic due to the lack of reagents that efficiently deplete CD103+ cells from wild type hosts. To circumvent this problem, in the present study, we invented an anti-CD103 immunotoxin (M290-SAP). We investigated whether M290-SAP has capacity to eliminate CD103-expressing cells in vivo and protect transplanted islets from destroying by host immune cells.Methods Flow cytometry was used to analyze the efficacy of M290-SAP in depleting CD103-expressing cells in vivo.Then using allogenic islet transplantation models as well as NOD mice with recent onset type 1 diabetes, the therapeutic efficacy of CD103-expressing cell depletion was addressed.Results M290-SAP dramatically reduces the frequency and absolute numbers of CD103-expressing leukocytes in peripheral lymphatic tissues of treated mice. Balb/c islets transplanted into streptozotocin-induced diabetic C57BL/6 mice under single M290-SAP treatment showed an indefinite survival time compared with untreated mice, M290-treated mice and IgG-SAP treated mice (mean survival time, >100 days vs. <20 days). C57BL/6 islets transplanted into hyperglycemic NOD mice under single M290-SAP treatment showed a pronounced delay in allograft rejection compared with untreated mice (mean survival time 12-13 days vs. <7 days). Immunological analysis of mice with long-term islet allograft survival revealed an obvious atrophy thymus and severe downregulation of alloimmunity of CD8 subpopulation response to allogenic stimulation.Conclusion Regardless of the underlying mechanisms, these data document that depletion of CD103-expressing cells represents a viable strategy for therapeutic intervention in islet allograft

  17. 体液性排斥反应患者移植物组织C4d沉积和浆细胞聚集性浸润初探%A retrospective analysis on the relationship between C4d deposition and infiltration of plasma-cell nodules in liver and renal allografts and their roles in humoral rejection

    Institute of Scientific and Technical Information of China (English)

    石炳毅; 许晓光; 蔡明; 宋继勇; 韩永

    2009-01-01

    Objective To detect the deposition of C4d and the infiltration of plasma cells in liver and renal allografts and to study the correlations among C4d deposition, plasma cells infiltration and humoral rejection.Methods Thirty-four liver biopsy specimens from 28 liver transplant patients and 43 tissues from excised renal allografts of rejections were stained with HE and analyzed by immunohistochemistry. Ten excised renal specimens from patients with other diseases rather than rejection and specimens from donor liver explants were collected as negative controls. Renal allograft rejection was classified with Banff 97. The expression of C4d and CD138 were detected and their relationship was analyzed.Results Histopathology showed that acute rejection occurred in 16 liver allografts, chronic humoral rejection in 9 and no rejection in 9. Liver biopsies before transplantation showed no Cd4 positive;9 (56.3%) cases in acute rejection group were detected C4d positive, 5(55.6%) cases in chronic rejection group, and 1(11.1%) case with stenosis of bile duct in no rejection group. Eleven tissue specimens from rejected allografts were detected CD138 positive and 8 were detected both C4d and CD138 positive. Among the 43 renal allografts specimens, 5 had hyperacute rejection, 9 acute rejection, and 29 chronic rejection;19(44.2%) were detected C4d positive, 24(55.8%) CD138 positive, and 10(23.3%) both positive. C4d and CD138 are related by the Spearman analysis in liver and renal allografts (r=0.364, P<0.05;r=0.5051, P<0.01). One case of C4d positive and no CD138 positive were detected in the negative controls.Conclusion C4d and CD138 are correlated, suggesting the plasma nodules infiltration in liver and renal allograft probably participate in humoral rejection through secreting antibodies locally.%目的 检测移植肝及肾组织中浆细胞的浸润和补体C4裂解产物C4d的沉积情况,分析浆细胞浸润、C4d沉积与体液性排斥反应的相关性.方法 25例肝移

  18. Silicon-on-ceramic coating process. Silicon sheet growth development for the Large-Area Silicon Sheet and Cell Development Tasks of the Low-Cost Silicon Solar Array Project. Quarterly report No. 8, December 28, 1977--March 28, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, P.W. Zook, J.D.; Heaps, J D; Maclolek, R B; Koepke, B; Butter, C D; Schult, S B

    1978-04-20

    A research program to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating inexpensive ceramic substrates with a thin layer of polycrystalline silicon is described. The coating methods to be developed are directed toward a minimum-cost process for producing solar cells with a terrestrial conversion efficiency of 12 percent or greater. By applying a graphite coating to one face of a ceramic substrate, molten silicon can be caused to wet only that graphite-coated face and produce uniform thin layers of large-grain polycrystalline silicon; thus, only a minimal quantity of silicon is consumed. A dip-coating method for putting silicon on ceramic (SOC) has been shown to produce solar-cell-quality sheet silicon. This method and a continuous coating process also being investigated have excellent scale-up potential which offers an outstanding cost-effective way to manufacture large-area solar cells. A variety of ceramic materials have been dip-coated with silicon. The investigation has shown that mullite substrates containing an excess of SiO/sub 2/ best match the thermal expansion coefficient of silicon and hence produce the best SOC layers. With such substrates, smooth and uniform silicon layers 25 cm/sup 2/ in area have been achieved with single-crystal grains as large as 4 mm in width and several cm in length. Solar cells with areas from 1 to 10 cm/sup 2/ have been fabricated from material withas-grown surface. Recently, an antireflection (AR) coating has been applied to SOC cells. Conversion efficiencies greater than 9% have been achieved without optimizing series resistance characteristics. Such cells typically have open-circuit voltages and short-circuit current densities of 0.51 V and 20 mA/cm/sup 2/, respectively.

  19. NREL Invention Speeds Solar Cell Quality Testing for Industry (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2013-08-01

    A solid-state optical system, invented by the National Renewable Energy Laboratory (NREL), measures solar cell quantum efficiency (QE) in less than a second, enabling a suite of new capabilities for solar cell manufacturers. QE is a measurement of how cells respond to light across the solar spectrum, but traditional methods for measuring QE had been too slow, limiting its application to small samples pulled from the production line and analyzed in laboratories. NREL's technique, commercialized by Tau Science as the FlashQE(TM) system, uses a solid-state light source, synchronized electronics, and advanced mathematical analysis to parallel-process QE data in a tiny fraction of the time required by the current method, allowing its use on every solar cell passing through a production line.

  20. Silicon on Ceramic Process: Silicon Sheet Growth and Device Development for the Large-area Silicon Sheet and Cell Development Tasks of the Low-cost Solar Array Project

    Science.gov (United States)

    Chapman, P. W.; Zook, J. D.; Heaps, J. D.; Pickering, C.; Grung, B. L.; Koepke, B.; Schuldt, S. B.

    1979-01-01

    The technical and economic feasibility of producing solar cell quality sheet silicon was investigated. It was hoped this could be done by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. Work was directed towards the solution of unique cell processing/design problems encountered with the silicon-ceramic (SOC) material due to its intimate contact with the ceramic substrate. Significant progress was demonstrated in the following areas; (1) the continuous coater succeeded in producing small-area coatings exhibiting unidirectional solidification and substatial grain size; (2) dip coater succeeded in producing thick (more than 500 micron) dendritic layers at coating speeds of 0.2-0.3 cm/sec; and (3) a standard for producing total area SOC solar cells using slotted ceramic substrates was developed.

  1. Amniotic membrane allografts: development and clinical utility in ophthalmology

    Directory of Open Access Journals (Sweden)

    Rizzuti A

    2014-12-01

    Full Text Available Allison Rizzuti,1,2 Adam Goldenberg,1 Douglas R Lazzaro1,2 1SUNY Downstate Medical Center, 2Kings County Hospital Center, Brooklyn, NY, USA Abstract: Amniotic membrane, the innermost layer of the placenta, is a tissue that promotes epithelialization, while decreasing inflammation, neovascularization, and scarring. It is used in the surgical management of a wide variety of ophthalmic conditions where it functions as a graft or patch in ocular surface reconstruction. The development of new preservation techniques, as well as a sutureless amniotic membrane, has allowed for easier, in-office placement, without the disadvantages of an operating room procedure. The purpose of this review is to describe the historical development of amniotic membrane in ophthalmology and to describe its current clinical applications, particularly focusing on recent advances. Keywords: ocular surface, cornea, stem cells, prokera, allograft, patch, transplantation

  2. Successful matrix guided tissue regeneration of decellularized pulmonary heart valve allografts in elderly sheep.

    Science.gov (United States)

    Theodoridis, Karolina; Tudorache, Igor; Calistru, Alexandru; Cebotari, Serghei; Meyer, Tanja; Sarikouch, Samir; Bara, Christoph; Brehm, Ralph; Haverich, Axel; Hilfiker, Andres

    2015-06-01

    In vivo repopulation of decellularized allografts with recipient cells leads to a positive remodeling of the graft matrix in juvenile sheep. In light of the increasing number of heart valve replacements among older patients (>65 years), this study focused on the potential for matrix-guided tissue regeneration in elderly sheep. Pulmonary valve replacement was performed in seven-year old sheep using decellularized (DV), decellularized and CCN1-coated (RV), or decellularized and in vitro reendothelialized pulmonary allografts (REV) (n=6, each group). CCN1 coating was applied to support re-endothelialization. In vitro re-endothelialization was conducted with endothelial-like cells derived from peripheral blood. Echocardiograms of all grafts showed adequate graft function after implantation and at explantation 3 or 6 months later. All explants were macroscopically free of thrombi at explantation, and revealed repopulation of the allografts on the adventitial side of valvular walls and proximal in the cusps. Engrafted cells expressed vimentin, sm α-actin, and myosin heavy chain 2, while luminal cell lining was positive for vWF and eNOS. Cellular repopulation of valvular matrix demonstrates the capacity for matrix-guided regeneration even in elderly sheep but is not improved by in vitro endothelialization, confirming the suitability of decellularized matrix for heart valve replacement in older individuals.

  3. Allograft of microencapsulated ovarian cells affects bone collagen metabolism in ovariectomized mice%卵巢细胞微囊移植对去卵巢小鼠的骨胶原代谢的影响

    Institute of Scientific and Technical Information of China (English)

    郭晓霞; 周金玲; 许晴; 史小林

    2011-01-01

    BACKGROUND: Gonad hormones are essential for the maintenance of skeletal integrity. The in vitro cultured ovarian cells can secrete estradiol and progesterone. Alginic acid-polylysine-alginic acid microcapsule provides a barrier between the graft and the recipient, thus promoting the survival of heterotransplants.OBJECTIVE: To explore the survival and secretion functions of allografted microencapsulated ovarian cells in ovariectomized mice and their effect on bone collagen metabolism after ovariectomy (OVX).METHODS: Ovarian cells separated from female Kunming mice (6 weeks old) were cultured and microencapsulated with alginic acid-polylysine-alginic acid. A total of 24 female Kunming mice (8 weeks old) were randomly divided into three groups (n=8):normal group: OVX was not performed; OVX group: OVX was performed; transplantation group: microencapsulated ovarian cells were transplanted into abdominal cavity after OVX. Estradiol and/or progesterone levels of the medium of microencapsulated ovarian cells and mice serum were determined by radioimmunoassay. Ⅰ type collagen fibers in the bone matrix were showed by Van Gieson staining. The concentrations of hydroxyproline, Ca, and P were measured in the left femurs of mice.RESULTS AND CONCLUSION: The concentrations of estradiol and progesterone in the culture medium were not significantly different between the cultured ovarian cells and microencapsulated ovarian cells. The serum estradiol concentration at 90 days after transplantation had no significant difference compared with that of normal group, whereas the serum estradiol concentration of the OVX group was significantly lower than that of the normal group. In the transplantation group, the distribution of collagen fibers was similar to that of the normal group determined by Van Gieson staining. In comparison to the normal group, the OVX group had less, thinner trabecular matrix, and fewer collagen fibers, more free trabecular terminals, and a thinner uncalcified

  4. NREL Explores Earth-Abundant Materials for Future Solar Cells (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-10-01

    Researchers at the National Renewable Energy Laboratory (NREL) are using a theory-driven technique - sequential cation mutation - to understand the nature and limitations of promising solar cell materials that can replace today's technologies. Finding new materials that use Earth-abundant elements and are easily manufactured is important for large-scale solar electricity deployment.

  5. Adhesion, resistivity and structural, optical properties of molybdenum on steel sheet coated with barrier layer done by sol–gel for CIGS solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Amouzou, Dodji, E-mail: dodji.amouzou@fundp.ac.be [Research Centre in Physics of Matter and Radiation (PMR), University of Namur (FUNDP), Rue de Bruxelles 61, 5000 Namur (Belgium); Dumont, Jacques [Research Centre in Physics of Matter and Radiation (PMR), University of Namur (FUNDP), Rue de Bruxelles 61, 5000 Namur (Belgium); Fourdrinier, Lionel; Richir, Jean-Baptiste; Maseri, Fabrizio [CRM-Group, Boulevard de Colonster, B 57, 4000 Liège (Belgium); Sporken, Robert [Research Centre in Physics of Matter and Radiation (PMR), University of Namur (FUNDP), Rue de Bruxelles 61, 5000 Namur (Belgium)

    2013-03-01

    Molybdenum films are investigated on stainless steel substrates coated with polysilazane based sol–gel and SiO{sub x} layers for flexible CIGS solar cell applications. Thermal stability of the multilayer has been studied. The thickness of polysilazane films are significantly reduced (17%) after heat treatment suggesting a thermal degradation. Four different microstructures were found for Mo films by varying argon total pressure from 2.6 × 10{sup −1} Pa to 2.6 Pa. It was shown that continuous films, low sheet resistance (0.5 Ω/□) and well facetted grains can be achieved when Mo films are deposited on heated substrates at homologous temperature, T of 0.2. - Highlights: ► Steel sheet is functionalized for Cu[Inx,Ga(1 − x)Se2] solar cells. ► Varying deposition pressure impacts the microstructure of Mo films. ► High thermal stability of the sol gel based barrier layer has been investigated. ► Low sheet resistance and continuous Mo films have been obtained at 550°C. ► Thermal stability of functionalized steel sheets at 550°C has been investigated.

  6. Use of local allograft irradiation following renal transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Halperin, E.C.; Delmonico, F.L.; Nelson, P.W.; Shipley, W.U.; Cosimi, A.B.

    1984-07-01

    Over a 10 year period, 67 recipients of 71 renal allografts received graft irradiation following the diagnosis of rejection. The majority of kidneys were treated with a total dose of 600 rad, 150 rad per fraction, in 4 daily fractions. Fifty-three kidneys were irradiated following the failure of standard systemic immunosuppression and maximally tolerated antirejection measures to reverse an episode of acute rejection. Twenty-two (42%) of these allografts were noted to have stable (i.e. no deterioration) or improved function 1 month following the treatment with irradiation. Eleven (21%) of these allografts maintained function 1 year following transplantation. Biopsies were obtained of 41 allografts. Of the 24 renal allografts with predominantly cellular rejection, 10 (42%) had the process reversed or stabilized at 1 month following irradiation. Five (21%) of these allografts were functioning at 1 year following irradiation. Rejection was reversed or stabilized in 6 of 17 (35%) allografts at 1 month when the histologic features of renal biopsy suggested predominantly vascular rejection. Local graft irradiation has helped maintain a limited number of allografts in patients whose rejection has failed to respond to systemic immunosuppression. Irradiation may also benefit patients with ongoing rejection in whom further systemic immunosuppression is contra-indicated.

  7. Role of interleukin-17 and Th17 cells in acute renal allograft rejection in mice%白细胞介素-17与Th17细胞在小鼠肾移植急性排斥反应中的表达及意义

    Institute of Scientific and Technical Information of China (English)

    司中洲; 李亭; 李杰群; 齐海智; 谢续标

    2011-01-01

    Objective To investigate the role of Thl7 cells and the cytokine interleukin-17 (IL-17) in acute allograft rejection in mice. Methods Mouse models of kidney transplantation were randomly divided into rejection group and isograft group. On the post-operative day (POD) 3 and 7, we tested the serum IL-17 level using enzyme-linked immunosorbent assay and measured the number of Thl7 cells in the renal grafts by flow cytometry. The grafts were harvested and fixed in 10% formalin to prepare paraffin sections for routine pathological inspection. Results Compared to isograft group, the allograft group showed a significantly higher level of serum IL-17 on POD3 and POD7 (P<0.05), and the level of IL-17 is significantly higher on POD7 than on POD3 (P0<.05). The allograft group showed more infiltrating Thl7 cells in the grafts on POD3 and POD7 (P<0.05), and the cell number was significantly greater on POD7 (P<0.05). Pathological examination also showed an increased severity of graft rejection with the post-transplantation time. Conclusion Thl7 cells may play an important role in the development of renal graft rejection. IL-17 may serve as a potential specific indicator for predicting allograft rejection.%目的 研究Thl7细胞及相关因子白细胞介素17(IL-17)在小鼠肾移植排斥反应中的表达及意义.方法 建立小鼠肾移植模型,实验动物随机分为同系移植组和急性排斥反应组,在移植术后3d和7d,分别应用酶联免疫吸附实验检测两组小鼠血清中IL-17含量,应用流式细胞术检测移植肾中浸润淋巴细胞中Th17细胞数量,取移植肾经10%福尔马林固定后行常规病理检查.结果 与同系移植组相比,急性排斥反应组术后第3天及第7大血清中IL-17含量均升高(P<0.05),且术后第7天时IL-17含量明显高于第3天(P<0.05);急性排斥反应组移植肾中浸润淋巴细胞中Th17细胞比例在术后第3天及第7天较『司系移植组均明显增多(P<0.05),

  8. New Fabrication Method Improves the Efficiency and Economics of Solar Cells (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-07-01

    Synthetic fabrication strategy optimizes the illumination geometry and transport properties of dye-sensitized solar cells. Using oriented titanium oxide (TiO{sub 2}) nanotube (NT) arrays has shown promise for dye-sensitized solar cells (DSSCs). High solar conversion efficiency requires that the incident light enters the cell from the photoelectrode side. However, for NT-based DSSCs, the light normally enters the cell through the counter electrode because a nontransparent titanium foil is typically used as the substrate for forming the aligned NTs and for making electrical contact with them. It has been synthetically challenging to prepare transparent TiO{sub 2} NT electrodes by directly anodizing Ti metal films on transparent conducting oxide (TCO) substrates because it is difficult to control the synthetic conditions. National Renewable Energy Laboratory (NREL) researchers have developed a general synthetic strategy for fabricating transparent TiO{sub 2} NT films on TCO substrates. With the aid of a conducting Nb-doped TiO{sub 2} (NTO) layer between the Ti film and TCO substrate, the Ti film can be anodized completely without degrading the TCO. The NTO layer protects the TCO from degradation through a self-terminating mechanism by arresting the electric field-assisted dissolution process at the NT-NTO interface. NREL researchers found that the illumination direction and wavelength of the light incident on the DSSCs strongly influenced the incident photon-to-current conversion efficiency, light-harvesting, and charge-collection properties, which, in turn, affect the photocurrent density, photovoltage, and solar energy conversion efficiency. Researchers also examined the effects of NT film thickness on the properties and performance of DSSCs and found that illuminating the cell from the photoelectrode side substantially increased the conversion efficiency compared with illuminating it from the counter-electrode side. This method solves a key challenge in fabricating

  9. Interest of Polyelectrolyte Multilayer thin Films in Tissue Engineering:Application to Vascular Allograft

    Institute of Scientific and Technical Information of China (English)

    Halima; KERDJOUDJ; Cedric; BOURA; Vanessa; MOBY; Dominique; DUMAS; Luc; MARCHAL; Jean-Claude; VOEGEL; Jean-Franois; STOLTZ; Patrick; MENU

    2005-01-01

    1 Introduction Obstructive atherosclerosis vascular disease remains one of the greatest public health threats in the world. Surgical treatment to replace diseased blood vessels is usually done using major human allografts (veins or arteries) or synthetic prosthesis (PTFE, Dacron). However, these substitutes have not a good patency, because of the lack of endothelial cells (ECs) layer, which prevents thrombus formation. The challenge of tissue engineering vessels is to build-up blood/substitute interface nea...

  10. Post-transplant Lymphoproliferative Disorder Arising from Renal Allograft Parenchyma: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byung Kwan; Kim, Chan Kyo; Kwon, Ghee Young [Samsung Medical Center, Sungkyunkwan University College of Medicine, Seoul (Korea, Republic of)

    2010-06-15

    Post-transplant lymphoproliferative disorder (PTLD) is a rare but serious complication that occurs in patients undergoing kidney transplantation. PTLD usually manifests as a renal hilar mass comprised of histologically B-lymphocytes. We report our experience of managing a patient with PTLD arising from renal parenchyma. Ultrasonographic and MR imaging features of this unusual PTLD suggested differentiated renal cell carcinoma arising from the renal allograft

  11. Consecutive Low Doses of Cyclosporine A Induce Pro-Inflammatory Cytokines and Accelerate Allograft Skin Rejection

    Directory of Open Access Journals (Sweden)

    Luis I. Terrazas

    2011-05-01

    Full Text Available Cyclosporine A (CsA is a fungus-derived molecule with potent immunosuppressive activity that has been largely used to downregulate cell-mediated immune responses during transplantation. However, previous data have indicated that CsA shows immunomodulatory activity that relays on the antigen concentration and the dose of CsA used. To test the hypothesis that minimal doses of CsA may show different outcomes on grafts, we used an experimental model for skin transplants in mice. ICR outbred mice received skin allografts and were either treated daily with different doses of CsA or left untreated. Untreated mice showed allograft rejection within 14 days, with graft necrosis, infiltration of neutrophils and macrophages and displayed high percentages of CD8+ T cells in the spleens, which were associated with high serum levels of IL-12, IFN-g and TNF-α. As expected, mice treated with therapeutic doses of CsA (15 mg/kg did not show allograft rejection within the follow-up period of 30 days and displayed the lowest levels of IL-12, IFN-g and TNF-α as well as a reduction in CD8+ lymphocytes. In contrast, mice treated with consecutive minimal doses of CsA (5 × 10−55 mg/kg displayed an acute graft rejection as early as one to five days after skin allograft; they also displayed necrosis and strong inflammatory infiltration that was associated with high levels of IL-12, IFN-g and TNF-α. Moreover, the CD4+ CD25hiFoxP3+ subpopulation of cells in the spleens of these mice was significantly inhibited compared with animals that received the therapeutic treatment of CsA and those treated with placebo. Our data suggest that consecutive, minimal doses of CsA may affect Treg cells and may stimulate innate immunity.

  12. Recent developments in low cost silicon solar cells for terrestrial applications. [sheet production methods

    Science.gov (United States)

    Leipold, M. H.

    1978-01-01

    A variety of techniques may be used for photovoltaic energy systems. Concentrated or not concentrated sunlight may be employed, and a number of materials can be used, including silicon, gallium arsenide, cadmium sulfide, and cadmium telluride. Most of the experience, however, has been obtained with silicon cells employed without sunlight concentration. An industrial base exists at present for producing solar cells at a price in the range from $15 to $30 per peak watt. A major federal program has the objective to reduce the price of power provided by silicon solar systems to approximately $1 per peak watt in the early 1980's and $0.50 per watt by 1986. The approaches considered for achieving this objective are discussed.

  13. Quantum Dots Promise to Significantly Boost Solar Cell Efficiencies (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2013-08-01

    In the search for a third generation of solar-cell technologies, a leading candidate is the use of 'quantum dots' -- tiny spheres of semiconductor material measuring only about 2-10 billionths of a meter in diameter. Quantum dots have the potential to dramatically increase the efficiency of converting sunlight into energy -- perhaps even doubling it in some devices -- because of their ability to generate more than one bound electron-hole pair, or exciton, per incoming photon. NREL has produced quantum dots using colloidal suspensions; then, using molecular self-assembly, they have been fabricated into the first-ever quantum-dot solar cells. While these devices operate with only 4.4% efficiency, they demonstrate the capability for low-cost manufacturing.

  14. Dielectrophoresis-assisted massively parallel cell pairing and fusion based on field constriction created by a micro-orifice array sheet.

    Science.gov (United States)

    Kimura, Yuji; Gel, Murat; Techaumnat, Boonchai; Oana, Hidehiro; Kotera, Hidetoshi; Washizu, Masao

    2011-09-01

    In this paper, we present a novel electrofusion device that enables massive parallelism, using an electrically insulating sheet having a two-dimensional micro-orifice array. The sheet is sandwiched by a pair of micro-chambers with immersed electrodes, and each chamber is filled with the suspensions of the two types of cells to be fused. Dielectrophoresis, assisted by sedimentation, is used to position the cells in the upper chamber down onto the orifices, then the device is flipped over to position the cells on the other side, so that cell pairs making contact in the orifice are formed. When a pulse voltage is applied to the electrodes, most voltage drop occurs around the orifice and impressed on the cell membrane in the orifice. This makes possible the application of size-independent voltage to fuse two cells in contact at all orifices exclusively in 1:1 manner. In the experiment, cytoplasm of one of the cells is stained with a fluorescence dye, and the transfer of the fluorescence to the other cell is used as the indication of fusion events. The two-dimensional orifice arrangement at the pitch of 50 μm realizes simultaneous fusion of 6 × 10³ cells on a 4 mm diameter chip, and the fusion yield of 78-90% is achieved for various sizes and types of cells.

  15. The Effect of Resveratrol Combined with Tacrolimus on CD4+/CD8+ T Cells in Rat Renal Allografts%白藜芦醇联合他克莫司对大鼠移植肾CD4+/CD8+T细胞的影响

    Institute of Scientific and Technical Information of China (English)

    钱坤; 龙建华; 蒋鸿涛

    2014-01-01

    Objective: To investigate the effect of resveratrol(RES) combined with tacrolimus(FK506)on CD4+/CD8+ T cells in rats renal allografts, and assess the possibility that RES synergizes FK506 based immunosuppressant, thus acting as an clinical immunosuppressive combination to promote renal allograft survival and function.Method: Renal allogenic grafting was performed on BN rats as donors and LEW rats as recipients. Forty-eight male LEW rats were randomly divided into four groups: control group(n=12), RES group(n=12), FK506 group(n=12), FK506+RES group(n=12), and then interventions were made from day 1 before renal transplantation (RTx). In each group, survival lengths of rats(n=6) were recorded in each group after RTx, and also CD4+ and CD8+ T-cell infiltration in renal grafts of rats(n=6) were analyzed by immunohistochemistry on day 6 after RTx.Result: Renal allograft survival in FK506+RES group was markedly prolonged as compared to other groups, and the difference were all statistically significant(P<0.05). A significant decrease of CD4+ and CD8+ T cells infiltration into the graft was demonstrated in FK506+RES group as compared to other groups, and the difference were all statistically significant(P<0.05).Conclusion: RES and FK506 exert synergistic effect towards markedly decreasing CD4+ and CD8+ T cells infiltration into the graft of rat, decreasing rejection, and further enhancing rat renal allograft survival. We hypothesized that novel therapeutic approaches involving combination of RES with FK506 will produce potential beneficial outcomes in clinical renal transplantation.%目的:观察白藜芦醇(RES)联合他克莫司(FK506)对大鼠移植肾CD4+/CD8+T细胞的影响,探讨将RES应用于肾移植领域的价值。方法:以BN大鼠为供体,LEW大鼠为受体,建立大鼠同种异体肾移植模型。将48只受体大鼠按照随机数字表法均分为对照组、RES组、FK506组、RES+FK506组,术前1 d开始进行药物干预。记录每组6

  16. Wrapping of a single bacterium with Functionalized - Chemically Modified Graphene (FCMG) sheets via highly specific protein-cell wall interaction

    Science.gov (United States)

    Mohanty, Nihar; Berry, Vikas

    2009-03-01

    Graphene has recently generated a lot of interest due to its unique structural and electrical properties. It's micro-scale area and sub-nano-scale thickness coupled with ballistic electronic transport at room temperature, low Johnston noise and low charge scattering, have made it a gold mine for novel applications. Since its discovery in 2004, there have been a plethora of studies on characterizing its unique physical, chemical and electrical properties of graphene as well as on integrating it with various physical/chemical systems to utilize these properties. But there have been limited or no studies on the integration of graphene with living microorganisms or mammalian cells. Here we describe the novel wrapping of a single live bacterium (Bacillus cereus) with a chemically modified graphene sheet functionalized with the protein Concanavalin-A (Con-A) via the highly specific Con-A - Teichoic acid interaction. We are investigating the structural and the electrical properties of these novel bacteria-FCMG ensembles. Further, we are also interested in characterizing this wrapping process in detail by studying the kinetics and the mechanism of action of bacterial-wrapping via 3D modelling. This is a first step towards the live-bio-nano-integration of graphene which would open up avenues for applications as diverse as bio-batteries using the Geobacter to recombinant enzyme compartmentalization.

  17. Calcineurin inhibitor toxicity in renal allografts: Morphologic clues from protocol biopsies

    Directory of Open Access Journals (Sweden)

    Sharma Alok

    2010-10-01

    Full Text Available Background: Calcineurin inhibitors (cyclosporine and tacrolimus are important constituents of post renal transplant immunosuppression. However, renal toxicity limits their utility. Histological features of calcineurin inhibitor toxicity (CNIT have been the subject of few studies using protocol biopsy samples, and consensus on diagnostic criteria is still evolving. Aims: To analyze the spectrum of histological changes in protocol renal allograft biopsies with evidence of CNIT and identify additional features that are likely to help the pathologist in arriving at a diagnosis. Materials and Methods: One hundred and forty protocol allograft biopsies performed at 1, 6 and 12 months post renal transplant were studied. The defining features of CNIT included: isometric vacuolization of proximal tubular cells, arteriolar hyalinosis with medial/peripheral nodules and striped pattern of tubular atrophy/interstitial fibrosis. Other features such as global glomerulosclerosis, vacuolization of smooth muscle cells of arterioles, tubular microcalcinosis, ischemic shrinkage of glomeruli and hyperplasia of juxtaglomerular apparatus (JGA were also analyzed and graded semiquantitatively. Results: CNIT was seen in 17/140 protocol biopsies (12.1%. In addition to the diagnostic criteria, arteriolar hyalinosis, smooth muscle cell vacuolization of arterioles and hyperplasia of JGA were found to be useful indicators of CNIT. Conclusions: There is a relatively high incidence of CNIT in protocol allograft biopsies. A critical analysis of renal biopsy in adequate number of serial step sections to identify these features is mandatory, as many of these features are subtle and are likely to be missed if not specifically sought.

  18. 调节性T细胞对输注树突状细胞后小鼠移植心脏的保护作用%The protective effects of CD4+ CD25+ Treg cell on the allograft after infusion of dendritic cells with low expression of CD40 from donor in mouse heart transplantation

    Institute of Scientific and Technical Information of China (English)

    朱杰昌; 付蔚华; 许翼麟; 朱理玮

    2013-01-01

    Objective To explore the effects of CD4+CD25+Treg cell on the allograft after infusion of dendritic cells (DCs) with low expression of CD40 from donor in mouse heart transplantation.Methods In vitro,mouse bone marrow-derived DCs were infected by CD40-RNAi lentiviral vector,and tolerogenic DCs (Tol-DCs) with low expression of CD40 were prepared.A heterotopic abdominal heart transplantation model was established in mice,and the other three groups that were control group,noninfected DC group and lentivirus infected DC group were designed correspondingly.Cardiac allograft survival time was recorded and pathological grading for acute rejection was assessed on the 7 d after heterotopic abdominal heart transplantation.Concentrations of CD4+CD25+Treg cells in peripheral blood were analyzed before and after transplantation by flow cytometry.Results After 48 h infection of DCs by CD40-RNAi lentiviral vector in vitro,the expression of CD40 mRNA was down-regulated significantly,whose inhibition rate was 80.9%.The expression of CD40 was decreased from 74.37% ±4.08% to 40.07% ± 4.03% (P<0.05) after 48 h infection.Compared with the control group and the noninfected DC group,the cardiac allograft survival time was significantly prolonged in the CD40-RNAi lentivirus infected DC group,which was (14 ± 4) d(P<0.01) ; concentrations of CD4+CD25+Treg cells in peripheral blood were increased both on the 3 d and the 7 d after transplantation (P<0.05) ; the pathological grading for acute rejection was decreased on the 7 d after transplantation (P<0.05).Conclusion The CD4+CD25+Treg cell in peripheral blood was protective to cardiac allograft in prolonging its survival time in mouse heart transplantation.%目的 探讨在输注供者低表达CD40的树突状细胞(dendritic cells,DC)后,调节性T细胞(regulatory T cell,Treg)对小鼠移植心脏的保护作用.方法 以针对小鼠CD40基因的RNA干扰(RNA interference,RNAi)慢病毒载体在体外感染供者骨髓

  19. OSTEOARTICULAR ALLOGRAFTS IN PAEDIATRIC BONE TUMOR RECONSTRUCTION OF THE KNEE.

    Science.gov (United States)

    Campanacci, D A; Dursky, S; Totti, F; Frenos, F; Scoccianti, G; Beltrami, G; Capanna, R

    2015-01-01

    Osteoarticular allografts represent a reconstructive option after bone tumor resection around the knee in growing children. The major advantage is the chance to preserve the growth plate of the remaining bone, but the disadvantage is the high failure rate eventually requiring definitive prosthetic replacement at skeletal maturity. We retrospectively reviewed 22 patients who underwent osteoarticular allograft reconstructions of the distal femur (16) or proximal tibia (6). There were 12 females and 10 males with an average age at surgery of 11 years (7-15). The diagnosis was osteosarcoma in 19 cases and Ewing sarcoma in 3. All patients underwent pre- and post-operative chemotherapy. At an average follow-up of 103 months (12-167), 18 patients (82%) were alive and 4 had died (18%). We observed 10 allograft failures requiring prosthetic replacement, 6 in distal femur and 4 in proximal tibia reconstructions. At last follow-up 8 allografts (36%) were still in place. Overall allograft survival was 79.6% at five and 45.8% at ten years. In distal femur, allograft survival was 86.2% at five and 59.1% at ten years. In proximal tibia, allograft survival was 62.5% at 5 years and 31.2% at 67 months. Average limb shortening was 3 cm (0- 5) in 8 patients with the allograft still in situ and 2 cm (0-4) in 10 patients after prosthetic replacement. Average MSTS functional score of the whole series was 25 (83.7%). The MSTS score of patients after revision with prosthetic replacement was 24 (80%) while patients who still had the allograft retained had an average MSTS scores of 26.8 (89.3%). In conclusion, osteoarticular allograft reconstruction of the knee after bone tumor resection in pediatric age can be considered a temporary solution with the aim to limit limb length discrepancy before definitive prosthetic replacement after skeletal maturity.

  20. Semaphorin 3A-modified adipose-derived stem cell sheet may improve osseointegration in a type 2 diabetes mellitus rat model

    Science.gov (United States)

    Fang, Kaixiu; Song, Wen; Wang, Lifeng; Xu, Xiaoru; Tan, Naiwen; Zhang, Sijia; Wei, Hongbo; Song, Yingliang

    2016-01-01

    Although titanium (Ti) implants are considered to be an optimal choice for the replacement of missing teeth, it remains difficult to obtain sufficient osseointegration in patients with type 2 diabetes mellitus (T2DM). The present study aimed to investigate whether adipose-derived stem cells (ASCs) may be used to improve Ti implant osseointegration in T2DM conditions with the addition of semaphorin 3A (Sema3A), a recently identified osteoprotective protein. Cell morphology was observed using a scanning electron microscope. Cell proliferation was determined using Cell Counting Kit-8. Osteogenic differentiation was confirmed by the staining of alkaline phosphatase, collagen secretion and calcium deposition. An in vivo evaluation was performed in the T2DM rat model, which was induced by a high-fat diet and a low-dose streptozotocin intraperitoneal injection. A Sema3A-modified ASC sheet was wrapped around the Ti implant, which was subsequently inserted into the tibia. The rats were then exposed to Sema3A stimulation. The morphology and proliferation ability of ASCs remained unchanged; however, their osteogenic differentiation ability was increased. Micro-computed tomography scanning and histological observations confirmed that formation of new bone was improved with the use of the Sema3A-modified ASCs sheet. The present study indicated that the Sema3A-modified ASCs sheet may be used to improve osseointegration under T2DM conditions. PMID:27484405

  1. Sterilization with electron beam irradiation influences the biomechanical properties and the early remodeling of tendon allografts for reconstruction of the anterior cruciate ligament (ACL).

    Science.gov (United States)

    Schmidt, Tanja; Hoburg, Arnd; Broziat, Christine; Smith, Mark D; Gohs, Uwe; Pruss, Axel; Scheffler, Sven

    2012-08-01

    Although allografts for anterior cruciate ligament (ACL) replacement have shown advantages compared to autografts, their use is limited due to the risk of disease transmission and the limitations of available sterilization methods. Gamma sterilization has shown detrimental effects on graft properties at the high doses required for sufficient pathogen inactivation. In our previous in vitro study on human patellar tendon allografts, Electron beam (Ebeam) irradiation showed less detrimental effects compared to gamma sterilization (Hoburg et al. in Am J Sports Med 38(6):1134-1140, 2010). To investigate the biological healing and restoration of the mechanical properties of a 34 kGy Ebeam treated tendon allograft twenty-four sheep underwent ACL replacement with either a 34 kGy Ebeam treated allograft or a non-sterilized fresh frozen allograft. Biomechanical testing of stiffness, ultimate failure load and AP-laxity as well as histological analysis to investigate cell, vessel and myofibroblast-density were performed after 6 and 12 weeks. Native sheep ACL and hamstring tendons (HAT, each n = 9) served as controls. The results of a previous study analyzing the remodeling of fresh frozen allografts (n = 12) and autografts (Auto, n = 18) with the same study design were also included in the analysis. Statistics were performed using Mann-Whitney U test followed by Bonferroni-Holm correction. Results showed significantly decreased biomechanical properties during the early remodeling period in Ebeam treated grafts and this was accompanied with an increased remodeling activity. There was no recovery of biomechanical function from 6 to 12 weeks in this group in contrast to the results observed in fresh frozen allografts and autografts. Therefore, high dose Ebeam irradiation investigated in this paper cannot be recommended for soft tissue allograft sterilization.

  2. Massive allograft replacement in management of bone tumors%冷冻异体骨移植治疗骨肿瘤切除后骨缺损

    Institute of Scientific and Technical Information of China (English)

    Xiaohui Niu; Lin Hao; Qing Zhang; Yi Ding

    2008-01-01

    Objective: To evaluate the functional outcome and complications of allograft replacement in management of bone tumors. Methods: Between March 1992 and September 2002, 164 patients underwent bone tumor resection and massive allograft reconstruction of bone defects. The length of the resected part ranged from 5-35 cm. The resections were dassified as marginal or wide resections of the tumor on the basis of the Musculoskeletal Tumor Society staging system. Fresh-frozen allografts were employed as osteoarticular grafts (n = 95), hemi-condylar (n = 15), massive (n = 23), allograft-prosthesis composite (n=12), intercalary grafts (n=15) or hemi-pelvic grafts (n=4). Most of the lesions were osteosarcoma and giant cell tumor of bone and located in proximal and distal femur, proximal tibia and humerus. Results: At a median follow-up of 47 months (range, 12 to 168 months) after the operation, 154 of the patients in the study were free of disease and 10 died of disease. Twenty-one (12.8%) patients had local recurrence and 38 (23.2%) nonunion. Late complications included 11 (6.7%)fractures of the allograft and 18 (11.0%) infections of the graft. Instability of the joint in the form of subluxation was noted in 13 (7.9%) patients. Ten extremities were amputated due to local recurrence or severe infection. Conclusion: Allografts can be used for reconstruction of bony defects after tumor resection. Allograft has nearly similar shape, strength, osteo-inductivity and osteo-conductivity with host bone. Allograft implantation is a high complication reconstruction method, and the risk of recurrence increases when less surgical margin achieves.

  3. Ocular surface reconstruction with a tissue-engineered nasal mucosal epithelial cell sheet for the treatment of severe ocular surface diseases.

    Science.gov (United States)

    Kobayashi, Masakazu; Nakamura, Takahiro; Yasuda, Makoto; Hata, Yuiko; Okura, Shoki; Iwamoto, Miyu; Nagata, Maho; Fullwood, Nigel J; Koizumi, Noriko; Hisa, Yasuo; Kinoshita, Shigeru

    2015-01-01

    Severe ocular surface diseases (OSDs) with severe dry eye can be devastating and are currently some of the most challenging eye disorders to treat. To investigate the feasibility of using an autologous tissue-engineered cultivated nasal mucosal epithelial cell sheet (CNMES) for ocular surface reconstruction, we developed a novel technique for the culture of nasal mucosal epithelial cells expanded ex vivo from biopsy-derived human nasal mucosal tissues. After the protocol, the CNMESs had 4-5 layers of stratified, well-differentiated cells, and we successfully generated cultured epithelial sheets, including numerous goblet cells. Immunohistochemistry confirmed the presence of keratins 3, 4, and 13; mucins 1, 16, and 5AC; cell junction and basement membrane assembly proteins; and stem/progenitor cell marker p75 in the CNMESs. We then transplanted the CNMESs onto the ocular surfaces of rabbits and confirmed the survival of this tissue, including the goblet cells, up to 2 weeks. The present report describes an attempt to overcome the problems of treating severe OSDs with the most severe dry eye by treating them using tissue-engineered CNMESs to supply functional goblet cells and to stabilize and reconstruct the ocular surface. The present study is a first step toward assessing the use of tissue-engineered goblet-cell transplantation of nonocular surface origin for ocular surface reconstruction.

  4. Interleukin-6, A Cytokine Critical to Mediation of Inflammation, Autoimmunity and Allograft Rejection: Therapeutic Implications of IL-6 Receptor Blockade.

    Science.gov (United States)

    Jordan, Stanley C; Choi, Jua; Kim, Irene; Wu, Gordon; Toyoda, Mieko; Shin, Bonga; Vo, Ashley

    2017-01-01

    The success of kidney transplants is limited by the lack of robust improvements in long-term survival. It is now recognized that alloimmune responses are responsible for the majority of allograft failures. Development of novel therapies to decrease allosensitization is critical. The lack of new drug development in kidney transplantation necessitated repurposing drugs initially developed in oncology and autoimmunity. Among these is tocilizumab (anti-IL-6 receptor [IL-6R]) which holds promise for modulating multiple immune pathways responsible for allograft injury and loss. Interleukin-6 is a cytokine critical to proinflammatory and immune regulatory cascades. Emerging data have identified important roles for IL-6 in innate immune responses and adaptive immunity. Excessive IL-6 production is associated with activation of T-helper 17 cell and inhibition of regulatory T cell with attendant inflammation. Plasmablast production of IL-6 is critical for initiation of T follicular helper cells and production of high-affinity IgG. Tocilizumab is the first-in-class drug developed to treat diseases mediated by IL-6. Data are emerging from animal and human studies indicating a critical role for IL-6 in mediation of cell-mediated rejection, antibody-mediated rejection, and chronic allograft vasculopathy. This suggests that anti-IL-6/IL-6R blockade could be effective in modifying T- and B-cell responses to allografts. Initial data from our group suggest anti-IL-6R therapy is of value in desensitization and prevention and treatment of antibody-mediated rejection. In addition, human trials have shown benefits in treatment of graft versus host disease in matched or mismatched stem cell transplants. Here, we explore the biology of IL-6/IL-6R interactions and the evidence for an important role of IL-6 in mediating allograft rejection.

  5. Glycosylation Helps Cellulase Enzymes Bind to Plant Cell Walls (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-06-01

    Computer simulations suggest a new strategy to design enhanced enzymes for biofuels production. Large-scale computer simulations predict that the addition of glycosylation on carbohydrate-binding modules can dramatically improve the binding affinity of these protein domains over amino acid mutations alone. These simulations suggest that glycosylation can be used as a protein engineering tool to enhance the activity of cellulase enzymes, which are a key component in the conversion of cellulose to soluble sugars in the production of biofuels. Glycosylation is the covalent attachment of carbohydrate molecules to protein side chains, and is present in many proteins across all kingdoms of life. Moreover, glycosylation is known to serve a wide variety of functions in biological recognition, cell signaling, and metabolism. Cellulase enzymes, which are responsible for deconstructing cellulose found in plant cell walls to glucose, contain glycosylation that when modified can affect enzymatic activity-often in an unpredictable manner. To gain insight into the role of glycosylation on cellulase activity, scientists at the National Renewable Energy Laboratory (NREL) used computer simulation to predict that adding glycosylation on the carbohydrate-binding module of a cellulase enzyme dramatically boosts the binding affinity to cellulose-more than standard protein engineering approaches in which amino acids are mutated. Because it is known that higher binding affinity in cellulases leads to higher activity, this work suggests a new route to designing enhanced enzymes for biofuels production. More generally, this work suggests that tuning glycosylation in cellulase enzymes is a key factor to consider when engineering biochemical conversion processes, and that more work is needed to understand how glycosylation affects cellulase activity at the molecular level.

  6. ACL reconstruction with BPTB autograft and irradiated fresh frozen allograft

    Institute of Scientific and Technical Information of China (English)

    Kang SUN; Shao-qi TIAN; Ji-hua ZHANG; Chang-suo XIA; Cai-long ZHANG; Teng-bo YU

    2009-01-01

    Objective: To analyze the clinical outcomes of arthroscopic anterior cruciate ligament (ACL) reconstruction with irradiated bone-patellar tendon-bone (BPTB) allograft compared with non-irradiated allograft and autograft. Methods: All BPTB allografts were obtained from a single tissue bank and the irradiated allografts were sterilized with 2.5 mrad of irradiation prior to distribution. A total of 68 patients undergoing arthroscopic ACL reconstruction were prospectively randomized consecutively into one of the two groups (autograft and irradiated allograft groups). The same surgical technique was used in all operations done by the same senior surgeon. Before surgery and at the average of 31 months of follow-up (ranging from 24 to 47 months), patients were evaluated by the same observer according to objective and subjective clinical evaluations. Results: Of these patients, 65 (autograft 33, irradiated allograft 32) were available for full evaluation. When the irradiated allograft group was compared to the autografi group at the 31-month follow-up by the Lachman test, the anterior drawer test (ADT), the pivot shift test, and KT-2000 arthrometer test, statistically significant differences were found. Most importantly, 87.8% of patients in the autograft group and just only 31.3% in the irradiated allograft group had a side-to-side difference of less than 3 mm according to KT-2000. The failure rate of the ACL reconstruction with irradiated allograft (34.4%) was higher than that with autograft (6.1%). The anterior and rotational stabilities decreased significantly in the irradiated allograft group. According to the overall International Knee Docu-mentation Committee (IKDC), functional and subjective evaluations, and activity level testing, no statistically significant dif-ferences were found between the two groups. Besides, patients in the irradiated allograft group had a shorter operation time and a longer duration of postoperative fever. When the patients had a fever

  7. Interest of Polyelectrolyte Multilayer thin Films in Tissue Engineering:Application to Vascular Allograft

    Institute of Scientific and Technical Information of China (English)

    Halima KERDJOUDJ; Cedric BOURA; Vanessa MOBY; Dominique DUMAS; Luc MARCHAL; Jean-Claude VOEGEL; Jean-Fran(c)ois STOLTZ; Patrick MENU

    2005-01-01

    @@ 1 Introduction Obstructive atherosclerosis vascular disease remains one of the greatest public health threats in the world. Surgical treatment to replace diseased blood vessels is usually done using major human allografts (veins or arteries) or synthetic prosthesis ( PTFE, Dacron). However, these substitutes have not a good pateney, because of the lack of endothelial cells (ECs) layer, which prevents thrombus formation. The challenge of tissue engineering vessels is to build-up blood/substitute interface near native vessels.In order to improve ECs adhesion, it is necessary to precoat the intra-luminal vessel. Recently, a new surface modification technique arose, based on the alternate adsorption of oppositely charged polyelectrolytes. Our objective was to favour the endothelialization of the cryo-preserved allografts, treated with a thin polyelectrolyte multilayered film, made of PSS (poly (sodium-4-styrenesulfonate) ) or PAH (poly (allylamine hydrochloride) ).

  8. [Cyclosporin, toxicity and efficacy in rejection of liver allografts in the rat].

    Science.gov (United States)

    Settaf, A; Gugenheim, J; Lahlou, M K; Gigou, M; Capron-Laudereau, M; Charpentier, B; Reynes, M; Lokiec, F; Bismuth, H

    1989-01-01

    52 orthotopic liver transplants were performed in DA to lewis rat strain combination, in order to appreciate cyclosporine toxicity, and efficacy at doses of 10 mg/kg day (G II) and 20 mg/kg/day (GIII) compared to liver allografts in DA/lewis rats. The first signs of cyclosporine hepatotoxicity are biological (increased plasma level of bilirubine and transaminase) that were noticed at the dose of 20 mg/kg/day. Histological signs (cells inclusion, hepatocytic necrosis) appeared late and were less constant as well as difficult to assert creatinine plasma level was the best reflect of cyclosporine nephrotoxicity. Renal toxicity was practically constant at the dose of 20 mg/kg/day. In spite of renal and hepatic toxicity, cyclosporin by itself, allows the abolition of the acute rejection of liver allografts in the rat.

  9. Dependence of lattice strain relaxation, absorbance, and sheet resistance on thickness in textured ZnO@B transparent conductive oxide for thin-film solar cell applications

    OpenAIRE

    2016-01-01

    The interplay of surface texture, strain relaxation, absorbance, grain size, and sheet resistance in textured, boron-doped ZnO (ZnO@B), transparent conductive oxide (TCO) materials of different thicknesses used for thin film, solar cell applications is investigated. The residual strain induced by the lattice mismatch and the difference in the thermal expansion coefficient for thicker ZnO@B is relaxed, leading to an increased surface texture, stronger absorbance, larger grain size, and lower s...

  10. Reconstitution of the complete rupture in musculotendinous junction using skeletal muscle-derived multipotent stem cell sheet-pellets as a “bio-bond”

    Directory of Open Access Journals (Sweden)

    Hiroyuki Hashimoto

    2016-07-01

    Full Text Available Background. Significant and/or complete rupture in the musculotendinous junction (MTJ is a challenging lesion to treat because of the lack of reliable suture methods. Skeletal muscle-derived multipotent stem cell (Sk-MSC sheet-pellets, which are able to reconstitute peripheral nerve and muscular/vascular tissues with robust connective tissue networks, have been applied as a “bio-bond”. Methods. Sk-MSC sheet-pellets, derived from GFP transgenic-mice after 7 days of expansion culture, were detached with EDTA to maintain cell–cell connections. A completely ruptured MTJ model was prepared in the right tibialis anterior (TA of the recipient mice, and was covered with sheet-pellets. The left side was preserved as a contralateral control. The control group received the same amount of the cell-free medium. The sheet-pellet transplantation (SP group was further divided into two groups; as the short term (4–8 weeks and long term (14–18 weeks recovery group. At each time point after transplantation, tetanic tension output was measured through the electrical stimulation of the sciatic nerve. The behavior of engrafted GFP+ tissues and cells was analyzed by fluorescence immunohistochemistry. Results. The SP short term recovery group showed average 64% recovery of muscle mass, and 36% recovery of tetanic tension output relative to the contralateral side. Then, the SP long term recovery group showed increased recovery of average muscle mass (77% and tetanic tension output (49%. However, the control group showed no recovery of continuity between muscle and tendon, and demonstrated increased muscle atrophy, with coalescence to the tibia during 4–8 weeks after operation. Histological evidence also supported the above functional recovery of SP group. Engrafted Sk-MSCs primarily formed the connective tissues and muscle fibers, including nerve-vascular networks, and bridged the ruptured tendon–muscle fiber units, with differentiation into skeletal

  11. Cell sheet engineering: solvent effect on nanometric grafting of poly-N-isopropylacrylamide onto polystyrene substrate under ultraviolet radiation

    Directory of Open Access Journals (Sweden)

    Esmaeil Biazar

    2011-02-01

    potential as a biomaterial for cell sheet engineering.Keywords: nanometric grafting, solvent effect, poly-n-isopropylacrylamide, polystyrene film, ultraviolet radiation

  12. Autograft versus allograft in anterior cruciate ligament reconstruction

    Science.gov (United States)

    Kan, Shun-Li; Yuan, Zhi-Fang; Ning, Guang-Zhi; Yang, Bo; Li, Hai-Liang; Sun, Jing-Cheng; Feng, Shi-Qing

    2016-01-01

    Abstract Background: Anterior cruciate ligament (ACL) reconstruction is considered as the standard surgical procedure for the treatment of ACL tear. However, there is a crucial controversy in terms of whether to use autograft or allograft in ACL reconstruction. The purpose of this meta-analysis is to compare autograft with allograft for patients undergoing ACL reconstruction. Methods: PubMed, EMBASE, and the Cochrane Library were searched for randomized controlled trials that compared autograft with allograft in ACL reconstruction up to January 31, 2016. The relative risk or mean difference with 95% confidence interval was calculated using either a fixed- or random-effects model. The risk of bias for individual studies according to the Cochrane Handbook. The trial sequential analysis was used to test the robustness of our findings and get more conservative estimates. Results: Thirteen trials were included, involving 1636 participants. The results of this meta-analysis indicated that autograft brought about lower clinical failure, better overall International Knee Documentation Committee (IKDC) level, better pivot-shift test, better Lachman test, greater Tegner score, and better instrumented laxity test (P allograft. Autograft was not statistically different from allograft in Lysholm score, subjective IKDC score, and Daniel 1-leg hop test (P > 0.05). Subgroup analyses demonstrated that autograft was superior to irradiated allograft for patients undergoing ACL reconstruction in clinical failure, Lysholm score, pivot-shift test, Lachman test, Tegner score, instrumented laxity test, and subjective IKDC score (P allograft. Conclusions: Autograft is superior to irradiated allograft for patients undergoing ACL reconstruction concerning knee function and laxity, but there are no significant differences between autograft and nonirradiated allograft. However, our results should be interpreted with caution, because the blinding methods were not well used. PMID

  13. Percutaneous fusion of lumbar facet with bone allograft

    Directory of Open Access Journals (Sweden)

    Félix Dolorit Verdecia

    2015-03-01

    Full Text Available OBJECTIVE: To assess the evolution of the cases treated with percutaneous facet fusion with bone allograft in lumbar facet disease. METHOD: Between 2010 and 2014, 100 patients (59 women and 41 men diagnosed with lumbar facet disease underwent surgery. RESULTS: The lumbar facet fusion with bone allograft shows good clinical results, is performed on an outpatient basis, and presents minimal complications and rapid incorporation of the patient to the activities of daily living. CONCLUSIONS: The lumbar facet fusion with bone allograft appears to be an effective treatment for lumbar facet disease.

  14. High-pressure saline washing of allografts reduces bacterial contamination.

    Science.gov (United States)

    Hirn, M Y; Salmela, P M; Vuento, R E

    2001-02-01

    60 fresh-frozen bone allografts were contaminated on the operating room floor. No bacterial growth was detected in 5 of them after contamination. The remaining 55 grafts had positive bacterial cultures and were processed with three methods: soaking in saline, soaking in antibiotic solution or washing by high-pressure saline. After high-pressure lavage, the cultures were negative in three fourths of the contaminated allografts. The corresponding figures after soaking grafts in saline and antibiotic solution were one tenth and two tenths, respectively. High-pressure saline cleansing of allografts can be recommended because it improves safety by reducing the superficial bacterial bioburden.

  15. C4d immunoreactivity of intraoperative zero-hour biopsy in renal allograft.

    Science.gov (United States)

    Lee, C; Park, J H; Suh, J H; Kim, H W; Moon, K C

    2014-12-01

    C4d deposition in the peritubular capillaries is known to be correlated with antibody-mediated rejection (AMR) in renal allografts. An intraoperative zero-hour biopsy during transplantation is considered an indicator to indirectly determine the status of the donor kidney. In this study, we investigated the relationship between C4d immunoreactivity of intraoperative zero-hour biopsy in renal allograft, thought to be due to donor condition, and acute rejection episodes during follow-up. We collected 147 renal transplantation cases examining intraoperative zero-hour biopsy with C4d immunohistochemical staining. All cases were from the Seoul National University Hospital between 2010 and 2011. Of the 147 cases, 24 (16.3%) showed strong C4d staining in the glomeruli, 38 (25.9%) showed weak staining, and the remainder (57.8%) showed negative staining. Nine cases (6.1%) showed positive C4d staining in the arterioles, and the remainder (93.9%) were negative. There were no significant differences between acute T-cell-mediated rejection and acute AMR episodes in the renal allograft specimens during follow-up according to the glomerular or arteriolar C4d immunoreactivity of the intraoperative zero-hour biopsy specimens.

  16. IL-17与Th17细胞在小鼠心脏移植急性排斥反应中的作用%Effect of interleukin-17 and T helper cell 17 on acute heart allograft rejection in mice

    Institute of Scientific and Technical Information of China (English)

    司中洲; 吴建国; 贺志军; 李亭

    2011-01-01

    Objective To investigate the role of T helper cell 17 (Thl 7 ) cells and their cytokines IL-17 in heart allograft rejection in mice.Methods The heart transplantation models were randomly divided into 2 groups: a allograft group (n = 12) and an isograft group (n = 12).On the post-operative day (POD) 3 and 7, serum IL-17 level was tested by enzyme-linked immunosorbent assay, and Th17 cells in heart grafts were measured by flow cytometry.The heart grafts were harvested and saved in 10% formalin, and then embedded in paraffin.Results Compared with the isograft group, the allograft group had a higher serum level of IL-17 on POD3 and POD7 (P <0.05),and the level of IL-17 was higher on POD7 than that on POD3 (P <0.05 ).The allograft group had more Th17 cells infiltrating in grafts on POD3 and POD7 (P < 0.05 ) and there were more Th17 cells infiltrating on POD7 than that on POD3 (P < 0.05 ).Histological examination showed that the prolongation of post transplantation time resulted in more rejection pathological changes.Conclusion Th17 cells may play an important role in the development of heart transplant rejection.IL-17 may serve as a predictive parameter for allograft rejection in the future.%目的:研究辅助T细胞17(T helper cell 17,Th17)细胞及其相关因子白细胞介素17(interleukin-17,IL-17)在小鼠心脏移植排斥反应中的表达及意义.方法:建立小鼠心脏移植模型,实验动物随机分为急性排斥反应组(n=12)和同系移植组(n=12),应用酶联免疫吸附实验(enzyme-linked immunosorbent assay,ELISA)分别检测2组小鼠移植术后第3天和第7天血清中IL-17的含量;应用流式细胞技术检测移植心脏中浸润淋巴细胞中Th17细胞数量,并取移植心脏经10%甲醛固定后行常规病理检查.结果:急性排斥反应组术后第3天及第7天血清中IL-17表达明显高于同系移植组(P<0.05),且急性排斥反应组术后第7天IL-17表达明显高于第3天(P<0.05);与同系移植组相比,

  17. Adenoviral-mediated localized CTLA-4Ig gene expression induces long-term allograft pancreas survival and donor-specific immune tolerance in rats

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    T cell activation following alloantigen recognition plays a critical role in the development of the rejection in all solid organ, tissue and cell transplantation. A recombinant molecule, cytotoxic T lymphocyte antigen 4 antibody (CTLA-4Ig), is known to induce to T-cell into "anergy" by blocking the costimulatory B7-CD28 interaction. Either systemic or localized administration of CTLA-Ig has been shown to prolong allograft survival and induce donor-specific tolerance in some transplant models. In this study, we characterized the expression and immunosuppressive effectiveness of adenoviral-mediated CTLA-4Ig gene transfer. We demonstrated transduction of the allografts with AdCTLA-41g resulted in localized expression, permanent graft survival and stable donor-specific tolerance. In addition, by performing simultaneous dual-organ transplantation, we targeted on immunosuppression through a local expression of CTLA-4Ig via adenoviral-mediated gene transfer into pancreatic allografts.

  18. Comparison between cryopreserved and glycerol-preserved allografts in a partial-thickness porcine wound model.

    Science.gov (United States)

    Yoon, Cheonjae; Lim, Kihwan; Lee, Sungjun; Choi, Yanghwan; Choi, Youngwhan; Lee, Jungsuk

    2016-03-01

    Human skin allografts are one of the best temporary biological coverings for severely burned patients. Cryopreserved (CPA) and glycerol-preserved (GPA) allografts are the most widely used types. This study compared the allograft efficiency of both preservation methods under the same conditions. To simulate actual clinical conditions, we used a porcine wound model. In addition, we evaluated the macroscopic and microscopic scoring of graft performance for each method. Porcine cadaver skin 1 mm thick was obtained from one pig. Cryopreserved skin cell viability was 20.8 %, glycerol-preserved skin was 9.08 %, and fresh skin was 58.6 %. We made ten partial-thickness wounds each in two pigs. The take rates on day 2 were 96.23 and 82.65 % in the GPA and CPA group (both n = 9), respectively. After 1 week, the take rates of both groups were nearly equal. The removal rate at week 5 was 98.87 and 94.41 % in the GPA and CPA group, respectively. On microscopic findings at week 2, inflammation was greater in the CPA group. Other findings such as fibroblast hyperplasia and neovascularization were not significantly different between both groups. At week 5, the score of collagen fiber synthesis was 2.67 ± 0.47 and 2.33 ± 0.47 in the GPA and CPA group, respectively. The epidermal-dermal junction was 2.22 ± 0.79 and 2.00 ± 0.47 in the GPA and CPA group, respectively. These findings suggest that wound healing takes longer in the CPA group. The preservation method of allografts is not a absolute factor in the wound healing process in this wound model.

  19. Tissue-culture light sheet fluorescence microscopy (TC-LSFM) allows long-term imaging of three-dimensional cell cultures under controlled conditions.

    Science.gov (United States)

    Pampaloni, Francesco; Berge, Ulrich; Marmaras, Anastasios; Horvath, Peter; Kroschewski, Ruth; Stelzer, Ernst H K

    2014-10-01

    Fluorescence long-term imaging of cellular processes in three-dimensional cultures requires the control of media supply, temperature, and pH, as well as minimal photodamage. We describe a system based on a light sheet fluorescence microscope (LSFM), which is optimized for long-term, multi-position imaging of three-dimensional in-gel cell cultures. The system integrates a stable culture condition control system in the optical path of the light-sheet microscope. A further essential element is a biocompatible agarose container suitable for the LSFM, in which any cell type can be cultured in different gel matrices. The TC-LSFM allows studying any in vitro cultured cell type reacting to, dividing in, or migrating through a three-dimensional extracellular matrix (ECM) gel. For this reason we called it "tissue culture-LSFM" (TC-LSFM). The TC-LSFM system allows fast imaging at multiple locations within a millimeter-sized ECM gel. This increases the number of analyzed events and allows testing population effects. As an example, we show the maturation of a cyst of MDCK (canine kidney epithelial) cells over a period of three days. Moreover, we imaged, tracked, and analyzed MDCK cells during the first five days of cell aggregate formation and discovered a remarkable heterogeneity in cell cycle lengths and an interesting cell death pattern. Thus, TC-LSFM allows performing new long-term assays assessing cellular behavior in three-dimensional ECM-gel cultures. For example migration, invasion or differentiation in epithelial cell systems, stem cells, as well as cancer cells can be investigated.

  20. Renalase Gene Polymorphism in Patients After Renal Allograft Transplantation

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    Andrzej Pawlik

    2014-06-01

    Full Text Available Background/Aims: Renalase is a recently discovered protein, which is likely involved in regulation of blood pressure in humans and animals. Previous studies suggest that renalase reflects kidney functioning. A common missense polymorphism in the flavin-adenine dinucleotide-binding domain of human renalase (Glu37Asp has been described. In this study we examined the association between (Glu37Asp polymorphism (rs2296545 in renalase gene and kidney allograft function. Methods: The study enrolled 270 Caucasian kidney allograft recipients. SNP within the renalase was genotyped using TaqMan genotyping assays. Results: There were no statistically significant associations between renalase gene rs2296545 polymorphism and delayed graft function, acute rejection, chronic allograft dysfunction as well as creatinine serum concentrations and blood pressure values after transplantation. Conclusions: The results of this study suggest, that renalase gene rs2296545 polymorphism is not important factor determining renal allograft function.

  1. Multifocal bacterial osteomyelitis in a renal allograft recipient following urosepsis.

    Science.gov (United States)

    Valson, A T; David, V G; Balaji, V; John, G T

    2014-05-01

    Non-tubercular bacterial osteomyelitis is a rare infection. We report on a renal allograft recipient with osteomyelitis complicating urosepsis, manifesting as a multifocal infection poorly responsive to appropriate antibiotics and surgical intervention and culminating in graft loss.

  2. 阻断ICOS/B7h信号的供体特异性输血对移植受体CD4+CD25+调节性T细胞的影响%Influence of donor specific transfusion with impaired ICOS/B7h allorecognition on CD4 + CD25+regulatory T cells of cardiac allograft recipient

    Institute of Scientific and Technical Information of China (English)

    杜峻峰; 李世拥; 于波; 白雪; 左富义

    2010-01-01

    目的 观察阻断ICOS/B7h信号的供体特异性输血(DST)对异基因小鼠心脏移植术后体内CD4+CD25+调节性T细胞(Treg)的影响.方法 按陈氏方法建立小鼠颈部异位心脏移植模型,实验分3组,异基因组及同基因组:供心分别来源于BALB/C和C57BL/6小鼠,受体均为C57BL/6小鼠,未予治疗.治疗组:移植当天给予受体鼠(C57BL/6)尾静脉注射5×106 ICOS-Fc靶定的供体(BALB/C)脾B淋巴细胞,d0~6连续给予受体鼠尾静脉注射ICOS-Fc 200 μg/d.术后统计各组移植物的存活时间,通过流式细胞术检测受体鼠外周血中CD4+CD25+Treg的亚群比例,利用逆转录-聚合酶链反应(RT-PCR)检测移植物中FOXP3的mRNA表达,在混合淋巴细胞反应中检测CD4+CD25+Treg对CD4+CD25-效应T细胞(Teff)的增殖抑制效率.结果 与异基因组比较,治疗组心脏移植物存活时间明显延长[(84.38±29.14)d比(7.00±0.76)d,P<0.01].各组中,治疗组受体外周血中CD4+CD25+Treg亚群比例显著上调[(15.60±5.69)%,P<0.01].与其他两组比较,治疗组心脏移植物中FOXP3 mRNA表达显著上调.以正常鼠为对照,耐受鼠脾脏中获取的CD4+CD25+Treg能够更高效地抑制CD4+CD25-Teff在混合淋巴细胞培养中的增殖效应.结论 通过阻断ICOS/B7h信号的DST可以诱导异基因小鼠心脏移植耐受,CD4+CD25+Treg在耐受的形成与维持中均起着重要作用.%Objective To investigate the possibility of CD4+CD25+ regulatory T cells (Treg) enhancement, which induced by donor specific transfusion combined with blockade of ICOS/B7h costimulation following an allogenic murine heterotopic cardiac transplantation. Methods Recipient mice were assigned to 3 groups. In allogenic group, donor hearts were harvested from BALB/C mice, and allografts were heterotopically transplanted in the neck of C57BL/6 using Chen' s technique, without treatment. In isogeneic group, donor hearts were harvested from C57BL/6 mice, and isografts were heterotopically

  3. Cardiac allograft immune activation: current perspectives

    Directory of Open Access Journals (Sweden)

    Chang D

    2014-12-01

    Full Text Available David Chang, Jon Kobashigawa Cedars-Sinai Heart Institute, Los Angeles, CA, USA Abstract: Heart transplant remains the most durable option for end-stage heart disease. Cardiac allograft immune activation and heart transplant rejection remain among the main complications limiting graft and recipient survival. Mediators of the immune system can cause different forms of rejection post-heart transplant. Types of heart transplant rejection include hyperacute rejection, cellular rejection, antibody-mediated rejection, and chronic rejection. In this review, we will summarize the innate and adaptive immune responses which influence the post-heart transplant recipient. Different forms of rejection and their clinical presentation, detection, and immune monitoring will be discussed. Treatment of heart transplant rejection will be examined. We will discuss potential treatment strategies for preventing rejection post-transplant in immunologically high-risk patients with antibody sensitization. Keywords: heart transplant, innate immunity, adaptive immunity, rejection, immunosuppression

  4. Influence of dendritic cells modified with costimulatory blocker cytotoxic T lymphocyte associated antigen-4 immunoglobulin on the survival of renal allografts%共刺激阻断剂细胞毒性T淋巴细胞相关抗原4Ig基因修饰树突状细胞对移植肾存活的影响

    Institute of Scientific and Technical Information of China (English)

    黄赤兵; 李健; 张艮甫; 范明齐; 王琦

    2008-01-01

    BACKGROUND: Previous studies showed that donor systemic injection of B7/CD28 costimulatory blocker cytotoxic T lymphocyte associated antigen 4 immunoglobulin (CTLA-4Ig) needed in T cell activation can markedly prolong the survival time of rat renal allografts, which, however, has limitations, such as high dose, extensive influence, poor specificity, systemic adverse reactions.OBJECTIVE: In order to improve the targeting of CTLA-4Ig, we modified the dendritic cells of donors and recipients in vitro with CTLA- 4Ig and observed the influence of two kinds of dendritic cells applied alone or together on the survival of renal allografis in rats.DESIGN, TIME AND SETTING: The randomized controlled animal experiment was performed between April 2003 and July 2004 at Laboratory of Department of Urinary Surgery, Xinqiao Hospital, the Third Military Medical University, Chongqing, China.MATERIALS: Kidney donor: inbred Brown-Norway rats, kidney recipient: inbred Lewis rats, unrelated lymphocyte donor: Wistar rats.METHODS: Bone marrow derived dendritic cells of Lewis and Brown Norway rats were modified with CTLA- 4Ig gene recombinant adenovirus in vitro. Animal models of kidney transplantation were built with Brown Norway rats as donors while Lewis rats as recipients. The modified dendritic cells were injected into Lewis rats through femoral vein 24 hours before kidney transplantation alone (group 1 (n=8), donor dendritic cells; group 2 (n=8), recipient dendritic cells) and in combination (group 3 (n=8), donor and recipient dendritic cells). While the recipients without injection were used as control (group 4 (n=6)).MAIN OUTCOME MEASURES: Survival time of renal allografts; the reaction degrees of splenocytes to donor and unrelated antigen determined by MTT method on day 20 postoperation.RESULTS: Survival time of renal allografts in group 2 was not prolonged compared with group 4 while the survival time was markedly prolonged in group 3 (P < 0.01). The response of rat splenocytes

  5. Late de novo minimal change disease in a renal allograft

    OpenAIRE

    Madhan Krishan; Temple-Camp Cynric

    2009-01-01

    Among the causes of the nephrotic syndrome in renal allografts, minimal change disease is a rarity with only few cases described in the medical literature. Most cases described have occurred early in the post-transplant course. There is no established treatment for the condition but prognosis is favorable. We describe a case of minimal change disease that developed 8 years after a successful transplantation of a renal allograft in a middle-aged woman. The nephrotic syndrome was accompanied by...

  6. Deceased donor skin allograft banking: Response and utilization

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    Gore Madhuri

    2010-10-01

    Full Text Available Background: In the absence of xenograft and biosynthetic skin substitutes, deceased donor skin allografts is a feasible option for saving life of patient with extensive burn injury in our country. Aims: The first deceased donor skin allograft bank in India became functional at Lokmanya Tilak Municipal (LTM medical college and hospital on 24 th April 2000. The response of Indian society to this new concept of skin donation after death and the pattern of utilization of banked allografts from 2000 to 2010 has been presented in this study. Settings and Design: This allograft skin bank was established by the department of surgery. The departments of surgery and microbiology share the responsibility of smooth functioning of the bank. Materials and Methods: The response in terms of number of donations and the profile of donors was analyzed from records. Pattern and outcome of allograft utilization was studied from specially designed forms. Results: During these ten years, 262 deceased donor skin allograft donations were received. The response showed significant improvement after counselling was extended to the community. Majority of the donors were above 70 years of age and procurement was done at home for most. Skin allografts from 249 donors were used for 165 patients in ten years. The outcome was encouraging with seven deaths in 151 recipients with burn injuries. Conclusions: Our experience shows that the Indian society is ready to accept the concept of skin donation after death. Use of skin allografts is life saving for large burns. We need to prepare guidelines for the establishment of more skin banks in the country.

  7. THE DIAGNOSIS OF LIVER ALLOGRAFT ACUTE REJECTION IN LIVER BIOPSIES

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    L. V. Shkalova

    2011-01-01

    Full Text Available We performed histological examination of 80 liver allograft biopsies, the diagnosis of acute rejection was proved in 34 cases. Histological changes in liver biopsies in different grades of acute rejection were estimated according to Banff classification 1995, 1997 and were compared with current literature data. The article deals with the question of morphological value of grading acute rejection on early and late, also we analyze changes in treat- ment tactics after morphological verification of liver allograft acute rejection. 

  8. Cortical and medullary vascularity in renal allograft biopsies

    OpenAIRE

    2012-01-01

    Aim: To evaluate the relation between cortical and medullary peritubular capillaries (PTCs) and scarring. There are presently no studies about medullary PTCs in renal allograft biopsies. Materials and methods: Nonprotocol allograft biopsies were evaluated and 41 with adequate medullary and cortical tissues were selected. Vascular structures were counted separately at the medulla and cortex on anti-CD34 stained sections. Other histopathological and clinical findings were retrieved from the p...

  9. De Novo Collapsing Glomerulopathy in a Renal Allograft Recipient

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    Kanodia K

    2008-01-01

    Full Text Available Collapsing glomerulopathy (CG, characterized histologically by segmental/global glomerular capillary collapse, podocyte hypertrophy and hypercellularity and tubulo-interstitial injury; is characterized clinically by massive proteinuria and rapid progressive renal failure. CG is known to recur in renal allograft and rarely de novo. We report de novo CG 3 years post-transplant in a patient who received renal allograft from haplo-identical type donor.

  10. The protective effects on the renal allografts from brain dead donor rats pretreated with bone marrow mesenchymal stem cells%骨髓间充质干细胞预处理脑死亡供鼠对移植肾的保护作用

    Institute of Scientific and Technical Information of China (English)

    陈洁; 张智; 曾慧兰; 苏泽轩; 余钧雷; 吴永璐; 袁博翔

    2015-01-01

    Objective To investigate the protective effects on the renal allografts from brain dead (BD) donor rats pretreated with bone marrow mesenchymal stem cells (MSCs).Method Three groups [normal transplant group (G1).BD transplant group (G2),and MSCs pretreated + BD transplant group (G3)] were set up.Male F344 rats served as donors and male Lewis rats as recipients.In G1,kidneys from F344 donor rats were implanted into Lewis recipients.In G2,kidneys from F344 BD donor rats were engrafted into Lewis recipients.In G3,after BD was established in F344 rats,MSCs were given intravenously to the rats.The kidneys harvested 6 h later were transplanted to Lewis recipients.Cyclosporine was intromuscularly given daily to the recipient rats for 10 days.Right kidneys were resected from recipients on day 10.Creatinine level was examined on day 14,21,28,and 35.Renal allografts harvested on day 35 were pathologically detected.The irnmunochemistry expression of interleukin (IL)-1β and tumor necrotic factor (TNF)-α in renal allograft tissue was tested.Result Serum creatinine levels in G2 were remarkably higher than those in G1 and G3 (P<0.01) on day 14,21,28,and 35 postoperatively.The creatinine levels on the above mentioned time points had no statistically significant difference between G3 and G1 except on day 21.Postoperative pathological changes in G2 of both pronounced infiltration of mononuclear cells and tubular epithelia[inflammation were notably increased in renal allografts as compared with those in G1 and G3.There was no obvious difference between G1 and G3 in infiltrated mononuclear cells and tubular epithelial inflammation.Positive expression levels of both IL-1β and TNF-α in glomerular,tubular and interstitial epithelial cells were statistically enhanced in G2 as compared with those in G1 and G3 (H =7.210,P =0.027),while there was no statistically significant difference in the expression of both IL-1[β and TNF-α between G1 and G3.Conclusion Brain dead donor rats

  11. Articular Cartilage Repair Using Marrow Stimulation Augmented with a Viable Chondral Allograft: 9-Month Postoperative Histological Evaluation

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    James K. Hoffman

    2015-01-01

    Full Text Available Marrow stimulation is frequently employed to treat focal chondral defects of the knee. However, marrow stimulation typically results in fibrocartilage repair tissue rather than healthy hyaline cartilage, which, over time, predisposes the repair to failure. Recently, a cryopreserved viable chondral allograft was developed to augment marrow stimulation. The chondral allograft is comprised of native viable chondrocytes, chondrogenic growth factors, and extracellular matrix proteins within the superficial, transitional, and radial zones of hyaline cartilage. Therefore, host mesenchymal stem cells that infiltrate the graft from the underlying bone marrow following marrow stimulation are provided with the optimal microenvironment to undergo chondrogenesis. The present report describes treatment of a trochlear defect with marrow stimulation augmented with this novel chondral allograft, along with nine month postoperative histological results. At nine months, the patient demonstrated complete resolution of pain and improvement in function, and the repair tissue consisted of 85% hyaline cartilage. For comparison, a biopsy obtained from a patient 8.2 months after treatment with marrow stimulation alone contained only 5% hyaline cartilage. These outcomes suggest that augmenting marrow stimulation with the viable chondral allograft can eliminate pain and improve outcomes, compared with marrow stimulation alone.

  12. Proximal femur reconstruction by an allograft prosthesis composite.

    Science.gov (United States)

    Donati, Davide; Giacomini, Stefano; Gozzi, Enrico; Mercuri, Mario

    2002-01-01

    Twenty-seven patients who had resection of the proximal femur for bone tumors and reconstruction with an allograft prosthesis composite are reported. In most of the patients, the prosthesis was a long-stem revision type, cemented in the allograft and uncemented in the femoral shaft. The abductor muscles and iliopsoas were sutured to the corresponding tendons on the allograft. Implant-related complications and functional results were evaluated and are reported. Twenty-two patients achieved a minimum followup of 36 months (range, 36-126 months; average, 58 months). The implant was removed in two patients (one for infection, one for intraoperative fracture of the allograft). One patient experienced nonunion, whereas in the remaining 24 patients, the allograft eventually united to the host bone. A frequent late complication (17 patients) was fracture of the greater trochanter of the allograft. In the whole series, only four new operations were done for implant-related complications. In 22 patients who could be evaluated, the functional evaluation according to the Musculoskeletal Tumor Society System was excellent in 16 (73%) patients, good in four (18%), and fair in two (9%). These results compare favorably with those of megaprostheses for tumor resection of the proximal femur, where a Trendelenburg gait almost always is present.

  13. Clinical and functional outcomes of tibial intercalary allograft reconstructions

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    Lucas López Millán

    2012-12-01

    Full Text Available Background The purpose of this study was to evaluate the survival, the complications and the functional outcome of intercalary tibial allografts reconstructions following tumor resections. Methods Intercalary tibia segmental allografts were implanted in 26 consecutive patients after segmental resections. Average follow-up was 6 years. Allograft survival was determined with the Kaplan-Meier method. Function was evaluated with the Musculoskeletal Tumor Society scoring system (MSTS. Results The rate of survival was 84% (CI 95%: 90%- 70% at 5 years and 79% at 10 years (CI 95%: 95%-63%. Allografts were removed in 5 patients (3 due to infections and 2 due to local recurrences. Two patients showed diaphyseal nonunion and 3 had an incomplete fracture, but it was not necessary to remove the allografts. Average MSTS functional score was 29 points (range 27 to 30. Conclusions Despite the incidence of complications, this analysis showed an acceptable survival with excellent functional scores. The use of intercalary allograft clearly has a place in the reconstruction of a segmental defect created by the resection of a tumor in the diaphyseal and/or metaphyseal portion of the tibia.

  14. The use of a biostatic fascia lata thigh allograft as a scaffold for autologous human culture of fibroblasts--An in vitro study.

    Science.gov (United States)

    Żurek, Jarek; Dominiak, Marzena; Botzenhart, Ute; Bednarz, Wojciech

    2015-05-01

    The method for covering gingival recession defects and augmenting keratinized gingiva involves the use of autogenuous connective tissue grafts obtained from palatal mucosa in combination with various techniques of flap repositioning or tunnel techniques. In the case of multiple gingival recession defects the amount of connective tissue available for grafting is insufficient. Therefore, the use of substitutes is necessary. The most widely used material in recent years has been the acellular dermal matrix allograft. The disadvantage of its application lies in the absence of cells and blood vessels, which increases incorporation time. Primary cultured human autologic fibroblasts are commonly used to optimize the healing process. The aim of this study was to examine the in vitro biocompatibility of human fascia lata allograft as a new scaffold for primary cultured human autologic fibroblasts. For that, a fibroblast culture obtained from a fragment of gingival tissue taken from the hard palate mucosa of a subject was used. After 14 days the colony cells were inoculated on a fragment of human fascia lata allograft. After a further 7 days of incubation the material was frozen, cut and prepared for histochemical examination. After two weeks of incubation, and 7 days after inoculation on a fragment of fascia lata allograft numerous accumulations of the cultured fibroblast were found that had a typical structure and produced collagen fibres. A human fascia lata allograft can be used as a scaffold for primary cultured human autologic fibroblasts. Further studies should confirm the clinical efficacy of this solution.

  15. Pathological characteristics of liver allografts from donation after brain death followed by cardiac death in pigs.

    Science.gov (United States)

    Ye, Hui; Wang, Dong-Ping; Zhang, Chuan-Zhao; Zhang, Long-Juan; Wang, Hao-Chen; Li, Zhuo-Hui; Chen, Zhen; Zhang, Tao; Cai, Chang-Jie; Ju, Wei-Qiang; Ma, Yi; Guo, Zhi-Yong; He, Xiao-Shun

    2014-10-01

    Donation after brain death followed by circulatory death (DBCD) is a unique practice in China. The aim of this study was to define the pathologic characteristics of DBCD liver allografts in a porcine model. Fifteen male pigs (25-30 kg) were allocated randomly into donation after brain death (DBD), donation after circulatory death (DCD) and DBCD groups. Brain death was induced by augmenting intracranial pressure. Circulatory death was induced by withdrawal of life support in DBCD group and by venous injection of 40 mL 10% potassium chloride in DCD group. The donor livers were perfused in situ and kept in cold storage for 4 h. Liver tissue and common bile duct samples were collected for hematoxylin and eosin staining, TUNEL testing and electron microscopic examination. Spot necrosis was found in hepatic parenchyma of DBD and DBCD groups, while a large area of necrosis was shown in DCD group. The apoptosis rate of hepatocytes in DBD [(0.56±0.30)%] and DBCD [(0.50 ± 0.11)%] groups was much lower than that in DCD group [(3.78±0.33)%] (P0.05)). The structures of bile duct were intact in both DBD and DBCD groups, while the biliary epithelium was totally damaged in DCD group. Under electron microscope, the DBD hepatocytes were characterized by intact cell membrane, well-organized endoplasmic reticulum, mild mitochondria edema and abundant glycogens. Broken cell membrane, mild inflammatory cell infiltration and sinusoidal epithelium edema, as well as reduced glycogen volume, were found in the DBCD hepatocytes. The DCD hepatocytes had more profound cell organelle injury and much less glycogen storage. In conclusion, the preservation injury of DBCD liver allografts is much less severe than that of un-controlled DCD, but more severe than that of DBD liver allografts under electron microscope, which might reflect post-transplant liver function to some extent.

  16. Quadriceps tendon allografts as an alternative to Achilles tendon allografts: a biomechanical comparison.

    Science.gov (United States)

    Mabe, Isaac; Hunter, Shawn

    2014-12-01

    Quadriceps tendon with a patellar bone block may be a viable alternative to Achilles tendon for anterior cruciate ligament reconstruction (ACL-R) if it is, at a minimum, a biomechanically equivalent graft. The objective of this study was to directly compare the biomechanical properties of quadriceps tendon and Achilles tendon allografts. Quadriceps and Achilles tendon pairs from nine research-consented donors were tested. All specimens were processed to reduce bioburden and terminally sterilized by gamma irradiation. Specimens were subjected to a three phase uniaxial tension test performed in a custom environmental chamber to maintain the specimens at a physiologic temperature (37 ± 2 °C) and misted with a 0.9 % NaCl solution. There were no statistical differences in seven of eight structural and mechanical between the two tendon types. Quadriceps tendons exhibited a significantly higher displacement at maximum load and significantly lower stiffness than Achilles tendons. The results of this study indicated a biomechanical equivalence of aseptically processed, terminally sterilized quadriceps tendon grafts with bone block to Achilles tendon grafts with bone block. The significantly higher displacement at maximum load, and lower stiffness observed for quadriceps tendons may be related to the failure mode. Achilles tendons had a higher bone avulsion rate than quadriceps tendons (86 % compared to 12 %, respectively). This was likely due to observed differences in bone block density between the two tendon types. This research supports the use of quadriceps tendon allografts in lieu of Achilles tendon allografts for ACL-R.

  17. Long-term histopathology of allografts in sensitized kidney recipients.

    Science.gov (United States)

    Miura, Masayoshi; Harada, Hiroshi; Fukasawa, Yuichiro; Hotta, Kiyohiko; Itoh, Yosuke; Tamaki, Tohru

    2012-07-01

    Successful desensitization therapy has brought satisfying short-term outcomes in the recipients with anti-donor antibody. We analyzed the long-term pathology of the allografts in the sensitized kidney recipients. Eleven stable recipients after desensitization against positive flow cytometry T-cell crossmatch (FTXM) were included. They were divided into two groups, based on the protocol biopsies findings at three to eight yr (group 1: subclinical glomerulitis and/or peritubular capillaritis, n = 5 and group 2: no rejection, n = 6). Estimated glomerular filtration rate (eGFR), presence of donor-specific antibody (DSA), mean channel shift (MCS) of FTXM, urine protein levels, acute antibody-mediated rejection (AAMR) episodes, and protocol biopsy findings were compared. Chronic transplant glomerulopathy was found in final biopsy of all group 1 cases. DSA was positive in 60% but C4d was positive in 20% case of the group 1. The history of AAMR was only found in the group 1. There was no difference in eGFR decline or proteinuria. The MCS of FTXM was higher in the group 1. The recipients with AAMR history, high MCS in FTXM, and subclinical microvascular inflammation in the early protocol biopsies have risk for developing chronic rejection in long term.

  18. Effect of blood transfusions on canine renal allograft survival

    Energy Technology Data Exchange (ETDEWEB)

    Van Der Linden, C.J.; Buurman, W.A.; Vegt, P.A.; Greep, J.M.; Jeekel, J.

    1982-04-01

    In this study significantly prolonged canine renal allograft survival has been demonstrated after transfusion of 100 ml of third-party whole blood given peroperatively. Peroperative transfusions of third-party leukocyte-free blood or pure lymphocyte cell suspensions did not influence graft survival. Futhermore, no improvement in graft survival has been found after a peroperative transfuson of irradiated whole blood (2500 rad). These data suggest that delayed graft rejection after blood transfusions can only be expected after the administration of whole blood. The role of competent lymphocytes in whole blood is questionable, since a transfusion of irradiated whole blood in combination with nonirradiated lymphocytes did not lead to prolonged graft survival. Immunosuppression of the recipient directly after transfusion seems to be essential to induce the beneficial effect of blood transfusions. This has been demonstrated for a transfusion of whole blood 14 days before transplantation. A single transfusion of 100 ml of whole blood 14 days before transplantation could effectively prolong graft survival if immunosuppression with azathioprine and prednisone was started on the day of transfusion. No improvement in graft survival has been found with such a transfusion if preoperative immunosuppression has been omitted.

  19. Effect of blood transfusions on canine renal allograft survival

    Energy Technology Data Exchange (ETDEWEB)

    van der Linden, C.J.; Buurman, W.A.; Vegt, P.A.; Greep, J.M.; Jeekel, J.

    1982-04-01

    In this study significantly prolonged canine renal allograft survival has been demonstrated after transfusion of 100 ml of third-party whole blood given peroperatively. Peroperative transfusions of third-party leukocyte-free blood or pure lymphocyte cell suspensions did not influence graft survival. Furthermore, no improvement in graft survival has been found after a peroperative transfusion of irradiated whole blood (2500 rad). These data suggest that delayed graft rejection after blood transfusions can only be expected after the administration of whole blood. The role of competent lymphocytes in whole blood is questionable, since a transfusion or irradiated whole blood in combination with nonirradiated lymphocytes did not lead to prolonged graft survival. Immunosuppression of the recipient directly after transfusion seems to be essential to induce the beneficial effect of blood transfusions. This has been demonstrated for a transfusion of whole blood 14 days before transplantation. A single transfusion of 100 ml of whole blood 14 days before transplantation could effectively prolong graft survival if immunosuppression with azathioprine and prednisone was started on the day of transfusion. No improvement in graft survival has been found with such a transfusion if preoperative immunosuppression has been omitted.

  20. Uncemented allograft-prosthetic composite reconstruction of the proximal femur

    Directory of Open Access Journals (Sweden)

    Li Min

    2014-01-01

    Full Text Available Background: Allograft-prosthetic composite can be divided into three groups names cemented, uncemented, and partially cemented. Previous studies have mainly reported outcomes in cemented and partially cemented allograft-prosthetic composites, but have rarely focused on the uncemented allograft-prosthetic composites. The objectives of our study were to describe a surgical technique for using proximal femoral uncemented allograft-prosthetic composite and to present the radiographic and clinical results. Materials and Methods: Twelve patients who underwent uncemented allograft-prosthetic composite reconstruction of the proximal femur after bone tumor resection were retrospectively evaluated at an average followup of 24.0 months. Clinical records and radiographs were evaluated. Results: In our series, union occurred in all the patients (100%; range 5-9 months. Until the most recent followup, there were no cases with infection, nonunion of the greater trochanter, junctional bone resorption, dislocation, allergic reaction, wear of acetabulum socket, recurrence, and metastasis. But there were three periprosthetic fractures which were fixed using cerclage wire during surgery. Five cases had bone resorption in and around the greater trochanter. The average Musculoskeletal Tumor Society (MSTS score and Harris hip score (HHS were 26.2 points (range 24-29 points and 80.6 points (range 66.2-92.7 points, respectively. Conclusions: These results showed that uncemented allograft-prosthetic composite could promote bone union through compression at the host-allograft junction and is a good choice for proximal femoral resection. Although this technology has its own merits, long term outcomes are yet not validated.

  1. Coralline hydroxyapatite granules inferior to morselized allograft around uncemented porous Ti implants: unchanged fixation by addition of concentrated autologous bone marrow aspirate.

    Science.gov (United States)

    Baas, Jorgen; Svaneby, Dea; Jensen, Thomas Bo; Elmengaard, Brian; Bechtold, Joan; Soballe, Kjeld

    2011-10-01

    We compared early fixation of titanium implants grafted with impacted allograft bone or coralline hydroxyapatite (HA) granules (Pro Osteon 200) with and without the addition of concentrated bone marrow cells (BMC). Autologous bone marrow aspirate was centrifuged to increase the BMC concentration. Four nonloaded cylindrical, porous coated titanium implants with a circumferential gap of 2.3 mm were inserted in the proximal humeri of eight dogs. Coralline HA granules +/- BMC were impacted around the two implants on one side, and allograft +/- BMC was impacted around the contra lateral implants. Observation time was 4 weeks. The implants surrounded by allograft bone had a three-fold better fixation than the HA-grafted implants. The concentration of BMC after centrifugation was increased with a factor 2.1. The addition of BMC to either of the bone graft materials had no statistically significant effects on implant fixation. The allografted implants were well osseointegrated, whereas the HA-grafted implants were largely encapsulated in fibrous tissue. The addition of concentrated autologous BMCs to the graft material had no effect on implant fixation. The HA-grafted implants were poorly anchored compared with allografted implants, suggesting that coralline HA granules should be considered a bone graft extender rather than a bone graft substitute.

  2. Transmission of infection with human allografts: essential considerations in donor screening.

    Science.gov (United States)

    Fishman, Jay A; Greenwald, Melissa A; Grossi, Paolo A

    2012-09-01

    Transmission of infection via transplantation of allografts including solid organs, eyes, and tissues are uncommon but potentially life-threatening events. Donor-derived infections have been documented following organ, tissue, and ocular transplants. Each year, more than 70 000 organs, 100 000 corneas, and 2 million human tissue allografts are implanted worldwide. Single donors may provide allografts for >100 organ and tissue recipients; each allograft carries some, largely unquantifiable, risk of disease transmission. Protocols for screening of organ or tissue donors for infectious risk are nonuniform, varying with the type of allograft, national standards, and availability of screening assays. In the absence of routine, active surveillance, coupled with the common failure to recognize or report transmission events, few data are available on the incidence of allograft-associated disease transmission. Research is needed to define the optimal screening assays and the transmissibility of infection with allografts. Approaches are reviewed that may contribute to safety in allograft transplantation.

  3. Comparison of Clinical Outcome of Autograft and Allograft Reconstruction for Anterior Cruciate Ligament Tears

    Directory of Open Access Journals (Sweden)

    Yu-Hua Jia

    2015-01-01

    Conclusions: In the repair of ACL tears, allograft reconstruction is as effective as the autograft reconstruction, but the allograft can lead to more tunnel widening evidently in the tibial tunnel, particularly.

  4. Evaluation of Clinical Results and Complications of Structural Allograft Reconstruction after Bone Tumor Surgery

    Directory of Open Access Journals (Sweden)

    Mohammad Gharedaghi

    2016-07-01

    Full Text Available Background: Massive bone allograft is an option in cases of limb preservation and reconstruction after massive benign and malignant bone tumor resection. The purpose of this study was to analyze the outcome of these procedures at Imam Reza Hospital, Mashhad University of Medical Sciences. Methods: In this study, 113 cases have been presented. Eleven cases were excluded (patients has a traumatic defect or they passed away before the completion of the study’s two-year follow up period. Each patient completed a questionnaire, went through a physical examination and, if indicated, X-ray information was collected. The patients were divided into three groups: chemotherapy, chemotherapy plus radiation therapy, and no-adjuvant-therapy. Results: Fifty-four cases were male and the mean age was 24.5±5.39. The number of cases and indications for surgery were: 33 cases of aggressive benign tumors or low grade malignant bone tumors (large bone defects including 16 germ cell tumors, eight aneurysmal bone cysts, five low grade osteosarcomas, and four chondrosarcomas. Another 69 cases were high-grade malignant bone tumors including 42 osteosarcomas, 21 Ewing’s sarcoma, and six other high grade osteosarcomas. Patients were divided into three groups: the first group received no adjuvant therapy, the second group received chemotherapy, and the third group received chemotherapy plus radiotherapy. The location of tumors were as follows: eight cases in the pelvic bone, 12 in the proximal femur, 18 in the femoral shaft, 36 in the distal femur, 12 in the proximal tibia, and 16 in the humeral bone. The 12 cases of proximal femoral defects were reconstructed by allograft composite prosthesis, 18 diaphyseal defects with intercalary allograft, and 36 distal femoral defects were reconstructed using osteoarticular allograft. The rate of deep infection was 7:8% (eight patients and in this regard, we found a significant difference among the three groups, such that most

  5. Delayed minimally invasive injection of allogenic bone marrow stromal cell sheets regenerates large bone defects in an ovine preclinical animal model.

    Science.gov (United States)

    Berner, Arne; Henkel, Jan; Woodruff, Maria A; Steck, Roland; Nerlich, Michael; Schuetz, Michael A; Hutmacher, Dietmar W

    2015-05-01

    Cell-based tissue engineering approaches are promising strategies in the field of regenerative medicine. However, the mode of cell delivery is still a concern and needs to be significantly improved. Scaffolds and/or matrices loaded with cells are often transplanted into a bone defect immediately after the defect has been created. At this point, the nutrient and oxygen supply is low and the inflammatory cascade is incited, thus creating a highly unfavorable microenvironment for transplanted cells to survive and participate in the regeneration process. We therefore developed a unique treatment concept using the delayed injection of allogenic bone marrow stromal cell (BMSC) sheets to regenerate a critical-sized tibial defect in sheep to study the effect of the cells' regeneration potential when introduced at a postinflammatory stage. Minimally invasive percutaneous injection of allogenic BMSCs into biodegradable composite scaffolds 4 weeks after the defect surgery led to significantly improved bone regeneration compared with preseeded scaffold/cell constructs and scaffold-only groups. Biomechanical testing and microcomputed tomography showed comparable results to the clinical reference standard (i.e., an autologous bone graft). To our knowledge, we are the first to show in a validated preclinical large animal model that delayed allogenic cell transplantation can provide applicable clinical treatment alternatives for challenging bone defects in the future.

  6. Anterior cruciate ligament allograft transplantation for intraarticular ligamentous reconstruction.

    Science.gov (United States)

    Goertzen, M; Dellmann, A; Gruber, J; Clahsen, H; Bürrig, K F

    1992-01-01

    A multiplicity of surgical operations have been developed in an attempt to achieve satisfactory function after anterior cruciate ligament (ACL) repair. None of these procedures have been able to reproduce the fiber organization anatomy of attachment site, vascularity, or function of the ACL. Twenty-nine foxhounds received a deep-frozen bone-ACL-bone allograft and a ligament augmentation device (LAD). Biomechanical, microvascular, and histological changes were evaluated 3, 6, and 12 months following implantation. The maximum loads of the allograft/LADs were 34.3% (387.2 N) after 3 months, 49.3% (556.6 N) after 6 months, and 61.1% (698.8 N) after a year. The maximum load was 69.1% (780 N). In general, after 6 months the allografts showed normal collagen orientation. The allografts demonstrated no evidence of infection or immune reaction. No bone ingrowth into the LAD was observed. Polarized light microscopy and periodic acid-schiff staining showed that the new bone-ligament substance interface had intact fiber orientation at the area of the ligament insertion. Microvascular examination using the Spalteholtz technique revealed revascularization and the importance of an infrapatellar fat pad for the nourishment of ACL allografts.

  7. Differential gene expression pattern in biopsies with renal allograft pyelonephritis and allograft rejection

    Science.gov (United States)

    Oghumu, Steve; Nori, Uday; Bracewell, Anna; Zhang, Jianying; Bott, Cherri; Nadasdy, Gyongyi M.; Brodsky, Sergey V.; Pelletier, Ronald; Satoskar, Abhay R.; Nadasdy, Tibor; Satoskar, Anjali A.

    2016-01-01

    Differentiating acute pyelonephritis (APN) from acute rejection (AR) in renal allograft biopsies can sometimes be difficult because of overlapping clinical and histologic features, lack of positive urine cultures, and variable response to antibiotics. We wanted to study differential gene expression between AR and APN using biopsy tissue. Thirty-three biopsies were analyzed using NanoString multiplex platform and PCR (6 transplant baseline biopsies, 8 AR, 15 APN [8 culture positive, 7 culture negative], and 4 native pyelonephritis [NP]). Additional 22 biopsies were tested by PCR to validate the results. CXCL9, CXCL10, CXCL11, and IDO1 were the top differentially expressed genes, upregulated in AR. Lactoferrin (LTF) and CXCL1 were higher in APN and NP. No statistically significant difference in transcript levels was seen between culture-positive and culture-negative APN biopsies. Comparing the overall mRNA signature using Ingenuity pathway analysis, interferon-gamma emerged as the dominant upstream regulator in AR and allograft APN, but not in NP (which clustered separately). Our study suggests that chemokine pathways in graft APN may differ from NP and in fact resemble AR, due to a component of alloreactivity, resulting in variable response to antibiotic treatment. Therefore, cautious addition of steroids might help in resistant cases of graft APN. PMID:27352120

  8. Differential gene expression pattern in biopsies with renal allograft pyelonephritis and allograft rejection.

    Science.gov (United States)

    Oghumu, Steve; Nori, Uday; Bracewell, Anna; Zhang, Jianying; Bott, Cherri; Nadasdy, Gyongyi M; Brodsky, Sergey V; Pelletier, Ronald; Satoskar, Abhay R; Nadasdy, Tibor; Satoskar, Anjali A

    2016-09-01

    Differentiating acute pyelonephritis (APN) from acute rejection (AR) in renal allograft biopsies can sometimes be difficult because of overlapping clinical and histologic features, lack of positive urine cultures,and variable response to antibiotics. We wanted to study differential gene expression between AR and APN using biopsy tissue. Thirty-three biopsies were analyzed using NanoString multiplex platform and PCR (6 transplant baseline biopsies, 8 AR, 15 APN [8 culture positive, 7 culture negative], and 4 native pyelonephritis [NP]). Additional 22 biopsies were tested by PCR to validate the results. CXCL9, CXCL10, CXCL11, and IDO1 were the top differentially expressed genes, upregulated in AR. Lactoferrin (LTF) and CXCL1 were higher in APN and NP. No statistically significant difference in transcript levels was seen between culture-positive and culture-negative APN biopsies. Comparing the overall mRNA signature using Ingenuity pathway analysis, interferon-gamma emerged as the dominant upstream regulator in AR and allograft APN, but not in NP (which clustered separately). Our study suggests that chemokine pathways in graft APN may differ from NP and in fact resemble AR, due to a component of alloreactivity, resulting in variable response to antibiotic treatment. Therefore, cautious addition of steroids might help in resistant cases of graft APN.

  9. Innovative methods to use silicon sheets for high efficiency solar cells. Final report; Innovative Verfahren zum Einsatz von Siliciumfolien fuer hocheffiziente Solarzellen. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, W.

    2001-01-01

    This project was organised into three main activity units. The design and test of continuous process equipment and related handling and control systems for multicrystalline and EFG (edge-defined film-fed growth) silicon wafers lead to an important knowledge base for the design of a fully automated (pilot) production line for high efficiency solar cells, specially suited for the application of silicon sheets with their different surface morphology in comparison to conventional sliced silicon wafers. The development of new continuous processing equipment closed the gaps in the design concept of an automated production line to realise a simple process sequence and related innovative continuous processing schemes for the production of high efficiency solar cells from silicon sheets. Based on the results achieved so far, a fully automated pilot production line with continuous processing equipment for all process steps for the production of high efficiency solar cells was set up. The test results demonstrated the suitability of the selected concept for a future mass production in the 50 to 100 MW range: Mean cell efficiencies of 14% for EFG sheets and 14.5-15% for cast multicrystalline silicon wafers were achieved. A thorough cell production cost analysis based on all collected data revealed a 20% reduction in comparison to the former state-of-the-art. (orig.) [German] In diesem Vorhaben wurden drei Arbeitsschwerpunkte bearbeitet. Die Konzeption und Erprobung von Durchlaufanlagen und zugehoerigen Handhabungs- und Steuerungssystemen fuer mc(multikristalline)- und EFG(edge-defined film-fed growth)-Siliciumscheiben lieferte wesentliche Erkenntnisse fuer die Gestaltung einer vollautomatischen Pilotfertigung fuer hocheffiziente Solarzellen, speziell geeignet fuer den Einsatz von Siliciumfolien mit ihrer gegenueber konventionellen gesaegten Siliciumscheiben andersartigen Oberflaechenstruktur. Die Entwicklung neuartiger Durchlaufanlagen schloss die bestehenden Luecken im

  10. 分期实施异体角膜缘干细胞移植与穿透性角膜移植术治疗严重化学伤%A staged penetrating keratoplasty following limbal stem cells allograft in severe chemical injury leading to successful restoration of the ocular surface anatomy

    Institute of Scientific and Technical Information of China (English)

    Ali Hassan Alashwal; Raja Azmi Mohd Noor; Mohtar Ibrahim

    2008-01-01

    A 62-year-old man presented with severe bilateral ocular surface chemical injury and history of failed penetrating keratoplasty of right eye in 1996. Visual acuity was hand movement in right eye and light perception in left eye. Staged procedures of limbal stem cells allograft followed by penetrating keratoplasty have been done and resulted in good ocular surface restoration and rehabilitation of vision in right eye.%有1位于1996年实施右眼穿透性角膜移植术失败的双眼严重眼表化学伤的患者,62岁,右眼视力手动,左眼视力光感,于2006-09-16/2007-02-07分别对右眼实施了异体角膜缘干细胞移植术和穿透性角膜移植术,经过术后5mo的药物治疗观察,最终获得了右眼最佳矫正视力为6/30,角膜移植片透明,眼表得以重建,并未发现明显排斥迹象的良好效果.

  11. Lung transplantation: chronic allograft dysfunction and establishing immune tolerance.

    Science.gov (United States)

    Gracon, Adam S A; Wilkes, David S

    2014-08-01

    Despite significant medical advances since the advent of lung transplantation, improvements in long-term survival have been largely unrealized. Chronic lung allograft dysfunction, in particular obliterative bronchiolitis, is the primary limiting factor. The predominant etiology of obliterative bronchiolitis involves the recipient's innate and adaptive immune response to the transplanted allograft. Current therapeutic strategies have failed to provide a definitive treatment paradigm to improve long-term outcomes. Inducing immune tolerance is an emerging therapeutic strategy that abrogates allograft rejection, avoids immunosuppression, and improves long-term graft function. The aim of this review is to discuss the key immunologic components of obliterative bronchiolitis, describe the state of establishing immune tolerance in transplantation, and highlight those strategies being evaluated in lung transplantation.

  12. Cefuroxime, rifampicin and pulse lavage in decontamination of allograft bone.

    Science.gov (United States)

    Hirn, M; Laitinen, M; Pirkkalainen, S; Vuento, R

    2004-03-01

    The risk of bacterial infection through allogenic bone transplantation is one of the major problems facing tissue banks. Different screening methods and decontamination procedures are being used to achieve a safe surgical result. The purpose of this study was to investigate the contamination rate in fresh frozen bone allografts after treating them with different decontamination methods. The allografts were contaminated by rubbing on the operating theatre floor for 60 min, after which they were rinsed either with sterile physiological saline, cefuroxime or rifampicin solution or they were washed with low-pressure pulse lavage of sterile physiological saline. Our findings show that low-pressure pulse lavage with sterile saline solution is very effective in removing bacteria from bone allograft, when compared with the antibiotic solutions tested.

  13. Nebulized Pentamidine-Induced Acute Renal Allograft Dysfunction

    Directory of Open Access Journals (Sweden)

    Siddhesh Prabhavalkar

    2013-01-01

    Full Text Available Acute kidney injury (AKI is a recognised complication of intravenous pentamidine therapy. A direct nephrotoxic effect leading to acute tubular necrosis has been postulated. We report a case of severe renal allograft dysfunction due to nebulised pentamidine. The patient presented with repeated episodes of AKI without obvious cause and acute tubular necrosis only on renal histology. Nebulised pentamidine was used monthly as prophylaxis for Pneumocystis jirovecii pneumonia, and administration preceded the creatinine rise on each occasion. Graft function stabilised following discontinuation of the drug. This is the first report of nebulized pentamidine-induced reversible nephrotoxicity in a kidney allograft. This diagnosis should be considered in a case of unexplained acute renal allograft dysfunction.

  14. Intragraft Tubular Vimentin and CD44 Expression Correlate With Long-Term Renal Allograft Function and Interstitial Fibrosis and Tubular Atrophy

    NARCIS (Netherlands)

    J. Kers; Y.C. Xu-Dubois; E. Rondeau; N. Claessen; M.M. Idu; J.J.T.H. Roelofs; F.J. Bemelman; R.J.M. ten Berge; S. Florquin

    2010-01-01

    Background. Development of interstitial fibrosis and tubular atrophy (IF/TA) is the main histologic feature involved in renal allograft deterioration. The aim of this study was to validate whether de novo tubular expression of CD44 (transmembrane glycoprotein) and vimentin (mesenchymal cell marker),

  15. Blockade of T-lymphocyte KCa3.1 and Kv1.3 channels as novel immunosuppression strategy to prevent kidney allograft rejection

    DEFF Research Database (Denmark)

    Grgic, I; Wulff, H; Eichler, I;

    2009-01-01

    -lymphocyte activity. We investigated whether combined blockade of the T-cell K(+) channels K(Ca)3.1 and K(v)1.3, both of which regulate calcium signaling during lymphocyte activation, is effective in prevention of rejection of kidney allografts from Fisher rats to Lewis rats. All recipients were initially treated...

  16. Chronic cardiac allograft rejection: critical role of ED-A(+) fibronectin and implications for targeted therapy strategies.

    Science.gov (United States)

    Franz, Marcus; Neri, Dario; Berndt, Alexander

    2012-03-01

    Chronic cardiac allograft rejection is characterized by cardiac allograft vasculopathy (CAV) and cardiac interstitial fibrosis (CIF) causing severe long-term complications after heart transplantation and determining allograft function and patients' prognosis. Until now, there have been no sufficient preventive or therapeutic strategies. CAV and CIF are accompanied by changes in the extracellular matrix, including re-expression of the fetal fibronectin splice variant known as ED-A(+) fibronectin. This molecule has been shown to be crucial for the development of myofibroblasts (MyoFbs) as the main cell type in CIF and for the activation of vascular smooth muscle cells (VSMCs) as the main cell type in CAV. Relevant re-expression and protein deposition of ED-A(+) fibronectin has been demonstrated in animal models of chronic rejection, with spatial association to CAV and CIF, and a quantitative correlation to the rejection grade. The paper by Booth et al published in this issue of The Journal of Pathology could prove for the first time the functional importance of ED-A(+) fibronectin for the development of CIF as a main component of chronic cardiac rejection. Thus, promising conclusions for the development of new diagnostic, preventive, and therapeutic strategies for chronic cardiac rejection focusing on ED-A(+) fibronectin can be suggested.

  17. Premalignant and Malignant Skin Lesions in Two Recipients of Vascularized Composite Tissue Allografts (Face, Hands

    Directory of Open Access Journals (Sweden)

    Jean Kanitakis

    2015-01-01

    Full Text Available Recipients of solid organ transplants (RSOT have a highly increased risk for developing cutaneous premalignant and malignant lesions, favored by the lifelong immunosuppression. Vascularized composite tissue allografts (VCA have been introduced recently, and relevant data are sparse. Two patients with skin cancers (one with basal cell carcinoma and one with squamous cell carcinomas have been so far reported in this patient group. Since 2000 we have been following 9 recipients of VCA (3 face, 6 bilateral hands for the development of rejection and complications of the immunosuppressive treatment. Among the 9 patients, one face-grafted recipient was diagnosed with nodular-pigmented basal cell carcinoma of her own facial skin 6 years after graft, and one patient with double hand allografts developed disseminated superficial actinic porokeratosis, a potentially premalignant dermatosis, on her skin of the arm and legs. Similar to RSOT, recipients of VCA are prone to develop cutaneous premalignant and malignant lesions. Prevention should be applied through sun-protective measures, regular skin examination, and early treatment of premalignant lesions.

  18. The first experience of orthotropic implantation of decellularized mitral allograft

    Directory of Open Access Journals (Sweden)

    P. P. Yablonsky

    2015-01-01

    Full Text Available Traditional biological and mechanical valve substitutes have some well-known limitation, such as rapid deterioration of the tissue ones in young patient and the high risk of thrombosis and anticoagulation therapy complications for the mechanical ones. At the same time the aortic and pulmonary valves can already be replaced with decellularized allografts that showed promising results in terms of both hemodynamics and reliability while anticoagulation for them is not needed. This paper describes the first orthotropic implantation of the decellularized mitral valve allograft in sheep model. The original method without stabilizing ring is described, which have shown good echocardiographic results.

  19. A Case of Intraparenchymal Pseudoaneurysms in Kidney Allograft

    Science.gov (United States)

    Lorentz, Liam Antony; Hlabangana, Linda Tebogo; Davies, Malcolm

    2016-01-01

    Patient: Male, 31 Final Diagnosis: Intraparenchymal pseudo-aneurysms in kidney transplant Symptoms: Asymptomatic Medication: — Clinical Procedure: Percutaneous renal biopsy Specialty: Transplantology Objective: Diagnostic/therapeutic accidents Background: Percutaneous needle biopsy is routinely performed for renal allograft management. Vascular complications of the procedure include pseudoaneurysm and arterio-venous fistulae formation. Delayed diagnosis of these complications is due to their mostly asymptomatic and indolent nature. Case Report: We present a case of extensive intraparenchymal pseudoaneurysm formation within the inferior pole of the allograft, diagnosed two years following the most recent biopsy procedure. Conclusions: Renal pseudoaneurysms may only be diagnosed years after their formation as they are typically asymptomatic. PMID:27510594

  20. Rare presentations of cytomegalovirus infection in renal allograft recipients.

    Science.gov (United States)

    Ardalan, Mohammadreza

    2012-01-01

    Cytomegalovirus is the most common viral infection after kidney transplantation. Clinical presentations of cytomegalovirus infection range from asymptomatic infection to organ-specific involvement. Most symptomatic infections manifest as fever and cytopenia. The gastrointestinal tract is the most common site of tissue-invasive infection, often presenting as diarrhea or gastrointestinal bleeding. Gastrointestinal obstruction, perforation, thrombosis of large gastrointestinal veins, splenic artery thrombosis, and pancreatitis are rare gastrointestinal presentations of cytomegalovirus infection. Renal-allograft ureteral stricture and skin involvement are other rare presentations of cytomegalovirus infection. hemophagocytic syndrome, thrombotic microangiopathy, adrenal insufficiency, and renal allograft artery stenosis are other rare symptoms of cytomegalovirus infection.

  1. 两种细胞膜片对牙生物性种植体牙周再生影响的动物实验%Periodontal tissue in a bio-implant by periodontal ligament cells sheet and bone marrow stromal cells sheet

    Institute of Scientific and Technical Information of China (English)

    孙传明; 刘宏伟

    2014-01-01

    目的 应用牙周膜细胞(periodontal ligament cells,PDLC)膜片、骨髓基质细胞(bone marrow stromal cells,BMSC)膜片与自体牙根体外构建牙生物性种植体,研究构建具有新生牙周组织支持的生物性牙根的可行性.方法 拔除2只比格犬下颌两侧双尖牙制作缺牙区,将比格犬自体牙根预备成近似圆柱状.培养犬第3代PDLC和BMSC成细胞膜片,体外将PDLC和BMSC膜片单独或共同包裹于牙根表面构建自体牙根种植体,将种植体分为4组:①双膜片组(每只犬2颗),将PDLC、BMSC先后包裹于同一牙根表面;②PDLC膜片组(每只犬2颗),将PDLC单膜片包裹于牙根表面;③BMSC膜片组(每只犬2颗),将BMSC单膜片包裹于牙根表面;④无膜片组(空白对照组)(每只犬1颗),无膜片牙根.制作缺牙区手术8周后,将种植体植入自体缺牙区牙槽嵴,12周时取材制作石蜡切片行HE和Masson三色染色,观察各组切片的组织学结果.结果 PDLC膜片组种植体根面可见包括牙骨质、牙周膜及牙槽骨的牙周组织样结构,其中可见类似牙周穿通纤维样组织垂直插入根面及骨面;双膜片组种植体和BMSC膜片组种植体根面多为骨性结合;空白对照组亦未见牙周组织样结构形成.结论 PDLC膜片能促进牙生物性种植体的牙周再生,可部分再生出包括牙骨质、牙周膜和牙槽骨的复杂牙周组织.%Objective To fabricate the bio-implant supported by regenerated periodontal tissue utilizing periodontal ligament cells(PDLC)-bone marrow stromal cells(BMSC) sheet and natural root.Methods Premolars of 2 beagle dogs were extracted to prepare the implanted area.Autologous tooth roots were carved into cylinders.PDLC and BMSC separated from beagle dogs were cultured into cell sheets in medium.Tooth roots were wrapped by one type of cell sheets or both to fabricate bio-implant and divided into four groups,tooth roots were wrapped by PDLC sheets and BMSC sheets successively (2 samples

  2. Porous allograft bone scaffolds: doping with strontium.

    Directory of Open Access Journals (Sweden)

    Yantao Zhao

    Full Text Available Strontium (Sr can promote the process of bone formation. To improve bioactivity, porous allograft bone scaffolds (ABS were doped with Sr and the mechanical strength and bioactivity of the scaffolds were evaluated. Sr-doped ABS were prepared using the ion exchange method. The density and distribution of Sr in bone scaffolds were investigated by inductively coupled plasma optical emission spectrometry (ICP-OES, X-ray photoelectron spectroscopy (XPS, and energy-dispersive X-ray spectroscopy (EDS. Controlled release of strontium ions was measured and mechanical strength was evaluated by a compressive strength test. The bioactivity of Sr-doped ABS was investigated by a simulated body fluid (SBF assay, cytotoxicity testing, and an in vivo implantation experiment. The Sr molar concentration [Sr/(Sr+Ca] in ABS surpassed 5% and Sr was distributed nearly evenly. XPS analyses suggest that Sr combined with oxygen and carbonate radicals. Released Sr ions were detected in the immersion solution at higher concentration than calcium ions until day 30. The compressive strength of the Sr-doped ABS did not change significantly. The bioactivity of Sr-doped material, as measured by the in vitro SBF immersion method, was superior to that of the Sr-free freeze-dried bone and the Sr-doped material did not show cytotoxicity compared with Sr-free culture medium. The rate of bone mineral deposition for Sr-doped ABS was faster than that of the control at 4 weeks (3.28 ± 0.23 µm/day vs. 2.60 ± 0.20 µm/day; p<0.05. Sr can be evenly doped into porous ABS at relevant concentrations to create highly active bone substitutes.

  3. Diabetes Fact Sheet

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    ... diabetes by losing weight. Related information Fitness and nutrition Heart disease and stroke Obesity and weight loss fact sheet Physical activity fact sheet Pregnancy The javascript used in this widget is not ...

  4. Zika Virus Fact Sheet

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    ... sheets Fact files Questions & answers Features Multimedia Contacts Zika virus Fact sheet Updated 6 September 2016 Key ... and last for 2-7 days. Complications of Zika virus disease Based on a systematic review of ...

  5. Pharmacogenomics Fact Sheet

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    ... NIGMS NIGMS Home > Science Education > Pharmacogenomics Fact Sheet Pharmacogenomics Fact Sheet Tagline (Optional) Middle/Main Content Area What is pharmacogenomics? Pharmacogenomics (sometimes called pharmacogenetics) is a field of ...

  6. Structural Biology Fact Sheet

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    ... Home > Science Education > Structural Biology Fact Sheet Structural Biology Fact Sheet Tagline (Optional) Middle/Main Content Area What is structural biology? Structural biology is a field of science focused ...

  7. Immunosuppression of canine renal allograft recipients by CD4 and CD8 monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Watson, C.J.E.; Davies, H.S.; Rebello, P.R.U.B.; McNair, R.; Rasmussen, A.; Calne, R.Y.; Metcalfe, S.M. (Department of Surgery, University of Cambridge (United Kingdom)); Cobbold, S.P.; Thiru, S.; Waldmann, H. (Department of Pathology, University of Cambridge (United Kingdom))

    1994-01-01

    A state of tolerance to MHC mismatched allografts can be generated in rodents by treatment with CD4 and CD8 monoclonal antibodies (mAb). In order to transpose this type of therapy to large animals and ultimately to the clinic, a suitable model is required. To this end we have generated a series of mAb to the canine CD4, CD8, and Thy-l antigens and have tested their ability to prevent rejection of renal allografts. Donor-recipient pairs were selected from a colony of mongrel dogs in which untreated rejection of two haplotype-mismatched kidneys occurred by day 7 (defined as a serum creatinine > 300 [mu]mol/l). Therapy with either the CD4 or the CD8 mAb, using no other immunosuppression, did not prolong graft survival. Depletion of T cells by a Thy-l mAb prior to surgery only extended graft survival to day 9. However, treating with combinations of mAb up to day 10 (CD4 plus Thy-l; CD4 plus CD8; or CD4 plus CD8 plus Thy-l) prolonged renal allograft function up to 25 days. Combination of the triple mAb therapy with a sub-therapeutic immunosuppressive drug regimen (cyclosporin A plus azathioprine that alone gave a median survival of 15 days) favored survival to a median of 38 days. This protocol also inhibited the antiglobulin response that had curtailed the effects of mAb treatment, opening the way to more extended, and potentially tolerizing, mAb plus drug regimens. (au) (23 refs.).

  8. No effect of platelet-rich plasma with frozen or processed bone allograft around noncemented implants

    DEFF Research Database (Denmark)

    Jensen, T B; Rahbek, O; Overgaard, S

    2005-01-01

    We compared processed morselized bone allograft with fresh-frozen bone graft around noncemented titanium implants. Also, the influence of platelet-rich plasma (PRP) in combination with bone allograft was evaluated. Analysis was based on implant fixation and histomorphometry. PRP was prepared...... by isolating the buffy coat from autologous blood samples. Bone allograft was used fresh-frozen or processed by defatting, freeze drying, and irradiation. Cylindrical hydroxyapatite-coated titanium implants were inserted bilaterally in the femoral condyles of eight dogs. Each implant was surrounded by a 2.5-mm...... concentric gap, which was filled randomly according to the four treatment groups--group 1: fresh-frozen bone allograft; group 2: processed bone allograft; group 3: fresh-frozen bone allograft + PRP; group 4: processed bone allograft + PRP. Histological and mechanical evaluation demonstrated no influence...

  9. The investigation of human periodontal ligament cell-sheet in vitro%人牙周韧带细胞膜片的体外实验研究

    Institute of Scientific and Technical Information of China (English)

    张剑英; 付云; 俞少杰

    2013-01-01

    Objective To investigate human periodontal ligament cells' capacities of osteogenesis and adipogenesis,and to identify the expression of type-Ⅰ collagen,laminin and fibronectin which are the main components of extracellular matrix in human periodontal ligament cell sheet through establish cell sheet model in vitro experiment.Methods Human periondontal ligament cells were purified and cultured by using enzymes digesting/tissue culture method.Immunocytochemistry was applied to identify the source and putative stem-cell marker STRO-1 of hPDLCs.The second to fourth passages of hPDLCs were cultured in the osteogenic medium and adipogenic medium for indicated days.Alizarin red and Oil red O staining method were applied to identify capabilities of osteogenesis and adipogenesis of hPDLCs.Haematoxylin-eosin staining and immunohistochemistry were applied to identify expression of type-Ⅰ collagen,laminin and fibronectin in hPDLCs cell sheet.Results The cultured hPDLCs demonstrated extensive proliferation and could be expanded in vitro.Immunostaining demonstrated that the cells expressed intermediate filament protein vimentin and the mesenchymal stem-cell marker STRO-1.hPDLCs in the osteogenic medium formed alizarin red-positive nodules.When hPDLCs were incubated in adipogenic medium,the cells developed into oil red O-positive lipid clusters and a significant high expression of type-Ⅰ collagen,laminin and fibronectin in human periodontalligament cell sheet.Conclusions Our findings confirm that hPDLCs contained stem cells population from culture,source identification,expression of the mesenchymai stem cell marker STRO-1,multilineage differentiation potent under defined culture conditions.Our study indicates that the hPDLCs turn out to be an efficient source and cell sheet to be an excellent bio-material that can be used for periodontal tissue regeneration.%目的 观察体外培养人牙周韧带细胞(hPDLCs)的成骨、成脂能力;构建hPDLCs膜片并鉴定膜片

  10. Roles of B lymphocyte and plasma cell in liver allograft of acute and chronic rejection%肝脏移植急、慢性排斥反应时移植肝内B淋巴细胞和浆细胞的变化和意义

    Institute of Scientific and Technical Information of China (English)

    宋继勇; 石炳毅; 杜国盛; 朱志东; 邹一平; 金海龙

    2010-01-01

    Objective To explore the roles of B lymphocyte and plasma cell in liver allograft re-jection to find the evidences of humoral factor participating in the rejection. Methods Immunohisto-chemical inspection of C4d, CD20+ B lymphocytes and CD138+ plasma cells were performed in 34 liver biopsy specimens from 25 patients with hepatic injury and their preoperative specimens. Then we ob-served the variances of the above parameters in the liver biopsy specimens and the differences of them with different hepatic injuries. We further observed the relation of the presence of CD20+ B lympho-cytes and CD138+ plasma cells to C4d positivity. Meanwhile, we compared the difficulties of clinical therapy with different presences of CD20+ B lymphocytes and CD138+ plasma cells in the liver biopsy specimens. Results The positive ratios of CD20+B lymphocytes and CD138+ plasma cells were signif-icantly higher in the acute rejection group than in the non-rejection group(P<0. 05 and P<0. 01).The positive ratios of CD20+ B lymphocytes were markedly higher in the chronic rejection group than in the non-rejection group(P<0. 05). There was no difference in CD138+ plasma cells between the 2 groups. The degrees of hepatic injury could not influence the positive ratioes of CD138+ plasma, but the positive ratioes of CD20+ B lymphocytes in the heavy hepatic injury groups was higher than in the slight hepatic injury groups(P<0. 05). CD20+ B lymphocytes and CD138+ plasma cells presented fol-lowing C4d(P<0. 01 and P<0. 05). The effective power of steroid in the all-positive group was obvi-ously lower than in the all-negative group(P<0. 05). Conclusion Humoral immune may participate in some liver allograft rejection. It would be more favorable for observing and prewarning the humoral re-jection by finding CD20, CD138 and C4d by immunohistochemical staining in liver biopsy specimens with hepatic injury after liver transplantation. It would be helpful for choosing the therapeutic regi-mens of liver

  11. Left versus right deceased donor renal allograft outcome.

    LENUS (Irish Health Repository)

    Phelan, Paul J

    2009-12-01

    It has been suggested that the left kidney is easier to transplant than the right kidney because of the longer length of the left renal vein, facilitating the formation of the venous anastomosis. There are conflicting reports of differing renal allograft outcomes based on the side of donor kidney transplanted (left or right).We sought to determine the effect of side of donor kidney on early and late allograft outcome in our renal transplant population. We performed a retrospective analysis of transplanted left-right deceased donor kidney pairs in Ireland between January 1, 1998 and December 31, 2008. We used a time to death-censored graft failure approach for long-term allograft survival and also examined serum creatinine at different time points post-transplantation. All outcomes were included from day of transplant onwards. A total of 646 transplants were performed from 323 donors. The incidence of delayed graft function was 16.1% in both groups and there was no significant difference in acute rejection episodes or serum creatinine from 1 month to 8 years post-transplantation.There were 47 death-censored allograft failures in the left-sided group compared to 57 in the right-sided group (P = 0.24). These observations show no difference in renal transplant outcome between the recipients of left- and right-sided deceased donor kidneys.

  12. Pulse lavage washing in decontamination of allografts improves safety.

    Science.gov (United States)

    Hirn, M; Laitinen, M; Vuento, R

    2003-01-01

    We analyzed the bacterial contamination rate of 140 femoral head allografts after rinsing the allografts in different decontamination solutions. Bacterial screening methods and cleansing effect of antibiotics (cefuroxime and rifampicin) and pulse lavage were compared. Swabbing and taking small pieces of bone for culture were the screening methods used. Both methods proved to be quite unreliable. Approximately one-fourth of the results were false negative. Culturing small pieces of bone gave the most accurate and reliable results and, therefore, can be recommended as a bacterial screening method. The use of antibiotics in allograft decontamination is controversial. In prophylactic use antibiotics include risks of allergic reactions and resistant development and our results in the present study show that antibiotics do not improve the decontamination any better than low-pressure pulse lavage with sterile saline solution. Therefore, pulse lavage with sterile saline solution can be recommended for allograft decontamination. Our results demonstrate that it decreases bacterial bioburden as effectively as the antibiotics without persisting the disadvantages.

  13. Effects of Acute Cytomegalovirus Infection on Rat Islet Allograft Survival

    NARCIS (Netherlands)

    Smelt, M. J.; Faas, M. M.; Melgert, B. N.; de Vos, P.; de Haan, Bart; de Haan, Aalzen

    2011-01-01

    Transplantation of pancreatic islets is a promising therapy for the treatment of type 1 diabetes mellitus. However, long-term islet graft survival rates are still unsatisfactory low. In this study we investigated the role of cytomegalovirus (CMV) in islet allograft failure. STZ-diabetic rats receive

  14. Efficacy of isoniazid prophylaxis in renal allograft recipients.

    Science.gov (United States)

    Naqvi, R; Akhtar, S; Noor, H; Saeed, T; Bhatti, S; Sheikh, R; Ahmed, E; Akhtar, F; Naqvi, A; Rizvi, A

    2006-09-01

    The efficacy of isoniazid (INH) prophylaxis in renal allograft recipients who are on long-term immunosuppression in a region highly prevalent for tuberculosis (TB) was studied. INH (300 mg/d in patients weighing more than 35 kg and 5 mg/kg/d in patients with Pyridoxine 50 mg/d for 1 year was started in randomly assigned renal allograft recipients. Occurrence of clinical tuberculosis during the initial 2 years posttransplantation was observed in the risk group and patients at no risk. Risks were defined as acute rejection episodes and exposure to antirejection therapy, past history of TB completely or incompletely treated, radiological evidence of past tuberculosis, history of tuberculosis in close contacts. Among 480 patients registered in the study, INH prophylaxis was given to 219 randomly assigned renal allograft recipients. Results were compared among patients developing TB during the initial 2 years posttransplantation in both the groups. Risk factors were analyzed for comparison in both groups. No significant difference was observed in terms of past history of TB, TB in close contacts, episodes of acute rejection during the initial 3 months, and comorbidities such as cytomegalovirus infection, hepatitis C virus infection, and posttransplant diabetes. One patient from the INH group and 10 patients from the non-INH group developed TB during the initial 2 years posttransplantation (P < .0001). None of patients required discontinuation of INH. INH was observed to be safe and effective as a chemoprophylactic agent in renal allograft recipients.

  15. Recurrence of Acute Page Kidney in a Renal Transplant Allograft

    Science.gov (United States)

    Zayas, Carlos; Mulloy, Laura; Jagadeesan, Muralidharan

    2016-01-01

    Acute Page Kidney (APK) phenomenon is a rare cause of secondary hypertension, mediated by activation of renin-angiotensin-aldosterone system (RAAS). Timely intervention is of great importance to prevent any end organ damage from hypertension. We present a unique case of three episodes of APK in the same renal transplant allograft. PMID:27725836

  16. Recurrence of Acute Page Kidney in a Renal Transplant Allograft

    Directory of Open Access Journals (Sweden)

    Rajan Kapoor

    2016-01-01

    Full Text Available Acute Page Kidney (APK phenomenon is a rare cause of secondary hypertension, mediated by activation of renin-angiotensin-aldosterone system (RAAS. Timely intervention is of great importance to prevent any end organ damage from hypertension. We present a unique case of three episodes of APK in the same renal transplant allograft.

  17. Recurrence of Acute Page Kidney in a Renal Transplant Allograft.

    Science.gov (United States)

    Kapoor, Rajan; Zayas, Carlos; Mulloy, Laura; Jagadeesan, Muralidharan

    2016-01-01

    Acute Page Kidney (APK) phenomenon is a rare cause of secondary hypertension, mediated by activation of renin-angiotensin-aldosterone system (RAAS). Timely intervention is of great importance to prevent any end organ damage from hypertension. We present a unique case of three episodes of APK in the same renal transplant allograft.

  18. Tuberculosis in a renal allograft recipient presenting with intussusception.

    Science.gov (United States)

    Mohapatra, A; Basu, G; Sen, I; Asirvatham, R; Michael, J S; Pulimood, A B; John, G T

    2012-01-01

    Extra-pulmonary tuberculosis (TB) is more common in renal allograft recipients and may present with dissemination or an atypical features. We report a renal allograft recipient with intestinal TB presenting 3 years after transplantation with persistent fever, weight loss, diarrhea, abdominal pain and mass in the abdomen with intestinal obstruction. He was diagnosed to be having an ileocolic intussusception which on resection showed a granulomatous inflammation with presence of acid-fast bacilli (AFB) typical of Mycobacterium tuberculosis. In addition, AFB was detected in the tracheal aspirate, indicating dissemination. He received anti-TB therapy (ATT) from the fourth postoperative day. However, he developed a probable immune reconstitution inflammatory syndrome (IRIS) with multiorgan failure and died on 11(th) postoperative day. This is the first report of intestinal TB presenting as intussusception in a renal allograft recipient. The development of IRIS after starting ATT is rare in renal allograft recipients. This report highlights the need for a high index of suspicion for diagnosing TB early among renal transplant recipients and the therapeutic dilemma with overwhelming infection and development of IRIS upon reduction of immunosuppression and starting ATT.

  19. Identification and treatment of cyclosporine-associated allograft thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Schlanger, R.E.; Henry, M.L.; Sommer, B.G.; Ferguson, R.M.

    1986-08-01

    Endothelial injury associated with cyclosporine (CSA) therapy in the absence of rejection has resulted in irreversible intrarenal allograft thrombosis and transplant loss. Indium 111 (/sup 111/In)-labeled platelet scanning is an effective way to identify those transplants that are at risk for acute loss. Two hundred prospective /sup 111/In scans were obtained (100 on allografts with normal function and 100 with transplant dysfunction of all causes). /sup 111/In scans in patients with dose-dependent CSA nephrotoxicity (N = 58) and biopsy proved acute rejection (N = 22) were negative. Grossly abnormal scans (three to eight times greater than hepatic uptake) were noted in nine recipients identified as having a hemolytic uremic-like syndrome associated with CSA use. Accelerated allograft functional loss was irreversible in six patients despite stopping CSA, systemic anticoagulation, increased steroids and antilymphocyte globulin, and infusion of fresh-frozen plasma. Three patients with grossly positive /sup 111/In scans and clinical and laboratory parameters consistent with this syndrome were treated with cessation of CSA and intra-arterial infusion of streptokinase into the renal allograft followed by systemic heparinization. Normal transplant function was regained and continues at 1, 7, and 8 months after transplant. /sup 111/In-labeled platelet scanning can noninvasively identify this syndrome of CSA-associated arteriopathy and allow for early therapy to reverse it. Intrarenal arterial streptokinase therapy is a successful way to treat acute CSA-associated arteriopathy.

  20. Clean, Efficient, and Reliable Heat and Power for the 21st Century, Fuel Cell Technologies Program (FCTP) (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2010-05-01

    This overview of the U.S. Department of Energy's Fuel Cell Technologies Program describes the program's focus and goals, along with current fuel cell applications and future potential. The program focuses on research and development of fuel cell systems for diverse applications in the stationary power, portable power, and transportation sectors. It works to reduce costs and improve technologies to advance fuel cell uses in areas such as combined heat and power, auxiliary power units, portable power systems, and stationary and backup power. To help ensure that fuel cell advances are realized, the program rigorously analyzes energy efficiency, economic, and environmental benefits of fuel cells and seeks to optimize synergies among fuel cell applications and other renewable technologies.

  1. 组织工程牙周膜细胞片的体内实验研究%An in vivo study of cell sheet technique for periodontal tissue engineering

    Institute of Scientific and Technical Information of China (English)

    王方; 谢诚; 吴国锋; 赵铱民

    2011-01-01

    目的:探索一种形成组织工程牙周膜的新方法并建立动物模型,为牙周组织工程奠定基础.方法:原代分离培养人牙周膜细胞,部分细胞复合明胶海绵设为对照组;另一部分细胞经特殊条件连续培养成细胞膜片设为实验组.2 组实验结果择优复合支架材料后植入裸鼠皮下,4 周后取材行组织病理检测.结果:经特殊条件连续培养的牙周膜细胞层叠交错相连形成具有良好的机械加工性能的生物膜片,该膜片经裸鼠体内培养形成牙周膜样组织,并在近羟基磷灰石支架侧有矿化的牙骨质样结构生成.结论:该方法制备的牙周膜细胞片在牙周组织工程具有良好的应用前景.%Objective: To develop a new way of preparation of periodontal ligament cell(PDLC) sheet and establish an animal test model. Methods: Primarily cultured human PDL cells were seeded on the surface of geffoam as the control group,and those continuously cultured in perti dishes as the experimental group. In control group no cell sheet was formed,but in experimental group cell sheets were developed. Then, the cell sheets were used to cover hydroxyapatite(HA) scafford and transplanted under the skin of immunocompromised mice. 4 weeks after implantation, the transplants were examined by histological methods ( HE staining and Masson's trichrome staining). Results: 4 weeks after implantation, PDLCs and matrix secreted by the cells formed a periodontal ligament like multilayer cell sheet on HA. Each layer of the whole sheet was connected tightly and could be shaped easily. Also, the periodontal ligament like tissue mineralized a layer of cementum like structure on HA scaffold. Conclusion: The multilayered cell sheet technique may be a novel strategy for periodontal regeneration.

  2. Metabolomic Profiling in Individuals with a Failing Kidney Allograft

    Science.gov (United States)

    Biancone, Luigi; Bussolino, Stefania; Merugumala, Sai; Tezza, Sara; D’Addio, Francesca; Ben Nasr, Moufida; Valderrama-Vasquez, Alessandro; Usuelli, Vera; De Zan, Valentina; El Essawy, Basset; Venturini, Massimo; Secchi, Antonio; De Cobelli, Francesco; Lin, Alexander; Chandraker, Anil; Fiorina, Paolo

    2017-01-01

    Background Alteration of certain metabolites may play a role in the pathophysiology of renal allograft disease. Methods To explore metabolomic abnormalities in individuals with a failing kidney allograft, we analyzed by liquid chromatography-mass spectrometry (LC-MS/MS; for ex vivo profiling of serum and urine) and two dimensional correlated spectroscopy (2D COSY; for in vivo study of the kidney graft) 40 subjects with varying degrees of chronic allograft dysfunction stratified by tertiles of glomerular filtration rate (GFR; T1, T2, T3). Ten healthy non-allograft individuals were chosen as controls. Results LC-MS/MS analysis revealed a dose-response association between GFR and serum concentration of tryptophan, glutamine, dimethylarginine isomers (asymmetric [A]DMA and symmetric [S]DMA) and short-chain acylcarnitines (C4 and C12), (test for trend: T1-T3 = p<0.05; p = 0.01; p<0.001; p = 0.01; p = 0.01; p<0.05, respectively). The same association was found between GFR and urinary levels of histidine, DOPA, dopamine, carnosine, SDMA and ADMA (test for trend: T1-T3 = p<0.05; p<0.01; p = 0.001; p<0.05; p = 0.001; p<0.001; p<0.01, respectively). In vivo 2D COSY of the kidney allograft revealed significant reduction in the parenchymal content of choline, creatine, taurine and threonine (all: p<0.05) in individuals with lower GFR levels. Conclusions We report an association between renal function and altered metabolomic profile in renal transplant individuals with different degrees of kidney graft function. PMID:28052095

  3. ACL graft failure location differs between allografts and autografts

    Directory of Open Access Journals (Sweden)

    Magnussen Robert A

    2012-06-01

    Full Text Available Abstract Background Between 5 and 20% of patients undergoing ACL reconstruction fail and require revision. Animal studies have demonstrated slower incorporation of allograft tissue, which may affect the mechanism of graft failure. The purpose of this study is to determine the location of traumatic graft failure following ACL reconstruction and investigate differences in failure patterns between autografts and allografts. Methods The medical records of 34 consecutive patients at our center undergoing revision ACL reconstruction following a documented traumatic re-injury were reviewed. Graft utilized in the primary reconstruction, time from initial reconstruction to re-injury, activity at re-injury, time to revision reconstruction, and location of ACL graft tear were recorded. Results Median patient age at primary ACL reconstruction was 18.5 years (range, 13–39 years. The primary reconstructions included 20 autografts (13 hamstrings, 6 patellar tendons, 1 iliotibial band, 12 allografts (5 patellar tendon, 5 tibialis anterior tendons, 2 achilles tendons, and 2 unknown. The median time from primary reconstruction to re-injury was 1.2 years (range, 0.4 – 17.6 years. The median time from re-injury to revision reconstruction was 10.4 weeks (range, 1 to 241 weeks. Failure location could be determined in 30 patients. In the autograft group 14 of 19 grafts failed near their femoral attachment, while in the allograft group 2 of 11 grafts failed near their femoral attachment (p  Conclusions When ACL autografts fail traumatically, they frequently fail near their femoral origin, while allograft reconstructions that fail are more likely to fail in other locations or stretch. Level of evidence Level III - Retrospective cohort study

  4. Photovoltaics Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-02-01

    This fact sheet is an overview of the Photovoltaics (PV) subprogram at the U.S. Department of Energy SunShot Initiative. The U.S. Department of Energy (DOE)’s Solar Energy Technologies Office works with industry, academia, national laboratories, and other government agencies to advance solar PV, which is the direct conversion of sunlight into electricity by a semiconductor, in support of the goals of the SunShot Initiative. SunShot supports research and development to aggressively advance PV technology by improving efficiency and reliability and lowering manufacturing costs. SunShot’s PV portfolio spans work from early-stage solar cell research through technology commercialization, including work on materials, processes, and device structure and characterization techniques.

  5. 术前输注供者CD80low/CD86low树突状细胞延长小鼠同种异体移植心脏存活%Donor dendritic cells treated with B7- 1, B7- 2 antisense oligonucleotide prolonged mouse cardiac allograft survival

    Institute of Scientific and Technical Information of China (English)

    梁晓燕; 陈宗佑; 钱诗光; 李树浓

    2000-01-01

    AIM:To investigate the effect of donor bone marrow derived dentritic cell (DC) treated with B7 - 1, B7 - 2 antisense oligonucleotide on mouse heart allografe survival time and its mechanism. METHODS: There were 7 groups of C57BL/10J (B10) mouse bone marrow DCs which were treated by 400 nM antisense oligonucleotide target to B7 -1, B7 -2 mRNA (AS B7- 1/2), B7- 1 mismatch oligo control ,B7- 2 mismatch control(mASB7- 1/2), lipofeetamine only and non-treatment, respectively. Each group of DC were named as ASB7- 1 DC, ASB7- 2 DC, mASB7 - 1 DC, mAS B7 - 2DC, and Lipo DC, respectively. RESULTS: Flow cytometer results shown that AS B7- 1/2 can inhibit B7- 1 (CD80)and B7- 2 (CD86) molecule express on DC surface, while control groups have no effects. To observe their tolerogenicity in mouse cardiac allograft model, B10→C3H heterotopic heart transplantation were performed. Recepients were received 2 x 106 of DC injection 7 days before transplantation. Results showed that both AS B7 - 1 DC and AS B7 - 2 DC can prolong mouse cardiac allograft survival time to (18.6 + 0.89) days and (23.67 + 10.73) days, respectively, compared with IL - 4 DC [ (6.22 + 0.97) days ( P < 0.01 ) ]. Two mismatch control groups can slightly prolong while oligo DC has no effect. For understanding its mechanism, each group of DC was used as stimulator to stimulated C3H spleen T cell. Results suggested that AS B7 - 1DC and AS B7 - 2 DC had less allo - stimulate function, including MLR and generation CTL and IL - 2 production than IL - 4 DC but control groups have no effect. CONCLUSION: Donor bone marrow derived DC treated with AS B7 - 1 oligo and AS B7 - 2 oligo expressed lower level of CD80 and CD86, respectively. These cells can induce allogeneic T cells anergy in vitro and markedly prolong mouse heart allograft survival time in vivo.%目的:应用B7-1和B7-2反义寡核苷酸(AS B7-1/AS B7-2 oligo)抑制CD80(B7-1)、CD86(B7-2)在供体小鼠骨髓树突状细胞(DC)上的表达,观察这类DC

  6. 异体脂肪源干细胞移植对糖皮质激素性骨质疏松大鼠的影响%Effects of systemic transplantation of allograft adipose-derived stem cells in glucocorticoid-induced osteoporosis rats

    Institute of Scientific and Technical Information of China (English)

    陶晖; 杨会营; 余美春; 杨春; 曾文钦; 段富华; 戴景兴; 原林

    2011-01-01

    目的 基于"筋膜学假说",探索未分化非特异性结缔组织(筋膜)支架构成的支持与储备系统中的主要细胞储备成分--脂肪源干细胞(ADSCs)移植对糖皮质激素性骨质疏松大鼠骨密度及骨生物力学的影响.方法 40只Wistar雌性大鼠随机分为空白对照组、模型组、治疗组和治疗对照组.利用糖皮质激素建立骨质疏松模型后,经尾静脉移植ADSCs 3×106个/只进行治疗.测定血清Ca、P、碱性磷酸酶(ALP)的含量,L3~L5椎体和右侧股骨骨密度以及左侧股骨最大载荷和刚度.结果糖皮质激素注射12周后,模型组血清Ca和ALP、骨密度、最大载荷和刚度均明显低于空白对照组,而血清P明显升高 (P<0.01).ADSCs治疗4周后,治疗组血清Ca和ALP、骨密度、最大载荷和刚度均明显升高,而血清P水平下降.结论移植异体ADSCs可以有效改善糖皮质激素性骨质疏松大鼠的骨密度和骨生物力学性能,为糖皮质激素性骨质疏松的治疗提供了新的治疗方法,并为"筋膜学假说"提供了部分实验依据.%Objective To investigate the effects of systemic transplantation of allograft adipose-derived stem cells (ADSCs), which are mainly undifferentiated stem cells in the supporting and storing system consisting of the non-specific connective tissue (fascia) stent, on the bone mineral density (BMD) and bone biomechanics in glucocorticoid-indueed osteoporosis (GIOP) rats based on fasciaology hypothesis, and to explore a new therapeutics for osteoporosis. Methods Totally 40 female adult Wistar rats were randomly divided into four groups: blank control group ( A ), model group ( B ) ,treatment group(C) and treatment control group(D) (n = 10). Rats were induced osteoporosis by injected prednisolone.Then each rat was treated with ADSCs 3 × 106 via tail vein injection. BMD of L3-L5 and right femurs, strength and stiffness of left femurs, the levels of serum Ca、P and glkaline phosphatase(ALP) were

  7. One-step fabrication of copper sulfide nanoparticles decorated on graphene sheets as highly stable and efficient counter electrode for CdS-sensitized solar cells

    Science.gov (United States)

    Hessein, Amr; Wang, Feiju; Masai, Hirokazu; Matsuda, Kazunari; Abd El-Moneim, Ahmed

    2016-11-01

    Quantum-dot-sensitized solar cells (QDSSCs) are thin-film photovoltaics and highly promising as next-generation solar cells owing to their high theoretical efficiency, easy fabrication process, and low production cost. However, the practical photoconversion efficiencies (PCEs) of QDSSCs are still far below the theoretically estimated value owing to the lack of an applicable design of the materials and electrodes. In this work, we developed a highly stable and efficient counter electrode (CE) from copper sulfide nanocrystals and reduced graphene oxide (Cu x S@RGO) for QDSSC applications. The Cu x S@RGO electrocatalyst was successfully prepared by a facile one-pot hydrothermal method, then directly applied to a fluorine-doped tin oxide (FTO)-coated glass substrate by the simple drop-casting technique. Owing to the synergistic effect between Cu x S nanocrystals and conductive RGO sheets, the Cu x S@RGO CE showed high electrocatalytic activity for polysulfide electrolyte reduction. A CdS QDSSC based on the Cu x S@RGO CE yielded a high and reproducible PCE of 2.36%, exceeding those of 1.57 and 1.33% obtained with the commonly used Cu2S/brass and Pt CEs, respectively. Moreover, the QDSSC with the Cu x S@RGO CE showed excellent photostability in a light-soaking test without any obvious decay in the photocurrent, whereas the cell based on the Cu2S/brass CE was severely degraded.

  8. The Impact of Ischemia/Reperfusion Injury on Liver Allografts from Deceased after Cardiac Death versus Deceased after Brain Death Donors.

    Directory of Open Access Journals (Sweden)

    Jin Xu

    Full Text Available The shortage of organs for transplantation has led to increased use of organs procured from donors after cardiac death (DCD. The effects of cardiac death on the liver remain poorly understood, however. Using livers obtained from DCD versus donors after brain death (DBD, we aimed to understand how ischemia/reperfusion (I/R injury alters expression of pro-inflammatory markers ceramides and influences graft leukocyte infiltration.Hepatocyte inflammation, as assessed by ceramide expression, was evaluated in DCD (n = 13 and DBD (n = 10 livers. Allograft expression of inflammatory and cell death markers, and allograft leukocyte infiltration were evaluated from a contemporaneous independent cohort of DCD (n = 22 and DBD (n = 13 livers.When examining the differences between transplant stages in each group, C18, C20, C24 ceramides showed significant difference in DBD (p<0.05 and C22 ceramide (p<0.05 were more pronounced for DCD. C18 ceramide is correlated to bilirubin, INR, and creatinine after transplant in DCD. Prior to transplantation, DCD livers have reduced leukocyte infiltration compared to DBD allografts. Following reperfusion, the neutrophil infiltration and platelet deposition was less prevalent in DCD grafts while cell death and recipients levels of serum aspartate aminotransferase (AST of DCD allografts had significantly increased.These data suggest that I/R injury generate necrosis in the absence of a strong inflammatory response in DCD livers with an appreciable effect on early graft function. The long-term consequences of increased inflammation in DBD and increased cell death in DCD allografts are unknown and warrant further investigation.

  9. Novel Therapeutics Identification for Fibrosis in Renal Allograft Using Integrative Informatics Approach

    Science.gov (United States)

    Li, Li; Greene, Ilana; Readhead, Benjamin; Menon, Madhav C.; Kidd, Brian A.; Uzilov, Andrew V.; Wei, Chengguo; Philippe, Nimrod; Schroppel, Bernd; He, John Cijiang; Chen, Rong; Dudley, Joel T.; Murphy, Barbara

    2017-01-01

    Chronic allograft damage, defined by interstitial fibrosis and tubular atrophy (IF/TA), is a leading cause of allograft failure. Few effective therapeutic options are available to prevent the progression of IF/TA. We applied a meta-analysis approach on IF/TA molecular datasets in Gene Expression Omnibus to identify a robust 85-gene signature, which was used for computational drug repurposing analysis. Among the top ranked compounds predicted to be therapeutic for IF/TA were azathioprine, a drug to prevent acute rejection in renal transplantation, and kaempferol and esculetin, two drugs not previously described to have efficacy for IF/TA. We experimentally validated the anti-fibrosis effects of kaempferol and esculetin using renal tubular cells in vitro and in vivo in a mouse Unilateral Ureteric Obstruction (UUO) model. Kaempferol significantly attenuated TGF-β1-mediated profibrotic pathways in vitro and in vivo, while esculetin significantly inhibited Wnt/β-catenin pathway in vitro and in vivo. Histology confirmed significantly abrogated fibrosis by kaempferol and esculetin in vivo. We developed an integrative computational framework to identify kaempferol and esculetin as putatively novel therapies for IF/TA and provided experimental evidence for their therapeutic activities in vitro and in vivo using preclinical models. The findings suggest that both drugs might serve as therapeutic options for IF/TA. PMID:28051114

  10. Re-epithelializaiton by epithelial inoculation with recipient phenotype in heterotopically transplanted rat allografts

    Institute of Scientific and Technical Information of China (English)

    Zheng Hui; Hu Xuefei; Li Chao; Xie Huikang; Gao Wen; Chen Chang

    2014-01-01

    Background Re-epithelialization has remained a major obstacle in both tracheal and lung transplantations.This study examines the realization of re-epithelialization by epithelial inoculation in a rat heterotopic tracheal transplantation model.Methods The original epithelia of tracheas from donor Wistar rats were removed and the tracheas were then inoculated with 106/ml in vitro cultured epithelial cells of the Spraque-Dawley (SD) rat phenotype.These allo-tracheas were then heterotopically transplanted into SD rats.After 28 days,the allo-trachea tissues were recovered and assessed for epithelial morphology and cellular differentiation using immunohistochemical analysis.An additional experimental group was used to compare the outcomes of re-epithelialization in immunosuppressed animals.Results Histological examination showed that allografts with epithelial inoculation maintained patent tracheal lumens,which were obliterated in controls.Recipient immunosuppression facilitated the formation of an integrated ciliated epithelial layer,further demonstrated by the presence of a dense cilia population,a well-developed plasma membrane,and readily recognizable intercellular junctions.Epithelial cellular differentiation markers such as cytokeratin 14 and 18,and cystic fibrosis transmembrane conductance regulator (CFTR) were all positive in allografts under immunosuppression.Conclusion Concurrent recipient-derived epithelial inoculation with immunosuppression can result in complete reepithelialization with the recipient phenotype and suppress the luminal obliteration process in heterotopic transplantations.

  11. Induction of tolerance to cardiac allografts using donor splenocytes engineered to display on their surface an exogenous fas ligand protein.

    Science.gov (United States)

    Yolcu, Esma S; Gu, Xiao; Lacelle, Chantale; Zhao, Hong; Bandura-Morgan, Laura; Askenasy, Nadir; Shirwan, Haval

    2008-07-15

    The critical role played by Fas ligand (FasL) in immune homeostasis renders this molecule an attractive target for immunomodulation to achieve tolerance to auto- and transplantation Ags. Immunomodulation with genetically modified cells expressing FasL was shown to induce tolerance to alloantigens. However, genetic modification of primary cells in a rapid, efficient, and clinically applicable manner proved challenging. Therefore, we tested the efficacy of donor splenocytes rapidly and efficiently engineered to display on their surface a chimeric form of FasL protein (SA-FasL) for tolerance induction to cardiac allografts. The i.p. injection of ACI rats with Wistar-Furth rat splenocytes displaying SA-FasL on their surface resulted in tolerance to donor, but not F344 third-party cardiac allografts. Tolerance was associated with apoptosis of donor reactive T effector cells and induction/expansion of CD4(+)CD25(+)FoxP3(+) T regulatory (Treg) cells. Treg cells played a critical role in the observed tolerance as adoptive transfer of sorted Treg cells from long-term graft recipients into naive unmanipulated ACI rats resulted in indefinite survival of secondary Wistar-Furth grafts. Immunomodulation with allogeneic cells rapidly and efficiently engineered to display on their surface SA-FasL protein provides an effective and clinically applicable means of cell-based therapy with potential application to regenerative medicine, transplantation, and autoimmunity.

  12. Homolog of allograft inflammatory factor-1 induces macrophage migration during innate immune response in leech.

    Science.gov (United States)

    Schorn, Tilo; Drago, Francesco; Tettamanti, Gianluca; Valvassori, Roberto; de Eguileor, Magda; Vizioli, Jacopo; Grimaldi, Annalisa

    2015-03-01

    Allograft inflammatory factor-1 (AIF-1) is a 17-kDa cytokine-inducible calcium-binding protein that, in vertebrates, plays an important role in the allograft immune response. Its expression is mostly limited to the monocyte/macrophage lineage. Until recently, AIF-1 was assumed to be a novel molecule involved in inflammatory responses. To clarify this aspect, we have investigated the expression of AIF-1 after bacterial challenge and its potential role in regulating the innate immune response in an invertebrate model, the medicinal leech (Hirudo medicinalis). Analysis of an expressed sequence tag library from the central nervous system of Hirudo revealed the presence of the gene Hmaif-1/alias Hmiba1, showing high homology with vertebrate aif-1. Immunohistochemistry with an anti-HmAIF-1 polyclonal antibody revealed the constitutive presence of this protein in spread CD68(+) macrophage-like cells. A few hours after pathogen (bacterial) injection into the body wall, the amount of these immunopositive cells co-expressing HmAIF-1 and the common leucocyte marker CD45 increased at the injected site. Moreover, the recombinant protein HmAIF-1 induced massive angiogenesis and was a potent chemoattractant for macrophages. Following rHmAIF-1 stimulation, macrophage-like cells co-expressed the macrophage marker CD68 and the surface glycoprotein CD45, which, in vertebrates, seems to have a role in the integrin-mediated adhesion of macrophages and in the regulation of the functional responsiveness of cells to chemoattractants. CD45 is therefore probably involved in leech macrophage-like cell activation and migration towards an inflammation site. We have also examined its potential effect on HmAIF-1-induced signalling.

  13. Ahmedabad tolerance induction protocol and chronic renal allograft dysfunction: pathologic observations and clinical implications

    Directory of Open Access Journals (Sweden)

    Trivedi Hargovind L

    2009-01-01

    Full Text Available Abstract Background Chronic Renal Allograft Dysfunction (CRAD is responsible for a large number of graft failures. We have abrogated acute T-cell rejections using Ahmedabad Tolerance Induction Protocol (ATIP with hematopoietic stem cell transplantation (HSCT under non-myeloablative conditioning pre-transplant. However B-cell mediated rejections and CRAD continue to haunt us. We carried out retrospective analysis of renal allograft biopsies performed in the last 4 years to evaluate the effect of ATIP on CRAD. Materials and methods Biopsies diagnosed as per modified Banff criteria belonged to 2 groups: ATIP under low dose immunosuppression of cyclosporine/Azathioprine/Mycofenolate mofetil+ Prednisolone, subjected to donor leucocyte transfusion, anti-T/B cell antibodies, low dose target specific irradiation, cyclophosphamide, cyclosporin followed by HSCT pre-transplant; controls who opted out of ATIP were transplanted under standard triple drug immunosuppression. Demographics of both groups were comparable. Results Incidence of chronic changes was higher in controls (17.5% vs. 10.98% in ATIP over a mean follow up of 151.9 months in the former and 130.9 months in the latter. Proteinuria and hypertension were higher in controls (48.4% vs. ATIP (32.7% with chronic transplant glomerulopathy, focal global sclerosis in 67.7% in controls vs. 46.7% in ATIP, acute on chronic T/B cell rejection in 51.6% controls vs. 28.1% ATIP, with peritubular capillary C4d deposits in 19.4% controls vs. 1.9% ATIP biopsies. Acute on chronic calcineurin inhibitor toxicity was higher in ATIP (71.9% vs. 48.4% in controls. Conclusion Chronic immune injury was less with ATIP vs controls as compared to a higher incidence of chronic calcineurin inhibitor toxicity in the former.

  14. Ice sheet in peril

    DEFF Research Database (Denmark)

    Hvidberg, Christine Schøtt

    2016-01-01

    Earth's large ice sheets in Greenland and Antarctica are major contributors to sea level change. At present, the Greenland Ice Sheet (see the photo) is losing mass in response to climate warming in Greenland (1), but the present changes also include a long-term response to past climate transitions....... On page 590 of this issue, MacGregor et al. (2) estimate the mean rates of snow accumulation and ice flow of the Greenland Ice Sheet over the past 9000 years based on an ice sheet-wide dated radar stratigraphy (3). They show that the present changes of the Greenland Ice Sheet are partly an ongoing...... response to the last deglaciation. The results help to clarify how sensitive the ice sheet is to climate changes....

  15. Effect of Blocking with Minicircle DNA of Interleukin-6 on Skin Allograft Rejection

    Directory of Open Access Journals (Sweden)

    Doh Kyoung Chan

    2014-06-01

    Full Text Available Blocking of proinflammatory cytokine, interleukin-6 (IL-6 is effective in decreasing resistance to allogenic tolerance. In this study, we investigated whether anti-IL-6 receptor producing nonviral minicircle (MC-DNA, is competent to inhibit alloresponse-induced IL-6 in highly immunogenic murine skin allograft model. We designed MC-DNA producing IL-6R antibody and verified in vitro system. One day before skin allograft modeling, systemic MC-DNA exposed via hydrodynamic delivery of MC-DNA in vivo (50 ug of DNA, tail vein, single injection. Using GFP tagging MC-DNA, we confirmed its organ distribution. At day 5, we measured the amount of IL-6 and IL-6R antibody in serum. As functional examinations, we evaluated survival rate, morphological changes of graft, immune cell infiltration, and population of T helper 17 cells (Th17, FACS marker: CD4+/RoRγt and regulatory T cells (Treg, FACS marker: CD4+ Foxp3+. We compared its alloimmunity and graft survival efficiency with the cyclosporine A (CsA-treated group (50 mg/kg, daily administration via oral gavage. Hydrodynamic delivery of MC-DNA was mainly localized in hepatocytes. Serum IL-6 and IL-6R antibody detected in anti-IL-6R MC-DNA treated mice. At day 8.5, untreated mice completely rejected the graft confirming by daily observation of loss of skin graft and erosion. However, mice received either anti-IL-6R MC-DNA or CsA presented prolonged acceptance of graft until day 15 or 15.6, respectively. Results from morphological changes and immune cell infiltration in the graft were also consistent with survival rate. FACS results showed that anti-IL-6R MC-DNA treatment markedly suppressed Th17 population compared with the untreated mice. However, there was no effect on Treg population. On the other hand, administration of CsA showed the increased Th17 and decreased Treg population compared with untreated group. We found that single injection of nonviral minicircle DNA targeting IL-6R is effective in both

  16. Micro-organisms isolated from cadaveric samples of allograft musculoskeletal tissue.

    Science.gov (United States)

    Varettas, Kerry

    2013-12-01

    Allograft musculoskeletal tissue is commonly used in orthopaedic surgical procedures. Cadaveric donors of musculoskeletal tissue supply multiple allografts such as tendons, ligaments and bone. The microbiology laboratory of the South Eastern Area Laboratory Services (SEALS, Australia) has cultured cadaveric allograft musculoskeletal tissue samples for bacterial and fungal isolates since 2006. This study will retrospectively review the micro-organisms isolated over a 6-year period, 2006-2011. Swab and tissue samples were received for bioburden testing and were inoculated onto agar and/or broth culture media. Growth was obtained from 25.1 % of cadaveric allograft musculoskeletal tissue samples received. The predominant organisms isolated were coagulase-negative staphylococci and coliforms, with the heaviest bioburden recovered from the hemipelvis. The rate of bacterial and fungal isolates from cadaveric allograft musculoskeletal tissue samples is higher than that from living donors. The type of organism isolated may influence the suitability of the allograft for transplant.

  17. Kidney retransplantation for BK virus nephropathy with active viremia without allograft nephrectomy.

    Science.gov (United States)

    Huang, Jingbo; Danovitch, Gabriel; Pham, Phuong-Thu; Bunnapradist, Suphamai; Huang, Edmund

    2015-12-01

    BK virus nephropathy is an important cause of kidney allograft failure. Retransplantation has been successfully performed for patients with previous allograft loss due to BK virus nephropathy; however, whether allograft nephrectomy and viral clearance are required prior to retransplantation is controversial. Some recent studies have suggested that retransplantion can be successfully achieved without allograft nephrectomy if viremia is cleared prior to retransplant. The only published experience of successful retransplantation in the presence of active viremia occurred in the presence of concomitant allograft nephrectomy of the failing kidney. In this report, we describe a case of successful repeat kidney transplant in a patient with high-grade BK viremia and fulminant hepatic failure without concomitant allograft nephrectomy performed under the setting of a simultaneous liver-kidney transplant.

  18. High Sensitive and Selective Sensing of Hydrogen Peroxide Released from Pheochromocytoma Cells Based on Pt-Au Bimetallic Nanoparticles Electrodeposited on Reduced Graphene Sheets

    Directory of Open Access Journals (Sweden)

    Guangxia Yu

    2015-01-01

    Full Text Available In this study, a high sensitive and selective hydrogen peroxide (H2O2 sensor was successfully constructed with Pt-Au bimetallic nanoparticles (Pt-Au NPs/reduced graphene sheets (rGSs hybrid films. Various molar ratios of Au to Pt and different electrodeposition conditions were evaluated to control the morphology and electrocatalytic activity of the Pt-Au bimetallic nanoparticles. Upon optimal conditions, wide linear ranges from 1 µM to 1.78 mM and 1.78 mM to 16.8 mM were obtained, with a detection limit as low as 0.31 µM. Besides, due to the synergetic effects of the bimetallic NPs and rGSs, the amperometric H2O2 sensor could operate at a low potential of 0 V. Under this potential, not only common anodic interferences induced from ascorbic acid, uric acid and dopamine, but also the cathodic interference induced from endogenous O2 could be effectively avoided. Furthermore, with rat pheochromocytoma cells (PC 12 as model, the proposed sensor had been successfully used in the detection of H2O2 released from the cancer cells. This method with wide linear ranges and excellent selectivity can provide a promising alternative for H2O2 monitoring in vivo in the fields of physiology, pathology and diagnosis.

  19. Enzymes for Pancreatic Islet Isolation Impact Chemokine-Production and Polarization of Insulin-Producing β-Cells with Reduced Functional Survival of Immunoisolated Rat Islet-Allografts as a Consequence.

    Science.gov (United States)

    de Vos, Paul; Smink, Alexandra M; Paredes, Genaro; Lakey, Jonathan R T; Kuipers, Jeroen; Giepmans, Ben N G; de Haan, Bart J; Faas, Marijke M

    2016-01-01

    The primary aim of this study was to determine whether normal variations in enzyme-activities of collagenases applied for rat-islet isolation impact longevity of encapsulated islet grafts. Also we studied the functional and immunological properties of rat islets isolated with different enzyme preparations to determine whether this impacts these parameters. Rat-islets were isolated from the pancreas with two different collagenases with commonly accepted collagenase, neutral protease, and clostripain activities. Islets had a similar and acceptable glucose-induced insulin-release profile but a profound statistical significant difference in production of the chemokines IP-10 and Gro-α. The islets were studied with nanotomy which is an EM-based technology for unbiased study of ultrastructural features of islets such as cell-cell contacts, endocrine-cell condition, ER stress, mitochondrial conditions, and cell polarization. The islet-batch with higher chemokine-production had a lower amount of polarized insulin-producing β-cells. All islets had more intercellular spaces and less interconnected areas with tight cell-cell junctions when compared to islets in the pancreas. Islet-graft function was studied by implanting encapsulated and free islet grafts in rat recipients. Alginate-based encapsulated grafts isolated with the enzyme-lot inducing higher chemokine production and lower polarization survived for a two-fold shorter period of time. The lower survival-time of the encapsulated grafts was correlated with a higher influx of inflammatory cells at 7 days after implantation. Islets from the same two batches transplanted as free unencapsulated-graft, did not show any difference in survival or function in vivo. Lack of insight in factors contributing to the current lab-to-lab variation in longevity of encapsulated islet-grafts is considered to be a threat for clinical application. Our data suggest that seemingly minor variations in activity of enzymes applied for islet

  20. The cholinergic anti-inflammatory pathway delays TLR-induced skin allograft rejection in mice: cholinergic pathway modulates alloreactivity.

    Directory of Open Access Journals (Sweden)

    Claude Sadis

    Full Text Available Activation of innate immunity through Toll-like receptors (TLR can abrogate transplantation tolerance by revealing hidden T cell alloreactivity. Separately, the cholinergic anti-inflammatory pathway has the capacity to dampen macrophage activation and cytokine release during endotoxemia and ischemia reperfusion injury. However, the relevance of the α7 nicotinic acetylcholine receptor (α7nAChR-dependent anti-inflammatory pathway in the process of allograft rejection or maintenance of tolerance remains unknown. The aim of our study is to investigate whether the cholinergic pathway could impact T cell alloreactivity and transplant outcome in mice. For this purpose, we performed minor-mismatched skin allografts using donor/recipient combinations genetically deficient for the α7nAChR. Minor-mismatched skin grafts were not rejected unless the mice were housed in an environment with endogenous pathogen exposure or the graft was treated with direct application of imiquimod (a TLR7 ligand. The α7nAChR-deficient recipient mice showed accelerated rejection compared to wild type recipient mice under these conditions of TLR activation. The accelerated rejection was associated with enhanced IL-17 and IFN-γ production by alloreactive T cells. An α7nAChR-deficiency in the donor tissue facilitated allograft rejection but not in recipient mice. In addition, adoptive T cell transfer experiments in skin-grafted lymphopenic animals revealed a direct regulatory role for the α7nAChR on T cells. Taken together, our data demonstrate that the cholinergic pathway regulates alloreactivity and transplantation tolerance at multiple levels. One implication suggested by our work is that, in an organ transplant setting, deliberate α7nAChR stimulation of brain dead donors might be a valuable approach for preventing donor tissue inflammation prior to transplant.

  1. The cholinergic anti-inflammatory pathway delays TLR-induced skin allograft rejection in mice: cholinergic pathway modulates alloreactivity.

    Science.gov (United States)

    Sadis, Claude; Detienne, Sophie; Vokaer, Benoît; Charbonnier, Louis-Marie; Lemaître, Philippe; Spilleboudt, Chloé; Delbauve, Sandrine; Kubjak, Carole; Flamand, Véronique; Field, Kenneth A; Goldman, Michel; Benghiat, Fleur S; Le Moine, Alain

    2013-01-01

    Activation of innate immunity through Toll-like receptors (TLR) can abrogate transplantation tolerance by revealing hidden T cell alloreactivity. Separately, the cholinergic anti-inflammatory pathway has the capacity to dampen macrophage activation and cytokine release during endotoxemia and ischemia reperfusion injury. However, the relevance of the α7 nicotinic acetylcholine receptor (α7nAChR)-dependent anti-inflammatory pathway in the process of allograft rejection or maintenance of tolerance remains unknown. The aim of our study is to investigate whether the cholinergic pathway could impact T cell alloreactivity and transplant outcome in mice. For this purpose, we performed minor-mismatched skin allografts using donor/recipient combinations genetically deficient for the α7nAChR. Minor-mismatched skin grafts were not rejected unless the mice were housed in an environment with endogenous pathogen exposure or the graft was treated with direct application of imiquimod (a TLR7 ligand). The α7nAChR-deficient recipient mice showed accelerated rejection compared to wild type recipient mice under these conditions of TLR activation. The accelerated rejection was associated with enhanced IL-17 and IFN-γ production by alloreactive T cells. An α7nAChR-deficiency in the donor tissue facilitated allograft rejection but not in recipient mice. In addition, adoptive T cell transfer experiments in skin-grafted lymphopenic animals revealed a direct regulatory role for the α7nAChR on T cells. Taken together, our data demonstrate that the cholinergic pathway regulates alloreactivity and transplantation tolerance at multiple levels. One implication suggested by our work is that, in an organ transplant setting, deliberate α7nAChR stimulation of brain dead donors might be a valuable approach for preventing donor tissue inflammation prior to transplant.

  2. Septic arthritis following anterior cruciate ligament reconstruction using tendon allografts--Florida and Louisiana, 2000.

    Science.gov (United States)

    2001-12-01

    In the United States, approximately 50,000 knee surgeries are performed each year for repairing anterior cruciate ligament (ACL) injuries. Tissue allografts frequently are used for ACL reconstruction, and septic arthritis is a rare complication of such procedures. This report describes four patients who acquired postsurgical septic arthritis probably associated with contaminated bone-tendon-bone allografts used for ACL reconstruction. Effective sterilization methods that do not functionally alter musculoskeletal tissue are needed to prevent allograft-related infections.

  3. Transforming growth factor-β1 short hairpin RNA inhibits renal allograft fibrosis

    Institute of Scientific and Technical Information of China (English)

    YIN Zhi-kang; WU Xiao-hou; XIA Yu-guo; LUO Chun-li

    2011-01-01

    Background Transforming growth factor-β1 (TGF-β1) is known to be a key fibrogenic cytokine in a number of chronic fibrotic diseases, including chronic allograft nephropathy. We examined the effects of inhibition of TGF-β1 expression by RNA interference on renal allograft fibrosis, and explored the mechanisms responsible for these effects.Methods A Sprague-Dawley-to-Wistar rat model of accelerated kidney transplant fibrosis was used. Sixty recipient adult Wistar rats were randomly divided into four groups: group T (sham-operated group), group T (plasmid-transfected group), group H (control plasmid group), and group Y (transplant only group). Rats in group T were transfected with 200μg of TGF-β1 short hairpin RNA (shRNA). Reverse transcription-polymerase chain reaction and Western blotting were used to examine the expression of TGF-β1, Smad3/7, E-cadherin, and type I collagen. The distribution of type I collagen was measured by immunohistochemistry. The pathologic changes and extent of fibrosis were assessed by hematoxylin and eosin and Masson staining. E-cadherin and α-smooth muscle actin immunohistochemical staining were used to label tubular epithelial cells and fibroblasts, respectively.Results Plasmid transfection significantly inhibited the expression of TGF-β1, as well as that of its target gene, type I collagen (P <0.05 and P <0.01, respectively). In addition, the degree of fibrosis was mild, and its development was delayed in plasmid-transfected rats. In contrast, TGF-β1-shRNA transfection maintained the expression of E-cadherin in tubular epithelial cells while it inhibited the transformation from epithelial cells to fibroblasts. Blood urea nitrogen and serum creatinine were lower in the plasmid group than in the control groups (P <0.05 and P<0.01, respectively).Conclusions This study suggests that transfection of a TGF-β1-shRNA plasmid could inhibit the fibrosis of renal allografts. The mechanism may be associated with the downregulation

  4. A single apheresis procedure in the donor may be enough to complete an allograft using the “Mexican Method” of non-ablative allografting

    Science.gov (United States)

    Ruiz-Delgado, Guillermo J.; Gutiérrez-Riveroll, Karla I.; Gutiérrez-Aguirre, César H.; Gómez-Almaguer, David; Eyzaguirre-Zapata, Renee; Priesca-Marin, Manuel; González-Carrillo, Martha L.; Ruiz-Argüelles, Guillermo J.

    2009-01-01

    Background Since 1999, in Mexico we have been using a regimen to conduct allografts that involves non-myeloablative conditioning and peripheral blood stem cells (PBSC) and have introduced some changes with the main goal of decreasing the cost of the procedure. Materials and methods We analysed the salient apheresis features of a group of 175 allogeneic peripheral blood stem cell transplants conducted in two institutions in a 7-year period. The grafts were conducted using the “Mexican” non-myelo ablative conditioning regimen employing oral busulphan, i.v. cyclophosphamide and i.v. fludarabine. In all instances, the apheresis machine employed was the Baxter CS3000 Plus and donors were mobilised with filgrastim. The apheresis procedures were performed on days 0, +1 and +2, the end-point of collection being 5,000 mL of blood/m2 in each procedure. Three apheresis sessions were planned but the number was adjusted according to the cell yield. Results The final number of allografted CD34 cells ranged between 0.5 and 25.4 × 106/Kg of the recipient’s body weight (median, 5.2 × 106/Kg). One to three apheresis procedures were needed to obtain a product containing more than 0.5 × 106 CD34 cells/Kg of the recipient, the median being two procedures; in 72 cases (41%) a single apheresis procedure was sufficient to obtain the target number of CD34 cells. The volumes of apheresis ranged between 50 and 600 mL (median, 400 mL). Conclusions Since the median cost of each apheresis procedure is 900 USD, the fact that two apheresis procedures was spared in 72 cases and one apheresis was spared in another 65 cases, led to a total saving of approximately 188,100 USD. It can be concluded that, in many cases, allogeneic transplants can be completed with a single apheresis session and that there are considerable financial benefits from this practice. PMID:19503634

  5. Quantification of renal allograft perfusion using arterial spin labeling MRI: initial results

    Energy Technology Data Exchange (ETDEWEB)

    Lanzman, Rotem S.; Wittsack, Hans-Joerg; Bilk, Philip; Kroepil, Patric; Blondin, Dirk [University Hospital Duesseldorf, Department of Radiology, Duesseldorf (Germany); Martirosian, Petros; Schick, Fritz [University Hospital Tuebingen, Section for Experimental Radiology, Department of Diagnostic Radiology, Tuebingen (Germany); Zgoura, Panagiota; Voiculescu, Adina [University Hospital Duesseldorf, Department of Nephrology, Duesseldorf (Germany)

    2010-06-15

    To quantify renal allograft perfusion in recipients with stable allograft function and acute decrease in allograft function using nonenhanced flow-sensitive alternating inversion recovery (FAIR)-TrueFISP arterial spin labeling (ASL) MR imaging. Following approval of the local ethics committee, 20 renal allograft recipients were included in this study. ASL perfusion measurement and an anatomical T2-weighted single-shot fast spin-echo (HASTE) sequence were performed on a 1.5-T scanner (Magnetom Avanto, Siemens, Erlangen, Germany). T2-weighted MR urography was performed in patients with suspected ureteral obstruction. Patients were assigned to three groups: group a, 6 patients with stable allograft function over the previous 4 months; group b, 7 patients with good allograft function who underwent transplantation during the previous 3 weeks; group c, 7 allograft recipients with an acute deterioration of renal function. Mean cortical perfusion values were 304.8 {+-} 34.4, 296.5 {+-} 44.1, and 181.9 {+-} 53.4 mg/100 ml/min for groups a, b and c, respectively. Reduction in cortical perfusion in group c was statistically significant. Our results indicate that ASL is a promising technique for nonenhanced quantification of cortical perfusion of renal allografts. Further studies are required to determine the clinical value of ASL for monitoring renal allograft recipients. (orig.)

  6. 21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

    Science.gov (United States)

    2010-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system....

  7. Remodeling of cortical bone allografts mediated by adherent rAAV-RANKL and VEGF gene therapy

    DEFF Research Database (Denmark)

    Ito, Hiromu; Koefoed, Mette; Tiyapatanaputi, Prarop

    2005-01-01

    Structural allograft healing is limited because of a lack of vascularization and remodeling. To study this we developed a mouse model that recapitulates the clinical aspects of live autograft and processed allograft healing. Gene expression analyses showed that there is a substantial decrease...... in the genes encoding RANKL and VEGF during allograft healing. Loss-of-function studies showed that both factors are required for autograft healing. To determine whether addition of these signals could stimulate allograft vascularization and remodeling, we developed a new approach in which rAAV can be freeze...

  8. MR evaluation of renal allografts; Rola badania MR w ocenie nerki przeszczepionej

    Energy Technology Data Exchange (ETDEWEB)

    Slapa, R.Z.; Jakubowski, W.; Tyminska, B. [Zaklad Diagnostyki Obrazowej, Wojewodzki Zespol Publicznych Zakladow Opieki Zdrowotnej, Warsaw (Poland)

    1994-12-31

    The paper presents state of the art in MR evaluation of renal allografts. MRI is very sensitive in diagnosis of renal allograft rejection. This diagnosis is mainly based on evaluation of cortico-medullary differentiation. MRI has potential for differential diagnosis of pathological perirental fluid collections. T2-weighted images and paramagnetic contrast agent studies diagnosis of allograft necrosis. MRA is useful for evaluation of possible vascular surgical complications. New applications of MR technique for evaluation of renal allograft as dynamic contrast agent studies and spectroscopy are under investigation. (author) 15 refs, 2 figs

  9. Impaired renal allograft function is associated with increased arterial stiffness in renal transplant recipients

    DEFF Research Database (Denmark)

    Kneifel, M; Scholze, A; Burkert, A;

    2006-01-01

    It is important whether impairment of renal allograft function may deteriorate arterial stiffness in renal transplant recipients. In a cross-sectional study, arterial vascular characteristics were non-invasively determined in 48 patients with renal allograft using applanation tonometry and digital...... of large arteries S1 and small arteries S2 in renal transplant recipients (each p renal allograft (p ...-Wallis test between groups). It is concluded that impairment of renal allograft function is associated with an increased arterial stiffness in renal transplant recipients....

  10. Late Acute Rejection Occuring in Liver Allograft Recipients

    Directory of Open Access Journals (Sweden)

    Eric M Yoshida

    1996-01-01

    Full Text Available To study the effect of immunosuppressive reduction on the incidence and consequence of late acute rejection (LAR in liver allograft recipients, mean daily prednisone dose, mean cyclosporine A (CsA trough and nadir levels were retrospectively reviewed for the nearest 12-week period preceding six episodes of LAR in five liver allograft recipients (group 1. Results were compared with those from a cohort of 12 liver allograft recipients who did not develop LAR (group 2. LAR was defined as acute rejection occurring more than 365 days post-transplantation. Median follow-up for both groups was similar (504 days, range 367 to 1050, versus 511 days, range 365 to 666, not significant. Mean trough CsA levels were lower in patients with LAR compared with those without (224±66 ng/mL versus 233±49 ng/mL but the difference was not statistically significant. In contrast, mean daily prednisone dose (2.5±1.6 mg/ day versus 6.5±2.9 mg/day, P=0.007 and CsA nadir values (129±60 ng/mL versus 186±40 ng/mL, P=0.03 were significantly lower in patients who developed LAR compared with those who did not. Five of six episodes (83% of LAR occurred in patients receiving less than 5 mg/day of prednisone, versus a single LAR episode in only one of 12 patients (8% receiving prednisone 5 mg/day or more (P=0.004. In all but one instance, LAR responded to pulse methylprednisolone without discernible affect on long term graft function. The authors conclude that liver allograft recipients remain vulnerable to acute rejection beyond the first post-transplant year; and reduction of immunosuppressive therapy, particularly prednisone, below a critical, albeit low dose, threshold increases the risk of LAR.

  11. Treatment of chronic osteomyelitis with one-stage allograft

    Institute of Scientific and Technical Information of China (English)

    LU Wei-ju; LI Bin; BAO Ni-rong; QIAN Hong-bo; ZENG Xiao-feng; XU Bin; CHEN Yong; ZHAO Jian-ning

    2006-01-01

    Objective: To avoid disadvantages of two-stage cancellus bone autograft, we investigated the feasibility of one-stage allograft for reconstructing the bone defect resulting from debridement of chronic osteomyelitis in limbs.Methods: Between Feb. 1999 and Apr. 2004, 35 cases of chronic osteomyelitis (8 cases of nonunion )underwent one-stage allograft after debridement in our hospital.Results: Thirty-five cases were followed up for an average period of 28 months (range, 13 to 55 months), in which 32 cases (91.43%) were found no infection, and 3cases (8.57 %) were confirmed recurrence of infection.Four out of 8 cases of bone nonunion healed in 9.5 months on average (range, 3 to 12 months), and another case also acquired union after redebridement and autograft of ilium due to infection recurrence 35 days after surgery.Renonunion occurred in 3 cases, 2 out of whom healed after secondary operation with autograft. One case of renonunion and 2 cases of infection recurrence refused further treatment.Conclusions: A high rate of infection arrest can be attained when one-stage allograft is used to reconstruct the bone defect of chronic osteomyelitis after debridement in limbs. Therefore, chronic osteomyelitis should not be regarded as a contraindication to one-stage allogeneic bone grafting. Renonuion, however, achieves a relatively high rate, especially in cases of segmental bone defect.

  12. Multidetector computed tomography findings of spontaneous renal allograft ruptures

    Energy Technology Data Exchange (ETDEWEB)

    Basaran, C. [Department of Radiology, Baskent University Faculty of Medicine, Ankara (Turkey)], E-mail: ceylab@baskent-ank.edu.tr; Donmez, F.Y.; Tarhan, N.C.; Coskun, M. [Department of Radiology, Baskent University Faculty of Medicine, Ankara (Turkey); Haberal, M. [Department of General Surgery, Baskent University Faculty of Medicine, Ankara (Turkey)

    2009-05-15

    Aim: To describe the characteristics of spontaneous renal allograft rupture using multidetector computed tomography (MDCT). Method: Five patients with spontaneous renal allograft rupture, as confirmed by pathologic examination, were referred to our institution between 1985 and 2008. The clinical records and preoperative MDCT findings of the patients were studied retrospectively. Results: Clinical and/or histological findings were consistent with acute rejection in all cases. Using MDCT, disruption of the capsular integrity and parenchymal rupture was seen in four patients. Four of the five patients showed decreased enhancement and swollen grafts. Perirenal (n = 4), subcapsular (n = 1), and intraparenchymal (n = 1) haematomas were also seen. In the patient with an intraparenchymal haematoma there was no disruption of capsular integrity, but capsular irregularities were seen near the haematoma. Conclusion: MDCT is a useful investigative tool for the evaluation of suspected spontaneous renal allograft rupture. As well as a swollen graft, disruption of the capsule, parenchyma, and/or haematoma should prompt the radiologist to consider this diagnosis.

  13. Renal allograft tuberculosis with infected lymphocele transmitted from the donor.

    Science.gov (United States)

    Al-Nesf, Maryam Ali; Al-Ani, Omar Isam; Al-Ani, Ahmed Abdul-Rahman; Rashed, Awad Hamed

    2014-03-01

    Transmission of tuberculosis (TB) from a donor through renal transplantation is a rare incident. We are reporting a 53-year-old Qatari woman diagnosed with renal allograft TB infection. The disease was confirmed by isolation of Mycobacterium tuberculosis from fluid from the lymphocele and demonstration of caseating granuloma in graft biopsy with acid-fast bacilli seen on Ziehl-Neelsen staining. The diagnosis was made quite early post-transplantation. The presence of the granuloma, which is unusual with patients on intensive immunosuppressant medications, suggests that transmission of the infection occurred from the donor rather than from the activation of latent infection. In reviewing the literature, we found ten case reports of TB in transplanted kidney with transmission of TB infection from the donor. The presence of TB in lymphocele in association with the infected transplant by TB, to the best of our knowledge, was reported only once in the literature. Our case had unfavorable outcome and ended by renal allograft nephrectomy and hemodialysis. We are presenting this case of TB infection of renal allograft and lymphocele diagnosed early post-transplantation transmitted from the donor and pertinent review from the literature.

  14. Significance of urinary proteome pattern in renal allograft recipients.

    Science.gov (United States)

    Suhail, Sufi M

    2014-01-01

    Urinary proteomics is developing as a platform of urinary biomarkers of immense potential in recent years. The definition of urinary proteome in the context of renal allograft and characterization of different proteome patterns in various graft dysfunctions have led to the development of a distinct science of this noninvasive tool. Substantial numbers of studies have shown that different renal allograft disease states, both acute and chronic, could portray unique urinary proteome pattern enabling early diagnosis of graft dysfunction and proper manipulation of immunosuppressive strategy that could impact graft prognosis. The methodology of the urinary proteome is nonetheless not more complex than that of other sophisticated assays of conventional urinary protein analysis. Moreover, the need for a centralized database is also felt by the researchers as more and more studies have been presenting their results from different corners and as systems of organizing these newly emerging data being developed at international and national levels. In this context concept of urinary proteomics in renal allograft recipients would be of significant importance in clinical transplantation.

  15. Thermoforming of foam sheet

    NARCIS (Netherlands)

    Akkerman, Remko; Pronk, Ruud M.

    1997-01-01

    Thermoforming is a widely used process for the manufacture of foam sheet products. Polystyrene foam food trays for instance can be produced by first heating the thermoplastic foam sheet, causing the gas contained to build up pressure and expand, after which a vacuum pressure can be applied to draw t

  16. S108抑制大鼠肾移植排斥反应时细胞间粘附分子-1的表达%S108 inhibits the expression of cell adhesion molecule-1 (ICAM-1) during the rejection of renal allograft in rat

    Institute of Scientific and Technical Information of China (English)

    沈文律; 黄孝伦; 周泽清; 李幼平; 王学; 杜成友

    1998-01-01

    观测细胞间粘附分子-1(ICAM-1)在大鼠移植肾的表达,旨在探索S108抗排斥作用的机理以及对ICAM-1的表达有无抑制作用.共分5个实验组:即同品系移植组、不用药对照组、短期单用环孢素A(CsA)组、小剂量CsA联合S108组及单用S108组.采用小鼠抗大鼠单克隆抗体(IA29)测定移植肾内ICAM-1的表达,每一标本采用计算机图象分析定量测定.结果表明,ICAM-1在同品系移植肾肾小管周围的毛细血管内皮细胞、静脉和肾小管仅呈微弱阳性表达,不表达于肾间质组织.排斥时ICAM-1在移植肾血管内皮细胞、组织间质和肾小管上广泛表达,表达水平高低与移植肾排斥强弱有相关性,S108可降低ICAM-1抗原分子在移植肾的表达水平,呈现抗排斥效应.%In order to explore the anti-rejection mechanism of S108 and its inhibition on the ICAM-1 expression, the "expression of ICAM-1 in rat renal isografts and allografts was studied.The rats were divided into 5 experimental groups. The expression of ICAM-1 in the renal grafts was determined using mouse anti-rat monoclonal antibody (IA29). Quantitative measurement was performed in each samples using computer imaging analysis. The results showed that the expression of ICAM-1 presented faint positive inthe capillary endothelial cells, veins around the tubules and the tubules in the same strain renal grafts. No ICAM-1 expression was found in the renal intestitial tissue. The extensive expression of ICAM-1 was found in the endothelial cells, intestitial tissue and tubules of the renal grafts during the rejection with the expression level relative to the severity of the rejection of the renal grafts. S108 could reduce the expression level of ICAM-1 in the renal grafts, so as to present anti-rejection reaction.

  17. 未成熟树突状细胞抑制高危角膜移植免疫排斥反应的实验研究%Experimental study of donor-derived immature dendritic cells inhibiting high-risk corneal allograft rejection

    Institute of Scientific and Technical Information of China (English)

    付燕; 高晓唯

    2013-01-01

    Objective To culture and induce the rat bone marrow-derived dendrtic cells,investigate the suppressive effects of immature dendritic cells on high-risk corneal allograft rejection.Methods To cultivate,induce and amplify a large number of dendritic cells,with morphological observation,immunological phenotype identification by flow cytometry; 45 Wistar and 23 SD rats were used as donors and recipients respectively to establish allogeneic risk corneal transplantation model with alkaline burn.The SD rats were randomly divided into control group with 15 rats,immature dendritic cells (imDC) group with 15 rats and mature dendritic cells (mDC) group with 15 rats.In control group,0.1 ml Phosphate buffer were injected into SD rats via tail vein in 7th day before corneal transplantation; In imDC group,donor bone marrow-derived imDC of 1 × 106 were injected into SD rats via tail vein in 7th day before corneal transplantation; In mDC group,donor bone marrow-derived mDC of 1 × 106 were injected into SD rats via tail vein in 7th day before corneal transplantation.The survival of corneal graft were observed and scored by slitlamp microscope everyday after transplantation.In each group,five recipients were killed on 14th day after transplantation,the corneal grafts were take and fixed in 10% formaldehyde solution for hematoxylin-eosin(HE) staining.Results With combination of rat lymphocyte separation medium induced a large number of dendritic cells,the dendritic cells were proved in different state with morphological observation by inverted phase contrast microscope and scanning electron microseope,with immunological phenotype indentification by flow cytometry.The mean survival time of corneal graft was 19.6 + 1.1 days in imDC group,9.5 ± 0.9 days in control group and 7 ± 1.6 days in mDC group.The differences were statistically significant.Conclusions The imDC from donor in vitro culture can suppress high-risk corneal allograft rejection in rat.%目的 培养和诱导大鼠

  18. Mechanics of Sheeting Joints

    Science.gov (United States)

    Martel, S. J.

    2015-12-01

    Physical breakdown of rock across a broad scale spectrum involves fracturing. In many areas large fractures develop near the topographic surface, with sheeting joints being among the most impressive. Sheeting joints share many geometric, textural, and kinematic features with other joints (opening-mode fractures) but differ in that they are (a) discernibly curved, (b) open near the topographic surface, and (c) form subparallel to the topographic surface. Where sheeting joints are geologically young, the surface-parallel compressive stresses are typically several MPa or greater. Sheeting joints are best developed beneath domes, ridges, and saddles; they also are reported, albeit rarely, beneath valleys or bowls. A mechanism that accounts for all these associations has been sought for more than a century: neither erosion of overburden nor high lateral compressive stresses alone suffices. Sheeting joints are not accounted for by Mohr-Coulomb shear failure criteria. Principles of linear elastic fracture mechanics, together with the mechanical effect of a curved topographic surface, do provide a basis for understanding sheeting joint growth and the pattern sheeting joints form. Compressive stresses parallel to a singly or doubly convex topographic surface induce a tensile stress perpendicular to the surface at shallow depths; in some cases this alone could overcome the weight of overburden to open sheeting joints. If regional horizontal compressive stresses, augmented by thermal stresses, are an order of magnitude or so greater than a characteristic vertical stress that scales with topographic amplitude, then topographic stress perturbations can cause sheeting joints to open near the top of a ridge. This topographic effect can be augmented by pressure within sheeting joints arising from water, ice, or salt. Water pressure could be particularly important in helping drive sheeting joints downslope beneath valleys. Once sheeting joints have formed, the rock sheets between

  19. 化学去细胞异体神经周围复合BMSCs生物蛋白胶复合物促周围神经缺损修复%EFFECT OF CHEMICAL EXTRACTED ACELLULAR NERVE ALLOGRAFT SUPPLEMENTING WITH BONE MARROW MESENCHYMAL STEM CELLS EMBEDDED IN FIBRIN GLUE ON FUNCTIONAL RECOVERY OF TRANSECTED SCIATIC NERVES

    Institute of Scientific and Technical Information of China (English)

    赵喆; 许文静; 卢世璧; 王玉; 彭江; 赵斌; 赵庆; 刘炎; 任志午; 詹胜峰; 张莉

    2011-01-01

    目的 将BMSCs复合在化学去细胞异体神经(chemical extracted acellular nerve allograft,CEANA)周围,观察对CEANA修复周围神经缺损效果的影响.方法 成年雄性C57小鼠21只,体重25~30 g;成年雄性Balb/c小鼠15只,体重25~30 g.取Balb/c小鼠双侧坐骨神经,制备CEANA.取C57小鼠3只,分离培养BMSCs,取5 x 106个第3代BMSCs添加到500μL生物蛋白胶制备BMSCs生物蛋白胶复合物,共培养3、7、14、21 d后,分别取其上清与PC12细胞共培养,观察对PC12细胞的影响.取成年雄性C57小鼠18只,制备小鼠左侧坐骨神经10mm缺损模型,随机分成3组(n=6),分别采用自体神经移植复合生物蛋白胶(A组)、CEANA移植复合BMSCs生物蛋白胶复合物(B组)、CEANA移植复合生物蛋白胶(C组)修复坐骨神经缺损;实验动物右侧切开暴露坐骨神经,作为正常对照.术后行大体观察;术前及术后2、4、6、8周测量小鼠坐骨神经指数(static sciatic index,SSI);术后8周取材计算术侧小腿三头肌湿重恢复率并行小腿三头肌Masson染色观察,吻合口远端神经行甲苯胺蓝染色和透射电镜观察.结果 BMSCs在生物蛋白胶内均匀分布,外观呈球形,培养3d后可见BMSCs呈多个长突起.加入BMSCs生物蛋白胶复合物共培养3、7、14、21 d的上清,PC12细胞均分化为类神经元样细胞.术后各组动物切口愈合良好.各组SSI随时间延长逐渐增加,术后4、6、8周A组SSI均高于B、C组,差异有统计学意义(P0.05).术后8周,B组小腿三头肌湿重恢复率、有髓神经纤维总数均优于C组,但较A组差,差异有统计学意义(P0.05).结论 在CEANA周围添加BMSCs生物蛋白胶复合物可提高周围神经损伤修复效果.%Objective To investigate the effect of bone marrow mesenchymal stem cells (BMSCs) embedded in fibrin glue around chemical extracted acellular nerve allograft (CEANA) on the peripheral nerve regeneration. Methods Twenty-one adult male C57 mice (weighing 25-30 g

  20. Scaffold Sheet Design Strategy for Soft Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Liping Tang

    2010-02-01

    Full Text Available Creating heterogeneous tissue constructs with an even cell distribution and robust mechanical strength remain important challenges to the success of in vivo tissue engineering. To address these issues, we are developing a scaffold sheet tissue engineering strategy consisting of thin (~200 μm, strong, elastic, and porous crosslinked urethane- doped polyester (CUPE scaffold sheets that are bonded together chemically or through cell culture. Suture retention of the tissue constructs (four sheets fabricated by the scaffold sheet tissue engineering strategy is close to the surgical requirement (1.8 N rendering their potential for immediate implantation without a need for long cell culture times. Cell culture results using 3T3 fibroblasts show that the scaffold sheets are bonded into a tissue construct via the extracellular matrix produced by the cells after 2 weeks of in vitro cell culture.

  1. Dielectric and diffusion barrier multilayer for Cu(In,Ga)Se{sub 2} solar cells integration on stainless steel sheet

    Energy Technology Data Exchange (ETDEWEB)

    Amouzou, Dodji, E-mail: dodji.amouzou@fundp.ac.be [Research Centre in Physics of Matter and Radiation (PMR), University of Namur (FUNDP), Rue de Bruxelles, 61, 5000 Namur (Belgium); Guaino, Philippe; Fourdrinier, Lionel; Richir, Jean-Baptiste; Maseri, Fabrizio [CRM-Group, Boulevard de Colonster, B 57, 4000 Liège (Belgium); Sporken, Robert [Research Centre in Physics of Matter and Radiation (PMR), University of Namur (FUNDP), Rue de Bruxelles, 61, 5000 Namur (Belgium)

    2013-09-02

    For the fabrication of monolithically integrated flexible Cu(In, Ga)Se{sub 2}, CIGS modules on stainless steel, individual photovoltaic cells must be insulated from metal substrates by a barrier layer that can sustain high thermal treatments. In this work, a combination of sol–gel (organosilane-sol) and sputtered SiAlxOy forming thin diffusion barrier layers (TDBL) was prepared on stainless steel substrates. The deposition of organosilane-sol dielectric layers on the commercial stainless steel (maximal roughness, Rz = 500 nm and Root Mean Square roughness, RMS = 56 nm) induces a planarization of the surface (RMS = 16.4 nm, Rz = 176 nm). The DC leakage current through the dielectric layers was measured for the metal-insulator-metal (MIM) junctions that act as capacitors. This method allowed us to assess the quality of our TDBL insulating layer and its lateral uniformity. Indeed, evaluating a ratio of the number of valid MIM capacitors to the number of tested MIM capacitors, a yield of ∼ 95% and 50% has been reached respectively with non-annealed and annealed samples based on sol–gel double layers. A yield of 100% was achieved for sol–gel double layers reinforced with a sputtered SiAlxOy coating and a third sol–gel monolayer. Since this yield is obtained on several samples, it can be extrapolated to any substrate size. Furthermore, according to Glow Discharge Optical Emission Spectroscopy and Time of Flight Secondary Ion Mass Spectroscopy measurements, these barrier layers exhibit excellent barrier properties against the diffusion of undesired atoms which could otherwise spoil the electronic and optical properties of CIGS photovoltaic cells. - Highlights: • We functionalize steel for monolithically integrated Cu(In,Ga)Se{sub 2} solar cells • Thin dielectric and diffusion barrier layers (TDDBL) prepared on steel • Reliability and breakdown voltage of dielectric layers have been studied. • Investigation of thermal treatment effect on dielectric

  2. Human leukocyte antigen supertype matching after myeloablative hematopoietic cell transplantation with 7/8 matched unrelated donor allografts: a report from the Center for International Blood and Marrow Transplant Research

    Science.gov (United States)

    Lazaryan, Aleksandr; Wang, Tao; Spellman, Stephen R.; Wang, Hai-Lin; Pidala, Joseph; Nishihori, Taiga; Askar, Medhat; Olsson, Richard; Oudshoorn, Machteld; Abdel-Azim, Hisham; Yong, Agnes; Gandhi, Manish; Dandoy, Christopher; Savani, Bipin; Hale, Gregory; Page, Kristin; Bitan, Menachem; Reshef, Ran; Drobyski, William; Marsh, Steven GE; Schultz, Kirk; Müller, Carlheinz R.; Fernandez-Viña, Marcelo A.; Verneris, Michael R.; Horowitz, Mary M.; Arora, Mukta; Weisdorf, Daniel J.; Lee, Stephanie J.

    2016-01-01

    The diversity of the human leukocyte antigen (HLA) class I and II alleles can be simplified by consolidating them into fewer supertypes based on functional or predicted structural similarities in epitope-binding grooves of HLA molecules. We studied the impact of matched and mismatched HLA-A (265 versus 429), -B (230 versus 92), -C (365 versus 349), and -DRB1 (153 versus 51) supertypes on clinical outcomes of 1934 patients with acute leukemias or myelodysplasia/myeloproliferative disorders. All patients were reported to the Center for International Blood and Marrow Transplant Research following single-allele mismatched unrelated donor myeloablative conditioning hematopoietic cell transplantation. Single mismatched alleles were categorized into six HLA-A (A01, A01A03, A01A24, A02, A03, A24), six HLA-B (B07, B08, B27, B44, B58, B62), two HLA-C (C1, C2), and five HLA-DRB1 (DR1, DR3, DR4, DR5, DR9) supertypes. Supertype B mismatch was associated with increased risk of grade II–IV acute graft-versus-host disease (hazard ratio =1.78, P=0.0025) compared to supertype B match. Supertype B07-B44 mismatch was associated with a higher incidence of both grade II–IV (hazard ratio=3.11, P=0.002) and III–IV (hazard ratio=3.15, P=0.01) acute graft-versus-host disease. No significant associations were detected between supertype-matched versus -mismatched groups at other HLA loci. These data suggest that avoiding HLA-B supertype mismatches can mitigate the risk of grade II–IV acute graft-versus-host disease in 7/8-mismatched unrelated donor hematopoietic cell transplantation when multiple HLA-B supertype-matched donors are available. Future studies are needed to define the mechanisms by which supertype mismatching affects outcomes after alternative donor hematopoietic cell transplantation. PMID:27247320

  3. Algebra task & drill sheets

    CERN Document Server

    Reed, Nat

    2011-01-01

    For grades 3-5, our State Standards-based combined resource meets the algebraic concepts addressed by the NCTM standards and encourages the students to review the concepts in unique ways. The task sheets introduce the mathematical concepts to the students around a central problem taken from real-life experiences, while the drill sheets provide warm-up and timed practice questions for the students to strengthen their procedural proficiency skills. Included are opportunities for problem-solving, patterning, algebraic graphing, equations and determining averages. The combined task & drill sheets

  4. Algebra task & drill sheets

    CERN Document Server

    Reed, Nat

    2011-01-01

    For grades 6-8, our State Standards-based combined resource meets the algebraic concepts addressed by the NCTM standards and encourages the students to review the concepts in unique ways. The task sheets introduce the mathematical concepts to the students around a central problem taken from real-life experiences, while the drill sheets provide warm-up and timed practice questions for the students to strengthen their procedural proficiency skills. Included are opportunities for problem-solving, patterning, algebraic graphing, equations and determining averages. The combined task & drill sheets

  5. Bone mononuclear cells and pancreatic islets allograft in the treatment of diabetic rats%异体大鼠骨髓单个核细胞胰岛细胞移植治疗糖尿病

    Institute of Scientific and Technical Information of China (English)

    韩玮; 王云海; 王太成; 陈启龙

    2010-01-01

    Objective To study the curative effect of bone marrow mononuclear cells and pancreatic islets transplantation through the approach of the liver and tail vein. Methods The pancreatic islets and bone marrow mononuclear cells were isolated by discontinuous gradients centrifugation. Twenty-eight diabetic rats were randomly divided into groups A, B, C, and D. The rats in group A received 1000 pancreatic islets transplantation beneath the liver capsule, those in group B received transplantation of pancreatic islets and 1 × 107 bone marrow mononuclear cells beneath the liver capsule, those in group C received transplantation of 1000 pancreatic islets through the tail vein, and those in group D received transplantation of 1000 pancreatic islets and 1 × 107 bone marrow mononuclear cells through the tail vein. Plasma glucose level was determined at different time points. The effectiveness of combined different cells and transplantation approaches was compared. Results The blood glucose levels in groups A and B started to decrease in 3 days after transplantation. The blood glucose level in group A could be reduced to the normal level (7. 98 ±2. 28) mmol/L and maintain (3.71 ±0. 95) days, and that in group B could be reduced to (7. 72 ±1.75) mmol/L and maintain (4. 86 ± 1.06) days. The blood glucose level in groups C and D started to decrease in 4 days after transplantation. The blood glucose level in group C could be reduced to (7. 35 ±1.40) mmol/L and maintain (7. 85 ± 1.46) days, and that in group D to (7.00 ± 0. 83 ) mmol/L and maintain ( 14. 10 ± 1.21 ) days. There was statistically significant difference in blood glucose level among all groups ( P < 0. 05 ). Conclusion Transplantation of pancreatic islets combined with mononuclear cells through the tail vein in rats maintains the normal plasma glucose level for the longest duration. The plasma glucose level is ideal.%目的 观察异体骨髓单个核细胞和胰岛细胞通过肝脏和静脉途径移植后

  6. OX40 mRNA in peripheral blood as a biomarker of acute renal allograft rejection

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-liang; FU Ying-xin; ZHU Zhi-jun; WANG Hui; SHEN Zhong-yang

    2012-01-01

    Background Acute rejection remains an important cause of renal allograft dysfunction and the need for accurate diagnosis is essential to successfully treat transplant recipients.The purpose of this study was to determine the costimulatory molecules OX40 and OX40L messenger RNA (mRNA) levels in peripheral blood mononuclear cells (PBMCs) to predict acute renal transplant rejection.Methods The whole blood samples from 20 recipients with biopsy-confirmed acute rejection (rejection group),20 recipients with stable graft function and normal biopsy results (stable group) after kidney transplantation,and 20 healthy volunteers (control group) were collected.The mRNA levels of OX40 and OX40L were analyzed with TaqMan real-time reverse transcriptase polymerase chain reaction (RT-PCR).The association of OX40 and OX40L mRNA levels with disease severity was investigated.Results There was no significant difference of OX40,OX40L mRNA levels in PBMCs between the stable group and control group (P>0.05).The levels of OX40 and OX40L mRNA were significantly higher in the rejection group than in the control group (P<0.01 and P<0.05,respectively).Non-significantly higher OX40L mRNA and significantly higher OX40 mRNA in PBMCs were observed in subjects in the rejection group compared with the stable group (P >0.05 and P <0.01,respectively).Receiver operating characteristic (ROC) curve analysis demonstrated that OX40 mRNA levels could discriminate recipients who subsequently suffered acute allograft rejection (area under the curve,0.908).OX40 and OX40L mRNA levels did not significantly correlate with serum creatinine levels in the rejection group (P >0.05).Levels of OX40 mRNA after anti-rejection therapy were lower than those at the time of protocol biopsy in the rejection group (P<0.05).Conclusion Our data suggest that measurement of OX40 mRNA levels after transplant might offer a noninvasive means for recognizing recipients at risk of acute renal allograft rejection.

  7. Monitoring of human liver and kidney allograft tolerance: a tissue/histopathology perspective.

    Science.gov (United States)

    Demetris, Anthony J; Lunz, John G; Randhawa, Parmjeet; Wu, Tong; Nalesnik, Michael; Thomson, Angus W

    2009-01-01

    Several factors acting together have recently enabled clinicians to seriously consider whether chronic immunosuppression is needed in all solid organ allograft recipients. This has prompted a dozen or so centers throughout the world to prospectively wean immunosuppression from conventionally treated liver allograft recipients. The goal is to lessen the impact of chronic immunosuppression and empirically identify occasional recipients who show operational tolerance, defined as gross phenotype of tolerance in the presence of an immune response and/or immune deficit that has little or no significant clinical impact. Rare operationally tolerant kidney allograft recipients have also been identified, usually by single case reports, but only a couple of prospective weaning trials in conventionally treated kidney allograft recipients have been attempted and reported. Pre- and postweaning allograft biopsy monitoring of recipients adds a critical dimension to these trials, not only for patient safety but also for determining whether events in the allografts can contribute to a mechanistic understanding of allograft acceptance. The following is based on a literature review and personal experience regarding the practical and scientific aspects of biopsy monitoring of potential or actual operationally tolerant human liver and kidney allograft recipients where the goal, intended or attained, was complete withdrawal of immunosuppression.

  8. Acetabular allograft reconstruction in total hip arthroplasty. Part I: Current concepts in biomechanics.

    Science.gov (United States)

    Stiehl, J B

    1991-04-01

    Allograft reconstruction has become an essential tool for restoration of acetabular bone stock lost in failed total hip arthroplasty or resected in tumor reconstruction. This first segment of a two-part review will discuss the current status of allograft applications, together with pertinent biologic and biochemical aspects. Part II will address surgical considerations and recent clinical experience.

  9. Treatment of Steroid-Resistant Acute Renal Allograft Rejection With Alemtuzumab

    NARCIS (Netherlands)

    van den Hoogen, M. W. F.; Hesselink, D. A.; van Son, W. J.; Weimar, W.; Hilbrands, L. B.

    2013-01-01

    Steroid-resistant renal allograft rejections are commonly treated with rabbit antithymocyte globulin (RATG), but alemtuzumab could be an effective, safe and more convenient alternative. Adult patients with steroid-resistant renal allograft rejection treated with alemtuzumab (1530 mg s.c. on 2 subseq

  10. Treatment of steroid-resistant acute renal allograft rejection with alemtuzumab

    NARCIS (Netherlands)

    Hoogen, M.W. van den; Hesselink, D.A.; Son, W.J. van; Weimar, W.; Hilbrands, L.B.

    2013-01-01

    Steroid-resistant renal allograft rejections are commonly treated with rabbit antithymocyte globulin (RATG), but alemtuzumab could be an effective, safe and more convenient alternative. Adult patients with steroid-resistant renal allograft rejection treated with alemtuzumab (15-30 mg s.c. on 2 subse

  11. The renal arterial resistive index and stage of chronic kidney disease in patients with renal allograft

    DEFF Research Database (Denmark)

    Winther, Stine O; Thiesson, Helle C; Poulsen, Lene N;

    2012-01-01

    The study investigated the optimal threshold value of renal arterial resistive index as assessed by Doppler ultrasonography determining chronic kidney disease stage 4 or higher in patients with renal allograft.......The study investigated the optimal threshold value of renal arterial resistive index as assessed by Doppler ultrasonography determining chronic kidney disease stage 4 or higher in patients with renal allograft....

  12. HRSA Data Fact Sheets

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Health Resources and Services Administration (HRSA) Data Fact Sheets provide summary data about HRSA’s activities in each Congressional District, County, State,...

  13. Respirator Fact Sheet

    Science.gov (United States)

    ... have expiration dates that should be checked before purchase. Also, over time your mask can get old ... Respirator Fact Sheet [PDF - 706 KB] Follow NIOSH Facebook Flickr Pinterest Twitter YouTube NIOSH Homepage NIOSH A- ...

  14. Doppler Ultrasound in Chronic Renal Allograft Dysfunction : Can Acute Rejection be Predicted

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Kyung; Kim, Myeong Jin; Lee, Jong Tae; Yoo, Hyung Sik; Kim, Ki Whang; Park, Ki Ill; Chung, Hyun Joo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1995-12-15

    To investigate Doppler sonographic findings valuable for detecting acute rejection in transplanted kidney with chronic allograft dysfunction. Forty-three renal allografts who underwent renal Doppler sonography and renal biopsy due to chronic allograft dysfunction were included. According to histopathologic findings, patients were classified into 2 groups: chronic component only(group 1, n=30) and acute rejection with or without chronic component 2 groups were performed. No definite difference in radio of renal size, cortical echogenecity, corticomedullary differentiation was noted between group 1 and group 2.Resistive index was 0.61{+-}0.18 in group 1 and 0.64{+-}0.22 in group 2, which showed no statistically significant difference. Characteristic Doppler sonographic findings suggesting acute rejection in cases of chronic allograft dysfunction were not found inauther's study. Therefore, minimal invasive renal biopsy to determine histopathologic status of transplanted kidney is essential in evaluation of the chronic allograft dysfunction

  15. Proteinuria as a Noninvasive Marker for Renal Allograft Histology and Failure: An Observational Cohort Study.

    Science.gov (United States)

    Naesens, Maarten; Lerut, Evelyne; Emonds, Marie-Paule; Herelixka, Albert; Evenepoel, Pieter; Claes, Kathleen; Bammens, Bert; Sprangers, Ben; Meijers, Björn; Jochmans, Ina; Monbaliu, Diethard; Pirenne, Jacques; Kuypers, Dirk R J

    2016-01-01

    Proteinuria is routinely measured to assess renal allograft status, but the diagnostic and prognostic values of this measurement for renal transplant pathology and outcome remain unclear. We included 1518 renal allograft recipients in this prospective, observational cohort study. All renal allograft biopsy samples with concomitant data on 24-hour proteinuria were included in the analyses (n=2274). Patients were followed for ≥7 years post-transplantation. Compared with proteinuria 3.0 g/24 h, independent of GFR and allograft histology. The predictive performance of proteinuria for graft failure was lower at 3 months after transplant (area under the receiver-operating characteristic curve [AUC] 0.64, P3 months after transplant (AUC 0.73, P1.0 g/24 h. These data support current clinical guidelines to routinely measure proteinuria after transplant, but illustrate the need for more sensitive biomarkers of allograft injury and prognosis.

  16. Abdominal aortic aneurysm repair in patient with a renal allograft: a case report.

    Science.gov (United States)

    Kim, Hyung-Kee; Ryuk, Jong-Pil; Choi, Hyang Hee; Kwon, Sang-Hwy; Huh, Seung

    2009-02-01

    Renal transplant recipients requiring aortic reconstruction due to abdominal aortic aneurysm (AAA) pose a unique clinical problem. The concern during surgery is causing ischemic injury to the renal allograft. A variety of strategies for protection of the renal allograft during AAA intervention have been described including a temporary shunt, cold renal perfusion, extracorporeal bypass, general hypothermia, and endovascular stent-grafting. In addition, some investigators have reported no remarkable complications of the renal allograft without any specific measures. We treated a case of AAA in a patient with a renal allograft using a temporary aortofemoral shunt with good result. Since this technique is safe and effective, it should be considered in similar patients with AAA and previously placed renal allografts.

  17. Three-dimensional virtual bone bank system workflow for structural bone allograft selection: a technical report.

    Science.gov (United States)

    Ritacco, Lucas Eduardo; Farfalli, German Luis; Milano, Federico Edgardo; Ayerza, Miguel Angel; Muscolo, Domingo Luis; Aponte-Tinao, Luis

    2013-01-01

    Structural bone allograft has been used in bone defect reconstruction during the last fifty years with acceptable results. However, allograft selection methods were based on 2-dimensional templates using X-rays. Thanks to preoperative planning platforms, three-dimensional (3D) CT-derived bone models were used to define size and shape comparison between host and donor. The purpose of this study was to describe the workflow of this virtual technique in order to explain how to choose the best allograft using a virtual bone bank system. We measured all bones in a 3D virtual environment determining the best match. The use of a virtual bone bank system has allowed optimizing the allograft selection in a bone bank, providing more information to the surgeons before surgery. In conclusion, 3D preoperative planning in a virtual environment for allograft selection is an important and helpful tool in order to achieve a good match between host and donor.

  18. 2013 social balance sheet

    OpenAIRE

    Pierrette Heuse

    2014-01-01

    The transposition into national law of Directive 2013/34/EU on the annual financial statements of companies, expected by no later than July 2015, could alter the statistical obligations on small firms in connection with the filing of their annual accounts. In any case, the social balance sheet can no longer form an integral part of their accounts. Nevertheless, it contains original information whose usefulness is highlighted, on the basis of the social balance sheets for 2012, by examining th...

  19. Energy information sheets

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The National Energy Information Center (NEIC), as part of its mission, provides energy information and referral assistance to Federal, State, and local governments, the academic community, business and industrial organizations, and the public. The Energy Information Sheets was developed to provide general information on various aspects of fuel production, prices, consumption, and capability. Additional information on related subject matter can be found in other Energy Information Administration (EIA) publications as referenced at the end of each sheet.

  20. Quiescent interplay between inducible nitric oxide synthase and tumor necrosis factor-alpha: influence on transplant graft vasculopathy in renal allograft dysfunction.

    Science.gov (United States)

    Elahi, Maqsood M; Matata, Bashir M; Hakim, Nadey S

    2006-06-01

    A healthy endothelium is essential for vascular homeostasis, and preservation of endothelial cell function is critical for maintaining transplant allograft function. Damage to the microvascular endothelial cells is now regarded as a characteristic feature of acute vascular rejection, an important predictor of graft loss. It is also linked with transplant vasculopathy, often associated with chronic allograft nephropathy. Large bursts of nitric oxide in infiltrating monocytes/macrophages modulated by inducible nitric oxide synthase are considered pivotal in driving this mechanism. Indeed, it has been shown recently that increased circulating levels of tumor necrosis factor-alpha in the rejecting kidneys are largely responsible for triggering inducible nitric oxide synthase expression. This in turn suggests that several structural and functional features of graft rejection could be mediated by tumor necrosis factor-alpha. Despite the large body of evidence that supports immunologic involvement, knowledge concerning the cellular and biochemical mechanisms for nephritic cell dysfunction and death is incomplete. The role of tumor necrosis factor-alpha in mediating pathophysiological activity of inducible nitric oxide synthase during transplant vasculopathy remains contentious. Here, we discuss the effect of inducible nitric oxide synthase and tumor necrosis factor-alpha interaction on progressive damage to glomerular and vascular structures during renal allograft rejection. Selective inhibition of inducible nitrous oxide synthase and tumor necrosis factor-alpha as a potential therapy for ameliorating endothelial dysfunction and transplant graft vasculopathy is also discussed.

  1. Analysis of Sera of Recipients with Allograft Rejection Indicates That Keratin 1 Is the Target of Anti-Endothelial Antibodies

    Science.gov (United States)

    Guo, Xuli; Hu, Juan; Luo, Weiguang; Luo, Qizhi; Guo, Jing; Tian, Fang; Ming, Yingzi

    2017-01-01

    Anti-endothelial cell antibodies (AECAs) are usually directed against the surface antigens on the vascular endothelial cells. Clinical studies suggest a pathogenic role for nonhuman leukocyte antigen in antibody-mediated rejection; however, the antigens on the donor vascular endothelium that serve as the first-line targets for an immune response during allograft rejection have not been fully identified. Here, we used immunoprecipitation and mass spectrometry to identify antigens from the sera of kidney transplant recipients who were experiencing antibody-mediated rejection. Keratin 1 (KRT1) was identified as a novel antigenic target expressed on endothelial cells. To validate our finding, we produced recombinant proteins representing the three most common alleles of KRT1. The serum used for immunoprecipitation showed a strong reaction to KRT1 recombinants in western blot and ELISA. In the kidney transplant cohort, more AECA-positive recipients than AECA-negative recipients had KRT1 antibodies (32.2% versus 11.9%, p = 0.002). Sera from 255 renal recipients were tested by ELISA. Of the 77 recipients with deteriorating graft function (serum creatinine > 120 μmol/L), 23 had anti-KRT1 antibodies. KRT1-IgG positivity was, therefore, associated with a higher risk of kidney transplant rejection (29.9% (23/77) versus 16.9% (30/178), p = 0.0187). A better understanding of this antigenic target will improve long-term allograft survival.

  2. Methods for producing scaffold-free engineered cartilage sheets from auricular and articular chondrocyte cell sources and attachment to porous tantalum.

    Science.gov (United States)

    Whitney, G Adam; Mera, Hisashi; Weidenbecher, Mark; Awadallah, Amad; Mansour, Joseph M; Dennis, James E

    2012-08-01

    Scaffold-free cartilage engineering techniques may provide a simple alternative to traditional methods employing scaffolds. We previously reported auricular chondrocyte-derived constructs for use in an engineered trachea model; however, the construct generation methods were not reported in detail. In this study, methods for cartilage construct generation from auricular and articular cell sources are described in detail, and the resulting constructs are compared for use in a joint resurfacing model. Attachment of cartilage sheets to porous tantalum is also investigated as a potential vehicle for future attachment to subchondral bone. Large scaffold-free cartilage constructs were produced from culture-expanded chondrocytes from skeletally mature rabbits, and redifferentiated in a chemically-defined culture medium. Auricular constructs contained more glycosaminoglycan (39.6±12.7 vs. 9.7±1.9 μg/mg wet weight, mean and standard deviation) and collagen (2.7±0.45 vs. 1.1±0.2 μg/mg wet weight, mean and standard deviation) than articular constructs. Aggregate modulus was also higher for auricular constructs vs. articular constructs (0.23±0.07 vs. 0.12±0.03 MPa, mean and standard deviation). Attachment of constructs to porous tantalum was achieved by neocartilage ingrowth into tantalum pores. These results demonstrate that large scaffold-free neocartilage constructs can be produced from mature culture-expanded chondrocytes in a chemically-defined medium, and that these constructs can be attached to porous tantalum.

  3. Diagnosis and management of late hepatic allograft dysfunction

    Institute of Scientific and Technical Information of China (English)

    MEI Jian-min; YU Cong-hui

    2005-01-01

    Late hepatic allograft dysfunction (LHAD) is common after liver transplantation (LT) and can cause graft failure,retransplantation,or even death.A variety of etiologies including rejection,vascular complications,bile duct complications,recurrent diseases,infections,de novo diseases,neoplasms and drug toxicity can result in LHAD.The recurrent diseases have the potential to become the most serious problems facing LT in the future.It is difficult to differentiate late acute rejection from recurrent viral or autoimmune hepatitis.Accurate diagnosis of the cause of LHAD has therapeutic importance.

  4. Vascularized composite allograft-specific characteristics of immune responses.

    Science.gov (United States)

    Issa, Fadi

    2016-06-01

    Vascularized composite allograft (VCA) transplantation, or reconstructive transplantation, has revolutionized the treatment of complex tissue and functional defects. Despite arriving during an age in which the immunology of solid organ transplant rejection has been investigated in much detail, these transplants have offered new perspectives from which to explore the immunobiology of transplantation. VCAs have a number of unique molecular, cellular, and architectural features which alter the character and intensity of the rejection response. While much is yet to be clarified, an understanding of these distinct mechanisms affords new possibilities for the control of immune responses in an effort to improve outcomes after VCA transplantation.

  5. [Retinal regeneration with iPS cells ‒ Clinical trials for retinal degenerative disorders].

    Science.gov (United States)

    Sugita, Sunao

    2015-01-01

    Potential for re-programming cells has become widely accepted as a tool for obtaining transplantation materials. There has been great interest in cell-based therapies, including retinal transplants, because there is a reduced risk of immune rejection. Stem cells have the capacity for self-renewal plus the capacity to generate several differentiated cells. They are derived from many sources including human adult-derived induced pluripotent stem (iPS) cells and have found early application in the context of ocular disease. In results, our established iPS-retinal pigment epithelial (RPE) cells are high-quality RPE cells. iPS cells-derived RPE cells clearly showed polygonal morphology (mostly hexagonal) and contained melanin. Moreover, RPE cells derived from iPS cells had many characteristics of mature RPE cells in vivo, but no characteristics of pluripotent stem cells. Recently, we transplanted RPE cell sheets to treat a patient with wet age-related macular degeneration (September, 2014). In addition, we are now conducting experiments to determine whether allogeneic T cells can recognize iPS-RPE cells from HLA-A, B, DRB1 locus homozygote donors. iPS bank might be useful as allografts in retinal disorders, if the recipient T cells cannot respond to allogeneic RPE cells because of match to some of main HLA antigens.

  6. Living related conjunctival limbal allograft and amniotic membrane transplantation for limbal stem cell deficiency in chemically injured eyes%活体异体结膜缘和羊膜移植治疗化学性眼外伤造成的角膜缘干细胞缺失

    Institute of Scientific and Technical Information of China (English)

    Mehdi Hosseini Tehrani; Asoo Ali Mahmoudi; Hassan Hashemi; Syed Jafar Oskouee; Javad Amuzadeh; Mohammad Taher Rajabi; Masoomeh Taherzadeh; Hamideh Shenazandi

    2008-01-01

    eyes showed partial re-epithelialization, but failed to cover the entire corneal surface with epithelium. Best corrected visual acuity ranged from hand movement to counting finger at 1 meter before the surgery and after the surgery was light perception to 20/80. Five eyes had visual improvement without any additional procedure. Dry eye and persistent inflammation were known as main causes of failure.CONCLUSION: Living related conjunctival limbal allograft and amniotic membrane transplantation can be a good option in the management of limbal stem cell deficiency in selected cases in which tear production and control of ocular inflammation are adequate.

  7. Treatment strategies to minimize or prevent chronic allograft dysfunction in pediatric renal transplant recipients: an overview.

    Science.gov (United States)

    Höcker, Britta; Tönshoff, Burkhard

    2009-01-01

    Long-term allograft survival poses a major problem in pediatric renal transplantation, with allograft nephropathy being the principal cause of graft failure after the first post-transplant year. The mechanisms of nephron loss resulting in graft dysfunction are multiple, comprising both immunologic factors such as acute and chronic antibody- or T-cell-mediated rejection and non-immunologic components. The latter include peri-transplant injuries and renovascular lesions (renal artery stenosis, thrombosis) as well as cardiovascular risk factors such as arterial hypertension and hyperlipidemia. Another relevant issue leading to progressive nephron loss and declining kidney transplant function is acute and chronic nephrotoxicity induced by the calcineurin inhibitors (CNIs) ciclosporin (cyclosporine microemulsion) and tacrolimus. Furthermore, the presence of an abnormal lower urinary tract as well as bacterial (recurrent pyelonephritis) and viral (cytomegalovirus [CMV], polyomavirus [BK virus; BKV]) infections are crucial factors involved in the incidence of chronic allograft dysfunction and graft failure. Renovascular lesions and lower urinary tract obstruction are typical indicators for surgical intervention. The aim of treatment in pediatric patients with renal failure secondary to a dysfunctional lower urinary tract is to create a sterile, continent, and nonrefluxive reservoir. Surgical techniques such as bladder augmentation and the introduction of intermittent catheterization and anticholinergic therapy have significantly improved graft outcome. Arterial hypertension, another factor responsible for graft function deterioration in pediatric renal transplant recipients, is controlled preferably by the use of angiotensin converting enzyme (ACE) inhibitors or angiotensin II receptor antagonists, which are known to possess nephroprotective properties in addition to their potent antihypertensive effects. Although treatment of subclinical rejection with augmented

  8. Can Skin Allograft Occasionally Act as a Permanent Coverage in Deep Burns? A Pilot Study 

    Science.gov (United States)

    Rezaei, Ezzatollah; Beiraghi-Toosi, Arash; Ahmadabadi, Ali; Tavousi, Seyed Hassan; Alipour Tabrizi, Arash; Fotuhi, Kazem; Jabbari Nooghabi, Mehdi; Manafi, Amir; Ahmadi Moghadam, Shokoofeh

    2017-01-01

    BACKGROUND Skin allograft is the gold standard of wound coverage in patients with extensive burns; however, it is considered as a temporary wound coverage and rejection of the skin allograft is considered inevitable. In our study, skin allograft as a permanent coverage in deep burns is evaluated. METHODS Skin allograft survival was assessed in 38 patients from March 2009 to March 2014, retrospectively. Because of the lack of tissue specimen from the skin donors, patients with long skin allograft survival in whom the gender of donor and recipient of allograft was the same were excluded. Seven cases with skin allograft longevity and opposite gender in donor and recipient were finally enrolled. A polymerase chain reaction (PCR) test on the biopsy specimen from recipients and donors were undertaken. RESULTS PCR on the biopsy specimen from recipients confirmed those specimens belong to the donors. All patients received allograft from the opposite sex. Two (28.57%) patients received allograft from their first-degree blood relatives, and in one (14.29%) case, the allograft was harvested from an alive individual with no blood relation. The rest were harvested from multiorgan donors. In eight months of follow up, no clinical evidence of graft rejection was noted. CONCLUSION Long term persistence of skin allograft in patients is worthy of more attention. Further studies An increase in knowledge of factors influencing this longevity could realize the dream of burn surgeons to achieve a permanent coverage other than autograft for major burn patients.

  9. Association of high HLA-E expression during acute cellular rejection and numbers of HLA class I leader peptide mismatches with reduced renal allograft survival.

    Science.gov (United States)

    Guberina, Hana; Rebmann, Vera; Wagner, Bettina; da Silva Nardi, Fabiola; Dziallas, Phillip; Dolff, Sebastian; Bienholz, Anja; Wohlschlaeger, Jeremias; Bankfalvi, Agnes; Heinemann, Falko M; Witzke, Oliver; Zoet, Yvonne M; Claas, Frans H J; Horn, Peter A; Kribben, Andreas; Doxiadis, Ilias I N

    2017-03-01

    Non-classical Human Leukocyte Antigen (HLA)-E preferentially presents leader peptides derived from classical HLA-class I molecules. HLA-E can trigger opposed immune responses by interacting with inhibitory NKG2A or by activating NKG2C receptors on NK and T-cells. We studied the impact of HLA-E on renal allograft survival during acute cellular rejection. HLA-E expression was up-regulated in acute cellular rejection (ACR) biopsies (n=12) compared to biopsies from 13 renal allografts with no rejection-signs. HLA-E up-regulation was correlated with numbers of HLA-class I leader peptide mismatches (p=0.04). CD8+ and CD56+ infiltrating cells correlated with HLA-E expression (pE-mediated immune activation. Moreover, HLA-E expression correlated with deterioration in renal allograft function (pE along with high numbers of mismatched HLA-class I leader peptides might represent additional targets for immune-activating responses.

  10. "Glowing head" mice: a genetic tool enabling reliable preclinical image-based evaluation of cancers in immunocompetent allografts.

    Directory of Open Access Journals (Sweden)

    Chi-Ping Day

    Full Text Available Preclinical therapeutic assessment currently relies on the growth response of established human cell lines xenografted into immunocompromised mice, a strategy that is generally not predictive of clinical outcomes. Immunocompetent genetically engineered mouse (GEM-derived tumor allograft models offer highly tractable preclinical alternatives and facilitate analysis of clinically promising immunomodulatory agents. Imageable reporters are essential for accurately tracking tumor growth and response, particularly for metastases. Unfortunately, reporters such as luciferase and GFP are foreign antigens in immunocompetent mice, potentially hindering tumor growth and confounding therapeutic responses. Here we assessed the value of reporter-tolerized GEMs as allograft recipients by targeting minimal expression of a luciferase-GFP fusion reporter to the anterior pituitary gland (dubbed the "Glowing Head" or GH mouse. The luciferase-GFP reporter expressed in tumor cells induced adverse immune responses in wildtype mouse, but not in GH mouse, as transplantation hosts. The antigenicity of optical reporters resulted in a decrease in both the growth and metastatic potential of the labeled tumor in wildtype mice as compared to the GH mice. Moreover, reporter expression can also alter the tumor response to chemotherapy or targeted therapy in a context-dependent manner. Thus the GH mice and experimental approaches vetted herein provide concept validation and a strategy for effective, reproducible preclinical evaluation of growth and response kinetics for traceable tumors.

  11. Hearing Benefit in Allograft Tympanoplasty Using Tutoplast Processed Malleus

    Directory of Open Access Journals (Sweden)

    Anja Lieder

    2014-01-01

    Full Text Available Objectives. Tutoplast processed human cadaveric ossicular allografts are a safe alternative for ossicular reconstruction where there is insufficient material suitable for autograft ossiculoplasty. We present a series of 7 consecutive cases showing excellent air-bone gap closure following canal-wall-down mastoidectomy for cholesteatoma and reconstruction of the middle ear using Tutoplast processed malleus. Patients and Methods. Tympanoplasty with Tutoplast processed malleus was performed in seven patients to reconstruct the middle ear following canal-wall-down mastoidectomy in a tertiary ENT centre. Main Outcome Measures. Hearing improvement and recurrence-free period were assessed. Pre-and postoperative audiograms were performed. Results. The average pre operative hearing loss was 50 ± 13 dB, with an air-bone gap of 33 ± 7 dB. Post operative audiograms at 25 months demonstrated hearing thresholds of 29 ± 10 dB, with an air-bone gap of 14 ± 6 dB. No prosthesis extrusion was observed, which compares favourably to other commercially available prostheses. Conclusions. Tutoplast processed allografts restore conductive hearing loss in patients undergoing mastoidectomy and provide an excellent alternative when there is insufficient material suitable for autograft ossiculoplasty.

  12. A prospective study on knee proprioception after meniscal allograft transplantation.

    Science.gov (United States)

    Thijs, Y; Witvrouw, E; Evens, B; Coorevits, P; Almqvist, F; Verdonk, R

    2007-06-01

    The meniscus plays an important role in the proprioceptive ability of the knee joint. The aim of this prospective study was to assess the short-term influence of a meniscus replacement on the proprioception of the knee. Fourteen patients who had undergone a fresh meniscal allograft transplantation between May 2001 and June 2003 were tested pre-operatively and 6 months post-operatively. Disability regarding pain, stiffness and functionality of the affected knee during daily activities was measured by the Western Ontario and McMaster Universities Arthritis (WOMAC) scale. The knee joint position sense was assessed using the Biodex System 3 isokinetic dynamometer. The results of the WOMAC scale showed no significant differences concerning pain, stiffness or knee function between the pre- and post-operative condition of the knee. Assessment of the knee joint position sense at a reference point of 70 degrees of knee flexion revealed a significant improvement of the proprioception of the operated knee at 6 months after surgery compared with the pre-operative condition. The results of this study suggest that although no significant improvement of pain and functionality of the operated knee occurred at this short-term follow-up period, a meniscal allograft transplantation seems to have a significant positive effect on the joint position sense of the previously meniscectomised knee.

  13. De novo C3 glomerulonephritis in a renal allograft.

    Science.gov (United States)

    Nahm, Ji Hae; Song, Seung Hwan; Kim, Yu Seun; Cheong, Hae-Il; Lim, Beom Jin; Kim, Beom Seok; Jeong, Hyeon Joo

    2016-01-01

    C3 glomerulonephritis (C3GN) is a recently described, rare glomerular disease characterized by predominant or sole glomerular C3 deposits. Morphologic features of C3GN are similar to those of dense deposit disease (DDD); however, ribbon-like intramembranous electron-dense deposits are absent in the former. We report a case of de novo C3GN in a renal allograft with morphologic transformation to DDD. A 6-year-old boy presented with congenital left renal agenesis and right ureteropelvic junction obstruction. The patient underwent pyeloplasty but experienced recurrent urinary tract infections. At the age of 22 years, he received a renal allograft from a living related donor. C3GN was diagnosed after 1 year of transplantation; initial histology showed minimal mesangiopathy and this progressed to mesangial proliferation and membranoproliferative features over the next 7 years. Serum creatinine levels were stabilized with anti-rejection treatments for combating repeated episodes of acute rejection; however, glomerular and tubular band-like electron-dense deposits became evident.

  14. Renal allograft loss in the first post-operative month: causes and consequences.

    LENUS (Irish Health Repository)

    Phelan, Paul J

    2013-01-15

    Early transplant failure is a devastating outcome after kidney transplantation. We report the causes and consequences of deceased donor renal transplant failure in the first 30 d at our center between January 1990 and December 2009. Controls were adult deceased donor transplant patients in the same period with an allograft that functioned >30 d. The incidence of early graft failure in our series of 2381 consecutive deceased donor transplants was 4.6% (n = 109). The causes of failure were allograft thrombosis (n = 48; 44%), acute rejection (n = 19; 17.4%), death with a functioning allograft (n = 17; 15.6%), primary non-function (n = 14;12.8%), and other causes (n = 11; 10.1%). Mean time to allograft failure was 7.3 d. There has been a decreased incidence of all-cause early failure from 7% in 1990 to <1% in 2009. Patients who developed early failure had longer cold ischemia times when compared with patients with allografts lasting >30 d (p < 0.001). Early allograft failure was strongly associated with reduced patient survival (p < 0.001). In conclusion, early renal allograft failure is associated with a survival disadvantage, but has thankfully become less common in recent years.

  15. Utility of an allograft tendon for scoliosis correction via the costo-transverse foreman.

    Science.gov (United States)

    Sun, Dong; McCarthy, Michael; Dooley, Adam C; Ramakrishnaiah, Raghu H; Shelton, R Shane; McLaren, Sandra G; Skinner, Robert A; Suva, Larry J; McCarthy, Richard E

    2017-01-01

    Current convex tethering techniques for treatment of scoliosis have centered on anterior convex staples or polypropylene tethers. We hypothesized that an allograft tendon tether inserted via the costo-transverse foramen would correct an established spinal deformity. In the pilot study, six 8-week-old pigs underwent allograft tendon tethering via the costo-transverse foreman or sham to test the strength of the transplanted tendon to retard spine growth. After 4 months, spinal deformity in three planes was induced in all animals with allograft tendons. In the treatment study, the allograft tendon tether was used to treat established scoliosis in 11 8-week-old pigs (spinal deformity > 50°). Once the deformity was observed (4 months) animals were assigned to either no treatment group or allograft tendon tether group and progression assessed by monthly radiographs. At final follow-up, coronal Cobb angle and maximum vertebral axial rotation of the treatment group was significantly smaller than the non-treatment group, whereas sagittal kyphosis of the treatment group was significantly larger than the non-treatment group. In sum, a significant correction was achieved using a unilateral allograft tendon spinal tether, suggesting that an allograft tendon tethering approach may represent a novel fusion-less procedure to correct idiopathic scoliosis. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:183-192, 2017.

  16. Long-term outcomes of allograft reconstruction of the anterior cruciate ligament.

    Science.gov (United States)

    Lenehan, Eric A; Payne, W Barrett; Askam, Brad M; Grana, William A; Farrow, Lutul D

    2015-05-01

    Recent studies have found higher rates of failed reconstruction of the anterior cruciate ligament (ACL) with use of allograft when compared with autograft reconstruction. To evaluate the long-term outcomes of allograft ACL reconstruction, we retrospectively reviewed the cases of all patients who underwent allograft (n=99) or autograft (n=24) ACL reconstruction by 2 senior surgeons at a single institution over an 8-year period. Seventeen (17%) of the 99 allograft reconstructions required additional surgery. Reoperation and revision ACL reconstruction rates (30.8% and 20.5%, respectively) were much higher for patients 25 years of age or younger than for patients older than 25 years. In our cohort of NCAA (National Collegiate Athletic Association) Division I athletes, the revision ACL reconstruction rate was 62% for allograft ACL reconstruction and 0% for autograft reconstruction. Our study found that reoperation and revision rates for irradiated soft-tissue allograft ACL reconstruction were higher than generally quoted for autograft reconstruction. Given the extremely high graft failure rates in patients younger than 25 years, we recommend against routine use of irradiated soft-tissue allograft for ACL reconstruction in younger patients.

  17. Tc-99m DTPA scans in renal allograft rejection and cyclosporine nephrotoxicity

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    Gedroyc, W.; Taube, D.; Fogleman, I.; Neild, G.; Cameron, S.; Maisey, M.

    1986-11-01

    Renal allograft dysfunction arising from rejection or cyclosporine (CsA) nephrotoxicity can currently only be distinguished reliably by allograft biopsy. We have assessed Technetium (Tc)-99m diethylamine pentacetic acid (DTPA) scanning in 30 CsA-treated patients with allograft dysfunction. Scintigrams were performed during 20 biopsy-proved episodes of rejection and during 14 episodes of CsA nephrotoxicity. These results were compared with the scintigrams of 15 allografts showing stable function. Quantitative indices expressing allograft perfusion (flow index) and function (uptake index) derived from the DTPA scintigrams showed no significant differences between the groups of patients with rejection, CsA nephrotoxicity, or stable or improving function. Similarly, the flow and uptake indices of individual allografts obtained during periods of stable or improving function and then during episodes of dysfunction due to rejection or CsA nephrotoxicity did not significantly change. We conclude that Tc-99m DTPA scintigrams are of limited value in the management of allograft dysfunction in patients immunosuppressed with CsA.

  18. Renal Allograft Torsion: US and CT Imaging Findings of a Rare Posttransplant Complication

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    Rohit Dewan

    2016-01-01

    Full Text Available Vascular torsion is a rare renal transplant complication which requires prompt diagnosis and surgery to salvage allograft function. We report here a case of renal allograft torsion with interesting imaging findings on unenhanced CT and color Doppler ultrasound. A 60-year-old woman with a history of pancreas and kidney transplant presented to the emergency room with nausea, vomiting, abdominal pain, and minimal urine output. Unenhanced CT of the abdomen demonstrated an enlarged and malrotated renal allograft with moderate hydronephrosis. Color Doppler ultrasound demonstrated lack of vascularity within the allograft. The patient was taken urgently to the operating room where the renal allograft was found twisted 360 degrees around the vascular pedicle. After the allograft was detorsed, the color of the kidney returned and the Doppler signals for arterial flow improved. Intraoperative biopsy showed no evidence of infarct or acute cellular rejection. The detorsed kidney was surgically fixed in position in its upper and lower poles. Follow-up ultrasound 1 day later demonstrated normal blood flow to the renal allograft and the serum level of creatinine returned to normal.

  19. Renal Allograft Torsion: US and CT Imaging Findings of a Rare Posttransplant Complication.

    Science.gov (United States)

    Dewan, Rohit; Dasyam, Anil K; Tan, Henke; Furlan, Alessandro

    2016-01-01

    Vascular torsion is a rare renal transplant complication which requires prompt diagnosis and surgery to salvage allograft function. We report here a case of renal allograft torsion with interesting imaging findings on unenhanced CT and color Doppler ultrasound. A 60-year-old woman with a history of pancreas and kidney transplant presented to the emergency room with nausea, vomiting, abdominal pain, and minimal urine output. Unenhanced CT of the abdomen demonstrated an enlarged and malrotated renal allograft with moderate hydronephrosis. Color Doppler ultrasound demonstrated lack of vascularity within the allograft. The patient was taken urgently to the operating room where the renal allograft was found twisted 360 degrees around the vascular pedicle. After the allograft was detorsed, the color of the kidney returned and the Doppler signals for arterial flow improved. Intraoperative biopsy showed no evidence of infarct or acute cellular rejectio