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Sample records for cell sheet allografts

  1. 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.

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

    DEFF Research Database (Denmark)

    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...

  3. Association of CD14+ monocyte-derived progenitor cells with cardiac allograft vasculopathy

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    Salama, Mohamed; Andrukhova, Olena; Roedler, Susanne; Zuckermann, Andreas; Laufer, Guenther; Aharinejad, Seyedhossein

    2011-01-01

    Objective The pathogenesis of cardiac allograft vasculopathy after heart transplant remains controversial. Histologically, cardiac allograft vasculopathy is characterized by intimal hyperplasia of the coronary arteries induced by infiltrating cells. The origin of these infiltrating cells in cardiac allograft vasculopathy is unclear. Endothelial progenitor cells are reportedly involved in cardiac allograft vasculopathy; however, the role of CD14+ monocyte-derived progenitor cells in cardiac al...

  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. Regulatory Allospecific T Cell Clones Abrogate Chronic Allograft Rejection

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    Waaga-Gasser, Ana Maria; Grimm, Martin R.; Lutz, Jens; Lange, Volkmar; Lenhard, Susanne M.; Aviles, Beatriz; Kist-van Holthe, Joana E; Lebedeva, Tatiana; Samsonov, Dimitry; Meyer, Detlef; Hancock, Wayne W.; Heemann, Uwe; Gasser, Martin; Chandraker, Anil

    2009-01-01

    True alloantigen-specific tolerance is the ultimate goal of solid organ transplantation, eliminating the need for long-term immunosuppression. Recent evidence suggests that Th1-derived cytokines are associated with rejection and Th2-derived cytokines with long-term allograft survival, but the roles of these subsets in rejection and tolerance are incompletely understood. Here, we analyzed the functional and regulatory capacities of T cell clones derived from tolerant and rejecting rats (Wistar...

  6. Generation of suppressive blood cells for control of allograft rejection.

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    Kleist, Christian; Sandra-Petrescu, Flavius; Jiga, Lucian; Dittmar, Laura; Mohr, Elisabeth; Greil, Johann; Mier, Walter; Becker, Luis E; Lang, Peter; Opelz, Gerhard; Terness, Peter

    2015-05-01

    Our previous studies in rats showed that incubation of monocytic dendritic cells (DCs) with the chemotherapeutic drug mitomycin C (MMC) renders the cells immunosuppressive. Donor-derived MMC-DCs injected into the recipient prior to transplantation prolonged heart allograft survival. Although the generation of DCs is labour-intensive and time-consuming, peripheral blood mononuclear cells (PBMCs) can be easily harvested. In the present study, we analyse under which conditions DCs can be replaced by PBMCs and examine their mode of action. When injected into rats, MMC-incubated donor PBMCs (MICs) strongly prolonged heart allograft survival. Removal of monocytes from PBMCs completely abrogated their suppressive effect, indicating that monocytes are the active cell population. Suppression of rejection was donor-specific. The injected MICs migrated into peripheral lymphoid organs and led to an increased number of regulatory T-cells (Tregs) expressing cluster of differentiation (CD) markers CD4 and CD25 and forkhead box protein 3 (FoxP3). Tolerance could be transferred to syngeneic recipients with blood or spleen cells. Depletion of Tregs from tolerogenic cells abrogated their suppressive effect, arguing for mediation of immunosuppression by CD4⁺CD25⁺FoxP3⁺ Tregs. Donor-derived MICs also prolonged kidney allograft survival in pigs. MICs generated from donor monocytes were applied for the first time in humans in a patient suffering from therapy-resistant rejection of a haploidentical stem cell transplant. We describe, in the present paper, a simple method for in vitro generation of suppressor blood cells for potential use in clinical organ transplantation. Although the case report does not allow us to draw any conclusion about their therapeutic effectiveness, it shows that MICs can be easily generated and applied in humans.

  7. B cells mediate chronic allograft rejection independently of antibody production.

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    Zeng, Qiang; Ng, Yue-Harn; Singh, Tripti; Jiang, Ke; Sheriff, Khaleefathullah A; Ippolito, Renee; Zahalka, Salwa; Li, Qi; Randhawa, Parmjeet; Hoffman, Rosemary A; Ramaswami, Balathiripurasundari; Lund, Frances E; Chalasani, Geetha

    2014-03-01

    Chronic rejection is the primary cause of long-term failure of transplanted organs and is often viewed as an antibody-dependent process. Chronic rejection, however, is also observed in mice and humans with no detectable circulating alloantibodies, suggesting that antibody-independent pathways may also contribute to pathogenesis of transplant rejection. Here, we have provided direct evidence that chronic rejection of vascularized heart allografts occurs in the complete absence of antibodies, but requires the presence of B cells. Mice that were deficient for antibodies but not B cells experienced the same chronic allograft vasculopathy (CAV), which is a pathognomonic feature of chronic rejection, as WT mice; however, mice that were deficient for both B cells and antibodies were protected from CAV. B cells contributed to CAV by supporting splenic lymphoid architecture, T cell cytokine production, and infiltration of T cells into graft vessels. In chimeric mice, in which B cells were present but could not present antigen, both T cell responses and CAV were markedly reduced. These findings establish that chronic rejection can occur in the complete absence of antibodies and that B cells contribute to this process by supporting T cell responses through antigen presentation and maintenance of lymphoid architecture.

  8. B cells mediate chronic allograft rejection independently of antibody production.

    Science.gov (United States)

    Zeng, Qiang; Ng, Yue-Harn; Singh, Tripti; Jiang, Ke; Sheriff, Khaleefathullah A; Ippolito, Renee; Zahalka, Salwa; Li, Qi; Randhawa, Parmjeet; Hoffman, Rosemary A; Ramaswami, Balathiripurasundari; Lund, Frances E; Chalasani, Geetha

    2014-03-01

    Chronic rejection is the primary cause of long-term failure of transplanted organs and is often viewed as an antibody-dependent process. Chronic rejection, however, is also observed in mice and humans with no detectable circulating alloantibodies, suggesting that antibody-independent pathways may also contribute to pathogenesis of transplant rejection. Here, we have provided direct evidence that chronic rejection of vascularized heart allografts occurs in the complete absence of antibodies, but requires the presence of B cells. Mice that were deficient for antibodies but not B cells experienced the same chronic allograft vasculopathy (CAV), which is a pathognomonic feature of chronic rejection, as WT mice; however, mice that were deficient for both B cells and antibodies were protected from CAV. B cells contributed to CAV by supporting splenic lymphoid architecture, T cell cytokine production, and infiltration of T cells into graft vessels. In chimeric mice, in which B cells were present but could not present antigen, both T cell responses and CAV were markedly reduced. These findings establish that chronic rejection can occur in the complete absence of antibodies and that B cells contribute to this process by supporting T cell responses through antigen presentation and maintenance of lymphoid architecture. PMID:24509079

  9. 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.

  10. 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.

  11. Neutrophil mediated smooth muscle cell loss precedes allograft vasculopathy

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    Lee Timothy DG

    2010-06-01

    Full Text Available Abstract Background Cardiac allograft vasculopathy (AV is a pathological process of vascular remodeling leading to late graft loss following cardiac transplantation. While there is consensus that AV is alloimmune mediated, and evidence that the most important alloimmune target is medial smooth muscle cells (SMC, the role of the innate immune response in the initiation of this disease is still being elucidated. As ischemia reperfusion (IR injury plays a pivotal role in the initiation of AV, we hypothesize that IR enhances the early innate response to cardiac allografts. Methods Aortic transplants were performed between fully disparate mouse strains (C3H/HeJ and C57BL/6, in the presence of therapeutic levels of Cyclosporine A, as a model for cardiac AV. Neutrophils were depleted from some recipients using anti-PMN serum. Grafts were harvested at 1,2,3,5d and 1,2wk post-transplant. Ultrastructural integrity was examined by transmission electron microscopy. SMC and neutrophils were quantified from histological sections in a blinded manner. Results Grafts exposed to cold ischemia, but not transplanted, showed no medial SMC loss and normal ultrastructural integrity. In comparison, allografts harvested 1d post-transplant exhibited > 90% loss of SMC (p Conclusions These novel data show that there is extensive damage to medial SMC at 1d post-transplant. By depleting neutrophils from recipients it was demonstrated that a portion of the SMC loss was mediated by neutrophils. These results provide evidence that IR activation of early innate events contributes to the etiology of AV.

  12. Ectopic bone formation in bone marrow stem cell seeded calcium phosphate scaffolds as compared to autograft and (cell seeded allograft

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    J O Eniwumide

    2007-08-01

    Full Text Available Improvements to current therapeutic strategies are needed for the treatment of skeletal defects. Bone tissue engineering offers potential advantages to these strategies. In this study, ectopic bone formation in a range of scaffolds was assessed. Vital autograft and devitalised allograft served as controls and the experimental groups comprised autologous bone marrow derived stem cell seeded allograft, biphasic calcium phosphate (BCP and tricalcium phosphate (TCP, respectively. All implants were implanted in the back muscle of adult Dutch milk goats for 12 weeks. Micro-computed tomography (µCT analysis and histomorphometry was performed to evaluate and quantify ectopic bone formation. In good agreement, both µCT and histomorphometric analysis demonstrated a significant increase in bone formation by cell-seeded calcium phosphate scaffolds as compared to the autograft, allograft and cell-seeded allograft implants. An extensive resorption of the autograft, allograft and cell-seeded allograft implants was observed by histology and confirmed by histomorphometry. Cell-seeded TCP implants also showed distinct signs of degradation with histomorphometry and µCT, while the degradation of the cell-seeded BCP implants was negligible. These results indicate that cell-seeded calcium phosphate scaffolds are superior to autograft, allograft or cell-seeded allograft in terms of bone formation at ectopic implantation sites. In addition, the usefulness of µCT for the efficient and non-destructive analysis of mineralised bone and calcium phosphate scaffold was demonstrated.

  13. B-cell-mediated strategies to fight chronic allograft rejection

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    Ali H Dalloul

    2013-12-01

    Full Text Available Solid organs have been transplanted for decades. Since the improvement in graft selection and in medical and surgical procedures, the likelihood of graft function after one year is now close to 90%. Nonetheless even well-matched recipients continue to need medications for the rest of their lives hence adverse side effects and enhanced morbidity. Understanding Immune rejection mechanisms, is of increasing importance since the greater use of living-unrelated donors and genetically unmatched individuals. Chronic rejection is devoted to T-cells, however the role of B-cells in rejection has been appreciated recently by the observation that B-cell depletion improve graft survival. By contrast however, B-cells can be beneficial to the grafted tissue. This protective effect is secondary to either the secretion of protective antibodies or the induction of B-cells that restrain excessive inflammatory responses, chiefly by local provision of IL-10, or inhibit effector T-cells by direct cellular interactions. As a proof of concept B-cell-mediated infectious transplantation tolerance could be achieved in animal models, and evidence emerged that the presence of such B-cells in transplanted patients correlate with a favorable outcome. Among these populations, regulatory B-cells constitute a recently described population. These cells may develop as a feedback mechanism to prevent uncontrolled reactivity to antigens and inflammatory stimuli. The difficult task for the clinician, is to quantify the respective ratios and functions of tolerant vs effector B-cells within a transplanted organ, at a given time point in order to modulate B-cell-directed therapy. Several receptors at the B-cell membrane as well as signaling molecules, can now be targeted for this purpose. Understanding the temporal expansion of regulatory B-cells in grafted patients and the stimuli that activate them will help in the future to implement specific strategies aimed at fighting chronic

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

    Institute of Scientific and Technical Information of China (English)

    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.

  15. Donor-derived exosomes induce specific regulatory T cells to suppress immune inflammation in the allograft heart

    OpenAIRE

    Jiangping Song; Jie Huang; Xiao Chen; Xiao Teng; Zhizhao Song; Yong Xing; Mangyuan Wang; Kai Chen; Zheng Wang; Pingchang Yang; Shengshou Hu

    2016-01-01

    To inhibit the immune inflammation in the allografts can be beneficial to organ transplantation. This study aims to induce the donor antigen specific regulatory T cells (Treg cell) inhibit the immune inflammation in the allograft heart. In this study, peripheral exosomes were purified from the mouse serum. A heart transplantation mouse model was developed. The immune inflammation of the allograft heart was assessed by histology and flow cytometry. The results showed that the donor antigen-spe...

  16. 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.

  17. Arsenic trioxide inhibits accelerated allograft rejection mediated by alloreactive CD8(+) memory T cells and prolongs allograft survival time.

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    Li, Chun; Guan, Tianjun; Gao, Chang; Lin, Yingying; Yan, Guoliang; Zhu, Maoshu; Lv, Chongshan; Xia, Junjie; Qi, Zhongquan

    2015-09-01

    CD8(+) memory T (Tm) cells are a significant barrier to transplant tolerance induction in alloantigen-primed recipients, and are insensitive to existing clinical immunosuppressants. Here, we studied the inhibition of CD8(+) Tm cells by arsenic trioxide (As2O3) for the first time. Alloantigen-primed CD8(+) Tm cells were transferred to T cell immunodeficient nude mice. The mice were subjected to heart allotransplantation, and treated with As2O3. The transplant survival time was determined, and the inhibitory effects of As2O3 on CD8(+) Tm cell-mediated immune rejection were assessed through serological studies and inspection of the transplanted heart and lymphoid organs. We found that As2O3 treatment prolonged the mean survival time of the graft and reduced the number of CD8(+) Tm cells in the spleen and lymph nodes. The expression of the genes encoding interleukin (IL)-2, and IFN-γ was reduced, while expression of IL-10 and transforming growth factor-β was increased in the transplant. Our findings show that As2O3 treatment inhibits allograft rejection mediated by alloreactive CD8(+) Tm cells in the mouse heart transplantation model.

  18. 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.

  19. Cutting edge: membrane lymphotoxin regulates CD8(+) T cell-mediated intestinal allograft rejection.

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    Guo, Z; Wang, J; Meng, L; Wu, Q; Kim, O; Hart, J; He, G; Zhou, P; Thistlethwaite, J R; Alegre, M L; Fu, Y X; Newell, K A

    2001-11-01

    Blocking the CD28/B7 and/or CD154/CD40 costimulatory pathways promotes long-term allograft survival in many transplant models where CD4(+) T cells are necessary for rejection. When CD8(+) T cells are sufficient to mediate rejection, these approaches fail, resulting in costimulation blockade-resistant rejection. To address this problem we examined the role of lymphotoxin-related molecules in CD8(+) T cell-mediated rejection of murine intestinal allografts. Targeting membrane lymphotoxin by means of a fusion protein, mAb, or genetic mutation inhibited rejection of intestinal allografts by CD8(+) T cells. This effect was associated with decreased monokine induced by IFN-gamma (Mig) and secondary lymphoid chemokine (SLC) gene expression within allografts and spleens respectively. Blocking membrane lymphotoxin did not inhibit rejection mediated by CD4(+) T cells. Combining disruption of membrane lymphotoxin and treatment with CTLA4-Ig inhibited rejection in wild-type mice. These data demonstrate that membrane lymphotoxin is an important regulatory molecule for CD8(+) T cells mediating rejection and suggest a strategy to avoid costimulation blockade-resistant rejection. PMID:11673481

  20. 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.

  1. Induced regulatory T cells in allograft tolerance via transient mixed chimerism

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    Hotta, Kiyohiko; Aoyama, Akihiro; Oura, Tetsu; Yamada, Yohei; Tonsho, Makoto; Huh, Kyu Ha; Kawai, Kento; Schoenfeld, David; Allan, James S.; Madsen, Joren C.; Benichou, Gilles; Smith, Rex-Neal; Colvin, Robert B.; Sachs, David H.; Cosimi, A. Benedict; Kawai, Tatsuo

    2016-01-01

    Successful induction of allograft tolerance has been achieved in nonhuman primates (NHPs) and humans via induction of transient hematopoietic chimerism. Since allograft tolerance was achieved in these recipients without durable chimerism, peripheral mechanisms are postulated to play a major role. Here, we report our studies of T cell immunity in NHP recipients that achieved long-term tolerance versus those that rejected the allograft (AR). All kidney, heart, and lung transplant recipients underwent simultaneous or delayed donor bone marrow transplantation (DBMT) following conditioning with a nonmyeloablative regimen. After DBMT, mixed lymphocyte culture with CFSE consistently revealed donor-specific loss of CD8+ T cell responses in tolerant (TOL) recipients, while marked CD4+ T cell proliferation in response to donor antigens was found to persist. Interestingly, a significant proportion of the proliferated CD4+ cells were FOXP3+ in TOL recipients, but not in AR or naive NHPs. In TOL recipients, CD4+FOXP3+ cell proliferation against donor antigens was greater than that observed against third-party antigens. Finally, the expanded Tregs appeared to be induced Tregs (iTregs) that were converted from non-Tregs. These data provide support for the hypothesis that specific induction of iTregs by donor antigens is key to long-term allograft tolerance induced by transient mixed chimerism. PMID:27446989

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

    Institute of Scientific and Technical Information of China (English)

    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.

  3. Infused polymers for cell sheet release

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    Juthani, Nidhi; Howell, Caitlin; Ledoux, Haylea; Sotiri, Irini; Kelso, Susan; Kovalenko, Yevgen; Tajik, Amanda; Vu, Thy L.; Lin, Jennifer J.; Sutton, Amy; Aizenberg, Joanna

    2016-05-01

    Tissue engineering using whole, intact cell sheets has shown promise in many cell-based therapies. However, current systems for the growth and release of these sheets can be expensive to purchase or difficult to fabricate, hindering their widespread use. Here, we describe a new approach to cell sheet release surfaces based on silicone oil-infused polydimethylsiloxane. By coating the surfaces with a layer of fibronectin (FN), we were able to grow mesenchymal stem cells to densities comparable to those of tissue culture polystyrene controls (TCPS). Simple introduction of oil underneath an edge of the sheet caused it to separate from the substrate. Characterization of sheets post-transfer showed that they retain their FN layer and morphology, remain highly viable, and are able to grow and proliferate normally after transfer. We expect that this method of cell sheet growth and detachment may be useful for low-cost, flexible, and customizable production of cellular layers for tissue engineering.

  4. 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.

  5. 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.

  6. 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.

  7. Urinary Cell mRNA Profiles Predictive of Human Kidney Allograft Status

    OpenAIRE

    Lee, John R.; Muthukumar, Thangamani; Dadhania, Darshana; Ding, Ruchuang; Sharma, Vijay K; Joseph E Schwartz; Suthanthiran, Manikkam

    2014-01-01

    Kidney allograft status is currently characterized using the invasive percutaneous needle core biopsy procedure. The procedure has become safer over the years, but challenges and complications still exist including sampling error, inter-observer variability, bleeding, arteriovenous fistula, graft loss, and even death. Because the most common type of acute rejection is distinguished by inflammatory cells exiting the intravascular compartment and gaining access to the renal tubular space, we re...

  8. Urinary cell mRNA profiles predictive of human kidney allograft status.

    Science.gov (United States)

    Lee, John R; Muthukumar, Thangamani; Dadhania, Darshana; Ding, Ruchuang; Sharma, Vijay K; Schwartz, Joseph E; Suthanthiran, Manikkam

    2014-03-01

    Kidney allograft status is currently characterized using the invasive percutaneous needle core biopsy procedure. The procedure has become safer over the years, but challenges and complications still exist including sampling error, interobserver variability, bleeding, arteriovenous fistula, graft loss, and even death. Because the most common type of acute rejection is distinguished by inflammatory cells exiting the intravascular compartment and gaining access to the renal tubular space, we reasoned that a kidney allograft may function as an in vivo flow cytometer and sort cells involved in rejection into urine. To test this idea, we developed quantitative polymerase chain reaction (PCR) assays for absolute quantification of mRNA and pre-amplification protocols to overcome the low RNA yield from urine. Here, we review our single center urinary cell mRNA profiling studies that led to the multicenter Clinical Trials in Organ Transplantation (CTOT-04) study and the discovery and validation of a 3-gene signature of 18S rRNA-normalized measures of CD3ε mRNA and IP-10 mRNA and 18S rRNA that is diagnostic and predictive of acute cellular rejection in the kidney allograft. We also review our development of a 4-gene signature of mRNAs for vimentin, NKCC2, E-cadherin, and 18S rRNA diagnostic of interstitial fibrosis/tubular atrophy (IF/TA). PMID:24517436

  9. Participation of functionally active plasma cells in acute rejection and response to therapy in renal allografts.

    Science.gov (United States)

    Bhat, Zeenat Yousuf; Bostwick, David G; Hossain, Deloar; Zeng, Xu

    2014-07-01

    Acute rejection (AR) includes T-cell-mediated and antibody-mediated rejection. The inflammatory infiltrate comprised not only T cells but also varying amounts of B cells (CD20(+)) and plasma cells (CD138(+)). The latter are associated with poor clinical outcomes, but their functional status is not clear. The phosphorylation of the S6 ribosomal protein (p-S6RP) is present in cells that are metabolically active, thus identifying functionally active antibody-secreting plasma cells. This study was designed to evaluate the clinical significance of functionally active p-S6RP plasma cells in AR in renal allografts. Renal allografts with biopsy evidence of AR during 2006-2009 were included. Immunohistochemistry staining for CD20, CD138, and p-S6RP was performed on paraffin-embedded slides and scaled as 0-6. The response to antirejection treatment was assessed by the serum creatinine ratio (CrR) at rejection episode (time 0) and following treatment (4 and 12 weeks). Patients with lower scores (0-2) were compared with a higher scored group (3-6). The T-test was conducted using statistical significance of p<0.05. A total of 28 patients (40.7 ± 14.3 year; M:F=15:13) were diagnosed with acute T-cell-mediated rejection (I and II). The p-S6RP staining in the high-score group had a significantly higher CrR (p<0.05) than the low-score group at the time of biopsy, 4 and 12 weeks following treatment. There was no significant difference in the CrR between groups for CD20 or CD138 staining. Functional antibody-secreting p-S6RP plasma cells are actively participating in AR and associated with poor response to treatment in renal allografts. PMID:24684655

  10. 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.

  11. 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.

  12. Cell therapy to induce allograft tolerance: Time to switch to plan B?

    Directory of Open Access Journals (Sweden)

    Antoine eSicard

    2015-04-01

    Full Text Available Organ transplantation is widely acknowledged as the best option for end stage failure of vital organs. Long-term graft survival is however limited by graft rejection, a destructive process resulting from the response of recipient’s immune system against donor-specific alloantigens. Prevention of rejection currently relies exclusively on immunosuppressive drugs that lack antigen specificity and therefore increase the risk for infections and cancers. Induction of donor-specific tolerance would provide indefinite graft survival without morbidity and therefore represents the Grail of transplant immunologists.Progresses in the comprehension of immunoregulatory mechanisms over the last decades have paved the way for cell therapies to induce allograft tolerance. The first part of the present article reviews the promising results obtained in experimental models with adoptive transfer of ex vivo-expanded regulatory CD4+ T cells (CD4+ Tregs and discuss which source and specificity should be preferred for transferred CD4+ Tregs. Interestingly, B cells have recently emerged as potent regulatory cells, able to establish a privileged crosstalk with CD4+ T cells. The second part of the present article reviews the evidences demonstrating the crucial role of regulatory B cells in transplantation tolerance. We propose the possibility to harness B cell regulatory functions to improve cell-based therapies aiming at inducing allograft tolerance.

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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

  18. Interruption of dendritic cell-mediated TIM-4 signaling induces regulatory T cells and promotes skin allograft survival.

    Science.gov (United States)

    Yeung, Melissa Y; McGrath, Martina M; Nakayama, Masafumi; Shimizu, Tetsunosuke; Boenisch, Olaf; Magee, Ciara N; Abdoli, Rozita; Akiba, Hisaya; Ueno, Takuya; Turka, Laurence A; Najafian, Nader

    2013-10-15

    Dendritic cells (DCs) are the central architects of the immune response, inducing inflammatory or tolerogenic immunity, dependent on their activation status. As such, DCs are highly attractive therapeutic targets and may hold the potential to control detrimental immune responses. TIM-4, expressed on APCs, has complex functions in vivo, acting both as a costimulatory molecule and a phosphatidylserine receptor. The effect of TIM-4 costimulation on T cell activation remains unclear. In this study, we demonstrate that Ab blockade of DC-expressed TIM-4 leads to increased induction of induced regulatory T cells (iTregs) from naive CD4(+) T cells, both in vitro and in vivo. iTreg induction occurs through suppression of IL-4/STAT6/Gata3-induced Th2 differentiation. In addition, blockade of TIM-4 on previously activated DCs still leads to increased iTreg induction. iTregs induced under TIM-4 blockade have equivalent potency to control and, upon adoptive transfer, significantly prolong skin allograft survival in vivo. In RAG(-/-) recipients of skin allografts adoptively transferred with CD4(+) T cells, we show that TIM-4 blockade in vivo is associated with a 3-fold prolongation in allograft survival. Furthermore, in this mouse model of skin transplantation, increased induction of allospecific iTregs and a reduction in T effector responses were observed, with decreased Th1 and Th2 responses. This enhanced allograft survival and protolerogenic skewing of the alloresponse is critically dependent on conversion of naive CD4(+) to Tregs in vivo. Collectively, these studies identify blockade of DC-expressed TIM-4 as a novel strategy that holds the capacity to induce regulatory immunity in vivo.

  19. Intracranial Orthotopic Allografting of Medulloblastoma Cells in Immunocompromised Mice

    OpenAIRE

    Huang, Xi; Sarangi, Anuraag; Ketova, Tatiana; LItingtung, Ying; Cooper, Michael K.; Chiang, Chin

    2010-01-01

    Medulloblastoma is the most common pediatric tumor of the nervous system. A large body of animal studies has focused on cerebellar granule neuron precursors (CGNPs) as the cell-of-origin for medulloblastoma1-4. However, the diverse clinical presentations of medulloblastoma subtypes in human patients (nodular, desmoplastic, classical and large cell/anaplastic), and the fact that medulloblastoma is found in a subset of human patients with no ectopic expression of CGNP marker5, suggest that the ...

  20. 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.

  1. 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.

  2. Complement component 3 deficiency prolongs MHC-II disparate skin allograft survival by increasing the CD4+ CD25+ regulatory T cells population

    Science.gov (United States)

    Zheng, Quan-you; Liang, Shen-ju; Li, Gui-qing; Lv, Yan-bo; Li, You; Tang, Ming; Zhang, Kun; Xu, Gui-lian; Zhang, Ke-qin

    2016-01-01

    Recent reports suggest that complement system contributes to allograft rejection. However, its underlying mechanism is poorly understood. Herein, we investigate the role of complement component 3 (C3) in a single MHC-II molecule mismatched murine model of allograft rejection using C3 deficient mice (C3−/−) as skin graft donors or recipients. Compared with C3+/+ B6 allografts, C3−/− B6 grafts dramatically prolonged survival in MHC-II molecule mismatched H-2bm12 B6 recipients, indicating that C3 plays a critical role in allograft rejection. Compared with C3+/+ allografts, both Th17 cell infiltration and Th1/Th17 associated cytokine mRNA levels were clearly reduced in C3−/− allografts. Moreover, C3−/− allografts caused attenuated Th1/Th17 responses, but increased CD4+CD25+Foxp3+ regulatory T (Treg) cell expression markedly in local intragraft and H-2bm12 recipients. Depletion of Treg cells by anti-CD25 monoclonal antibody (mAb) negated the survival advantages conferred by C3 deficiency. Our results indicate for the first time that C3 deficiency can prolong MHC-II molecule mismatched skin allograft survival, which is further confirmed to be associated with increased CD4+ CD25+ Treg cell population expansion and attenuated Th1/Th17 response. PMID:27641978

  3. Complement component 3 deficiency prolongs MHC-II disparate skin allograft survival by increasing the CD4(+) CD25(+) regulatory T cells population.

    Science.gov (United States)

    Zheng, Quan-You; Liang, Shen-Ju; Li, Gui-Qing; Lv, Yan-Bo; Li, You; Tang, Ming; Zhang, Kun; Xu, Gui-Lian; Zhang, Ke-Qin

    2016-01-01

    Recent reports suggest that complement system contributes to allograft rejection. However, its underlying mechanism is poorly understood. Herein, we investigate the role of complement component 3 (C3) in a single MHC-II molecule mismatched murine model of allograft rejection using C3 deficient mice (C3(-/-)) as skin graft donors or recipients. Compared with C3(+/+) B6 allografts, C3(-/-) B6 grafts dramatically prolonged survival in MHC-II molecule mismatched H-2(bm12) B6 recipients, indicating that C3 plays a critical role in allograft rejection. Compared with C3(+/+) allografts, both Th17 cell infiltration and Th1/Th17 associated cytokine mRNA levels were clearly reduced in C3(-/-) allografts. Moreover, C3(-/-) allografts caused attenuated Th1/Th17 responses, but increased CD4(+)CD25(+)Foxp3(+) regulatory T (Treg) cell expression markedly in local intragraft and H-2(bm12) recipients. Depletion of Treg cells by anti-CD25 monoclonal antibody (mAb) negated the survival advantages conferred by C3 deficiency. Our results indicate for the first time that C3 deficiency can prolong MHC-II molecule mismatched skin allograft survival, which is further confirmed to be associated with increased CD4(+) CD25(+) Treg cell population expansion and attenuated Th1/Th17 response. PMID:27641978

  4. Autologous Bone Marrow Stem Cells combined with Allograft Cancellous Bone in Treatment of Nonunion

    Directory of Open Access Journals (Sweden)

    Le Thua Trung Hau

    2015-12-01

    Full Text Available Autologous cancellous bone graft is currently used as a gold standard method for treatment of bone nonunion. However, there is a limit to the amount of autologous cancellous bone that can be harvested and the donor site morbidity presents a major disadvantage to autologous bone grafting. Embedding viable cells within biological scaffolds appears to be extremely promising. The purpose of this study was to assess the outcome of autologous bone marrow stem cells combined with a cancellous bone allograft as compared to an autologous bone graft in the treatment of bone nonunion. Bone marrow aspiration concentrate (BMAC was previously produced from bone marrow aspirate via a density gradient centrifugation. Autologous cancellous bone was harvested in 9 patients and applied to the nonunion site. In 18 patients of the clinical trial group after the debridement, the bone gaps were filled with a composite of BMAC and allograft cancellous bone chips (BMAC-ACB. Bone consolidation was obtained in 88.9 %, and the mean interval between the cell transplantation and union was 4.6 +/- 1.5 months in the autograft group. Bone union rate was 94.4 % in group of composite BMAC-ACB implantation. The time to union in BMAC-ACB grafting group was 3.3 +/- 0.90 months, and led to faster healing when compared to the autograft. A mean concentration of autologous progenitor cells was found to be 2.43 +/- 1.03 (x106 CD34+ cells/ml, and a mean viability of CD34+ cells was 97.97 +/- 1.47 (%. This study shows that the implantation of BMAC has presented the efficacy for treatment of nonunion and may contribute an available alternative to autologous cancellous bone graft. But large clinical application of BM-MSCs requires a more appropriate and profound scientific investigations. [Biomed Res Ther 2015; 2(12.000: 409-417

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

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    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.

  6. 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.

  7. 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.

  8. Dendritic Cells Transduced with SOCS1 Gene Exhibit Regulatory DC Properties and Prolong Allograft Survival

    Institute of Scientific and Technical Information of China (English)

    Hong Fu; Shaohua Song; Fang Liu; Zhijia Ni; Yi Tang; Xiaoyun Shen; Liang Xiao; Guoshan Ding; Quanxing Wang

    2009-01-01

    SOCS1 is a key regulator of cytokine signaling and is important for maintaining balance in the immune system. It is thought to participate in negative feedback loops in cytokine signaling and may be an important signal for the regulation of dendritic cell (DC) maturation. However, it remains unclear whether DCs transduced with SOCS1 exhibit characteristics of regulatory DCs and induce allogeneic T-cell hyporesponsiveness. In this study, we constructed adenoviral vector coding SOCS1 (Ad-SOCS1) that can efficiently increase SOCS1 gene expression in bone marrow-derived dendritic cells. DCs transduced with Ad-SOCS1 (DC-SOCS1) expressed low levels of costimulatory and MHC molecules, were resistant to maturation and activation stimulation, induced allogeneic T-cell hyporesponsiveness, and promoted the generation of regulatory-like T cells in vitro. DC-SOCS1 pretreatment significantly prolonged the survival of allografts and led to a substantial increase in the generation of regulatory T cells. Our data suggest that SOCS1 inhibits DC maturation and induces regulatory DC generation, therefore possessing therapeutic potential to prevent rejection in organ transplantation. Cellular & Molecular Immunology.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Withania somnifera Suppresses Tumor Growth of Intracranial Allograft of Glioma Cells.

    Science.gov (United States)

    Kataria, Hardeep; Kumar, Sushil; Chaudhary, Harshita; Kaur, Gurcharan

    2016-08-01

    Gliomas are the most frequent type of primary brain tumor in adults. Their highly proliferative nature, complex cellular composition, and ability to escape therapies have confronted investigators for years, hindering the advancement toward an effective treatment. Agents that are safe and can be administered as dietary supplements have always remained priority to be most feasible for cancer therapy. Withania somnifera (ashwagandha) is an essential ingredient of Ayurvedic preparations and is known to eliminate cancer cells derived from a variety of peripheral tissues. Although our previous studies have addressed the in vitro anti-proliferative and differentiation-inducing properties of ashwagandha on neuronal cell lines, in vivo studies validating the same are lacking. While exploring the mechanism of its action in vitro, we observed that the ashwagandha water extract (ASH-WEX) induced the G2/M phase blockade and caused the activation of multiple pro-apoptotic pathways, leading to suppression of cyclin D1, bcl-xl, and p-Akt, and reduced the expression of polysialylated form of neural cell adhesion molecule (PSA-NCAM) as well as the activity of matrix metalloproteinases. ASH-WEX reduced the intracranial tumor volumes in vivo and suppressed the tumor-promoting proteins p-nuclear factor kappa B (NF-κB), p-Akt, vascular endothelial growth factor (VEGF), heat shock protein 70 (HSP70), PSA-NCAM, and cyclin D1 in the rat model of orthotopic glioma allograft. Reduction in glial fibrillary acidic protein (GFAP) and upregulation of mortalin and neural cell adhesion molecule (NCAM) expression specifically in tumor-bearing tissue further indicated the anti-glioma efficacy of ASH-WEX in vivo. Combining this enhanced understanding of the molecular mechanisms of ASH-WEX in glioma with in vivo model system offers new opportunities to develop therapeutic strategy for safe, specific, and effective formulations for treating brain tumors. PMID:26208698

  14. 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.

  15. 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.

  16. 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.

  17. Regulatory T Cell Infusion Can Enhance Memory T Cell and Alloantibody Responses in Lymphodepleted Nonhuman Primate Heart Allograft Recipients.

    Science.gov (United States)

    Ezzelarab, M B; Zhang, H; Guo, H; Lu, L; Zahorchak, A F; Wiseman, R W; Nalesnik, M A; Bhama, J K; Cooper, D K C; Thomson, A W

    2016-07-01

    The ability of regulatory T cells (Treg) to prolong allograft survival and promote transplant tolerance in lymphodepleted rodents is well established. Few studies, however, have addressed the therapeutic potential of adoptively transferred, CD4(+) CD25(+) CD127(-) Foxp3(+) (Treg) in clinically relevant large animal models. We infused ex vivo-expanded, functionally stable, nonselected Treg (up to a maximum cumulative dose of 1.87 billion cells) into antithymocyte globulin-lymphodepleted, MHC-mismatched cynomolgus monkey heart graft recipients before homeostatic recovery of effector T cells. The monkeys also received tacrolimus, anti-interleukin-6 receptor monoclonal antibodies and tapered rapamycin maintenance therapy. Treg administration in single or multiple doses during the early postsurgical period (up to 1 month posttransplantation), when host T cells were profoundly depleted, resulted in inferior graft function compared with controls. This was accompanied by increased incidences of effector memory T cells, enhanced interferon-γ production by host CD8(+) T cells, elevated levels of proinflammatory cytokines, and antidonor alloantibodies. The findings caution against infusion of Treg during the early posttransplantation period after lymphodepletion. Despite marked but transient increases in Treg relative to endogenous effector T cells and use of reputed "Treg-friendly" agents, the host environment/immune effector mechanisms instigated under these conditions can perturb rather than favor the potential therapeutic efficacy of adoptively transferred Treg. PMID:26700196

  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. 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

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. T Helper Cells Fate Mapping by Co-stimulatory Molecules and its Functions in Allograft Rejection and Tolerance.

    Science.gov (United States)

    Abdoli, R; Najafian, N

    2014-01-01

    T cell differentiation is dictated by a combination of T cell receptor (TCR) interaction with an antigen-bound major histocompatibility complex (MHC), and co-stimulatory molecules signal. The co-stimulatory signal can be positive or negative, and amplifying or diminishing the initial signal. However, the secondary co-stimulatory signal is not obligatory and its necessity is dictated, in part, by the stage of T cell development. In the field of transplantation, directing the T cell differentiation process can lead to therapeutic possibilities that promote allograft tolerance, and hinder unfavorable alloimmune responses. Therefore, understanding the details of T cell differentiation process, including the influence of co-stimulatory signals, is of paramount importance. It is important to note there is functional overlap between co-stimulatory molecules. It has been observed that some co-stimulatory signals have different effects on different T cell subsets. Hence, blockade of a co-stimulatory signal pathway, as part of a therapeutic regimen in transplantation, may have far reaching effects beyond the initial therapeutic intent and inhibit co-stimulatory signals necessary for desirable regulatory responses. In this review, co-stimulatory molecules involved in the differentiation of naïve T cells into T helper 1 (Th1), T helper 2 (Th2), T helper 17 (Th17), inducible regulatory T cells (iTregs), and T helper 9 (Th9) cells and their overlap are discussed.

  8. 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.

  9. 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.

  10. Treatment of humeral shaft aseptic nonunions in elderly patients with opposite structural allograft, BMP-7, and mesenchymal stem cells.

    Science.gov (United States)

    Murena, Luigi; Canton, Gianluca; Vulcano, Ettore; Surace, Michele Francesco; Cherubino, Paolo

    2014-02-01

    Humeral shaft aseptic nonunions occur in 2% to 10% of patients managed conservatively and 10% to 15% of patients treated surgically. The complex muscular and neurovascular anatomy of the upper limb makes the surgical approach to the fracture site demanding and risky, especially when previous surgeries have been attempted. The clinical consequence of atrophic humeral shaft nonunions is a severe functional limitation that may significantly affect activities of daily living, especially in the elderly. The surgical treatment of humeral shaft nonunions is challenging for orthopedic surgeons. Patients with atrophic nonunions require both a stable fixation and enhancement of the biologic response because of the weak biologic reaction observed at the fracture site. The gold standard of treatment in elderly patients has not been described. Nonetheless, older age and comorbidities are associated with potentially malignant nonunions. This study reports the authors' experience using opposite cortical allograft combined with bone morphogenetic protein 7 and mesenchymal stem cells to treat humeral shaft atrophic nonunions in 2 elderly patients. The nonunion site healed at 4 months (patient 1) and 8 months (patient 2) postoperatively, with full return to activities of daily living and no pain. Neither patient reported complications of the radial nerve, which is at high risk of injury during this type of surgery. The only reported complication (patient 2) was an intraoperative longitudinal partial distal humeral fracture, probably caused by compression screw overtightening. The use of a locking plate and opposite cortical allograft, combined with BMP-7 and mesenchymal stem cells, represents a safe and effective treatment for malignant nonunions in older patients. PMID:24679209

  11. 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.

  12. Ectopic bone formation in bone marrow stem cell seeded calcium phosphate scaffolds as compared to autograft and (cell seeded) allograft

    NARCIS (Netherlands)

    Eniwumide, J.O.; Yuan, H.; Cartmell, S.H.; Meijer, G.J.; Bruijn, J.D. de

    2007-01-01

    Improvements to current therapeutic strategies are needed for the treatment of skeletal defects. Bone tissue engineering offers potential advantages to these strategies. In this study, ectopic bone formation in a range of scaffolds was assessed. Vital autograft and devitalised allograft served as co

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

    Science.gov (United States)

    2012-01-01

    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 compared to

  14. 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

    Directory of Open Access Journals (Sweden)

    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.

  15. Effects of Adoptive Transfer of Tolerogenic Dendritic Cells on Allograft Survival in Organ Transplantation Models: An Overview of Systematic Reviews

    Science.gov (United States)

    Shan, Juan; Guo, Yingjia; Li, Shengfu; Long, Dan

    2016-01-01

    Objective. To dissect the efficacy of Tol-DC therapy with or without IS in multiple animal models of transplantation. Methods and Results. PubMed, Medline, Embase, and the Cochrane Library were searched for reviews published up to April 2015. Six systematic reviews and a total of 61 articles were finally included. Data were grouped by organ transplantation models and applied to meta-analysis. Our meta-analysis shows that Tol-DC therapy successfully prolonged allograft survival to varying extents in all except the islet transplantation models and with IS drugs further prolonged the survival of heart, skin, and islet allografts in mice, but not of heart allografts in rats. Compared with IS drugs alone, Tol-DC therapy with IS extended islet allograft survival in rats but failed to influence the survival of skin, small intestine, and heart allografts in rats or of heart and skin allografts in mice. Conclusion. Tol-DC therapy significantly prolonged multiple allograft survival and further prolonged survival with IS. However, standardized protocols for modification of Tol-DC should be established before its application in clinic.

  16. Sheet plastic filters for solar cells

    Science.gov (United States)

    Wizenick, R. J.

    1972-01-01

    Poly(vinylidene fluoride) (PVF) film protects solar cells on Mars surface from radiation and prevents degradation of solar cell surfaces by Martian dust storms. PVF films may replace glass or quartz windows on solar cell arrays used to generate power on earth.

  17. 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.

  18. 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.

  19. Adoptive infusion of tolerogenic dendritic cells prolongs the survival of pancreatic islet allografts: a systematic review of 13 mouse and rat studies.

    Directory of Open Access Journals (Sweden)

    Guixiang Sun

    Full Text Available OBJECTIVE: The first Phase I study of autologous tolerogenic dendritic cells (Tol-DCs in Type 1 diabetes (T1D patients was recently completed. Pancreatic islet transplantation is an effective therapy for T1D, and infusion of Tol-DCs can control diabetes development while promoting graft survival. In this study, we aim to systematically review islet allograft survival following infusion of Tol-DCs induced by different methods, to better understand the mechanisms that mediate this process. METHODS: We searched PubMed and Embase (from inception to February 29(th, 2012 for relevant publications. Data were extracted and quality was assessed by two independent reviewers. We semiquantitatively analyzed the effects of Tol-DCs on islet allograft survival using mixed leukocyte reaction, Th1/Th2 differentiation, Treg induction, and cytotoxic T lymphocyte activity as mechanisms related-outcomes. We discussed the results with respect to possible mechanisms that promote survival. RESULTS: Thirteen articles were included. The effects of Tol-DCs induced by five methods on allograft survival were different. Survival by each method was prolonged as follows: allopeptide-pulsed Tol-DCs (42.14 ± 44 days, drug intervention (39 days, mesenchymal stem cell induction (23 days, genetic modification (8.99 ± 4.75 days, and other derivation (2.61 ± 6.98 days. The results indicate that Tol-DC dose and injection influenced graft survival. Single-dose injections of 10(4 Tol-DCs were the most effective for allograft survival, and multiple injections were not superior. Tol-DCs were also synergistic with immunosuppressive drugs or costimulation inhibitors. Possible mechanisms include donor specific T cell hyporesponsiveness, Th2 differentiation, Treg induction, cytotoxicity against allograft reduction, and chimerism induction. CONCLUSIONS: Tol-DCs induced by five methods prolong MHC mismatched islet allograft survival to different degrees, but allopeptide-pulsed host DCs

  20. 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.

  1. Homozygosity at the major histocompatibility complex is required for optimal immunogenicity of bone marrow cell allografts in irradiated rats

    International Nuclear Information System (INIS)

    Hemopoietic histocompatibility (Hh) genes associated with the H-2 region control the antigenicity of hemopoietic cell grafts in the mouse. We have tested for similar genes in rats. Wistar Furth (WF,RTl sup(u)) or Lewis (LEW RTl1) bone marrow cell grafts did not profilerate in spleens of lethally irradiated (WFxLEW) Fl hybrid rats as assessed by measuring the incorporation of 5-iodo-2' deoxyuridine-125I(IUdR) into recipient spleens 5 days after transplantation. In contrast, (WFxLEW)Fl hybrid marrow cells grew well in both WF and LEW parental strain hosts. (WFxDA)Fl or (WFxLEW)Fl hybrid rats were backcrossed to WF parental strain rats to produce progeny, either homozygous, or heterozygous for the MHC. The RTl type of 46 individual backcross progeny was determined using a 5 day mixed-lymphocyte reaction (MLR). Correlation between RTl type and growth of marrow grafts of individual backcross rats was determined bt using each rat as bone marrow donor for irrdiated LEW hosts. Marrow grafts from rats heterozygous for RTl were accepted in all 25 cases, whereas, grafts from 19 of 21 homozygous donors were rejected by the LEW hosts. Thus, homozygosity, for Hh determinants in or near the RTl region appears to be necessary for optimal immunogenicity of bone marrow allografts. (author)

  2. The effect of bone allografts combined with bone marrow stromal cells on the healing of segmental bone defects in a sheep model

    OpenAIRE

    Fernandes, Marco Bernardo C; Guimarães, João Antônio Matheus; Casado, Priscila Ladeira; Cavalcanti, Amanda dos Santos; Gonçalves, Natalia N; Carlos E. Ambrósio; Rodrigues, Fernando; Pinto, Ana Carolina F; Miglino, Maria Angélica; Duarte, Maria Eugênia L.

    2014-01-01

    Background The repair of large bone defects is a major orthopedic challenge because autologous bone grafts are not available in large amounts and because harvesting is often associated with donor-site morbidity. Considering that bone marrow stromal cells (BMSC) are responsible for the maintenance of bone turnover throughout life, we investigated bone repair at a site of a critically sized segmental defect in sheep tibia treated with BMSCs loaded onto allografts. The defect was created in the ...

  3. Limbal Stem Cell Allografts and Corneal Transplant in a Patient with Severe Corneal Melting and Perforation due to Thermokeratoplasty andCross-Linking Treatment Burn

    Directory of Open Access Journals (Sweden)

    Leopoldo Garduño-Vieyra

    2012-10-01

    Full Text Available Purpose: To report corneal stem cell allografts in a patient with a persistent epithelial defect as well as corneal melting and perforation due to severe ultraviolet light burn and thermokeratoplasty treatment for keratoconus. Methods: A 21-year-old female patient with corneal melting, perforation and a persistent epithelial defect in her left eye secondary to iatrogenic treatment for keratoconus, thermokeratoplasty and cross-linking was treated with penetrating keratoplasty, using a 9.0-mm diameter corneal graft and limbal stem cell allograft implants. At the end of the procedure, subtenonian injections of a combination of bevacizumab and triamcinolone were given. Results: The patient had a favorable outcome 48 h after surgery, with an improvement of symptoms and a complete corneal healing. By the third week after surgery, she had a best-corrected visual acuity of 20/60 and a clear corneal graft, which remained stable for the 9 months of follow-up. Conclusions: Treatment with limbal stem cell allografts and penetrating keratoplasty in a female patient with a large corneal defect and melting in her left eye was effective. Larger studies are warranted to explore the real impact of this procedure.

  4. Bilateral diffuse pulmonary ectopic ossification after marrow allograft in a dog. Evidence for allotransplantation of hemopoietic and mesenchymal stem cells

    International Nuclear Information System (INIS)

    In light of recent studies showing successful transplantation of both bony and stromal elements by marrow transplantation, we report an unexpected phenomenon occurring in a canine radiation chimera. Nine hundred fifty-six days after a successful and uneventful DLA-matched marrow allograft, a dog suddenly died of respiratory failure. Autopsy revealed extensive ossification of the lungs with multiple sites of trilineage marrow engraftment. The entire complement of bony elements can apparently be allografted using marrow grafting techniques

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

    Directory of Open Access Journals (Sweden)

    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

  6. 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.

  7. Mitomycin C-treated antigen-presenting cells as a tool for control of allograft rejection and autoimmunity: from bench to bedside.

    Science.gov (United States)

    Terness, Peter; Kleist, Christian; Simon, Helmut; Sandra-Petrescu, Flavius; Ehser, Sandra; Chuang, Jing-Jing; Mohr, Elisabeth; Jiga, Lucian; Greil, Johann; Opelz, Gerhard

    2009-07-01

    Cells have been previously used in experimental models for tolerance induction in organ transplantation and autoimmune diseases. One problem with the therapeutic use of cells is standardization of their preparation. We discuss an immunosuppressive strategy relying on cells irreversibly transformed by a chemotherapeutic drug. Dendritic cells (DCs) of transplant donors pretreated with mitomycin C (MMC) strongly prolonged rat heart allograft survival when injected into recipients before transplantation. Likewise, MMC-DCs loaded with myelin basic protein suppressed autoreactive T cells of MS patients in vitro and prevented experimental autoimmune encephalitis in mice. Comprehensive gene microarray analysis identified genes that possibly make up the suppressive phenotype, comprising glucocorticoid leucine zipper, immunoglobulin-like transcript 3, CD80, CD83, CD86, and apoptotic genes. Based on these findings, a hypothetical model of tolerance induction by MMC-treated DCs is delineated. Finally, we describe the first clinical application of MMC-treated monocyte-enriched donor cells in an attempt to control the rejection of a haploidentical stem cell transplant in a sensitized recipient and discuss the pros and cons of using MMC-treated antigen-presenting cells for tolerance induction. Although many questions remain, MMC-treated cells are a promising clinical tool for controlling allograft rejection and deleterious immune responses in autoimmune diseases. PMID:19393276

  8. Automatic fabrication of 3-dimensional tissues using cell sheet manipulator technique.

    Science.gov (United States)

    Kikuchi, Tetsutaro; Shimizu, Tatsuya; Wada, Masanori; Yamato, Masayuki; Okano, Teruo

    2014-03-01

    Automated manufacturing is a key for tissue-engineered therapeutic products to become common-place and economical. Here, we developed an automatic cell sheet stacking apparatus to fabricate 3-dimensional tissue-engineered constructs exploiting our cell sheet manipulator technique, where cell sheets harvested from temperature-responsive culture dishes are stacked into a multilayered cell sheet. By optimizing the stacking conditions and cell seeding conditions, the apparatus was eventually capable of reproducibly making five-layer human skeletal muscle myoblast (HSMM) sheets with a thickness of approximately 70-80 μm within 100 min. Histological sections and confocal topographies of the five-layer HSMM sheets revealed a stratified structure with no delamination. In cell counts using trypsinization, the live cell numbers in one-, three- and five-layer HSMM sheets were equivalent to the seeded cell numbers at 1 h after the stacking processes; however, after subsequent 5-day static cultures, the live cell numbers of the five-layered HSMM sheets decreased slightly, while one- and three-layer HSMM sheets maintained their live cell numbers. This suggests that there are thickness limitations in maintaining tissues in a static culture. We concluded that by combining our cell sheet manipulator technique and industrial robot technology we can create a secure, cost-effective manufacturing system able to produce tissue-engineered products from cell sheets. PMID:24370007

  9. 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. PMID:26150714

  10. 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...

  11. 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

  12. Role of the spleen in cell-mediated cardiac allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    Hall, B.M.

    1982-04-01

    A quantitative adoptive transfer assay was used to investigate the role of the spleen in cell-mediated rejection of directly vascularized heart grafts. In this assay, the cell-mediated rejection response can be examined directly by testing the capacity of inocula of T cells to effect rejection of DA heart grafts in PVG rats whose own lymphocytes have been destroyed by whole body irradiation. The capacity of a variety of inocula, including lymph node cells (LNCs), spleen cells, and T cells from lymph node and spleen, to restore rejection were compared in groups of splenectomized and nonsplenectomized hosts. In both groups all inocula restored rejection toward normal. Only in experiments testing inocula equivalent to a small fraction of the naive peripheral lymphocyte pool was rejection delayed in the splenectomized hosts, and this was only a delay of a few days. These results showed that in the absence of the spleen, the primary rejection responses can be generated. In addition, it was demonstrated that the normal spleen contains only a small fraction of the T cell pool with the capacity to effect rejection. Memory T cells were also shown to mediate rejection in splenectomized hosts. It is concluded that with strongly incompatible grafts, splenectomy has only a trivial immunosuppressive effect; it removes neither a sigificant proportion of the alloreactive T cell pool nor the essential site for activation of proliferation of these cells.

  13. 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. PMID:27112509

  14. 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.

  15. 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.

  16. 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.

  17. Hepatitis B transmission by cell and tissue allografts: How safe is safe enough?

    OpenAIRE

    Solves, Pilar; Mirabet, Vicente; Alvarez, Manuel

    2014-01-01

    More than 2 million human tissue transplants (bone, tendon, cartilage, skin, cornea, amniotic membrane, stem cells, heart valve, blood vessel, etc.), are performed worldwide every year. Cells and tissues are shared between countries which have different regulations and laboratory equipment and represent a risk of hepatitis B virus (HBV) transmission that has become a global safety concern. While the risk of transfusion-transmitted HBV infection from blood donations has been estimated, the rat...

  18. Autologous Bone Marrow Stem Cells combined with Allograft Cancellous Bone in Treatment of Nonunion

    OpenAIRE

    Le Thua Trung Hau; Duc Phu Bui; Nguyen Duy Thang; Pham Dang Nhat; Le Quy Bao; Nguyen Phan Huy; Tran Ngoc Vu; Le Phuoc Quang; Boeckx willy Denis; Mey Albert De

    2015-01-01

    Autologous cancellous bone graft is currently used as a gold standard method for treatment of bone nonunion. However, there is a limit to the amount of autologous cancellous bone that can be harvested and the donor site morbidity presents a major disadvantage to autologous bone grafting. Embedding viable cells within biological scaffolds appears to be extremely promising. The purpose of this study was to assess the outcome of autologous bone marrow stem cells combined with a cancellous bone a...

  19. 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.

  20. Allografting and the T cell system : a multiparameter analysis of rejection in the rat

    NARCIS (Netherlands)

    P. Joling (Pieter)

    1987-01-01

    textabstractThis thesis describes an experimental study of the T cell system in relation with allogeneic organ transplantation. The experiments were performed in rats. Inbred rat strains as well as congenic rat strains are readily available. These inbred strains enable transplantation in fixed donor

  1. 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.

  2. Down regulation of genes involved in T cell polarity and motility during the induction of heart allograft tolerance by allochimeric MHC I.

    Directory of Open Access Journals (Sweden)

    Wojciech Lisik

    Full Text Available BACKGROUND: The allochimeric MHC class I molecule [alpha1h1/u]-RT1.Aa that contains donor-type (Wistar Furth, WF; RT1u epitopes displayed on recipient-type (ACI, RT1a administered in conjunction with sub-therapeutic dose of cyclosporine (CsA induces indefinite survival of heterotopic cardiac allografts in rat model. In vascularized transplantation models, the spleen contributes to graft rejection by generating alloantigen reactive T cells. The immune response in allograft rejection involves a cascade of molecular events leading to the formation of immunological synapses between T cells and the antigen-presenting cells. METHODOLOGY/PRINCIPAL FINDINGS: To elucidate the molecular pathways involved in the immunosuppressive function of allochimeric molecule we performed microarray and quantitative RTPCR analyses of gene expression profile of splenic T cells from untreated, CsA treated, and allochimeric molecule + subtherapeutic dose of CsA treated animals at day 1, 3 and 7 of post transplantation. Allochimeric molecule treatment caused down regulation of genes involved in actin filament polymerization (RhoA and Rac1, cell adhesion (Catna1, Vcam and CD9, vacuolar transport (RhoB, Cln8 and ATP6v1b2, and MAPK pathway (Spred1 and Dusp6 involved in tubulin cytoskeleton reorganization and interaction between actin and microtubule cytoskeleton. All these genes are involved in T cell polarity and motility, i.e., their ability to move, scan and to form functional immunological synapse with antigen presenting cells (APCs. CONCLUSIONS: These results indicate that the immunosuppressive function of allochimeric molecule may depend on the impairment of T cells' movement and scanning ability, and possibly also the formation of immunological synapse. We believe that these novel findings may have important clinical implications for organ transplantation.

  3. 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.

  4. 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.

  5. Fabrication of a thermoresponsive cell culture dish: a key technology for cell sheet tissue engineering

    OpenAIRE

    Jun Kobayashi and Teruo Okano

    2010-01-01

    This article reviews the properties and characterization of an intelligent thermoresponsive surface, which is a key technology for cell sheet-based tissue engineering. Intelligent thermoresponsive surfaces grafted with poly(N-isopropylacrylamide) exhibit hydrophilic/hydrophobic alteration in response to temperature change. Cultured cells are harvested on thermoresponsive cell culture dishes by decreasing the temperature without the use of digestive enzymes or chelating agents. Our group has d...

  6. 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.

  7. 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.

  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. Antibody-Dependent NK Cell Activation Is Associated with Late Kidney Allograft Dysfunction and the Complement-Independent Alloreactive Potential of Donor-Specific Antibodies.

    Science.gov (United States)

    Legris, Tristan; Picard, Christophe; Todorova, Dilyana; Lyonnet, Luc; Laporte, Cathy; Dumoulin, Chloé; Nicolino-Brunet, Corinne; Daniel, Laurent; Loundou, Anderson; Morange, Sophie; Bataille, Stanislas; Vacher-Coponat, Henri; Moal, Valérie; Berland, Yvon; Dignat-George, Francoise; Burtey, Stéphane; Paul, Pascale

    2016-01-01

    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 (ADCC), 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 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 of

  10. A strategy for organ allografts without using immunosuppressants or irradiation

    OpenAIRE

    Morita, Haruo; Sugiura, Kikuya; Inaba, Muneo; Jin, Tienan; Ishikawa, Junji; Lian, Zhexiong; Adachi, Yasushi; Sogo, Shinji; Yamanishi, Kazuya; Taki, Hideo; Adachi, Masakazu; Noumi, Takato; Kamiyama, Yasuo; Good, Robert A.; Ikehara, Susumu

    1998-01-01

    A strategy to achieve regular and long lasting organ and tissue allografts without using immunosuppressants and/or irradiation has been established for mice. One hundred percent of skin allografts can be induced to survive >350 days after transplantation if spleen cells from the same donors are first injected into the portal vein of the recipients. The mechanisms underlying this long-term tolerance induction can be described as follows: (i) donor T cells from the spleen of the donor facilitat...

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

    International Nuclear Information System (INIS)

    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-γ 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+CD25highFoxp3+ 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.

  12. 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.

  13. 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.

  14. 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. PMID:26929119

  15. In vivo vascularization of cell sheets provided better long-term tissue survival than injection of cell suspension.

    Science.gov (United States)

    Takeuchi, Ryohei; Kuruma, Yosuke; Sekine, Hidekazu; Dobashi, Izumi; Yamato, Masayuki; Umezu, Mitsuo; Shimizu, Tatsuya; Okano, Teruo

    2016-08-01

    Cell sheets have shown a remarkable ability for repairing damaged myocardium in clinical and preclinical studies. Although they demonstrate a high degree of viability as engrafted cells in vivo, the reason behind their survivability is unclear. In this study, the survival and vascularization of rat cardiac cell sheets transplanted in the subcutaneous tissue of athymic rats were investigated temporally. The cell sheets showed significantly higher survival than cell suspensions for up to 12 months, using an in vivo bioluminescence imaging system to detect luciferase-positive transplanted cells. Terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay also showed a smaller number of apoptotic cells in the cell sheets than in the cell suspensions at 1 day. Rapid vascular formation and maturation were observed inside the cell sheets using an in vivo imaging system. Leaky vessels appeared at 6 h, red blood cells flowing through functional vessels appeared at 12 h, and morphologically matured vessels appeared at 7 days. In addition, immunostaining of cell sheets with nerve/glial antigen-2 (NG2) showed that vessel maturity increased over time. Interestingly, these results correlated with the dynamics of cell sheet mRNA expression. Genes related to endothelial cells (ECs) proliferation, migration and vessel sprouting were highly expressed within 1 day, and genes related to pericyte recruitment and vessel maturation were highly expressed at 3 days or later. This suggested that the cell sheets could secrete appropriate angiogenic factors in a timely way after transplantation, and this ability might be a key reason for their high survival. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24470393

  16. Cellular basis of allograft rejection in vivo. III. Restoration of first-set rejection of heart grafts by T helper cells in irradiated rats

    Energy Technology Data Exchange (ETDEWEB)

    Hall, B.M.; de Saxe, I.; Dorsch, S.E.

    1983-12-01

    An adoptive transfer model was used to examine the subpopulations of lymphocytes required to effect first-set rejection of directly vascularized heart allografts. PVG heart grafts are not rejected in irradiated DA hosts for at least 50 days. The adoptive transfer of 5 X 10(7) syngeneic lymph node cells (LNC) restores rejection to 14.4 +/- 2.4 days (mean +/- SD). Subpopulations of LNC, were separated by an indirect ''panning'' technique using the mouse antirat monoclonal antibodies W3/13, MRC OX8, or W3/25 to deplete the unwanted subsets of cells. Each subpopulation was tested, in a number equivalent to the number present in 5 X 10(7) normal LNC, for its ability to cause the rejection of heart grafts. Whole T cells (W3/13+) or helper/inducer T cells (W3/25+) restored graft rejection to 16.4 +/- 3.8 d and 16.0 +/- 2.4 days, respectively. Neither cytotoxic/suppressor T cells (MRC OX8+) nor B cells (Ig+) restored rejection. Indirect immunoperoxidase stains of the grafts showed that although W3/25+ cells predominated in the rejected tissue, MRC OX8+ cells were also present even in grafts from rats restored with inocula that contained less than 1% MRC OX8+ cells. Examination of lymphoid tissues suggested that the MRC OX8+ cells might be of host origin. By the time the grafts were rejected in irradiated hosts, significant thymic regeneration had occurred and there were large numbers of MRC OX8+ cells present in the thymus, as well as some in lymph nodes and spleen.

  17. Polycrystalline Silicon Sheets for Solar Cells by the Improved Spinning Method

    Science.gov (United States)

    Maeda, Y.; Yokoyama, T.; Hide, I.

    1984-01-01

    Cost reduction of silicon materials in the photovoltaic program of materials was examined. The current process of producing silicon sheets is based entirely on the conventional Czochralski ingot growth and wafering used in the semiconductor industry. The current technology cannot meet the cost reduction demands for producing low cost silicon sheets. Alternative sheet production processes such as unconventional crystallization are needed. The production of polycrystalline silicon sheets by unconventional ingot technology is the casting technique. Though large grain sheets were obtained by this technique, silicon ribbon growth overcomes deficiencies of the casting process by obtaining the sheet directly from the melt. The need to solve difficulties of growth stability and impurity effects are examined. The direct formation process of polycrystalline silicon sheets with large grain size, smooth surface, and sharp edges from the melt with a high growth rate which will yield low cost silicon sheets for solar cells and the photovoltaic characteristics associated with this type of sheet to include an EBIC study of the grain boundaries are described.

  18. Cryopreservation of Cell Sheets of Adipose Stem Cells: Limitations and Successes

    OpenAIRE

    Prata, F. P.; M.T. Cerqueira; Moreira-Silva, J.; Pirraco, Rogério P.; Reis, R. L.; Marques, A.P.

    2014-01-01

    Cell Sheets of hASCs (hASCs-CS) have been previously proposed for wound healing applications(1, 2) and despite the concern for production time reduction, the possibility of having these hASCs-CS off-the-shelf is appealing. The goal of this work was to define a cryopreservation methodology allowing to preserve cells viability and the properties CS matrix. hASCs-CS obtained from three different donors were created in UP-cell thermoresponsive dishes(Nunc, Germany) as previously reported(1,...

  19. 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.

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

    OpenAIRE

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

    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 d...

  1. 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.

  2. Role of anti-vimentin antibodies in allograft rejection.

    Science.gov (United States)

    Rose, Marlene L

    2013-11-01

    Production of anti-vimentin antibodies (AVA) after solid organ transplantation are common. Although classically thought to be expressed mainly within the cytosol, recent evidence demonstrates that extracellular or cell surface expression of vimentin is not unusual. This review examines the evidence to assess whether AVA contribute to allograft pathology. Clinical studies suggest that AVA are associated with cardiac allograft vasculopathy in heart transplant recipients. Studies in non-human primates confirm that production of AVA after renal and heart transplantation are not inhibited by Cyclosporine. Experimental studies have demonstrated that mice pre-immunised with vimentin undergo accelerated acute rejection and vascular intimal occlusion of cardiac allografts. Adoptive transfer of hyperimmune sera containing AVA into B-cell-knock-out mice caused accelerated rejection of allografted hearts, this is clear evidence that antibodies to vimentin accelerate rejection. AVA act in concert with the alloimmune response and AVA do not damage syngeneic or native heart allografts. Confocal microscopy of allografted organs in vimentin immunised mice shows extensive expression of vimentin on endothelial cells, apoptotic leukocytes and platelet/leukocyte conjugates, co-localising with C4d. One explanation for the ability of AVA to accelerate rejection would be fixation of complement within the graft and subsequent pro-inflammatory effects; there may also be interactions with platelets within the vasculature.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. A noninvasive transfer system for polarized renal tubule epithelial cell sheets using temperature-responsive culture dishes

    Directory of Open Access Journals (Sweden)

    Kushida A.

    2005-08-01

    Full Text Available We used temperature-responsive culture dishes onto which the temperature-responsive polymer, poly(Nisopropylacrylamide, was covalently grafted for tissue engineering. Confluent cells harvested as intact sheets from these surfaces by simple temperature reduction can be transferred to various surfaces including additional culture dishes, other cell sheets, and tissues. In order to examine the maintenance of cell polarity, Madin-Darby canine kidney cells and human primary renal proximal tubule epithelial cells which had developed apical-basal cell polarity in culture, were subjected to cell sheet transfer. This functional and structural cell polarity, which is susceptible to treatment with trypsin, was examined by immunohistochemistry and transmission electron microscopy. Using our cell-sheet method, the noninvasive transfer of these cell sheets retaining typical distributions of Na+/K+-ATPase, GLUT-1, SGLT-1, aquaporin-1, neutral endopeptidase and dipeptidylendopeptidase IV, could be achieved. The transferred cell sheets also developed numerous microvilli and tight junctions at the apical and lateral membranes, respectively. For biochemical analysis, immunoblotting of occludin, a transmembrane protein that composes tight junctions, was conducted and results confirmed that occludin remained intact after cell sheet transfer. This two-dimensional cell sheet manipulation method promises to be useful for tissue engineering as well as in the investigation of epithelial cell polarity.

  8. 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.

  9. 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.

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

    DEFF Research Database (Denmark)

    Koefoed, Mette; Ito, Hiromu; Gromov, Kirill;

    2005-01-01

    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...... 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 rAAV-Lac...

  11. Abrogation of bone marrow allograft resistance in mice by increased total body irradiation correlates with eradication of host clonable T cells and alloreactive cytotoxic precursors

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, E.; Lapidot, T.; Gozes, D.; Singer, T.S.; Reisner, Y.

    1987-01-15

    Host-vs-graft activity presents a major obstacle for transplantation of T cell-depleted bone marrow in HLA-mismatched patients. In a primate model, conditioned exactly like leukemia patients, it was shown that residual host clonable T cells, as well as alloreactive cytotoxic precursors, were present in peripheral blood and spleen after completion of cytoreduction. We have now extended this study in a mouse model for allogeneic bone marrow transplantation. C/sub 3/H/HeJ mice were treated by 9 Gy total body irradiation (TBI), and 24 hr later their spleen cells were cultured in the presence of T cell growth factor and phytohemagglutinin according to the limit dilution procedure. After 7 days of culture the average frequency of clonable cells was 2.5 X 10(-3) compared with 37 X 10(-3) in the spleens of normal mice. The T cell derivation of the growing cells was ascertained by complement-mediated cytotoxicity with anti-Thy-1 as well as with anti-Lyt-2 and anti-Ly-3T4. In parallel, we found that the initial engraftment rate of bone marrow allograft in mice given 9 Gy TBI was lower than that found in recipients of syngeneic marrow. The initial engraftment rate was measured by the number of colony-forming units in the spleen and by splenic uptake of /sup 125/IUdR. A slight increase in TBI from 9 Gy to 11 Gy markedly reduced the difference in the number of spleen colony-forming units or the IUdR uptake between recipients of allogeneic and syngeneic bone marrow. This increase in TBI also coincided with eradication of detectable clonable T cells. Moreover, in mice transplanted with T cell-depleted bone marrow after 9 Gy TBI, we also demonstrate that cytotoxicity against donor-type target cells is present in the spleen 10 to 14 days posttransplantation, whereas in mice treated by 11 Gy TBI such alloreactivity could not be detected.

  12. 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.

  13. Rapid fabricating technique for multi-layered human hepatic cell sheets by forceful contraction of the fibroblast monolayer.

    Directory of Open Access Journals (Sweden)

    Yusuke Sakai

    Full Text Available Cell sheet engineering is attracting attention from investigators in various fields, from basic research scientists to clinicians focused on regenerative medicine. However, hepatocytes have a limited proliferation potential in vitro, and it generally takes a several days to form a sheet morphology and multi-layered sheets. We herein report our rapid and efficient technique for generating multi-layered human hepatic cell (HepaRG® cell sheets using pre-cultured fibroblast monolayers derived from human skin (TIG-118 cells as a feeder layer on a temperature-responsive culture dish. Multi-layered TIG-118/HepaRG cell sheets with a thick morphology were harvested on day 4 of culturing HepaRG cells by forceful contraction of the TIG-118 cells, and the resulting sheet could be easily handled. In addition, the human albumin and alpha 1-antitrypsin synthesis activities of TIG-118/HepaRG cells were approximately 1.2 and 1.3 times higher than those of HepaRG cells, respectively. Therefore, this technique is considered to be a promising modality for rapidly fabricating multi-layered human hepatocyte sheets from cells with limited proliferation potential, and the engineered cell sheet could be used for cell transplantation with highly specific functions.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. The PLUTO reactor at Harwell, U.K. and ancillary hot cell facilities. Information sheets

    International Nuclear Information System (INIS)

    Technical information is given on the PLUTO reactor and associated hot cell facilities, with the main emphasis on experimental irradiation facilities and specialized irradiation devices (loops and capsules). The information is presented in the form of five information sheets under the headings; main characteristics of the reactor; utilization and specialization of the reactor; experimental facilities; neutron spectra; main characteristics of specialized irradiation devices

  19. πSPIM: high NA high resolution isotropic light-sheet imaging in cell culture dishes.

    Science.gov (United States)

    Theer, Patrick; Dragneva, Denitsa; Knop, Michael

    2016-01-01

    Light-sheet fluorescence microscopy (LSFM), also termed single plane illumination microscopy (SPIM), enables live cell fluorescence imaging with optical sectioning capabilities superior to confocal microscopy and without any out-of-focus exposure of the specimen. However, the need of two objective lenses, one for light-sheet illumination and one for imaging, imposes geometrical constraints that require LSFM setups to be adapted to the specific needs of different types of specimen in order to obtain optimal imaging conditions. Here we demonstrate the use of an oblique light-sheet configuration adapted to provide the highest possible Gaussian beam enabled resolution in LSFM. The oblique light-sheet configuration furthermore enables LSFM imaging at the surface of a cover slip, without the need of specific sample mounting. In addition, the system is compatible with simultaneous high NA wide-field epi-fluorescence imaging of the specimen contained in a glass-bottom cell culture dish. This prevents cumbersome sample mounting and enables rapid screening of large areas of the specimen followed by high-resolution LSFM imaging of selected cells. We demonstrate the application of this microscope for in toto imaging of endocytosis in yeast, showing for the first time imaging of all endocytic events of a given cell over a period of >5 minutes with sub-second resolution. PMID:27619647

  20. 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

  1. NREL Spurred the Success of Multijunction Solar Cells (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2013-08-01

    Many scientists once believed that high-quality gallium indium phosphide (GaInP) alloys could not be grown for use as semiconductors because the alloys would separate. However, researchers at the National Renewable Energy Laboratory (NREL) thought differently, and they employed GaInP in a material combination that allowed the multijunction cell to flourish. The multijunction cell is now the workhorse that powers satellites and the catalyst for renewed interest in concentrator photovoltaic products.

  2. 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. 

  3. Controlling Arteriogenesis and Mast Cells Are Central to Bioengineering Solutions for Critical Bone Defect Repair Using Allografts

    Directory of Open Access Journals (Sweden)

    Ben Antebi

    2016-01-01

    Full Text Available Although most fractures heal, critical defects in bone fail due to aberrant differentiation of mesenchymal stem cells towards fibrosis rather than osteogenesis. While conventional bioengineering solutions to this problem have focused on enhancing angiogenesis, which is required for bone formation, recent studies have shown that fibrotic non-unions are associated with arteriogenesis in the center of the defect and accumulation of mast cells around large blood vessels. Recently, recombinant parathyroid hormone (rPTH; teriparatide; Forteo therapy have shown to have anti-fibrotic effects on non-unions and critical bone defects due to inhibition of arteriogenesis and mast cell numbers within the healing bone. As this new direction holds great promise towards a solution for significant clinical hurdles in craniofacial reconstruction and limb salvage procedures, this work reviews the current state of the field, and provides insights as to how teriparatide therapy could be used as an adjuvant for healing critical defects in bone. Finally, as teriparatide therapy is contraindicated in the setting of cancer, which constitutes a large subset of these patients, we describe early findings of adjuvant therapies that may present future promise by directly inhibiting arteriogenesis and mast cell accumulation at the defect site.

  4. 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.

  5. 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...

  6. 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.

  7. 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

  8. 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

  9. Recipient-derived EDA fibronectin promotes cardiac allograft fibrosis.

    Science.gov (United States)

    Booth, Adam J; Wood, Sherri C; Cornett, Ashley M; Dreffs, Alyssa A; Lu, Guanyi; Muro, Andrés F; White, Eric S; Bishop, D Keith

    2012-03-01

    Advances in donor matching and immunosuppressive therapies have decreased the prevalence of acute rejection of cardiac grafts; however, chronic rejection remains a significant obstacle for long-term allograft survival. While initiating elements of anti-allograft immune responses have been identified, the linkage between these factors and the ultimate development of cardiac fibrosis is not well understood. Tissue fibrosis resembles an exaggerated wound healing response, in which extracellular matrix (ECM) molecules are central. One such ECM molecule is an alternatively spliced isoform of the ubiquitous glycoprotein fibronectin (FN), termed extra domain A-containing cellular fibronectin (EDA cFN). EDA cFN is instrumental in fibrogenesis; thus, we hypothesized that it might also regulate fibrotic remodelling associated with chronic rejection. We compared the development of acute and chronic cardiac allograft rejection in EDA cFN-deficient (EDA(-/-)) and wild-type (WT) mice. While EDA(-/-) mice developed acute cardiac rejection in a manner indistinguishable from WT controls, cardiac allografts in EDA(-/-) mice were protected from fibrosis associated with chronic rejection. Decreased fibrosis was not associated with differences in cardiomyocyte hypertrophy or intra-graft expression of pro-fibrotic mediators. Further, we examined expression of EDA cFN and total FN by whole splenocytes under conditions promoting various T-helper lineages. Conditions supporting regulatory T-cell (Treg) development were characterized by greatest production of total FN and EDA cFN, though EDA cFN to total FN ratios were highest in Th1 cultures. These findings indicate that recipient-derived EDA cFN is dispensable for acute allograft rejection responses but that it promotes the development of fibrosis associated with chronic rejection. Further, conditions favouring the development of regulatory T cells, widely considered graft-protective, may drive production of ECM molecules which enhance

  10. 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

  11. 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, incubation stage of EP and histopathologic manifestations showed that the group with transplanted OECs regained more improvement in hindlimb than the control group. Conclusion The OECs of two sources have the same ability to regain and improve the axonal function which can promote axons regeneration of SCI.

  12. 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.

  13. Preventing Allograft Rejection by Targeting Immune Metabolism

    Directory of Open Access Journals (Sweden)

    Chen-Fang Lee

    2015-10-01

    Full Text Available Upon antigen recognition and co-stimulation, T lymphocytes upregulate the metabolic machinery necessary to proliferate and sustain effector function. This metabolic reprogramming in T cells regulates T cell activation and differentiation but is not just a consequence of antigen recognition. Although such metabolic reprogramming promotes the differentiation and function of T effector cells, the differentiation of regulatory T cells employs different metabolic reprogramming. Therefore, we hypothesized that inhibition of glycolysis and glutamine metabolism might prevent graft rejection by inhibiting effector generation and function and promoting regulatory T cell generation. We devised an anti-rejection regimen involving the glycolytic inhibitor 2-deoxyglucose (2-DG, the anti-type II diabetes drug metformin, and the inhibitor of glutamine metabolism 6-diazo-5-oxo-L-norleucine (DON. Using this triple-drug regimen, we were able to prevent or delay graft rejection in fully mismatched skin and heart allograft transplantation models.

  14. 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.

  15. 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).

  16. Temperature-responsive intelligent interfaces for biomolecular separation and cell sheet engineering.

    Science.gov (United States)

    Nagase, Kenichi; Kobayashi, Jun; Okano, Teruo

    2009-06-01

    Temperature-responsive intelligent surfaces, prepared by the modification of an interface with poly(N-isopropylacrylamide) and its derivatives, have been used for biomedical applications. Such surfaces exhibit temperature-responsive hydrophilic/hydrophobic alterations with external temperature changes, which, in turn, result in thermally modulated interactions with biomolecules and cells. In this review, we focus on the application of these intelligent surfaces to chromatographic separation and cell cultures. Chromatographic separations using several types of intelligent surfaces are mentioned briefly, and various effects related to the separation of bioactive compounds are discussed, including wettability, copolymer composition and graft polymer architecture. Similarly, we also summarize temperature-responsive cell culture substrates that allow the recovery of confluent cell monolayers as contiguous living cell sheets for tissue-engineering applications. The key factors in temperature-dependent cell adhesion/detachment control are discussed from the viewpoint of grafting temperature-responsive polymers, and new methodologies for effective cell sheet culturing and the construction of thick tissues are summarized. PMID:19324682

  17. Lumped series resistance of solar cells as a result of distributed sheet resistance

    Science.gov (United States)

    Sokolić, Saša; Križaj, Dejan; Amon, Slavko

    1993-04-01

    An analysis of solar cell distributed sheet resistance is performed by solving the nonlinear Poisson equation for the surface potential. Two different approaches to lumped series resistance are discussed: equivalent series resistance RSeq obtained from the cell's equivalent circuit that satisfies the actual current of the cell (all other parameters in the equivalent circuit except the series resistance are kept constant) and Joule series resistance RSJ obtained from the Joule losses in the emitter of the cell. It is observed that the I( U) characteristic obtained from the equivalent circuit that includes RSJ generally disagrees with the actual I( U) characteristic of the solar cell. An additional series resistance RSadd should be introduced in series with RSJ. Series resistances RSJ, Sadd and RSeq are analyzed numerically in one and two dimensions for different conditions of terminal voltage, illumination and weighted sheet resistance Rshb2, where b is related to the geometry of the analyzed cell. Following the derivations and the results of the numerical analysis it can be concluded that wherever RSJ varies as a function of terminal voltage, RSadd should be taken into consideration.

  18. Fabrication of mouse embryonic stem cell-derived layered cardiac cell sheets using a bioreactor culture system.

    Directory of Open Access Journals (Sweden)

    Katsuhisa Matsuura

    Full Text Available Bioengineered functional cardiac tissue is expected to contribute to the repair of injured heart tissue. We previously developed cardiac cell sheets using mouse embryonic stem (mES cell-derived cardiomyocytes, a system to generate an appropriate number of cardiomyocytes derived from ES cells and the underlying mechanisms remain elusive. In the present study, we established a cultivation system with suitable conditions for expansion and cardiac differentiation of mES cells by embryoid body formation using a three-dimensional bioreactor. Daily conventional medium exchanges failed to prevent lactate accumulation and pH decreases in the medium, which led to insufficient cell expansion and cardiac differentiation. Conversely, a continuous perfusion system maintained the lactate concentration and pH stability as well as increased the cell number by up to 300-fold of the seeding cell number and promoted cardiac differentiation after 10 days of differentiation. After a further 8 days of cultivation together with a purification step, around 1 × 10(8 cardiomyocytes were collected in a 1-L bioreactor culture, and additional treatment with noggin and granulocyte colony stimulating factor increased the number of cardiomyocytes to around 5.5 × 10(8. Co-culture of mES cell-derived cardiomyocytes with an appropriate number of primary cultured fibroblasts on temperature-responsive culture dishes enabled the formation of cardiac cell sheets and created layered-dense cardiac tissue. These findings suggest that this bioreactor system with appropriate medium might be capable of preparing cardiomyocytes for cell sheet-based cardiac tissue.

  19. 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.

  20. 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.

  1. High-efficiency cell concepts on low-cost silicon sheets

    Science.gov (United States)

    Bell, R. O.; Ravi, K. V.

    1985-01-01

    The limitations on sheet growth material in terms of the defect structure and minority carrier lifetime are discussed. The effect of various defects on performance are estimated. Given these limitations designs for a sheet growth cell that will make the best of the material characteristics are proposed. Achievement of optimum synergy between base material quality and device processing variables is proposed. A strong coupling exists between material quality and the variables during crystal growth, and device processing variables. Two objectives are outlined: (1) optimization of the coupling for maximum performance at minimal cost; and (2) decoupling of materials from processing by improvement in base material quality to make it less sensitive to processing variables.

  2. Injury to Allografts: innate immune pathways to acute and chronic rejection

    International Nuclear Information System (INIS)

    An emerging body of evidence suggests that innate immunity, as the first line of host defense against invading pathogens or their components [pathogen-associated molecular patterns, (PAMPs)], plays also a critical role in acute and chronic allograft rejection. Injury to the donor organ induces an inflammatory milieu in the allograft, which appears to be the initial key event for activation of the innate immune system. Injury-induced generation of putative endogenous molecular ligand, in terms of damaged/danger-associated molecular patterns (DAMPs) such as heat shock proteins, are recognized by Toll-like receptors (TLRs), a family of pattern recognition receptors on cells of innate immunity. Acute allograft injury (e.g. oxidative stress during donor brain-death condition, post-ischemic reperfusion injury in the recipient) includes DAMPs which may interact with, and activate, innate TLR-bearing dendritic cells (DCs) which, in turn, via direct allo-recognition through donor-derived DCs and indirect allo-recogntion through recipient-derived DCs, initiate the recipient's adaptive alloimmune response leading to acute allograft rejection. Chronic injurious events in the allograft (e.g. hypertension, hyperlipidemia, CMV infection, administration of cell-toxic drugs [calcineurin-inhibitors]) induce the generation of DAMPs, which may interact with and activate innate TLR-bearing vascular cells (endothelial cells, smooth muscle cells) which, in turn, contribute to the development of atherosclerosis of donor organ vessels (alloatherosclerosis), thus promoting chronic allograft rejection. (author)

  3. 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. PMID:27375939

  4. 同种异体器官移植联合造血干细胞移植与免疫耐受%Organ allografts combined with hematopoietic stem cell transplantation and immunotolerance

    Institute of Scientific and Technical Information of China (English)

    代佑果; 黄金燕

    2010-01-01

    Our understanding of the immunological mechanisms of rejection has greatly improved over the past 10 years. The allografts have maintained long survival without immunosuppressive treatment in the several organ-transplant recipients combined with hematopoietic stem cell transplantation. The authors attributed the successful outcome to the cotransplantation of donor stem cells. The review will analyze firstly conditions of the recipients, and then review the theoretical basis and history regarding donor-specific tolerance of allograft, and it will also clarify that there is no direct link between the donor-specific transplantation tolerance and hematopoietic stem cell transplantation.%过去10年,我们对移植免疫排斥机制的理解有了很大提高.在一些同种异体器官移植联合造血干细胞移植的病例,不用免疫抑制剂治疗,受体对移植物仍然保持长期免疫耐受,有作者把这一耐受现象归功于联合了造血干细胞移植.本文就从对这些案例的分析出发,回顾同种异体器官移植后供体特异性移植耐受形成的理论基础和历史沿革,最后阐明供体特异性移植耐受与造血干细胞移植之间并没有直接联系.

  5. Light sheet microscopy for tracking single molecules on the apical surface of living cells.

    Science.gov (United States)

    Li, Yu; Hu, Ying; Cang, Hu

    2013-12-12

    Single particle tracking is a powerful tool to study single molecule dynamics in living biological samples. However, current tracking techniques, which are based mainly on epifluorescence, confocal, or TIRF microscopy, have difficulties in tracking single molecules on the apical surface of a cell. We present here a three-dimensional (3D) single particle tracking technique that is based on prism coupled light-sheet microscopy (PCLSM). This novel design provides a signal-to-noise ratio comparable to confocal microscopy while it has the capability of illuminating at arbitrary depth. We demonstrate tracking of single EGF molcules on the apical surface of live cell membranes from their binding to EGF receptors until they are internalized or photobleached. We found that EGF exhibits multiple diffusion behaviors on live A549 cell membranes. At room temperature, the average diffusion coefficient of EGF on A549 cells was measured to be 0.13 μm(2)/s. Depletion of cellular cholesterol with methyl-β-cyclodextrin leads to a broader distribution of diffusion coefficients and an increase of the average diffusion coefficient at room temperature. This light-sheet based 3D single particle tracking technique solves the technique difficulty of tracking single particles on apical membranes and is able to document the whole "lifetime" of a particle from binding till photobleaching or internalization. PMID:23895420

  6. 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.

  7. 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.

  8. 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. PMID:12735200

  9. Consolidation of massive bone allografts in limb-preserving operations for bone tumours

    OpenAIRE

    San-Julian, M.; Leyes, M.; Mora, G. (Gonzalo); Cañadell, J.M. (J. M.)

    1995-01-01

    This study analysed the influence of several factors affecting the consolidation time of 83 massive bone allografts in 79 patients with malignant bone tumours: osteosarcoma 57; Ewing's sarcoma 8; malignant fibrous histiocytoma 3; chondrosarcoma 4; fibrosarcoma 5; and giant cell tumours 2. The mean age of the patients was 19 years and the mean length of the allografts was 18 cm. The minimum follow up was for 12 months. The mean consolidation time for metaphyseal and diaphyseal osteotomies was ...

  10. Cutting Edge: Acute Lung Allograft Rejection Is Independent of Secondary Lymphoid Organs1

    OpenAIRE

    Gelman, Andrew E.; Li, Wenjun; Richardson, Steven B.; Zinselmeyer, Bernd H.; Lai, Jiaming; Okazaki, Mikio; Kornfeld, Christopher G.; Kreisel, Friederike H.; Sugimoto, Seiichiro; Tietjens, Jeremy R.; Dempster, John; Patterson, G. Alexander; Krupnick, Alexander S.; Miller, Mark J.; Kreisel, Daniel

    2009-01-01

    It is the prevailing view that adaptive immune responses are initiated in secondary lymphoid organs. Studies using alymphoplastic mice have shown that secondary lymphoid organs are essential to initiate allograft rejection of skin, heart, and small bowel. The high immunogenicity of lungs is well recognized and allograft rejection remains a major contributing factor to poor outcomes after lung transplantation. We show in this study that alloreactive T cells are initially primed within lung all...

  11. 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.

  12. 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...... 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. Evaluation of the ion implantation process for production of solar cells from silicon sheet materials

    Science.gov (United States)

    Spitzer, M. B.

    1983-01-01

    The objective of this program is the investigation and evaluation of the capabilities of the ion implantation process for the production of photovoltaic cells from a variety of present-day, state-of-the-art, low-cost silicon sheet materials. Task 1 of the program concerns application of ion implantation and furnace annealing to fabrication of cells made from dendritic web silicon. Task 2 comprises the application of ion implantation and pulsed electron beam annealing (PEBA) to cells made from SEMIX, SILSO, heat-exchanger-method (HEM), edge-defined film-fed growth (EFG) and Czochralski (CZ) silicon. The goals of Task 1 comprise an investigation of implantation and anneal processes applied to dendritic web. A further goal is the evaluation of surface passivation and back surface reflector formation. In this way, processes yielding the very highest efficiency can be evaluated. Task 2 seeks to evaluate the use of PEBA for various sheet materials. A comparison of PEBA to thermal annealing will be made for a variety of ion implantation processes.

  14. 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.

  15. 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

  16. Sphingosine-1-phosphate receptor 1 agonist SEW2871 prolongs heterotopic heart allograft survival in mice.

    Science.gov (United States)

    Ni, Qian; Yuan, Baohong; Liu, Tao; Lan, Fang; Luo, Xiaochun; Lu, Xiaoyan; Huang, Ping; Dai, Liangcheng; Jin, Xiaobao; Yin, Hui

    2015-05-01

    Sphingosine-1-phosphate (S1P) is a biologically active metabolite of plasma-membrane sphingolipids that is essential for immune cell trafficking. Recent studies have revealed immunomodulatory functions of S1P and its receptors (S1PR1-S1PR5) in many inflammatory conditions, such as asthma and autoimmunity. Here, we explore the efficacy of SEW2871, a selective S1PR1 agonist, in the prevention of acute allograft rejection in a murine cardiac transplantation model. Treatment of recipient mice with SEW2871 significantly prolongs cardiac allograft survival as compared to those recipients treated with control vehicle. The enhanced graft survival is associated with reduced circulating lymphocytes and allograft inflammatory cell infiltration. The cytokine analysis showed decreased allograft expression of TNF-α, IFN-γ and IL-2 in the SEW2871-treated mice. Moreover, administration of SEW2871 increases the percentage of CD4(+) T regulatory cells and FoxP3 expression in spleen of allograft recipients. Therefore, SEW2871 plays a critical role in regulation of lymphocyte trafficking and development, which directly contributes to prolongation of the allograft survival. PMID:25776899

  17. 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.

  18. Deformable Graph Model for Tracking Epithelial Cell Sheets in Fluorescence Microscopy.

    Science.gov (United States)

    Zou, Roger S; Tomasi, Carlo

    2016-07-01

    We propose a novel method for tracking cells that are connected through a visible network of membrane junctions. Tissues of this form are common in epithelial cell sheets and resemble planar graphs where each face corresponds to a cell. We leverage this structure and develop a method to track the entire tissue as a deformable graph. This coupled model in which vertices inform the optimal placement of edges and vice versa captures global relationships between tissue components and leads to accurate and robust cell tracking. We compare the performance of our method with that of four reference tracking algorithms on four data sets that present unique tracking challenges. Our method exhibits consistently superior performance in tracking all cells accurately over all image frames, and is robust over a wide range of image intensity and cell shape profiles. This may be an important tool for characterizing tissues of this type especially in the field of developmental biology where automated cell analysis can help elucidate the mechanisms behind controlled cell-shape changes. PMID:26829784

  19. Better Solar Cells and Manufacturing Processes Using NREL's Ultrafast Quantum Efficiency Method (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2011-08-01

    Fact sheet on the FlashQE system, a 2011 R&D 100 Award winner. A solid-state optical system by NREL and Tau Science measures solar cell quantum efficiency in less than a second, enabling a suite of new capabilities for solar cell manufacturers.

  20. Comparison of immune response to nerve allograft segments in fetal and adult rabbits: a histological study.

    Science.gov (United States)

    Ağaoğlu, G; Kayikçioğlu, A; Sargon, M; Erk, Y; Mavili, E

    2000-04-01

    Fetuses, as opposed to adults, are immature immunologically and it has been proved that they can tolerate allograft materials much better than adults. In this study the rejection phenomenon of nerve allografts was compared histologically in fetuses and adults. The study was performed in 60 New Zealand rabbits (30 pregnant and 30 nonpregnant), and allograft nerve segments were obtained from Chinchilla rabbits. The animals were divided into fetal and adult groups. Each group was studied at various time periods. Nerve allografts were placed under the panniculus carnosus in the interscapular region of the fetuses and adults. In both fetal and adult groups, the nerve allograft segments were assessed histologically after 1, 7, and 30 days. The criteria used during the evaluation were the degenerative findings in the myelinated axons (large, medium, and small axons), changes in Schwann's cells, and the quantity of infiltrating cells. The changes were graded microscopically from 0 (no change) to 3 (severe destruction and cellular infiltration). Cellular infiltration was more extensive in the adult groups than in the fetal groups. Earlier fetal groups showed minimal infiltration, but the response became more extensive in the later fetal groups. This is probably related to the removal of the fetuses from their intrauterine environment. When comparing fetal and adult groups, the results were significant (p < 0.05). The fetuses tolerated the nerve allograft segments better than the adults. This may be related to the immature immune system of the fetuses.

  1. 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.

  2. Mechanisms involved in antibody- and complement-mediated allograft rejection

    OpenAIRE

    Wasowska, Barbara A.

    2010-01-01

    Antibody-mediated rejection has become critical clinically because this form of rejection is usually unresponsive to conventional anti-rejection therapy, and therefore, it has been recognized as a major cause of allograft loss. Our group developed experimental animal models of vascularized organ transplantation to study pathogenesis of antibody- and complement-mediated endothelial cell injury leading to graft rejection. In this review, we discuss mechanisms of antibody-mediated graft rejectio...

  3. 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.

  4. Recipient–derived EDA fibronectin promotes cardiac allograft fibrosis

    Science.gov (United States)

    Booth, Adam J; Wood, Sherri C; Cornett, Ashley M; Dreffs, Alyssa A; Lu, Guanyi; Muro, Andrés F; White, Eric S; Bishop, D Keith

    2014-01-01

    Advances in donor matching and immunosuppressive therapies have decreased the prevalence of acute rejection of cardiac grafts; however, chronic rejection remains a significant obstacle for long-term allograft survival. While initiating elements of anti-allograft immune responses have been identified, the linkage between these factors and the ultimate development of cardiac fibrosis is not well understood. Tissue fibrosis resembles an exaggerated wound healing response, in which extracellular matrix (ECM) molecules are central. One such ECM molecule is an alternatively spliced isoform of the ubiquitous glycoprotein fibronectin (FN), termed extra domain A-containing cellular fibronectin (EDA cFN). EDA cFN is instrumental in fibrogenesis; thus, we hypothesized that it might also regulate fibrotic remodelling associated with chronic rejection. We compared the development of acute and chronic cardiac allograft rejection in EDA cFN-deficient (EDA−/−) and wild-type (WT) mice. While EDA−/− mice developed acute cardiac rejection in a manner indistinguishable from WT controls, cardiac allografts in EDA−/− mice were protected from fibrosis associated with chronic rejection. Decreased fibrosis was not associated with differences in cardiomyocyte hypertrophy or intra-graft expression of pro-fibrotic mediators. Further, we examined expression of EDA cFN and total FN by whole splenocytes under conditions promoting various T-helper lineages. Conditions supporting regulatory T-cell (Treg) development were characterized by greatest production of total FN and EDA cFN, though EDA cFN to total FN ratios were highest in Th1 cultures. These findings indicate that recipient-derived EDA cFN is dispensable for acute allograft rejection responses but that it promotes the development of fibrosis associated with chronic rejection. Further, conditions favouring the development of regulatory T cells, widely considered graft-protective, may drive production of ECM molecules which

  5. 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

  6. ROLE OF NUCLEAR FACTOR NF-κB IN ALLOGRAFT REJEKTION

    Directory of Open Access Journals (Sweden)

    N. V. Kuncevich

    2010-01-01

    Full Text Available Nuclear factor kappa B (NF-κB is a rapid response transcription factor for genes whose products are critical for inflammation and immunity. In this review structure and general properties of NF-κB the role of transcription factor NF-κB in allograft rejection are presented. In this review considered the mechanism activation of NF-κB in allograft rejection and its role in following pathological processes: endothelial cells activation, recipient T-cells activation and maturation of dendritic cells (antigen – presenting immune cells. NF-κB – targeted therapeutics approaches, that might be effective in transplantation are presented. 

  7. 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.

  8. Acute Regeneration and Chronic Acellular Transformation of Rabbit Cryopreserved Aortic Allografts

    International Nuclear Information System (INIS)

    An analysis of rabbit cryopreserved aortic allografts excised on postoperative days (POD) 2, 5, 11, 60, 210, 360, and 720, as well as controls that were untransplanted native aortas and cryopreserved aortas, was performed. On POD2, the number of medial smooth muscle cells in the allografts was reduced to approximately 50%. Ki-67 analysis revealed that medial smooth muscle cells in the allografts proliferated from the 2nd day. By the 11th day, their proliferation ceased and the number of medial smooth muscle cells was restored to almost at the same level as in the controls. Polymorphic microsatellite DNA marker analysis disclosed that the restored medial smooth muscle cells were of donor origin. From 7 months through 2 years, the media of cryopreserved aortic allografts were transformed into acellular structures, in which the elastic fibers were preserved. On the other hand, newly accumulated smooth muscle cells were observed in the adventitia just outside of acellular media after 7 months. In some cases, scattered lamellar calcium deposition was observed in the same regions. This study presents a comprehensive documentation of regeneration and acellular transformation in cryopreserved aortic allografts based on short and long-term analysis

  9. 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.

  10. 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.

  11. 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

  12. Autophagy in allografts rejection: A new direction?

    Science.gov (United States)

    Sun, Hukui; Cheng, Dayan; Ma, Yuanyuan; Wang, Huaiquan; Liang, Ting; Hou, Guihua

    2016-03-18

    Despite the introduction of new and effective immunosuppressive drugs, acute cellular graft rejection is still a major risk for graft survival. Modulating the dosage of immunosuppressive drugs is not a good choice for all patients, new rejection mechanisms discovery are crucial to limit the inflammatory process and preserve the function of the transplant. Autophagy, a fundamental cellular process, can be detected in all subsets of lymphocytes and freshly isolated naive T lymphocytes. It is required for the homeostasis and function of T lymphocytes, which lead to cell survival or cell death depending on the context. T cell receptor (TCR) stimulation and costimulator signals induce strong autophagy, and autophagy deficient T cells leads to rampant apoptosis upon TCR stimulation. Autophagy has been proved to be activated during ischemia-reperfusion (I/R) injury and associated with grafts dysfunction. Furthermore, Autophagy has also emerged as a key mechanism in orchestrating innate and adaptive immune response to self-antigens, which relates with negative selection and Foxp3(+) Treg induction. Although, the role of autophagy in allograft rejection is unknown, current data suggest that autophagy indeed sweeps across both in the graft organs and recipients lymphocytes after transplantation. This review presents the rationale for the hypothesis that targeting the autophagy pathway could be beneficial in promoting graft survival after transplantation.

  13. Future of allografts in sports medicine.

    Science.gov (United States)

    Harner, Christopher D; Lo, Marvin Y

    2009-04-01

    Allografts play a prominent role in sports medicine, and their usage has increased dramatically over the past few decades, but the role of allograft in the future of sports medicine largely depends on several factors: (1) the ability of the tissue banking industry to convince both surgeons and the general population that tissue procurement is safe and nearly disease-free, (2) the ability to sterilize tissue with minimal compromise to tissue integrity, (3) successful clinical outcomes with allograft, and (4) the advent of artificial scaffolds and ligaments that function as well. PMID:19306738

  14. 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.

  15. 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. PMID:17920955

  16. 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.

  17. Autologous transplantation of oral mucosal epithelial cell sheets cultured on an amniotic membrane substrate for intraoral mucosal defects.

    Directory of Open Access Journals (Sweden)

    Takeshi Amemiya

    Full Text Available The human amniotic membrane (AM is a thin intrauterine placental membrane that is highly biocompatible and possesses anti-inflammatory and anti-scarring properties. Using AM, we developed a novel method for cultivating oral mucosal epithelial cell sheets. We investigated the autologous transplantation of oral mucosal epithelial cells cultured on AM in patients undergoing oral surgeries. We obtained specimens of AM from women undergoing cesarean sections. This study included five patients without any history of a medical disorder who underwent autologous cultured oral epithelial transplantation following oral surgical procedures. Using oral mucosal biopsy specimens obtained from these patients, we cultured oral epithelial cells on an AM carrier. We transplanted the resultant cell sheets onto the oral mucosal defects. Patients were followed-up for at least 12 months after transplantation. After 2-3 weeks of being cultured on AM, epithelial cells were well differentiated and had stratified into five to seven layers. Immunohistochemistry revealed that the cultured cells expressed highly specific mucosal epithelial cell markers and basement membrane proteins. After the surgical procedures, no infection, bleeding, rejection, or sheet detachment occurred at the reconstructed sites, at which new oral mucous membranes were evident. No recurrence was observed in the long-term follow-up, and the postoperative course was excellent. Our results suggest that AM-cultured oral mucosal epithelial cell sheets represent a useful biomaterial and feasible method for oral mucosal reconstruction. However, our primary clinical study only evaluated their effects on a limited number of small oral mucosal defects.

  18. 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.

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

    Science.gov (United States)

    Silvestri, Ludovico; Paciscopi, Marco; Soda, Paolo; Biamonte, Filippo; Iannello, Giulio; Frasconi, Paolo; Pavone, Francesco S

    2015-01-01

    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 (PCs) 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 PCs 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 PCs. 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 PCs, 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 PCs 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. PMID:26074783

  20. 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.

  1. The effect of the coumarin-like derivative osthole on the osteogenic properties of human periodontal ligament and jaw bone marrow mesenchymal stem cell sheets.

    Science.gov (United States)

    Gao, Li-Na; An, Ying; Lei, Ming; Li, Bei; Yang, Hao; Lu, Hong; Chen, Fa-Ming; Jin, Yan

    2013-12-01

    Cell sheet engineering is a scaffold-free delivery concept that has been shown to improve mesenchymal stem cell-mediated regeneration of injured or pathologically damaged periodontal tissues in preclinical studies and several clinical trials. However, the best strategy for cell sheet production remains to be identified. The aim of this study was to investigate the biological effects of osthole, a coumarin-like derivative extracted from Chinese herbs, on the cell sheet formation and osteogenic properties of human periodontal ligament stem cells (PDLSCs) and jaw bone marrow mesenchymal stem cells (JBMMSCs). Patient-matched PDLSCs and JBMMSCs were isolated, and an appropriate concentration of osthole for cell culture was screened for both cell types in terms of cell proliferation and alkaline phosphatase (ALP) activity. Next, the best mode of osthole stimulation for inducing the formation of sheets by each cell type was selected by evaluating the amount of their extracellular matrix (ECM) protein production as well as osteogenic-related gene expression. Furthermore, both PDLSC and JBMMSC sheets obtained from each optimized technique were transplanted subcutaneously into nude mice to evaluate their capacity for ectopic bone regeneration. The results revealed that 10(-5) m/L osthole significantly enhanced the proliferation of both PDLSCs and JBMMSCs (P osthole groups (P > 0.05). In addition, 10(-5) m/L osthole was the best concentration to promote the ALP activities of both cells (P osthole throughout the entire culture stage (10 days) for PDLSCs or at the early stage (first 3 days) for JBMMSCs was the most effective osthole administration mode for cell sheet formation (P osthole-mediated PDLSC and JBMMSC sheets formed more new bone than those obtained without osthole intervention (P osthole stimulation may enhance ECM production and positively affect cell behavior in cell sheet engineering. PMID:24095254

  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. 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.

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

    International Nuclear Information System (INIS)

    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

  5. 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.

  6. 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.

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

    International Nuclear Information System (INIS)

    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

  8. 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.

  9. 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.

  10. 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 ...

  11. 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.

  12. Donor Graft Steatosis Influences Immunity to Hepatitis C Virus and Allograft Outcome After Liver Transplantation

    Science.gov (United States)

    Subramanian, Vijay; Seetharam, Anil B; Vachharajani, Neeta; Tiriveedhi, Venkataswarup; Angaswamy, Nataraju; Ramachandran, Sabarinathan; Crippin, Jeffrey S; Shenoy, Surendra; Chapman, William C; Mohanakumar, Thalachallour; Anderson, Christopher D

    2011-01-01

    Background Hepatitis C (HCV) recurrence following orthotopic liver transplantation (OLT) is universal, often with accelerated allograft fibrosis. Donor liver steatosis is frequently encountered and often associated with poor early post-operative outcome. The study’s aim was to test the hypothesis that allograft steatosis alters immune responses to HCV and self-antigens promoting allograft fibrosis. Methods Forty-eight HCV OLT recipients (OLTr) were enrolled and classified based on amount of allograft macrovesicular steatosis at time of OLT. Group 1-No Steatosis (0–5% steatosis, n=21), Group 2 – Mild (5–35% - n=16), Group 3 – moderate (>35%, n=11). Cells secreting IL-17, IL-10, IFN-γ in response to HCV antigens were enumerated by ELISpot. Serum cytokines were measured by Luminex, antibodies (Abs) to Collagen (Col) I, II, III, IV, V by ELISA. Results OLTr of moderate steatotic grafts had the highest incidence of advanced fibrosis in protocol one-year post-OLT biopsy (10.8% vs. 15.8% vs. 36.6%, r = 0.157, pliver associated self antigens which may contribute to allograft fibrosis and poor outcome. PMID:22011763

  13. 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.

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

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    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.

  15. Pancreatic stem cells differentiation and allograft for the treatment of diabetes%胰腺干细胞诱导分化后同种移植治疗糖尿病的实验研究

    Institute of Scientific and Technical Information of China (English)

    史光军; 张磊; 许评; 栾绍海; 于江; 陈昊强

    2011-01-01

    Objective To investigate the potential of pancreatic stem cells (PSCs) directed differentiation in vitro, and to evaluate the effects of differentiated PSCs allograft on the treatment of diabetes.Methods The PSCs of adult Wistar rats were separated and purified in vitro. The surface of PSCs was determined by immunofluorescence staining, and then it was stimulated by hepatocyte growth factor (HGF) and nicotinamide to induce directed differentiation. Dithizone dyeing was used to determine the islet-like cells after induction, and ELISA staining method was used to detect the insulin levels. Streptozotocin peritoneal injection was used to induce the diabetic rat mode. 40 rats were randomly allocated into pancreatic islet cells allograft group (experiment group) and placebo group. The serum insulin and glucose levels 1 d before transplantation and 1, 2, 3, 4 week after transplantation were measured. Results PSCs of adult Wistar rats were successfully obtained, and the expression of CK19, Pdx-1 and Nestin on cell surface was positive. Dithizone dyeing for directed differentiation cells showed brownish red color. The cells could express and secrete insulin after hyperglycaemia stimulation. The serum insulin and glucose levels 4 week after transplantation were (11.41 ±1.52) mU/L and (8.22 ± 2.7) mmol/L, which were (9.30 ± 1.56) mU/L and (12.23 ± 3.8) mmol/L in the placebo group, and difference was statistically significant (P<0.05). Conclusions PSCs can be induced and directed differentiated in vitro into islet-like clusters with insulin secretion function. And its allograft has the potential for the treatment of diabetes.%目的 探讨胰腺干细胞体外定向分化潜能,评价诱导分化后细胞同种移植对糖尿病的治疗效果.方法 体外分离、纯化成体Wistar大鼠胰腺干细胞,运用荧光免疫染色法对胰腺干细胞表面进行鉴定,然后在肝细胞生长因子、尼克酰胺等共刺激下诱导细胞定向分化.双硫腙(DTZ)染

  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. Efficiently engineered cell sheet using a complex of polyethylenimine–alginate nanocomposites plus bone morphogenetic protein 2 gene to promote new bone formation

    Directory of Open Access Journals (Sweden)

    Jin H

    2014-05-01

    Full Text Available Han Jin,1 Kai Zhang,2 Chunyan Qiao,1 Anliang Yuan,1 Daowei Li,1 Liang Zhao,1 Ce Shi,1 Xiaowei Xu,1 Shilei Ni,1 Changyu Zheng,3 Xiaohua Liu,4 Bai Yang,2 Hongchen Sun11Department of Pathology, School of Stomatology, Jilin University, Changchun, People’s Republic of China; 2State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, People’s Republic of China; 3Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA; 4Department of Biomedical Sciences, Texas A&M University Baylor College of Dentistry, Dallas, TX, USAAbstract: Regeneration of large bone defects is a common clinical problem. Recently, stem cell sheet has been an emerging strategy in bone tissue engineering. To enhance the osteogenic potential of stem cell sheet, we fabricated bone morphogenetic protein 2 (BMP-2 gene-engineered cell sheet using a complex of polyethylenimine–alginate (PEI–al nanocomposites plus human BMP-2 complementary(cDNA plasmid, and studied its osteogenesis in vitro and in vivo. PEI–al nanocomposites carrying BMP-2 gene could efficiently transfect bone marrow mesenchymal stem cells. The cell sheet was made by culturing the cells in medium containing vitamin C for 10 days. Assays on the cell culture showed that the genetically engineered cells released the BMP-2 for at least 14 days. The expression of osteogenesis-related gene was increased, which demonstrated that released BMP-2 could effectively induce the cell sheet osteogenic differentiation in vitro. To further test the osteogenic potential of the cell sheet in vivo, enhanced green fluorescent protein or BMP-2-producing cell sheets were treated on the cranial bone defects. The results indicated that the BMP-2-producing cell sheet group was more efficient than other groups in promoting bone formation in the defect area. Our results suggested that PEI

  18. PD-L1 Deficiency within Islets Reduces Allograft Survival in Mice.

    Directory of Open Access Journals (Sweden)

    Dongxia Ma

    Full Text Available Islet transplantation may potentially cure type 1 diabetes mellitus (T1DM. However, immune rejection, especially that induced by the alloreactive T-cell response, remains a restraining factor for the long-term survival of grafted islets. Programmed death ligand-1 (PD-L1 is a negative costimulatory molecule. PD-L1 deficiency within the donor heart accelerates allograft rejection. Here, we investigate whether PD-L1 deficiency in donor islets reduces allograft survival time.Glucose Stimulation Assays were performed to evaluate whether PD-L1 deficiency has detrimental effects on islet function. Islets isolated from PDL1-deficient mice or wild- type (WT mice (C57BL/6j were implanted beneath the renal capsule of streptozotocin (STZ-induced diabetic BALB/c mice. Blood glucose levels and graft survival time after transplantation were monitored. Moreover, we analyzed the residual islets, infiltrating immune cells and alloreactive cells from the recipients.PD-L1 deficiency within islets does not affect islet function. However, islet PD-L1 deficiency increased allograft rejection and was associated with enhanced inflammatory cell infiltration and recipient T-cell alloreactivity.This is the first report to demonstrate that PD-L1 deficiency accelerated islet allograft rejection and regulated recipient alloimmune responses.

  19. The composition of the microbiota modulates allograft rejection.

    Science.gov (United States)

    Lei, Yuk Man; Chen, Luqiu; Wang, Ying; Stefka, Andrew T; Molinero, Luciana L; Theriault, Betty; Aquino-Michaels, Keston; Sivan, Ayelet S; Nagler, Cathryn R; Gajewski, Thomas F; Chong, Anita S; Bartman, Caroline; Alegre, Maria-Luisa

    2016-07-01

    Transplantation is the only cure for end-stage organ failure, but without immunosuppression, T cells rapidly reject allografts. While genetic disparities between donor and recipient are major determinants of the kinetics of transplant rejection, little is known about the contribution of environmental factors. Because colonized organs have worse transplant outcome than sterile organs, we tested the influence of host and donor microbiota on skin transplant rejection. Compared with untreated conventional mice, pretreatment of donors and recipients with broad-spectrum antibiotics (Abx) or use of germ-free (GF) donors and recipients resulted in prolonged survival of minor antigen-mismatched skin grafts. Increased graft survival correlated with reduced type I IFN signaling in antigen-presenting cells (APCs) and decreased priming of alloreactive T cells. Colonization of GF mice with fecal material from untreated conventional mice, but not from Abx-pretreated mice, enhanced the ability of APCs to prime alloreactive T cells and accelerated graft rejection, suggesting that alloimmunity is modulated by the composition of microbiota rather than the quantity of bacteria. Abx pretreatment of conventional mice also delayed rejection of major antigen-mismatched skin and MHC class II-mismatched cardiac allografts. This study demonstrates that Abx pretreatment prolongs graft survival, suggesting that targeting microbial constituents is a potential therapeutic strategy for enhancing graft acceptance.

  20. The composition of the microbiota modulates allograft rejection.

    Science.gov (United States)

    Lei, Yuk Man; Chen, Luqiu; Wang, Ying; Stefka, Andrew T; Molinero, Luciana L; Theriault, Betty; Aquino-Michaels, Keston; Sivan, Ayelet S; Nagler, Cathryn R; Gajewski, Thomas F; Chong, Anita S; Bartman, Caroline; Alegre, Maria-Luisa

    2016-07-01

    Transplantation is the only cure for end-stage organ failure, but without immunosuppression, T cells rapidly reject allografts. While genetic disparities between donor and recipient are major determinants of the kinetics of transplant rejection, little is known about the contribution of environmental factors. Because colonized organs have worse transplant outcome than sterile organs, we tested the influence of host and donor microbiota on skin transplant rejection. Compared with untreated conventional mice, pretreatment of donors and recipients with broad-spectrum antibiotics (Abx) or use of germ-free (GF) donors and recipients resulted in prolonged survival of minor antigen-mismatched skin grafts. Increased graft survival correlated with reduced type I IFN signaling in antigen-presenting cells (APCs) and decreased priming of alloreactive T cells. Colonization of GF mice with fecal material from untreated conventional mice, but not from Abx-pretreated mice, enhanced the ability of APCs to prime alloreactive T cells and accelerated graft rejection, suggesting that alloimmunity is modulated by the composition of microbiota rather than the quantity of bacteria. Abx pretreatment of conventional mice also delayed rejection of major antigen-mismatched skin and MHC class II-mismatched cardiac allografts. This study demonstrates that Abx pretreatment prolongs graft survival, suggesting that targeting microbial constituents is a potential therapeutic strategy for enhancing graft acceptance. PMID:27322054

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Pathological changes after bone marrow and skin allograft transplantation in rats inflicted with severe combined radiation-burn injury

    International Nuclear Information System (INIS)

    Bone marrow and skin allografts from the same donor were transplanted to rats inflicted with 8 Gy γ-radiation combined with third degree burns of 15% body surface area within 6 hr post injury. Pathological changes of hematopoietic tissues and skin allografts were studied. All injured controls died within 7 days post injury without bone marrow regeneration; 50% of treated rats survived with living skin allografts on 50th day post injury. On days 100 and 480 post operation, grafted skin still survived well on recipients with normal ultrastructure. Epidermic cells of skin allografts proliferated on day 5, developed and repaired on day 10. Histological structure of the skin returned to normal on day 30 post operation. The regeneration of bone marrow appeared on 5th day, increased markedly on day 10, and almost completed on day 15 after bone marrow transplantation. However, the regeneration of lymphocytes in cortex of spleen and lymph nodes did not appear until day 15 of BMT. The results show that bone marrow and skin allograft transplantation at early time post injury in most severe combined radiation-burn injury have tremendous beneficial effects, and the skin allograft can survive for a long time

  8. Lentivirus IL-10 gene therapy down-regulates IL-17 and attenuates mouse orthotopic lung allograft rejection.

    Science.gov (United States)

    Hirayama, S; Sato, M; Loisel-Meyer, S; Matsuda, Y; Oishi, H; Guan, Z; Saito, T; Yeung, J; Cypel, M; Hwang, D M; Medin, J A; Liu, M; Keshavjee, S

    2013-06-01

    The purpose of the study was to examine the effect of lentivirus-mediated IL-10 gene therapy to target lung allograft rejection in a mouse orthotopic left lung transplantation model. IL-10 may regulate posttransplant immunity mediated by IL-17. Lentivirus-mediated trans-airway luciferase gene transfer to the donor lung resulted in persistent luciferase activity up to 6 months posttransplant in the isograft (B6 to B6); luciferase activity decreased in minor-mismatched allograft lungs (B10 to B6) in association with moderate rejection. Fully MHC-mismatched allograft transplantation (BALB/c to B6) resulted in severe rejection and complete loss of luciferase activity. In minor-mismatched allografts, IL-10-encoding lentivirus gene therapy reduced the acute rejection score compared with the lentivirus-luciferase control at posttransplant day 28 (3.0 ± 0.6 vs. 2.0 ± 0.6 (mean ± SD); p = 0.025; n = 6/group). IL-10 gene therapy also significantly reduced gene expression of IL-17, IL-23, and retinoic acid-related orphan receptor (ROR)-γt without affecting levels of IL-12 and interferon-γ (IFN-γ). Cells expressing IL-17 were dramatically reduced in the allograft lung. In conclusion, lentivirus-mediated IL-10 gene therapy significantly reduced expression of IL-17 and other associated genes in the transplanted allograft lung and attenuated posttransplant immune responses after orthotopic lung transplantation. PMID:23601206

  9. Pretreatment of donor islets with papain improves allograft survival without systemic immunosuppression in mice.

    Science.gov (United States)

    Kumano, Kenjiro; Nishinakamura, Hitomi; Mera, Toshiyuki; Itoh, Takeshi; Takahashi, Hiroyuki; Fujiwara, Toshiyoshi; Kodama, Shohta

    2016-09-01

    Although current immunosuppression protocols improve the efficacy of clinical allogenic islet transplantation, T cell-mediated allorejection remains unresolved, and major histocompatibility complexes (MHCs) play a crucial role in this process. Papain, a cysteine protease, has the unique ability to cleave the extracellular domain of the MHC class I structure. We hypothesized that pretreatment of donor islets with papain would diminish the expression of MHC class I on islets, reducing allograft immunogenicity and contributing to prolongation of islet allograft survival. BALB/c islets pretreated with papain were transplanted into C57BL/6J mice as an acute allorejection model. Treatment with 1 mg/mL papain significantly prolonged islet allograft survival. In vitro, to determine the inhibitory effect on T cell-mediated alloreactions, we performed lymphocyte proliferation assays and mixed lymphocyte reactions. Host T cell activation against allogenic islet cells was remarkably suppressed by pretreatment of donor islet cells with 10 mg/mL papain. Flow cytometric analysis was also performed to investigate the effect of papain treatment on the expression of MHC class I on islets. One or 10 mg/mL papain treatment reduced MHC class I expression on the islet cell surface. Pretreatment of donor islets with papain suppresses MHC class I-mediated allograft rejection in mice and contributes to prolongation of islet allograft survival without administration of systemic immunosuppressants. These results suggest that pretreatment of human donor islets with papain may reduce the immunogenicity of the donor islets and minimize the dosage of systemic immunosuppressants required in a clinical setting. PMID:27618231

  10. Enhancement of bone marrow allografts from nude mice into mismatched recipients by T cells void of graft-versus-host activity.

    OpenAIRE

    Lapidot, T; Lubin, I; Terenzi, A; Faktorowich, Y; Erlich, P; Reisner, Y

    1990-01-01

    Transplantation of 8 x 10(6) C57BL/6-Nu+/Nu+ (nude) bone marrow cells into C3H/HeJ recipients after conditioning with 8 Gy of total body irradiation has resulted in a markedly higher rate of graft rejection or graft failure compared to that found in recipients of normal C57BL/6 or C57BL/6-Bg+/Bg+ (beige) T-cell-depleted bone marrow. Mixing experiments using different numbers of nude bone marrow cells with or without mature thymocytes (unagglutinated by peanut agglutinin) revealed that engraft...

  11. Chimeric Allografts Induced by Short-Term Treatment With Stem Cell Mobilizing Agents Result in Long-Term Kidney Transplant Survival Without Immunosuppression: II, Study in Miniature Swine.

    Science.gov (United States)

    Cameron, A M; Wesson, R N; Ahmadi, A R; Singer, A L; Hu, X; Okabayashi, T; Wang, Y; Shigoka, M; Fu, Y; Gao, W; Raccusen, L C; Montgomery, R A; Williams, G M; Sun, Z

    2016-07-01

    Transplantation is now lifesaving therapy for patients with end-stage organ failure but requires lifelong immunosuppression with resultant morbidity. Current immunosuppressive strategies inhibit T cell activation and prevent donor-recipient engagement. Therefore, it is not surprising that few host cells are demonstrated in donor grafts. However, our recent small animal studies found large numbers of recipient stem cells present after transplantation and pharmacological mobilization, resulting in a chimeric, repopulated organ. We now confirm these findings in a well-characterized large animal preclinical model. Here, we show that AMD3100 and FK506 mobilization of endogenous stem cells immediately post kidney transplantation combined with repeat therapy at 1, 2, and 3 months led to drug-free long-term survival in maximally immunologically mismatched swine. Three long-term recipients have stable chimeric transplants, preserved antidonor skin graft responses, and normal serum creatinine levels despite withdrawal of all medication for 3 years. PMID:26748958

  12. Cell-free cryopreserved arterial allografts from multiorgan donors: a new strategy to fabricate artificial blood vessels suited for peripheral vascular surgery

    OpenAIRE

    Papadopulos, Francesca Marzia

    2012-01-01

    Critical lower limb ischemia is a severe disease. A common approach is infrainguinal bypass. Synthetic vascular prosthesis, are good conduits in high-flow low-resistance conditions but have difficulty in their performance as small diameter vessel grafts. A new approach is the use of native decellularized vascular tissues. Cell-free vessels are expected to have improved biocompatibility when compared to synthetic and are optimal natural 3D matrix templates for driving stem cell growth and tiss...

  13. 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.

  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. 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. 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.

  18. Bone Allografts: What Is the Risk of Disease Transmission with Bone Allografts?

    Science.gov (United States)

    ... calculated to be one in 2.8 billion [Russo 1995]. Therefore, the established exclusionary criteria combined with ... bone allograft. J Periodontol 1992;12:979–983. Russo R, Scarborough N. Inactivation of viruses in demineralized ...

  19. Thermoresponsive polyurethane/siloxane membrane for wound dressing and cell sheet transplantation: In-vitro and in-vivo studies.

    Science.gov (United States)

    Rezapour-Lactoee, Alireza; Yeganeh, Hamid; Ostad, Seyed Nasser; Gharibi, Reza; Mazaheri, Zohreh; Ai, Jafar

    2016-12-01

    Polyurethane/siloxane based wound dressing for transferring fibroblast cell sheet to wounded skin and ability to provide an optimum condition for cellular activity at damaged tissue was prepared in this research. The dressing was made thermoresponsive, via the introduction of a poly(N-isopropyl acrylamide) copolymer into the backbone of dressing. The ability of membrane for adhesion, growth, and proliferation of fibroblast cells was improved via surface modification with gelatin. The optimized dressing exhibited appropriate tensile strength (4.5MPa) and elongation at break (80%) to protect wound against physical forces. Due to controlled equilibrium water absorption of about 89% and water vapor transmission rate of 2040g/m(2)day, the dressing could maintain the favorable moist environment over moderate to high exuding wounds. The grown cell sheet on dressing membrane could easily roll up from the surface just with lowering the temperature. The in vivo study of the wound dressed with cell loaded membrane confirmed the accelerated healing and production of tissue with complete re-epithelization, enhanced vascularization, and increased collagen deposition on the damaged area. PMID:27612775

  20. Continuous synthesis of graphene sheets by spray pyrolysis and their use as catalysts for fuel cells.

    Science.gov (United States)

    Zou, Biao; Wang, Xiao Xia; Huang, Xin Xin; Wang, Jian Nong

    2015-01-14

    Graphene sheets (GNS) were synthesized continuously by spray pyrolysis of iron carbonyl and pyridine. The Pt catalyst supported on GNS exhibited excellent durability for oxygen reduction reaction (ORR). The GNS, when used as a metal-free catalyst for ORR, showed performance even better than the commercial Pt/C catalyst. PMID:25421428

  1. New model for cardiomyocyte sheet transplantation using avirus-cell fusion technique

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    AIM To facilitate close contacts between transplantedcardiomyocytes and host skeletal muscle using cellfusion mediated by hemagglutinating virus of Japanenvelope (HVJ-E) and tissue maceration.METHODS: Cardiomyocytes (1.5 × 106) from fetalrats were first cultured. After proliferation, some cellswere used for fusion with adult muscle fibers usingHVJ-E. Other cells were used to create cardiomyocytesheets (area: about 3.5 cm2 including 2.1 × 106cells), which were then treated with Nile blue, separated,and transplanted between the latissimusdorsi and intercostal muscles of adult rats with fourcombinations of HVJ-E and/or NaOH maceration:G1: HVJ-E(+), NaOH(+), Cardiomyocytes(+); G2:HVJ-E(-), NaOH(+), Cardiomyocytes(+); G3: HVJ-E(+),NaOH(-), Cardiomyocytes(+); G4: HVJ-E(-), NaOH(-),Cardiomyocytes(-). At 1 and 2 wk after transplantation,the four groups were compared by detection of beatingdomains, motion images using moving target analysissoftware, action potentials, gene expression of MLC-2v and Mesp1 by reverse transcription-polymerasechain reaction, hematoxylin-eosin staining, and immunostainingfor cardiac troponin and skeletal myosin.RESULTS: In vitro cardiomyocytes were fused withskeletal muscle fibers using HVJ-E. Cardiomyocytesheets remained in the primary transplanted sites for2 wk. Although beating domains were detected inG1, G2, and G3 rats, G1 rats prevailed in the number,size, motion image amplitudes, and action potentialcompared with G2 and G3 rats. Close contacts wereonly found in G1 rats. At 1 wk after transplantation,the cardiomyocyte sheets showed adhesion at variouspoints to the myoblast layer in the latissimus dorsimuscle. At 2 wk after transplantation, close contactswere seen over a broad area. Part of the skeletalmuscle sarcoplasma seemed to project into themyocardiocyte plasma and some nuclei appeared toshare both sarcoplasmas.CONCLUSION: The present results

  2. 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.

  3. 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.

  4. 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.

  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. CD20 antigen expression by lymphoma cells in lung allograft recipients is associated with higher remission rate and superior survival: A study on heart and lung transplant recipients

    Directory of Open Access Journals (Sweden)

    Aghil Gholipour-Shoiili

    2014-01-01

    Full Text Available Post-transplant lymphoproliferative disorders (PTLD are one of the fatal complications of transplantation, and there is scarcity of data on the relevance of antigen expression by tumor cells in PTLD. In the current study, we aimed to investigate the potential effects of CD20 antigen expression by PTLD lesions developing in heart/lung transplant recipients. A comprehensive search was performed for reports indicating CD20 antigen tests in PTLD lesions developing in heart and/or lung transplant recipients. For data accumulation, we developed a standard questionnaire and data of patients presented in different published reports were entered into it. Finally, data from 26 previously published reports from different centers around the world were included in the analysis. CD20-positive PTLD lesions are significantly more likely to be of the B cell type (P = 0.006. PTLD in patients with a CD20-positive test represented relevantly shorter time from transplantation to PTLD, although it did not reach a significance level (P = 0.08. At the last follow-up, 53% patients were dead. Survival analysis showed no prognosis difference regarding CD20 test. When data were reanalyzed separately for heart and lung transplant recipients, lung recipients developing PTLD with a CD20-positive test were significantly more likely to represent remission episodes (P = 0.03, and also represented a significantly better outcome than CD20-negative PTLD patients (P = 0.04. CD20-positive PTLD lesions in heart/lung recipients are more likely of the B cell type and develop PTLD lesions earlier than their CD20-negative counterparts. Lung recipients developing CD20-positive PTLD lesions represented higher remission rates and better outcome. Further studies with prospective follow-up of patients are needed for confirming our findings.

  7. Time elapsed after transplantation influences the relationship between the number of regulatory T cells in lung allograft biopsies and subsequent acute rejection episodes

    DEFF Research Database (Denmark)

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

    2014-01-01

    scored for acute rejection according to the ISHLT criteria (A0-A4) and immunohistochemically stained with antibodies against FoxP3. Results: There was a tendency for a decrease in the number of Tregs/mm2 with time. However, the previous levels of Tregs/mm2 did not have any significant effect on future...... indicating a narrow therapeutic window for induction of tolerance by specifically targeting T-cells. The results also indirectly indicate that Tregs early after transplantation could have an impact on the long-term outcome. © 2014 Elsevier B.V....

  8. 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.

  9. 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.

  10. 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),

  11. 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)

  12. 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.

  13. Trichinella spiralis infection changes immune response in mice performed abdominal heterotopic cardiac transplantation and prolongs cardiac allograft survival time.

    Science.gov (United States)

    Deng, Gengguo; Deng, Ronghai; Yao, Jianping; Liao, Bing; Chen, Yinghua; Wu, Zhongdao; Hu, Hongxing; Zhou, Xingwang; Ma, Yi

    2016-01-01

    Allograft rejection has been an obstacle for long-term survival of patients for many years. Current strategies for transplant rejection are not as optimal as we expected, especially for long-term treatments. Trichinella spiralis, a nematode parasitized in mammalian muscle and as an invader, maintains harmonious with host in the long term by evading host immune attack. To determine whether T. spiralis infection impacts on allograft rejection, we performed mice cardiac allograft transplantation model by using BALB/c (H-2(b)) mice as donors and C57BL/6 (H-2(b)) mice orally infected with 300 muscle larvae for 28 days as recipients. Graft survival was monitored by daily palpation of the abdomen; histologic change was observed by H&E stain; and CD4(+), CD8(+), CD4(+)IFN-γ(+), and CD4(+)IL-17(+) T cells and regulatory T cells were examined with the use of flow cytometry. Serum cytokine levels were measured by Luminex. Finally, we found that mean survival time of cardiac allografts in T. spiralis group was 23.40 ± 1.99 days, while the vehicle control group was 10.60 ± 0.75 days. Furthermore, we observed alleviated histological changes in the heart allograft, decreased corresponding CD8(+) T cells, suppressed Th1 and Th17 responses, and increased regulatory T cell frequency in a murine cardiac transplantation model at day 7 post-transplantation in experimental group. These data suggest that T. spiralis infection resulted in prolonged allograft survival following murine cardiac transplantation, with suppressed Th1/Th17 responses and augmented regulatory T cells. PMID:26481486

  14. 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)

  15. 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.

  16. 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.

  17. Urinary Calprotectin and Posttransplant Renal Allograft Injury

    Science.gov (United States)

    Bistrup, Claus; Marcussen, Niels; Pagonas, Nikolaos; Seibert, Felix S.; Arndt, Robert; Zidek, Walter; Westhoff, Timm H.

    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 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 m2 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. PMID:25402277

  18. Cardiac allograft immune activation: current perspectives

    OpenAIRE

    Chang D; Kobashigawa J

    2014-01-01

    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, antibod...

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

    Science.gov (United States)

    Wang, Zhongshan; Wu, Guangsheng; Wei, Mengying; Liu, Qian; Zhou, Jian; Qin, Tian; Feng, Xiaoke; Liu, Huan; Feng, Zhihong; Zhao, Yimin

    2016-01-01

    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 reverse transfection approach, and miR-21 delivery significantly enhanced the in vitro osteogenic differentiation of hBMMSC sheets in terms of upregulating calcification-related gene expression and enhancing alkaline phosphatase production, collagen secretion, and mineralized nodule formation. The enhanced osteogenic activity of hBMMSC sheets might promisingly lead to more rapid and more robust bone regeneration for clinical use. PMID:27274237

  20. 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.

  1. Mouse kidney transplantation: models of allograft rejection.

    Science.gov (United States)

    Tse, George H; Hesketh, Emily E; Clay, Michael; Borthwick, Gary; Hughes, Jeremy; Marson, Lorna P

    2014-01-01

    Rejection of the transplanted kidney in humans is still a major cause of morbidity and mortality. The mouse model of renal transplantation closely replicates both the technical and pathological processes that occur in human renal transplantation. Although mouse models of allogeneic rejection in organs other than the kidney exist, and are more technically feasible, there is evidence that different organs elicit disparate rejection modes and dynamics, for instance the time course of rejection in cardiac and renal allograft differs significantly in certain strain combinations. This model is an attractive tool for many reasons despite its technical challenges. As inbred mouse strain haplotypes are well characterized it is possible to choose donor and recipient combinations to model acute allograft rejection by transplanting across MHC class I and II loci. Conversely by transplanting between strains with similar haplotypes a chronic process can be elicited were the allograft kidney develops interstitial fibrosis and tubular atrophy. We have modified the surgical technique to reduce operating time and improve ease of surgery, however a learning curve still needs to be overcome in order to faithfully replicate the model. This study will provide key points in the surgical procedure and aid the process of establishing this technique.

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. MicroRNA-155 may affect allograft survival by regulating the expression of suppressor of cytokine signaling 1.

    Science.gov (United States)

    Zhang, Maomao; Zhang, Qi; Liu, Fang; Yin, Li; Yu, Bo; Wu, Jian

    2011-10-01

    Immune rejection of organ transplants has life-threatening implications. It is believed that allograft rejection is initiated by the activation of lymphocytes following recognition of donor antigens, leading to generation of effector T lymphocytes, alloantibody production, and graft infiltration by alloreactive cells. There is solid evidence that miRNAs are integral for maintaining immune homeostasis and self-tolerance. A deeper understanding of the regulation of the immune response by miRNAs could define new mechanisms for manipulating graft immunity and preventing rejection. The miRNA miR-155 is of particular interest due to its known roles in regulating the expression of genes relevant to allograft rejection and the induction of immune tolerance. Indeed, miR-155 has been shown to dramatically impact both innate and adaptive immune processes, including inflammation, antigen presentation, T-cell differentiation, cytokine production, and T regulatory cell (Treg) functions. The suppressor of cytokine signaling 1 (SOCS1) is a critical regulator of immune cell function and an evolutionarily conserved target of miR-155 in breast cancer cells. We propose that suppression of miR-155 could enhance SOCS1 expression in immune cells and suppress allograft rejection. Further studies on the specific role of miR-155 in allograft rejection may lead to the identification of new targets for therapeutic intervention. PMID:21802214

  7. 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

  8. Dendritic cell and macrophage staining by monoclonal antibodies in tissue sections and epidermal sheets.

    OpenAIRE

    Flotte, T. J.; Springer, T A; Thorbecke, G. J.

    1983-01-01

    Mouse tissue sections were stained by monoclonal antibodies to macrophage antigens (Mac-1 (M1/70), Mac-2 (M3/38), Mac-3 (M3/84) with the use of immunoperoxidase. Mac-1 was located diffusely in the cytoplasm of round cells in a high percentage of alveolar macrophages, resident peritoneal and bone marrow cells, in splenic red pulp, and in rare perivascular cells in the thymus. Mac-1 was absent in epithelial cells and Langerhans cells. Mac-2 was strongly positive in many dendritic cells in the t...

  9. 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

  10. 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.

  11. Temporal profile of calcineurin phosphatase activity during acute allograft rejection in the heterotopic rat heart transplantation model

    DEFF Research Database (Denmark)

    Karamperis, N; Koefoed-Nielsen, P B; Marcussen, N;

    2008-01-01

    BACKGROUND: Regardless of the extensive worldwide use of calcineurin inhibitors, little is known about the behavior of calcineurin phosphatase (CaN) during acute allograft rejection. The aim of this study was to investigate the temporal profile of CaN during acute allograft rejection and reveal...... postoperative time points. CaN activity was measured in isolated peripheral blood and spleen mononuclear cells and in graft heart homogenates. CaN activity was measured as the release of radiolabeled phosphate from a previously phosphorylated 19 amino acid peptide. RESULTS: We have shown that CaN's activity...

  12. MORPHOLOGICAL AND IMMUNOHISTOCHEMICAL MANIFESTATIONS OF DIFFERENT VARIANTS OF ACUTE KIDNEY ALLOGRAFT REJECTION

    Directory of Open Access Journals (Sweden)

    A.V Trailin

    2009-01-01

    Full Text Available The aim of this study was morphological characteristics of peculiar properties of acute T-cells- (ATMR and antibody-mediated kidney allograft rejection (AAMR. Histological slices of kidney allograft biopsies were examined after coloration by routine methods and immunohistochemical proceeding for C4d, CD45R0 T-lymphocytes antigen and CD68 macrophages antigen. We’ve determined that the key features of ATMR are: increasing of T-lymphocytes interstitial infi ltration with the same level of macrophages infi ltration comparing with implantation biopsies, mild mononuclear glomerulitis and capillaritis; tubulitis. Morphological traits of AAMR are neutrophilic and T-lymphocytes glomerulitis, diffuse capillaritis, capillaries dilatation and margination of mononuclear cells with admixture of neutrophils, macrophagal interstitial infi ltration under semiquantitative evaluation, as well as, more pronounced, than in ATMR, T-lymphoctes and macrophages interstitial infi ltration under quantitative evaluation.

  13. Blockade of both B7-H4 and CTLA-4 co-signaling pathways enhances mouse islet allograft survival

    Science.gov (United States)

    Wang, Xiaojie; Hao, Jianqiang; Metzger, Daniel L.; Mui, Alice; Lee, I-Fang; Akhoundsadegh, Noushin; Chen, C. Lieping; Ou, Dawei; Ao, Ziliang; Verchere, C. Bruce; Warnock, Garth L.

    2012-01-01

    Costimulation blockade is an effective way to prevent allograft rejection. In this study, we tested the efficacy of two negative co-signaling molecules in protecting islet allograft function. We used local expression of B7-H4 by adenoviral transduction of islets (Ad-B7-H4) and systemic administration of CTLA-4.Ig to investigate the outcomes of allograft survival. Five groups of streptozotocin-induced diabetic C57BL/6 mice received 400 islets each from BALB/c donors. The groups consisted of control (G1); CTLA-4.Ig (G2); Ad-LacZ (G3); Ad-B7-H4 (G4); and Ad-B7-H4 and CTLA-4.Ig combined (G5). G1 and G3 developed graft failure on average of two weeks. G2, G4 and G5 survived for 43.8 ± 34.8, 54.7 ± 31.2 and 77.8 ± 21.5 d, respectively. Activated T and B cells in the lymph nodes were significantly controlled by CTLA-4.Ig treatment. Significantly reduced infiltrates were also detected in the allografts of G2 compared with G1. By contrast, B7-H4 significantly inhibited Th1-associated IFN-gamma secretion in the early stage and increased Foxp3+ T cells in the long-term surviving allografts. Our study suggests that CTLA-4 and B7-H4 inhibit alloimmune responses through distinct mechanisms, and that combination therapy which activates two negative co-signaling pathways can further enhance islet allograft survival. PMID:22878670

  14. 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

  15. 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...

  16. 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.

  17. 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.

  18. Determinants of long-term renal allograft outcome

    NARCIS (Netherlands)

    Leeuwen-Artz, M.A.

    2005-01-01

    Long-term renal allograft survival is markedly affected by premature death with a functioning graft, chronic allograft nephropathy, and recurrence of the original kidney disease. To improve long-term graft survival, focus is shifting from the prevention of acute rejections to the recognition and tre

  19. 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

  20. Surgical techniques and radiological findings of meniscus allograft transplantation.

    Science.gov (United States)

    Lee, Hoseok; Lee, Sang Yub; Na, Young Gon; Kim, Sung Kwan; Yi, Jae Hyuck; Lim, Jae Kwang; Lee, So Mi

    2016-08-01

    Meniscus allograft transplantation has been performed over the past 25 years to relieve knee pain and improve knee function in patients with an irreparable meniscus injury. The efficacy and safety of meniscus allograft transplantation have been established in numerous experimental and clinical researches. However, there is a lack of reviews to aid radiologists who are routinely interpreting images and evaluating the outcome of the procedures, and also meniscus allograft transplantation is not widely performed in most hospitals. This review focuses on the indications of the procedure, the different surgical techniques used for meniscus allograft transplantation according to the involvement of the lateral and medial meniscus, and the associated procedures. The postoperative radiological findings and surgical complications of the meniscus allograft transplantation are also described in detail. PMID:27423673

  1. 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.

  2. 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.

  3. 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

  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. Complications of massive allograft reconstruction for bone tumors

    Directory of Open Access Journals (Sweden)

    Abolhasan Borjian

    2006-11-01

    Full Text Available BACKGROUND: Since the evolution of multi-drug chemotherapy and radiotherapy and new sophisticated surgical techniques, limb salvage and reconstruction, rather than amputation, has become the preferred treatment for patients with bone tumors. One option is allograft replacement. Although allograft has several advantages, it is not without complications. This study was performed to observe these complications in a group of patients treated with allograft replacement for bone tumor resection. The purpose was to gain an overview of the factors predisposing to these complications to minimize their occurrence. METHODS: This retrospective study was performed on patients with benign aggressive and malignant bone tumors undergoing limb reconstruction with allograft between 1997 and 2005 in Al-Zahra and Kashani Hospitals in Isfahan, Iran. Data was collected from patient files, clinical notes, radiographs and a recent physical examination. Complications including local recurrence, fracture of allograft, fixation failure, nonunion, infection, skin necrosis and neurological damage were recorded. RESULTS: Sixty patients including 39 males and 21 females were studied. The mean age of patients was 23 ± 11.7 years. The mean follow-up interval was 28.1 ± 12.4 months (mean ± SD. Complications were allograft fracture in 20%, local recurrence in 16%, fixation failure in 11%, nonunion in 6%, infection in 6%, skin necrosis in 6%, and peroneal nerve palsy in 1% of cases. Most local recurrences (60% were those with a mal-performed biopsy. Most allograft fractures occurred when a short plate was used. CONCLUSIONS: Allograft replacement for bone tumors remains a valid option. To avoid complications, biopsy should be done by a trained surgeon in bone oncology. A long plate is recommended for fixation. Sterility and graft processing must be optimal. Autogenous bone graft must be added at host-allograft junction. KEY WORDS: Bone tumors, bone allograft, limb

  6. 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.

  7. Electron beam induced grafting of N-isopropylacrylamide to a poly(ethylene-terephthalate) membrane for rapid cell sheet detachment

    International Nuclear Information System (INIS)

    Intact sheets of human prostate epithelium cells were successfully detached from a poly(N-isopropylacrylamide) (pNIPAM) membrane radiolytically grafted to poly(ethlylene-terephthalate (PET) culture dishes. The detachment process took less than 20 min without damaging the sheet structure. The grafting was performed using a high-energy electron beam to covalently bond NIPAM to the surface of PET culture dishes. This work demonstrates that the optimal conditions for uniform grafting can be achieved by adding argon-saturated solutions of NIPAM monomer onto pre-irradiated, surface-activated PET membranes. The solutions and the membranes were then irradiated under anaerobic conditions to a total absorbed dose of 25 kGy. This grafting method involves producing carbon-centered free radicals NIPAM· and PET· from both NIPAM and PET, respectively. An investigation of the kinetics of the early stages of polymerization of NIPAM was performed through electron beam pulse radiolysis with optical detection. The pulse radiolysis experiments of anaerobic NIPAM methanol solutions show that the esol·- reacts very rapidly with NIPAM producing NIPAM·- anions with a reaction rate constant of 1.4x109±10% L mol-1 s-1. The NIPAM·- anions then undergo a protonation reaction producing the initiation free radical (NIPAM·) with a reaction rate constant of 9x102 L mol-1 s-1. Along with pulse radiolysis, electron paramagnetic resonance (EPR) measurements show that the radiolytically produced carbon-centered free radicals of the PET, PET·, decay following an overall observed pseudo-first-order reaction with rate constants of k=2.0x10-4 and 7.0x10-4 s-1 produced in argon and in air, respectively. The overall observed decay reaction involve PET·+PET· cross-linking, PET·+O2, PET+HO2·, and PET+H-atoms, since these EPR measurements were conducted under aerobic conditions.

  8. Graft vasculopathy in the skin of a human hand allograft: implications for diagnosis of rejection of vascularized composite allografts.

    Science.gov (United States)

    Kanitakis, Jean; Karayannopoulou, Georgia; Lanzetta, Marco; Petruzzo, Palmina

    2014-11-01

    Whereas vascularized composite allografts often undergo acute rejections early in the postgraft period, rejection manifesting with severe vascular changes (graft vasculopathy) has only been observed on three occasions in humans. We report a hand-allografted patient who developed severe rejection following discontinuation of the immunosuppressive treatment. It manifested clinically with erythematous maculopapules on the skin and pathologically with graft vasculopathy that affected both large vessels and smaller cutaneous ones. The observation that graft vasculopathy can affect skin vessels shows that it is amenable to diagnosis with usual skin biopsy as recommended for the follow-up of these allografts. Graft vasculopathy developing in the setting of vascularized composite allografts likely represents chronic rejection due to under-immunosuppression and, if confirmed, should be included in a future update of the Banff classification of vascularized composite allograft rejection. PMID:25041139

  9. Long-term survival of intestinal allografts induced by costimulation blockade, busulfan and donor bone marrow infusion.

    Science.gov (United States)

    Guo, Zhong; Wang, Jun; Dong, Ying; Adams, Andrew B; Shirasugi, Nozomu; Kim, Oliver; Hart, John; Newton-West, Marvin; Pearson, Thomas C; Larsen, Christian P; Newell, Kenneth A

    2003-09-01

    Tolerance-inducing strategies that infuse donor bone marrow cells in conjunction with costimulation blockade have not been applied to intestinal transplantation. Intestines from BALB/c mice were transplanted into C57BL/6 recipients treated with anti-CD40L mAb, CTLA4-Ig, donor bone marrow, and busulfan. The majority of mice transplanted after completion of this regimen developed hematopoietic macrochimerism, although the degree of chimerism varied widely between recipients, and experienced long-term allograft survival. T cells from these mice demonstrated donor-specific hyporesponsiveness in vitro. However, T cells from chimeric mice proliferated to donor alloantigen in vivo. Furthermore, chimeric mice bearing intestinal allografts were capable of rejecting subsequently placed donor-strain skin grafts. These data suggest that although long-term allograft survival occurs in the absence of acute or chronic rejection, recipient mice are not completely unresponsive to donor alloantigens. When intestinal transplantation was performed at the time of initial bone marrow infusion (initiation of the chimerism protocol), most recipients failed to develop chimerism and promptly rejected the intestinal allograft. Although this is the most effective protocol that we have tested using this stringent model of transplantation, our observations suggest that modifications will be necessary before it can be reliably applied to the transplantation of highly immunogeneic organs like the intestine. PMID:12919088

  10. 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) ).

  11. [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.

  12. 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

  13. 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.

  14. Allogeneic Transplantation of Periodontal Ligament-Derived Multipotent Mesenchymal Stromal Cell Sheets in Canine Critical-Size Supra-Alveolar Periodontal Defect Model.

    Science.gov (United States)

    Tsumanuma, Yuka; Iwata, Takanori; Kinoshita, Atsuhiro; Washio, Kaoru; Yoshida, Toshiyuki; Yamada, Azusa; Takagi, Ryo; Yamato, Masayuki; Okano, Teruo; Izumi, Yuichi

    2016-01-01

    Periodontitis is a chronic inflammatory disease that induces the destruction of tooth-supporting tissues, followed by tooth loss. Although several approaches have been applied to periodontal regeneration, complete periodontal regeneration has not been accomplished. Tissue engineering using a combination of cells and scaffolds is considered to be a viable alternative strategy. We have shown that autologous transplantation of periodontal ligament-derived multipotent mesenchymal stromal cell (PDL-MSC) sheets regenerates periodontal tissue in canine models. However, the indications for autologous cell transplantation in clinical situations are limited. Therefore, this study evaluated the safety and efficacy of allogeneic transplantation of PDL-MSC sheets using a canine horizontal periodontal defect model. Canine PDL-MSCs were labeled with enhanced green fluorescent protein (EGFP) and were cultured on temperature-responsive dishes. Three-layered cell sheets were transplanted around denuded root surfaces either autologously or allogeneically. A mixture of β-tricalcium phosphate and collagen gel was placed on the bone defects. Eight weeks after transplantation, dogs were euthanized and subjected to microcomputed tomography and histological analyses. RNA and DNA were extracted from the paraffin sections to verify the presence of EGFP at the transplantation site. Inflammatory markers from peripheral blood sera were quantified using an enzyme-linked immunosorbent assay. Periodontal regeneration was observed in both the autologous and the allogeneic transplantation groups. The allogeneic transplantation group showed particularly significant regeneration of newly formed cementum, which is critical for the periodontal regeneration. Serum levels of inflammatory markers from peripheral blood sera showed little difference between the autologous and allogeneic groups. EGFP amplicons were detectable in the paraffin sections of the allogeneic group. These results suggest that

  15. High Efficiency CdTe Ink-Based Solar Cells Using Nanocrystals (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2015-01-01

    This NREL Highlight is being developed for the 2015 February Alliance S&T Board meeting and describes a solution-processable ink to produce high-efficiency solar cells using low temperature and simple processing.

  16. Minimizing the risk of chronic allograft nephropathy.

    Science.gov (United States)

    Weir, Matthew R; Wali, Ravinder K

    2009-04-27

    Chronic allograft nephropathy, now defined as interstital fibrosis and tubular atrophy not otherwise specified, is a near universal finding in transplant kidney biopsies by the end of the first decade posttransplantation. After excluding death with functioning graft, caused by cardiovascular disease or malignancy, chronic allograft nephropathy is the leading cause of graft failure. Original assumptions were that this was not a modifiable process but inexorable, likely due to past kidney injuries. However, newer understandings suggest that acute or subacute processes are involved, and with proper diagnosis, appropriate interventions can be instituted. Our method involved a review of the primary and secondary prevention trials in calcineurin inhibitor withdrawal. Some of the more important causes of progressive graft deterioration include subclinical cellular or humoral rejection, and chronic calcineurin inhibitor toxicity. Early graft biopsy, assessment of histology, and changes in immunosuppression may be some of the most important measures available to protect graft function. The avoidance of clinical inertia in pursuing subtle changes in graft function is critical. Modification in maintenance immunosuppression may benefit many patients with early evidence of graft deterioration. PMID:19384181

  17. Forces generated by cell intercalation tow epidermal sheets in mammalian tissue morphogenesis.

    Science.gov (United States)

    Heller, Evan; Kumar, K Vijay; Grill, Stephan W; Fuchs, Elaine

    2014-03-31

    While gastrulation movements offer mechanistic paradigms for how collective cellular movements shape developing embryos, far less is known about coordinated cellular movements that occur later in development. Studying eyelid closure, we explore a case where an epithelium locally reshapes, expands, and moves over another epithelium. Live imaging, gene targeting, and cell-cycle inhibitors reveal that closure does not require overlying periderm, proliferation, or supracellular actin cable assembly. Laser ablation and quantitative analyses of tissue deformations further distinguish the mechanism from wound repair and dorsal closure. Rather, cell intercalations parallel to the tissue front locally compress it perpendicularly, pulling the surrounding epidermis along the closure axis. Functional analyses in vivo show that the mechanism requires localized myosin-IIA- and α5β1 integrin/fibronectin-mediated migration and E-cadherin downregulation likely stimulated by Wnt signaling. These studies uncover a mode of epithelial closure in which forces generated by cell intercalation are leveraged to tow the surrounding tissue. PMID:24697897

  18. Van der Waals epitaxy of ultrathin α-MoO3 sheets on mica substrate with single-unit-cell thickness

    Science.gov (United States)

    Wang, Di; Li, Jing-Ning; Zhou, Yu; Xu, Di-Hu; Xiong, Xiang; Peng, Ru-Wen; Wang, Mu

    2016-02-01

    We report on van der Waals epitaxy of single-crystalline α-MoO3 sheets with single-unit-cell thickness on the mica substrate. The crystalline lattice structure, growth habits, and Raman spectra of the grown α-MoO3 sheets are analyzed. The anisotropic growth of α-MoO3 sheets can be understood by period bond chains theory. Unlike monolayer MoS2 or graphene, Raman spectra of α-MoO3 do not possess frequency shift from bulk crystal to single-unit-cell layer. The relative intensities of two Raman modes (Ag) at 159 and 818 cm-1 are sensitive to the polarization of incident light. This scenario provides a quick approach to determine the lattice orientation of α-MoO3 crystals. Our studies indicate that van der Waals epitaxial growth is a simple and effective way to fabricate high-quality ultrathin α-MoO3 sheets for physical property investigations and potential applications.

  19. 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

  20. 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.

  1. Effect of α-GalCer-activated natural killer T cell on survival of allograft with high-risk rejection after retrobubar injection%α-GalCer活化的自然杀伤T细胞对高危角膜移植后排斥反应的防治作用

    Institute of Scientific and Technical Information of China (English)

    宫妍; 宋丽艳; 孙海成

    2012-01-01

    活时间,为角膜移植排斥反应的防治提供了新的手段.%Background Corneal graft reject is a major cause of corneal transplantation failure.Although many immune-suppressing drugs have been utilized to reduce the reject response,their adverse effects on organ and tissue are still insoluble.The tolerance induction of natural killer T (NKT) cells is currently under investigation.However,the study on the application of NKT cells in high risk corneal transplantation is seldom. Objective The present study was to explore the effects of α-GalCer-activated NKT cella on allografts survival after high-risk corneal transplantation surgery via retro-bubar injection. Methods The lymphocytes were picked up from the spleen of SPF Lewis rats and cultured in RPMI 1640 medium with 100 mg/L α-GalCer.After one week,NKT cells were sorted by the FACSVantage system as CD161+ TCR-α+ cell from the lymphocytes with the cell densities 5×106/ml.Ten SPF Fisher344 rats were used to prepare the donor corneas,and 20 Lewis rats served as recipients.The high risk corneal transplantation models were created by corneal suturing in 20 recipient rats.Penetrating keratoplasty (PKP) was performed in the model rats.0.1 ml NKT cells or the same volume of normal saline solution were retro-bubarly injected at the end of surgery respectively.The corneal allografts were observed and scored based on Holland criteria at the three-day interval under the slit lamp for 30 days.Two weeks after surgery,three rats from each group were sacrificed by excessive anesthesia method and the eyeballs were obtained for histopathological examination.The inflammatory cell infiltration ( CD4+ and CD8+ ) in grafts was evaluated by immunochemistry and flow cytometry.The use of the animals complied with the Statement of ARVO. Results The mean survival time of the allografts was (7.90± 1.37) days in normal saline solution group and (14.70± 1.49) days in NKT cell group,showing a statistically significant difference

  2. Forces Generated by Cell Intercalation Tow Epidermal Sheets in Mammalian Tissue Morphogenesis

    OpenAIRE

    Heller, Evan; Kumar, K. Vijay; Grill, Stephan W.; Fuchs, Elaine

    2014-01-01

    While gastrulation movements offer mechanistic paradigms for how collective cellular movements shape developing embryos, far less is known about coordinated cellular movements that occur later in development. Studying eyelid closure, we explore a case where an epithelium locally reshapes, expands, and moves over another epithelium. Live imaging, gene targeting and cell cycle inhibitors reveal that closure does not require overlying periderm, proliferation or supracellular actin cable assembly...

  3. 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.

  4. 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

    2016-09-01

    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

  5. 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

  6. New approaches to the management of acute and chronic cardiac allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    Isobe, Mitsuaki; Suzuki, Jun-ichi [Shinshu Univ., Matsumoto, Nagano (Japan). School of Medicine

    1998-05-01

    There are still many problems to be faced in the field of heart transplantation. Acute and chronic rejection are still the major medical obstacles. In this review, we describe recent research in this field undertaken in our laboratory. The induced intercellular adhesion molecule-1 (ICAM-1) and MHC class II antigen resulting from rejection can be visualized in vivo by radioimmunoscintigraphy. This non-invasive method is sensitive for detecting early rejection and allows quantitative assessment of rejection. Short-term administration of monoclonal antibodies to ICAM-1 and leukocyte function-associated antigen-1 (LFA-1) results in an indefinite acceptance of cardiac allografts by induction of antigen-specific tolerance, as evidenced by acceptance of the secondary skin allografts. The characteristics and possible mechanisms of this tolerance induction are discussed. Immunohistopathologic features of graft coronary arteriopathy are shown. Adhesion molecules, cytokines, and growth factors are associated with intimal hyperplasia and phenotypic transformation of smooth muscle cells in the allograft coronary arteries. Dramatic reduction in this intimal hyperplasia was demonstrated by antisense gene therapy targeting cyclin-dependent kinase 2 kinase. We hope that these investigations will contribute to the improvement of the management of patients who undergo heart transplantation. (author). 117 refs.

  7. 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%The protective effects on the renal allografts from brain dead donor rats pretreated with bone marrow mesenchymal stem cells

    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

    目的 探讨骨髓间充质干细胞(MSC)预处理脑死亡(BD)供鼠对移植肾的保护作用.方法 实验分正常移植组、脑死亡供肾移植组(BD移植组)和输注MSC+脑死亡供肾移植组(MSC处理组),雄性F344大鼠为供者,雄性Lewis大鼠为受者,正常移植组为常规移植;BD移植组为脑死亡F344大鼠供肾;MSC处理组在移植前输注预先制备的来自F344大鼠的MSC,然后接受脑死亡F344大鼠供肾移植.移植后给予环孢素A,连用10天.术后第10天切除其右肾.测定术后第14、21、28和35天血肌酐水平.术后35 d获取移植肾标本,行病理学观察;免疫组化检测移植肾组织中白细胞介素(IL)-1β和肿瘤坏死因子α(TNF-α)表达情况.结果 BD移植组术后各检测时点的血肌酐水平均高于其余两组(P<0.05),而MSC处理组和正常移植组间除第21天的血清肌酐值外,其余时间段的差异没有统计学意义.BD移植组移植肾组织中可见单核细胞浸润,其肾小管上皮炎症明显重于其他两组,MSC处理组与正常移植组的差异不大.BD移植组移植肾肾小球上皮细胞、肾小管上皮细胞、间质细胞的IL-1β和TNF-α的表达均呈阳性,染色程度较强,明显强于其他两组(H=7.210,P=0.027),而MSC处理组和正常移植组间的差异无统计学意义.结论MSC预处理脑死亡供鼠,可能通过减少移植肾炎症细胞浸润,降低TNF-α和IL-1β表达来减轻移植肾损伤.%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

  8. 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

  9. Renalase Gene Polymorphism in Patients After Renal Allograft Transplantation

    Directory of Open Access Journals (Sweden)

    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.

  10. 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.

  11. Osteochondral Allograft Transplantation in the Knee.

    Science.gov (United States)

    Zouzias, Ioannis C; Bugbee, William D

    2016-06-01

    The technique of osteochondral allograft (OCA) transplantation has been used to treat a wide spectrum of cartilage deficiencies in the knee. Its use has been supported by basic science and clinical studies that show it is a safe and effective treatment option. What sets fresh OCA transplantation apart from other cartilage procedures in the knee, is the ability to treat large defects with mature hyaline cartilage. Studies looking at transplantation of fresh OCAs in the general population have shown reliable pain relief and return to activities of daily living. Reports of cartilage injuries in athletes have risen over the years and more research is needed in evaluating the successfulness of OCA transplantation in the athletic population. PMID:27135291

  12. 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

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

    Directory of Open Access Journals (Sweden)

    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. 

  14. Leukocytic acetylcholine in chronic rejection of renal allografts

    OpenAIRE

    Wilczynska, Joanna

    2011-01-01

    Leukocytes, which accumulate in graft blood vessels during fatal acute rejection of experimental renal allografts, synthesise and release acetylcholine (ACh). In this study, I tested the hypothesis that ACh produced by leukocytes accumulating in graft blood vessels contributes to the pathogenesis of chronic renal allograft vasculopathy (CAV). Kidneys were transplanted in the allogeneic Fischer 344 to Lewis rat strain combination. Isogeneic transplantations were performed in Lew...

  15. Nox-2 Is a Modulator of Fibrogenesis in Kidney Allografts

    OpenAIRE

    Djamali, A; A Vidyasagar; Adulla, M.; Hullett, D.; Reese, S.

    2008-01-01

    We studied the role of classical phagocytic NADPH oxidase (Nox) in the pathogenesis of kidney allograft tubulointerstitial fibrosis. Immunofluorescence studies showed that Nox-2 and p22phox (electron transfer subunits of Nox) colocalized in the tubulointerstitium of human kidney allografts. Tubular Nox-2 also colocalized with α -SMA in areas of injury, suggestive of epithelial-to-mesenchymal transition (EMT). Interstitial macrophages (CD68+) and myofibroblasts (α -SMA+) expressed Nox-2 while ...

  16. Deceased donor skin allograft banking: Response and utilization

    Directory of Open Access Journals (Sweden)

    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.

  17. De Novo Collapsing Glomerulopathy in a Renal Allograft Recipient

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  19. Adoptive transfer of mix-cultured hone marrow cells to prolong survival of cardiac allografts in mice%混合培养的供、受者骨髓细胞过继回输延长小鼠移植心脏存活时间

    Institute of Scientific and Technical Information of China (English)

    王慧; 刘世雄; 杨能; 周佩军; 邵琨; 赵菊平; 徐达; 王祥慧; 沈周俊; 路丽明

    2009-01-01

    目的 将供、受者骨髓细胞经混合培养后过继回输,以观察其对同种异体移植心脏存活时间和受者免疫功能的影响.方法 取Balb/c小鼠和C57BL/6J小鼠的骨髓细胞,进行混合培养.配制含Balb/c小鼠和C57BL/6J小鼠脾淋巴细胞的混合淋巴细胞反应体系(MLR)以及含Balb/c小鼠和C3H小鼠脾淋巴细胞的MLR,分别加入混合培养的骨髓细胞,观察其对MLR中细胞增殖的影响.以C57BL/6J小鼠为供者,Balb/c小鼠为受者行腹腔异位心脏移植,实验分为4组:(1)移植对照组,受者仅进行心脏移植,不作其他处理;(2)实验对照组,心脏移植后给予西罗莫司灌胃;(3)实验组,移植手术结束前注射混合培养的骨髓细胞1×10~7个,术后给予西罗莫司;(4)第三方对照组,受者接受C3H小鼠的移植心脏,手术结束前注射混合培养的骨髓细胞1×10~7个,术后给予西罗莫司.记录移植心脏存活时间;移植心脏停跳当日,取受者外周血,检测CD4~+ CD25~+ T淋巴细胞的比例及供者来源的H-2K~b细胞的比例.结果 加入混合培养的骨髓细胞后,Balb/c和C57BL/6J的MLR的淋巴细胞增殖率低于Balb/c和C3H的MLR.实验组移植心脏的存活时间长于其他3组(P<0.05).实验组CD4~+CD25~+T淋巴细胞的百分率高于其他3组(P<0.05).实验组外周血中H-2K~b细胞的比例高于其他3组(P<0.05).结论 受者输注混合培养的供、受者骨髓细胞可在一定程度上调节免疫应答,延长小鼠移植心脏的存活时间,该作用具有供者抗原特异性.%Objective To investigate the effects of adoptive transfer of mix-cultured bone marrow cells (BMC) from donor and recipient on allograft and immune system after the recipients preconditioned by a non-myeloablative regimen.Methods Mix-cultured BMC were added into mixed lymphocyte reaction.The effects of mix-cultured BMC on lymphocyte proliferation and their specificity were observed.Heart from C57BL/6 mouse was transplanted into Balb

  20. 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.

  1. Musculoskeletal allograft risks and recalls in the United States.

    Science.gov (United States)

    Mroz, Thomas E; Joyce, Michael J; Steinmetz, Michael P; Lieberman, Isador H; Wang, Jeffrey C

    2008-10-01

    There have been several improvements to the US tissue banking industry over the past decade. Tissue banks had limited active government regulation until 1993, at which time the US Food and Drug Administration began regulatory oversight because of reports of disease transmission from allograft tissues. Reports in recent years of disease transmission associated with the use of allografts have further raised concerns about the safety of such implants. A retrospective review of allograft recall data was performed to analyze allograft recall by tissue type, reason, and year during the period from January 1994 to June 30, 2007. During the study period, more than 96.5% of all allograft tissues recalled were musculoskeletal. The reasons underlying recent musculoskeletal tissue recalls include insufficient or improper donor evaluation, contamination, recipient infection, and positive serologic tests. Infectious disease transmission following allograft implantation may occur if potential donors are not adequately evaluated or screened serologically during the prerecovery phase and if the implant is not sterilized before implantation. PMID:18832599

  2. Prevention of the induction of allospecific cytotoxic T lymphocyte and delayed-type hypersensitivity responses by ultraviolet irradiation of corneal allografts

    International Nuclear Information System (INIS)

    The effect of ultraviolet radiation (UVR) on the immunogenicity of corneal allografts was examined in a mouse model. Corneal allografts differing from the host at the entire MHC and multiple minor H loci were subjected to 200 mJ/cm2 of UVB irradiation immediately prior to heterotropic transplantation. Analysis of cytotoxic T lymphocyte and delayed-type hypersensitivity responses revealed that UVR treated corneal grafts failed to induce either CTL or DTH responses in C57BL/6 recipients. UVB treatment abolished the immunogenicity of highly immunogenic corneal grafts containing either resident or infiltrating donor-specific Langerhans cells. Sequential grafting experiments demonstrated that UVB-treated grafts rendered the hosts anergic to subsequent immunization with highly immunogenic corneal limbus grafts that contained dense concentrations of Ia+ Langerhans cells of donor origin. The results indicate that UV treatment not only reduces the immunogenicity of the corneal allograft but may also render it tolerogenic

  3. Reduced CD40L expression on ex vivo activated CD4+T-lymphocytes from patients with excellent renal allograft function measured with a rapid whole blood flow cytometry procedure

    OpenAIRE

    Lederer, Stephan R.; Friedrich, N; Gruber, R; Landgraf, R; Toepfer, Marcel; Sitter, Thomas

    2004-01-01

    Background: The CD40-CD40L (CD154) costimulatory pathway plays a critical role in the pathogenesis of kidney allograft rejection. In renal transplant biopsies, CD4+ CD40L+ graft-infiltrating cells were detected during chronic rejection in contrast to acute rejection episodes. Using a rapid noninvasive FACS procedure, we were able to demonstrate CD40L upregulation in peripheral blood of patients with chronic renal allograft dysfunction. Materials and Methods: Whole blood from recipients of ren...

  4. 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.

  5. 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. PMID:24414293

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Interleukin-1 receptor antagonist eye drops promoting high-risk corneal allografts survival in rats

    Institute of Scientific and Technical Information of China (English)

    接英; 张文华; 潘志强; 武宇影; 王颖

    2004-01-01

    Background Immune rejection is the main reason of grafts failure after corneal transplantation. This study was to determine whether interlerkin-1 receptor antagonist (IL-1ra) eye drops could prolong corneal allografts survival in high-risk corneal orthotopic allotransplantation in rat model and to study the effect of IL-1ra on the expression of CD1-positive cells in the grafts. Methods For all experiments, the Sprague-Dawley (SD) rats' corneas were transplanted into Wistar rats' eyes. High-risk transplants included those that had been sutured into Wistar recipient beds with corneal neovascularization induced by placement of three interrupted sutures in the host cornea 7 days earlier. All the animals were divided, in a masked fashion, into three treatment groups and one control group. Each treatment group received IL-1ra eye drops of different concentrations (1 mg/ml, 3 mg/ml, or 5 mg/ml, respectively) four times a day for 30 days. The control group received 0.9% normal saline (NS) eye drops in the same way as the treatment groups. All allografts were evaluated for signs of rejection from the first day after surgery. Ten days later, corneal specimens were processed to examine the expression of CD1-positive cells and histopathological changes. Results The survival time of the transplants was 5.80±0.79, 5.89±1.05, 6.78±0.83, and 9.00±2.36 days respectively in the control or three treatment groups. Compared with the control group, 1 mg/ml IL-1ra eye drop did not prolong the survival time of the allografts (t=0.210, P>0.05). However, 3 mg/ml and 5 mg/ml IL-1ra eye drop did prolong the survival time of the grafts (t≥2.627, P<0.05), with the latter showing more obvious effect. Immunohistochemical examinations showed a significant decrease in inflammatory cell and CD1-positive cell infiltration in IL-1ra treated groups compared with the control group. Conclusions IL-1ra can promote corneal allograft survival in a dose-dependant manner by reducing the infiltration of

  11. RNA干扰沉默骨桥蛋白对大鼠移植肾小管上皮细胞向间充质转分化的作用%Effect of silencing osteopontin by RNA interference upon EMT of tubular epithelial cells in rats with chronic allograft nephropathy

    Institute of Scientific and Technical Information of China (English)

    张挺; 徐东亮; 周强平; 鲁佩; 殷长军; 张炜; 徐正铨; 顾民

    2011-01-01

    Objective:To investigate the effect of in vivo shRNA plasmid vector gene transfer to silence OPN expression upon epithelial to mesenchymal transition of the tubular epithelial cells (TECs) in rat chronic allograft nephropathy (CAN) models, and to explore the possible role of OPN in CAN. Methods: Orthotopic renal-transplantation using F344 rats as donors and Lewis rats as recipients was operated to establish Allo group, while transplantation from Lewis to Lewis rats as Syn group. Hydromechanics based gene transfer method was used to establish RNAi and EV groups, for which OPN-shRNA or empty vector was injected into the renal vein. Rats in each group were sacrificed 12 weeks after the surgery. Allograft samples were collected and sectioned for HE staining, masson's trichrome staining, immunohislochemical study and Western blot assay. Results: The morphological changes of allograft in Allo/EV group consist with CAN. Compared with the Syn group,Western blot showed a significant rise of OPN expression. In the RNAi group, the OPN expression was significantly reduced(P<0.05) compared with Allo/EV group. The RNA interference inhibited EMT of TECs and the pathogenesis of CAN, which were confirmed by immunohistochemistry and HE/Masson's trichrome lightscopy. Conclusion:The OPN expression in rat CAN model was significantly up-regulated. The in vivo RNA interference inhibited the OPN expression. Inhibition of OPN can protect the allograft from pathogenesis of EMT and IF/TA in CAN.%目的:探讨骨桥蛋白(osteopontin,OPN)的shRNA干扰质粒在大鼠慢性移植肾肾病(chronic allograft nephropathy,CAN)模型中对大鼠移植肾上皮细胞向间充质转分化(epithelial to mesenchymal transition,EMT)的作用,初步探讨OPN在慢性移植物肾病中的作用及机制.方法:以F344大鼠为供体,Lewis大鼠为受体,行原位异体肾移植术,建立大鼠CAN模型(Allo组),以Lewis大鼠做供、受体作为同系移植对照(Syn组),以基于流体力学为基础

  12. 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.

  13. Mannan binding lectin : a two-faced regulator of renal allograft injury?

    NARCIS (Netherlands)

    Damman, Jeffrey; Seelen, Marc A.

    2013-01-01

    Complement activation plays an important role in the pathogenesis of renal allograft injury after kidney transplantation. There are three known pathways of complement activation, namely, classical, alternative, and lectin pathways. In renal allograft injury, contradictory results were reported about

  14. Banking of massive osteoarticular and intercalary bone allografts--12 years' experience.

    Science.gov (United States)

    Malinin, T I; Martinez, O V; Brown, M D

    1985-01-01

    Preparation and banking of massive osteoarticular allografts and intercalary bone allografts have been performed for the past 12 years. Careful selection of donors as well as extensive laboratory studies of the donor and the allograft have virtually eliminated the danger of transmitting disease from the donor to the recipient. The availability of a variety of allografts in the Tissue Bank allows for the selection, on an anatomic basis, of an allograft best suited for a particular recipient. The authors have supplied several hundred allografts to recipients in many institutions on the premise that excision, preparation, banking, and implantation of bone allografts constitute a clinical service. Thus, the surgeon who excises and prepares the allograft assumes a joint responsibility for the care of the recipient with the surgeon who implants the allograft. This establishes a close working relationship, which encourages frequent consultation between the parties concerned. This relationship is of particular importance in the initial evaluation of the patient and in determining which particular allograft will best serve a given patient. The experience at the authors' institution provides a model for a multiinstitutional facility that may serve as a base for discussion of the methodology involved in the excision, preparation, and storage of bone allografts. The costs associated with the operation of such a facility are not inconsiderable, but the cost of individual osteoarticular and intercalary allografts can be brought down by an increase in the efficiency of operation inherent in the processing of allografts from over 100 donors per year. During the past several years, the cost of excising and preparing intercalary allografts has been $600 per implant, while the cost for osteochondral allografts varied between $900 and $1,200. Such a large multiinstitutional facility offers the advantages of readily available allografts and quality control. However, because of the

  15. Donor Heart Treatment With COMP-Ang1 Limits Ischemia-Reperfusion Injury and Rejection of Cardiac Allografts.

    Science.gov (United States)

    Syrjälä, S O; Nykänen, A I; Tuuminen, R; Raissadati, A; Keränen, M A I; Arnaudova, R; Krebs, R; Koh, G Y; Alitalo, K; Lemström, K B

    2015-08-01

    The major cause of death during the first year after heart transplantation is primary graft dysfunction due to preservation and ischemia-reperfusion injury (IRI). Angiopoietin-1 is a Tie2 receptor-binding paracrine growth factor with anti-inflammatory properties and indispensable roles in vascular development and stability. We used a stable variant of angiopoietin-1 (COMP-Ang1) to test whether ex vivo intracoronary treatment with a single dose of COMP-Ang1 in donor Dark Agouti rat heart subjected to 4-h cold ischemia would prevent microvascular dysfunction and inflammatory responses in the fully allogeneic recipient Wistar Furth rat. COMP-Ang1 reduced endothelial cell-cell junction disruption of the donor heart in transmission electron microscopy during 4-h cold ischemia, improved myocardial reflow, and reduced microvascular leakage and cardiomyocyte injury of transplanted allografts during IRI. Concurrently, the treatment reduced expression of danger signals, dendritic cell maturation markers, endothelial cell adhesion molecule VCAM-1 and RhoA/Rho-associated protein kinase activation and the influx of macrophages and neutrophils. Furthermore, COMP-Ang1 treatment provided sustained anti-inflammatory effects during acute rejection and prevented the development of cardiac fibrosis and allograft vasculopathy. These results suggest donor heart treatment with COMP-Ang1 having important clinical implications in the prevention of primary and subsequent long-term injury and dysfunction in cardiac allografts. PMID:25932532

  16. A single center's approach to discriminating donor versus host origin of renal neoplasia in the allograft kidney.

    Science.gov (United States)

    Robin, Adam J; Cohen, Eric P; Chongkrairatanakul, Tepsiri; Saad, Ehad; Mackinnon, A Craig

    2016-08-01

    Renal cell carcinoma (RCC) in the allograft of kidney transplant recipient (KTR) patients is rare and may represent a de novo process arising from the transplanted organ or metastasis from a clinically undetectable host primary. Determination of host versus donor origin is important for staging and management. We report our experience utilizing Penta-C (PC) and Penta-D (PD) short-tandem repeat (STR) microsatellite analysis to discriminate between host and donor origin of RCC identified in renal allografts. We identified 5 KTR patients with RCC in the allograft kidney. The PC and PD microsatellite analysis was applied to tumor, host, and donor formalin-fixed, paraffin-embedded tissue sections and/or fresh blood leukocytes to identify the origin of the neoplastic cells. The PC and PD microsatellite alleles were robustly amplified in all samples. Each case showed one or more informative alleles indicating that the neoplastic cells originate from donor tissue. Allele frequency data indicate that by using both PC and PD markers, we will be able to discriminate between host and donor cell of origin in over 99% of cases. The PC and PD microsatellite analysis is a convenient, robust, and efficient strategy to determine donor versus host origin or RCC in transplant kidney specimens. PMID:27402221

  17. Adenosine triphosphate-competitive mTOR inhibitors: a new class of immunosuppressive agents that inhibit allograft rejection.

    Science.gov (United States)

    Rosborough, B R; Raïch-Regué, D; Liu, Q; Venkataramanan, R; Turnquist, H R; Thomson, A W

    2014-09-01

    The mechanistic/mammalian target of rapamycin (mTOR) is inhibited clinically to suppress T cell function and prevent allograft rejection. mTOR is the kinase subunit of two mTOR-containing complexes, mTOR complex (mTORC) 1 and 2. Although mTORC1 is inhibited by the macrolide immunosuppressant rapamycin (RAPA), its efficacy may be limited by its inability to block mTORC1 completely and its limited effect on mTORC2. Adenosine triphosphate (ATP)-competitive mTOR inhibitors are an emerging class of mTOR inhibitors that compete with ATP at the mTOR active site and inhibit any mTOR-containing complex. Since this class of compounds has not been investigated for their immunosuppressive potential, our goal was to determine the influence of a prototypic ATP-competitive mTOR inhibitor on allograft survival. AZD8055 proved to be a potent suppressor of T cell proliferation. Moreover, a short, 10-day course of the agent successfully prolonged murine MHC-mismatched, vascularized heart transplant survival. This therapeutic effect was associated with increased graft-infiltrating regulatory T cells and reduced CD4(+) and CD8(+) T cell interferon-γ production. These studies establish for the first time, that ATP-competitive mTOR inhibition can prolong organ allograft survival and warrant further investigation of this next generation mTOR inhibitors. PMID:25307040

  18. Prolongation of Cardiac Allograft Survival in Rats by Treatment with Anti-Interleukin 2 Antiserum

    OpenAIRE

    Osaki, Toshihide; Sakagami, Kenichi; Orita,Kunzo

    1988-01-01

    Interleukin-2 (IL2) is the obligatory signal for both T cell mitogenesis and in vitro generation of alloreactive cytotoxic T lymphocytes (CTL). An investigation was made to determine whether an antibody directed against IL2 would suppress the rejection reaction of rat cardiac allografts. Rabbit anti-interleukin 2 (anti-IL2) antiserum was obtained by immunizing at 2 week intervals over a period of 8 weeks with 10(6) U of recombinant human IL2 along with complete Freund's adjuvant. The bioassay...

  19. Prolongation of Cardiac Allograft Survival in Rats by Treatment with Anti-Interleukin 2 Antiserum

    Directory of Open Access Journals (Sweden)

    Osaki,Toshihide

    1988-04-01

    Full Text Available Interleukin-2 (IL2 is the obligatory signal for both T cell mitogenesis and in vitro generation of alloreactive cytotoxic T lymphocytes (CTL. An investigation was made to determine whether an antibody directed against IL2 would suppress the rejection reaction of rat cardiac allografts. Rabbit anti-interleukin 2 (anti-IL2 antiserum was obtained by immunizing at 2 week intervals over a period of 8 weeks with 10(6 U of recombinant human IL2 along with complete Freund's adjuvant. The bioassay for inhibition of IL2 activity by anti-IL2 antiserum was carried out in conjunction with the IL2-dependent cytotoxic T cell (CTLL cell assay. Cardiac allografts of F344 rats were heterotopically transplanted into ACI rats. Seven daily doses of 1 ml of anti-IL2 antiserum were administered intravenously following transplantation. IL2-driven [3H]thymidine incorporation in CTLL cells was significantly inhibited by rabbit anti-IL2 antiserum. Graft survival in the anti-IL2 serum-treated group was significantly prolonged in a dose-dependent fashion compared to control groups. In conclusion, these results indicate that rabbit anti-IL2 antiserum may prove to be of significant value as an immunosuppressive agent in clinical organ transplantation.

  20. 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.

  1. Oral hydrogen water prevents chronic allograft nephropathy in rats.

    Science.gov (United States)

    Cardinal, Jon S; Zhan, Jianghua; Wang, Yinna; Sugimoto, Ryujiro; Tsung, Allan; McCurry, Kenneth R; Billiar, Timothy R; Nakao, Atsunori

    2010-01-01

    Reactive oxygen species (ROS) contribute to the development of interstitial fibrosis and tubular atrophy seen in chronic allograft nephropathy (CAN). As molecular hydrogen gas can act as a scavenger of ROS, we tested the effect of treatment with hydrogen water (HW) in a model of kidney transplantation, in which allografts from Lewis rats were orthotopically transplanted into Brown Norway recipients that had undergone bilateral nephrectomy. Molecular hydrogen was dissolved in water and recipients were given HW from day 0 until day 150. Rats that were treated with regular water (RW) gradually developed proteinuria and their creatinine clearance declined, ultimately leading to graft failure secondary to CAN. In contrast, treatment with HW improved allograft function, slowed the progression of CAN, reduced oxidant injury and inflammatory mediator production, and improved overall survival. Inflammatory signaling pathways, such as mitogen-activated protein kinases, were less activated in renal allografts from HW-treated rats as compared with RW-treated rats. Hence, oral HW is an effective antioxidant and antiinflammatory agent that prevented CAN, improved survival of rat renal allografts, and may be of therapeutic value in the setting of transplantation. PMID:19907413

  2. 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. PMID:1389780

  3. 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.

  4. The effect of gamma irradiation on the biological properties of intervertebral disc allografts: in vitro and in vivo studies in a beagle model.

    Directory of Open Access Journals (Sweden)

    Yu Ding

    Full Text Available STUDY DESIGN: An animal experiment about intervertebral disc allograft. OBJECTIVE: To explore the feasibility to decellularize disc allografts treated by 6°Co Gamma Irradiation, and simultaneously, to assess the possibility to make use of the decellularized natural disc scaffold for disc degeneration biotherapy. SUMMARY OF BACKGROUND DATA: Studies of both animal and human disc allograft transplantation indicated that the disc allograft may serve as a scaffold to undertake the physiological responsibility of the segment. METHODS: Experiment in vitro: 48 discs of beagles were harvested and divided randomly into four groups including a control group and three irradiated groups. Immediate cell viability and biomechanical properties of the discs were checked and comparisons were made among these groups. Experiment in vivo: 24 beagles accepted single-level allografted disc treated with different doses of gamma irradiation. Plain X-rays and MRIs were taken before and after surgery. Then, the spinal columns were harvested en bloc from the sacrificed beagles and were examined morphologically. RESULTS: There were significant differences of both the annulus fibrosus and nucleus pulposus immediate cell viabilities among the various groups. There were no obvious differences of the biomechanical properties among the four groups. The disc height and range of motion decreased significantly in all groups as time went on. The observed indexes in irradiated groups were much smaller than those in the control group, but the indexes in 18-kGy group were larger than those in 25-kGy and 50-kGy groups. Both MRI and macroscopic findings showed that the segmental degeneration in the control and 18-kGy group was less severe than that in 25-kGy and 50-kGy groups. CONCLUSION: Gamma Irradiation can decellularize disc allograft successfully to provide natural scaffold for the study of degenerative disc disease therapy, and also can be used as an effective method to produce

  5. 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...

  6. 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),

  7. 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.

  8. Premalignant and Malignant Skin Lesions in Two Recipients of Vascularized Composite Tissue Allografts (Face, Hands).

    Science.gov (United States)

    Kanitakis, Jean; Petruzzo, Palmina; Gazarian, Aram; Testelin, Sylvie; Devauchelle, Bernard; Badet, Lionel; Dubernard, Jean-Michel; Morelon, Emmanuel

    2015-01-01

    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. PMID:26550517

  9. 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.

  10. Allograft islet cell transplantation and postoperatively modified Edmonton protocol for 3 cases of type 1 diabetes mellitus%同种胰岛细胞移植及采用改良Edmonton方案治疗1型糖尿病三例

    Institute of Scientific and Technical Information of China (English)

    黄孝伦; 姚豫桐; 罗兰云; 薛华; 邹海波; 魏玲玲; 杨卯竹; 骆乐; 王冠

    2014-01-01

    Objective To investigate the pancreatic islet cell isolation technology,quality standards,and safety and effectiveness of allograft islet cell transplantation and modified Edmonton protocol in the treatment of type 1 diabetes (T1DM).Method Three cases of T1DM received allograft islet cell transplantation.The pancreas was taken from adult organ donation after cardiac death donor.All pancreatic organs were digested by Liberase enzyme,COBE 2991 cell separator,and discontinuous density gradient purification,to obtain high purity and high activity of islet cells.All these procedures were conducted in our GMP facilities.After culture for 12 h,testing islets reached transplant standards.After the percutaneous puncture of hepatic portal vein trunk of the recipients,islet cells were transplanted evenly through the portal vein into the liver of recipients.After islet cell transplantation,a modified Edmonton immunosuppressive protocol containing antithymocyte globulin (ATG),tacrolimus and mycophenolate mofetil was used,and the changes in blood glucose,C peptide and glycate hemoglobin were monitored regularly during a follow-up period of one year.Result The transplanted islet cells of 3 recipients were 460 00(-505 200 IEQ,and islet purity and viability were 38.5%-49.7% and 95%-97% respectively.The stimulation index of human islet was 2.8-5.4.The glucose levels of 3 recipients in the normal diet were strictly controlled below 7.8 mmol/L.Two recipients remained insulin-independent after 3-5 months.The dosage of insulin was decreased by 60% in 1 patient after 12 months.The levels of C-peptide and HbA1c were all within normal range and renal functions were improved.No complications related to islet infusion including hypoglycemia,adverse drug reactions,acute rejection and infection were observed.Conclusion Our isolation techniques and methods of islet cells are reliable.Allograft islet cell transplantation and the improved Edmonton protocol in the short-term for

  11. Apparatus for measuring the finite load-deformation behavior of a sheet of epithelial cells cultured on a mesoscopic freestanding elastomer membrane

    International Nuclear Information System (INIS)

    Details are given for the design, calibration, and operation of an apparatus for measuring the finite load-deformation behavior of a sheet of living epithelial cells cultured on a mesoscopic freestanding elastomer membrane, 10 μm thick and 5 mm in diameter. Although similar in concept to bulge tests used to investigate the mechanical properties of micromachined thin films, cell-elastomer composite diaphragm inflation tests pose a unique set of experimental challenges. Composite diaphragm (CD) specimens are extremely compliant (EMIN=0 μl, VMAX≤40 μl) while simultaneously recording the inflation pressure acting at the fixed boundary of the specimen, p(r=a). Using a carefully prescribed six-cycle inflation test protocol, the apparatus is shown to be capable of measuring the [V,p(r=a)] inflation response of a cell-elastomer CD with random uncertainties estimated at ±0.45 μl and ±2.5 Pa, respectively

  12. Soaking morselized allograft in bisphosphonate can impair implant fixation

    DEFF Research Database (Denmark)

    Jakobsen, Thomas; Baas, Jørgen; Bechtold, Joan E;

    2007-01-01

    biomechanical implant fixation and graft incorporation. In 10 dogs, a pair of titanium implants surrounded by a 2.5-mm gap was inserted into the proximal part of each humerus during two separate surgeries to allow two observation periods. The gap was filled with impacted, morselized allograft soaked in either...... implants was observed for 12 weeks and the second pair for 4 weeks. Implants were evaluated by histomorphometry and biomechanical pushout test. We found substantially decreased biomechanical implant fixation for all implants surrounded by impacted, morselized allograft that had been soaked in alendronate...

  13. Lateral Meniscal Allograft Transplantation: The Bone Trough Technique.

    Science.gov (United States)

    Chahla, Jorge; Olivetto, Javier; Dean, Chase S; Serra Cruz, Raphael; LaPrade, Robert F

    2016-04-01

    The lateral meniscus plays a critical role in the stability and health of the knee. Treating patients who have undergone a total lateral meniscectomy or functional equivalent is challenging, especially young and active patients. Current literature regarding meniscal tears supports that repair should be the first surgical option. Moreover, it is recommended to preserve as much meniscal tissue as possible. In cases in which a total or functional meniscectomy is a pre-existing condition, a lateral meniscal allograft transplantation is a possible option. The purpose of this surgical technique description was to detail the method of lateral meniscal allograft transplantation using a bone trough. PMID:27462536

  14. 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

  15. 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.

  16. Analysis of the immune status in the recipients with long-term well-functioning kidneys allografts.

    Directory of Open Access Journals (Sweden)

    Nakagawa K

    2001-02-01

    Full Text Available The immune status of thirteen living and related kidney transplant recipients with stable allografts were examined. The immunological assays consisted of a mixed lymphocyte reaction (MLR, cell-mediated lympholysis (CML assay, interleukin-2 (IL-2 production in mixed lymphocytes culture (MLC and IL-2 receptor (IL-2 R expression on MLC cells. The suppression rates of the monoclonal antibodies (mAbs against IL-2 R were tested on MLRs. The stimulation indices (SI of the MLR against both donor and third-party cells increased compared with those of pretransplantation. The MLC responder cells stimulated by donor cells produced detectable amounts of IL-2, these amounts were lower than those by third-party cells. The MLC cells against donor cells expressed IL-2 R alpha and beta chains to the same degree as those against third-party cells. Anti-IL-2 R mAbs equally inhibited the MLRs between recipient and donor or third-party cells. Cytotoxic T lymphocytes (CTL against donor cells were not generated, even with the addition of recombinant IL-2 in any of recipients except one, while anti-donor CTL had been detected prior to transplantation and the CTL against third-party cells were induced in posttranspalnt CML assays. These results indicate that the clonal anergy phenomenon might mediate the specific CTL unresponsiveness observed in kidney transplant recipients and the anergy phenomenon might serve in the long-term acceptance of allograft.

  17. 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.).

  18. Honey preserved cortical allografts in the repair of diaphyseal femoral defect in dogs: clinical and radiographic

    International Nuclear Information System (INIS)

    Fourteen adult mongrel dogs were used to evaluate the honey preserved cortical allografts in the repair of diaphyseal femoral defect. The allografts were inserted into a 5cm segmental defect created in the mid-diaphysis of the right femur in each dog. The bones were stabilized with a dynamic compression plate and eight bone screws. Healing was followed clinically and femora were evaluated radiographically, periodically. Nineteen (79.2%) of the twenty-four host-graft interfaces were radiographically incorporated. Average time to allograft incorporation was 67.1 days (range 45 days to 90 days). There was no statistical difference in the allograft incorporation time between proximal and distal host-graft interfaces. Complications observed were nonunion, allograft fracture, and allograft resorption. The conclusion is that despite the complications, honey preserved cortical allografts are a viable option to bone reconstruction

  19. 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...

  20. GASN sheets

    International Nuclear Information System (INIS)

    This document gathers around 50 detailed sheets which describe and present various aspects, data and information related to the nuclear sector or, more generally to energy. The following items are addressed: natural and artificial radioactive environment, evolution of energy needs in the world, radioactive wastes, which energy for France tomorrow, the consequences in France of the Chernobyl accident, ammunitions containing depleted uranium, processing and recycling of used nuclear fuel, transport of radioactive materials, seismic risk for the basic nuclear installations, radon, the precautionary principle, the issue of low doses, the EPR, the greenhouse effect, the Oklo nuclear reactors, ITER on the way towards fusion reactors, simulation and nuclear deterrence, crisis management in the nuclear field, does nuclear research put a break on the development of renewable energies by monopolizing funding, nuclear safety and security, the plutonium, generation IV reactors, comparison of different modes of electricity production, medical exposure to ionizing radiations, the control of nuclear activities, food preservation by ionization, photovoltaic solar collectors, the Polonium 210, the dismantling of nuclear installations, wind energy, desalination and nuclear reactors, from non-communication to transparency about nuclear safety, the Jules Horowitz reactor, CO2 capture and storage, hydrogen, solar energy, the radium, the subcontractors of maintenance of the nuclear fleet, biomass, internal radio-contamination, epidemiological studies, submarine nuclear propulsion, sea energy, the Three Mile Island accident, the Chernobyl accident, the Fukushima accident, the nuclear after Fukushima

  1. Efficacy of total lymphoid irradiation for chronic allograft rejection following bilateral lung transplantation

    International Nuclear Information System (INIS)

    Purpose: To assess the safety and efficacy of total lymphoid irradiation (TLI) in patients experiencing chronic rejection following bilateral lung transplantation (BLT). Patients and Materials: Eleven patients received TLI for chronic allograft rejection (bronchiolitis obliterans syndrome) refractory to conventional treatment modalities. Radiation therapy (RT) was prescribed as 8 Gy delivered in 10 0.8-Gy fractions, 2 fractions/week, via mantle, paraaortic, and inverted-Y fields. Serial pre- and post-RT pulmonary function values, complete blood counts, and immunosuppressive augmentation requirements [use of methylprednisolone, murine anti-human mature T-cell monoclonal antibody (OKT3), polyclonal antithymocyte globulin (ATG), and tacrolimus] were monitored. Results: In the 3 months preceding TLI, the average decrease in forced expiratory volume in 1 s (FEV1) was 34% (range 0-75%) and the median number of immunosuppression augmentations was 3 (range 0-5). Only 4 of 11 patients completed all 10 TLI treatment fractions. Reasons for discontinuation included progressive pulmonary decline (four patients), worsening pulmonary infection (two patients), and persistent thrombocytopenia (one patient). Seven of the 11 patients failed within 8 weeks of treatment cessation. One patient had unabated rejection and received bilateral living related-donor transplants; he is alive and well. Six patients died. Two of these deaths were due to pulmonary infection from organisms isolated prior to the start of RT; the other four deaths were from progressive pulmonary decline. The four remaining patients had durable positive responses to TLI (mean follow-up of 47 weeks; range 24-72). Comparing the 3 months preceding RT to the 3 months following treatment, these four patients had improvements in average FEV1 (40% decline vs. 1% improvement) and fewer median number of immunosuppressive augmentations (3.5 vs. 0). None of these patients has developed lymphoproliferative disease or has died

  2. 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.

  3. Coronary artery bypass with glycerol-preserved saphenous vein allografts

    OpenAIRE

    Bortolotti, Uberto; Casarotto, Dino; Frugoni, Carlo; De Mozzi, Pierluigi; Thiene, Gaetano; Gallucci, Vincenzo

    1981-01-01

    Over a 2-year period, 19 patients whose autologous saphenous veins were either unsuitable or unavailable underwent myocardial revascularization with saphenous vein allografts (SVAs) at our institution. All SVAs had been preserved in 98% glycerol at room temperature for at least 3 weeks (average, 7 weeks); before use, they were rinsed with saline and antibiotic solution.

  4. 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

  5. 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.

  6. Effect of allograft compound vertebra on vertebral reconstruction in rabbits

    Institute of Scientific and Technical Information of China (English)

    ZHOU Pang-hu; LIU Shi-qing; MING Jiang-hua

    2007-01-01

    Objective: To study the effect of allograft compound vertebra on vertebral reconstruction in rabbits so as to provide biomechanical direction for manufacturing and selecting vertebral reconstruction materials.Methods: Twenty-five healthy New Zealand white rabbits were divided randomly into three groups: normal group ( Group A, n = 5), iliac bone graft group ( Group B,n = 10) and allograft compound vertebra group ( Group C,n = 10). After C4 was resected, iliac bone implantation and allograft bone cage transplantation were fulfilled in Group B and Group C, respectively. Every 5 rabbits from Group B and Group C were selected to test the biomechanical strength and biological activity one and two months postoperatively.Results: No significant statistical difference was found between Group A and Group C one and two months postoperatively (P > 0.05). The biomechanical strength of Group B was much weaker than that of Group A and Group C one month postoperatively ( P < 0.05 ), but at two months postoperatively, no statistical difference was found among the three groups. The biological activity and vertebral moulding ability of Group C were better than those of Group B at one and two months postoperatively.Conclusions: Compound vertebra, which is made up of allograft cortical bone cage and autogenous cancellous bone, shows instantaneous and permanent biomechanical stability and biological activity, therefore, it is an ideal material for vertebral reconstruction.

  7. 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.

  8. 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.

  9. Comparison of Osteogenesis between Adipose-Derived Mesenchymal Stem Cells and Their Sheets on Poly-ε-Caprolactone/β-Tricalcium Phosphate Composite Scaffolds in Canine Bone Defects.

    Science.gov (United States)

    Kim, Yongsun; Lee, Seung Hoon; Kang, Byung-Jae; Kim, Wan Hee; Yun, Hui-Suk; Kweon, Oh-Kyeong

    2016-01-01

    Multipotent mesenchymal stem cells (MSCs) and MSC sheets have effective potentials of bone regeneration. Composite polymer/ceramic scaffolds such as poly-ε-caprolactone (PCL)/β-tricalcium phosphate (β-TCP) are widely used to repair large bone defects. The present study investigated the in vitro osteogenic potential of canine adipose-derived MSCs (Ad-MSCs) and Ad-MSC sheets. Composite PCL/β-TCP scaffolds seeded with Ad-MSCs or wrapped with osteogenic Ad-MSC sheets (OCS) were also fabricated and their osteogenic potential was assessed following transplantation into critical-sized bone defects in dogs. The alkaline phosphatase (ALP) activity of osteogenic Ad-MSCs (O-MSCs) and OCS was significantly higher than that of undifferentiated Ad-MSCs (U-MSCs). The ALP, runt-related transcription factor 2, osteopontin, and bone morphogenetic protein 7 mRNA levels were upregulated in O-MSCs and OCS as compared to U-MSCs. In a segmental bone defect, the amount of newly formed bone was greater in PCL/β-TCP/OCS and PCL/β-TCP/O-MSCs/OCS than in the other groups. The OCS exhibit strong osteogenic capacity, and OCS combined with a PCL/β-TCP composite scaffold stimulated new bone formation in a critical-sized bone defect. These results suggest that the PCL/β-TCP/OCS composite has potential clinical applications in bone regeneration and can be used as an alternative treatment modality in bone tissue engineering. PMID:27610141

  10. 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

  11. Skin allograft and vascularized composite allograft: potential for long-term efficacy in the context of lymphatic modulation.

    Science.gov (United States)

    Rinkinen, Jacob; Selley, Ryan; Agarwal, Shailesh; Loder, Shawn; Levi, Benjamin

    2014-01-01

    Tissue transplantation restores form and function in burn patients. The treatment of burn injuries is influenced by severity, location, and the percentage of total body surface area. There have been a number of different techniques developed to temporize and repair the destroyed tissue. However, in patients with large wound burden, sufficient donor site tissue may not be available for autograft harvesting. Such extensive burns necessitate other temporary and permanent options for wound coverage such as skin or vascularized composite allografts (VCA). Rejection of these tissues presents an ongoing problem which is currently managed using a host of systemic immunosuppressive medications. This article discusses the mechanism behind the innate and adaptive immune systems rejection of the allografts. By understanding these pathways, various techniques using immunomodulatory protocols have led to increased allograft survival. However, our primary interest lies in the initial recognition of the graft. We tailor this article to have a specific emphasis on lymphatic modulation as a potential adjunctive therapy. Reviews of the studies evaluating the effect of lymph node modulation on graft survival are described with future implications to allograft transplant research. PMID:25051523

  12. 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.

  13. 亲属供体角膜缘移植治疗化学烧伤致角膜缘衰竭的初步疗效%Limbal allografting from related live donors for limbal stem cell deficiency secondary to ocular chemical burn

    Institute of Scientific and Technical Information of China (English)

    黄挺; 杨仕庆; 高娜; 王玉娟

    2010-01-01

    Objective To investigate the efficacy and complications of limbal allografting from related live donors (RL-LAT) for limbal stem cell deficiency secondary to ocular chemical burn. Methods Retrospective comparative case series. Limbal allografting from related live human leukocyte antigen ( HLA)-matched ( n = 10) and-unmatched donors ( n = 2) was performed in 12 consecutive patients (12 eyes) with limbal stem cell deficiency secondary to ocular chemical burn, including 9 alkali burn and 3 acid burn; whereas allolimbal cadaver transplant was performed in another 15 patients in Zhongshan Ophthalmic Center between April 2006 to December 2007. Systemic cyclosporine A was administered to later eight recipients in living related donor group and all patients in cadaver donor group. Main outcome measures were restoration of corneal epithelium, reduction in corneal vascularization, improved corneal clarity, and visual improvement. Mean follow-up was (11.4 ±3.6) months (from 12 to 27). Results In living related donor group, ten patients (83.3%) achieved initially reepithelialize, and epithelial healing time was (9. 6 ± 3.4 ) d. Nine patients ( 75.0% ) achieved stable ocular surface ( stable corneal epithelium,decreased vascularization of corneal surface, and reduced corneal opacification). However, in seven eyes (77. 8% ) achieved stable ocular surface, gradual recurrence of peripheral corneal vascularization occurred after 5 to 8 months postoperatively. Whereas in cadaver donor group, twelve patients ( 80. 0% ) achieved initially reepithelialize, and epithelial healing time was ( 11.2 ±4. 6) d. Seven patients (46. 7% ) achieved stable ocular surface. However, in all seven eyes achieved stable ocular surface, gradual recurrence of peripheral corneal vascularization occurred after 4 to 10 months postoperatively. The differences of both the rate of initially reepithelialize and epithelial healing time between these two groups showed no statistical significance( χ2 = 1

  14. 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.

  15. Immune responses on allograft heart transplantation in inbred rats infected with Echinococcosis multilocularis

    Institute of Scientific and Technical Information of China (English)

    Mai Hepiretihan·Ai Erken; ZHAO Jin-ming; GUAN Xiao-yan; WEN Hao; WANG Yun-hai

    2012-01-01

    Background Alveolar echinococcosis (AE) is caused by the metacestode stage of Echinococcus multilocularis (E.multilocularis) and is a rare but life-threatening disease.This disease commonly is characterized by an infiltrative,tumor-like growth of the E.multilocularis metacestode in the liver of human.Liver transplantation is an effective therapy for end-stage of hepatic AE,but the characteristics of host immunity associated with E.multilocularis infection with organ transplantation are poorly defined.We hereby aimed to study the immunological status and allograft heart survival in inbred rats with E.multilocularis infection.Methods Rat models of AE were established by injecting the E.multilocularis suspension made from E.multilocularis infected tissues into the abdomen of Lewis (LEW) rats.Three months later,in the experimental group,allograft heart transplantation was performed from Brown-Norway (BN) rats to the E.multilocularis infected LEW rats.In the control group,we transplanted hearts from BN rats to healthy LEW rats.The influence of the disturbed immune system in E.multilocularis infected rats on the heart transplantation was assessed,including observation of allograft heart survival time,histopathological examination of grafts and immunohistochemical examination of infiltrating cells (CD4+ T cells,CD8+ T cells and eosinophile granulocytes),measurement of interleukin (IL)-4 and interferon (IFN)-Y in the serum by enzyme-linked immunosorbent assay (ELISA) and analysis of CD4+CD25+ regulatory T cells in peripheral blood by fluorescence activated cell sorting (FACS) flow cytometric analysis.Results The survival time of recipients in the experimental group was prolonged compared with those in the control group.The numbers of graft infiltrating CD8+ T cells were decreased whereas the graft infiltrating eosinophil granulocytes (CD15+) were increased in grafts in the experimental group (P <0.05).Furthermore,the proportion of CD4+CD25+ regulatory T cells in the

  16. 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

  17. 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.

  18. Freeze-dried fibular allograft in anterior spinal surgery: cervical and lumbar applications.

    OpenAIRE

    Wetzel, F.T.; Hoffman, M. A.; Arcieri, R. R.

    1993-01-01

    Fifty-six patients who underwent anterior fusion utilizing fibular allograft are reviewed. Thirty-two patients underwent multiple-level anterior cervical discectomy and fusion utilizing fibular strut allograft, and 24 underwent anterior lumbar discectomy and fusion using fibular strut allograft. Cervical surgery was performed via the strut technique of Whitecloud and LaRocca and lumbar surgery was performed via a transperitoneal or retroperitoneal approach. Postoperatively, patients were assi...

  19. 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.

  20. Healing properties of allograft from alendronate-treated animal in lumbar spine interbody cage fusion

    OpenAIRE

    Xue, Qingyun; Li, Haisheng; Zou, Xuenong; Bünger, Mathias; Egund, Niels; Lind, Martin; Christensen, Finn Bjarke; Bünger, Cody

    2004-01-01

    This study investigated the healing potential of allograft from bisphosphonate-treated animals in anterior lumbar spine interbody fusion. Three levels of anterior lumbar interbody fusion with Brantigan cages were performed in two groups of five landrace pigs. Empty Brantigan cages or cages filled with either autograft or allograft were located randomly at different levels. The allograft materials for the treatment group were taken from the pigs that had been fed with alendronate, 10 mg daily ...

  1. 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. PMID:11770503

  2. 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

  3. Structural Biology Fact Sheet

    Science.gov (United States)

    ... 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 ...

  4. 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...

  5. 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....

  6. Healing properties of allograft from alendronate-treated animal in lumbar spine interbody cage fusion.

    Science.gov (United States)

    Xue, Qingyun; Li, Haisheng; Zou, Xuenong; Bünger, Mathias; Egund, Niels; Lind, Martin; Christensen, Finn Bjarke; Bünger, Cody

    2005-04-01

    This study investigated the healing potential of allograft from bisphosphonate-treated animals in anterior lumbar spine interbody fusion. Three levels of anterior lumbar interbody fusion with Brantigan cages were performed in two groups of five landrace pigs. Empty Brantigan cages or cages filled with either autograft or allograft were located randomly at different levels. The allograft materials for the treatment group were taken from the pigs that had been fed with alendronate, 10 mg daily for 3 months. The histological fusion rate was 2/5 in alendronate-treated allograft and 3/5 in non-treated allograft. The mean bone volume was 39% and 37.2% in alendronate-treated or non-treated allograft (NS), respectively. No statistical difference was found between the same grafted cage comparing two groups. The histological fusion rate was 7/10 in all autograft cage levels and 5/10 in combined allograft cage levels. No fusion was found at all in empty cage levels. With the numbers available, no statistically significant difference was found in histological fusion between autograft and allograft applications. There was a significant difference of mean bone volume between autograft (49.2%) and empty cage (27.5%) (P<0.01). In conclusion, this study did not demonstrate different healing properties of alendronate-treated and non-treated allograft for anterior lumbar interbody fusion in pigs. PMID:15248057

  7. 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

  8. 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.)

  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. 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.

  11. Regulatory oversight in the United States of vascularized composite allografts.

    Science.gov (United States)

    Glazier, Alexandra K

    2016-06-01

    Vascularized composite allograft (VCA) transplantation is a medically acceptable treatment for the reconstruction of major tissue loss. The advent of VCA transplantation has spurred regulatory and policy development in the United States to address the multiple clinical, ethical and legal issues that must be considered for the practice of VCA donation and transplantation to develop within the existing framework of public trust and transparency vital to the success of donation and transplantation. PMID:26284312

  12. Lumbar intervertebral disc allografting in a goat model

    OpenAIRE

    Hung, Y; Xiao, J; Luk, K.; Leung, V.; Lu, W.

    2012-01-01

    Preliminary study in humans indicated that whole fresh-frozen intervertebral disc (IVD) transplantation may be an effective treatment for disc degenerative diseases, but signs of degenerative change in the allograft were noted after the transplantation. The underlying mechanisms are not fully understood and remain a series of ongoing research in large animal model. Because of the ethically and economically accessible issues as well as anatomical similarity with human disc, the goats were used...

  13. Survival and Reoperation Rate Following Osteochondral Allograft Transplantation

    OpenAIRE

    Frank, Rachel M.; Levy, David; Scalise, Pamela Nina; Smith, Margaret Elizabeth; Cole, Brian J.

    2016-01-01

    Objectives: The purpose of this study was to quantify survival for osteochondral allograft transplantation (OAT) and report findings at reoperation. Methods: A retrospective review of a prospectively collected database of patients who underwent OAT by a single surgeon with a minimum follow-up duration of 2-years was conducted. The reoperation rate, timing of reoperation, procedure performed at reoperation, and findings at surgery were reviewed. Failure was defined by revision OAT, conversion ...

  14. 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

  15. Apparatus for measuring the finite load-deformation behavior of a sheet of epithelial cells cultured on a mesoscopic freestanding elastomer membrane

    Science.gov (United States)

    Selby, John C.; Shannon, Mark A.

    2007-09-01

    Details are given for the design, calibration, and operation of an apparatus for measuring the finite load-deformation behavior of a sheet of living epithelial cells cultured on a mesoscopic freestanding elastomer membrane, 10μm thick and 5mm in diameter. Although similar in concept to bulge tests used to investigate the mechanical properties of micromachined thin films, cell-elastomer composite diaphragm inflation tests pose a unique set of experimental challenges. Composite diaphragm (CD) specimens are extremely compliant (Epump integrated with a modular specimen mounting fixture that constitutes a horizontally semi-infinite reservoir of liquid culture medium. In a deformation-controlled inflation test, pressurized air is used to inflate a CD specimen into the liquid reservoir with minimum disturbance of the liquid-air interface. Piston displacements and absolute pump chamber air pressures are utilized as feedback to cycle the displaced (or inflated) CD volume V in a 0.05Hz triangular or sinusoidal wave form (VMIN=0μl, VMAX⩽40μl) while simultaneously recording the inflation pressure acting at the fixed boundary of the specimen, p(r =a). Using a carefully prescribed six-cycle inflation test protocol, the apparatus is shown to be capable of measuring the [V,p(r=a)] inflation response of a cell-elastomer CD with random uncertainties estimated at ±0.45μl and ±2.5Pa, respectively.

  16. 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.

  17. 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.

  18. Significance of Urinary Proteome Pattern in Renal Allograft Recipients

    Directory of Open Access Journals (Sweden)

    Sufi M. Suhail

    2014-01-01

    Full Text Available 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. Effects of silencing transforming growth factor-β1 by RNAi upon transdifferentiation of renal allograft tubular epithelial cells in rats%RNA干扰沉默转化生长因子β1对大鼠移植肾上皮细胞转分化的作用

    Institute of Scientific and Technical Information of China (English)

    夏雨果; 吴小候; 尹志康; 罗春丽; 张家模; 程洪林

    2009-01-01

    Objective To investigate the effects of shRNA-transforming growth factor(TGF)-β1 plasmid upon epithelial-myofibroblast transdifferentiation of renal allograft in rats. Methods Divided the Wistar rats into 4 groups: Group J (sham-operated group), T (plasmid group), H (vacant plasmid group) and Y (simply transplantation group). The SD to Wistar rat transplant kidney-sclerosis accelerated model was constructed and transfected with the plasmid based on hydromechanics. Transplanted kidneys were collected at Months 1, 2 and 3 post-transplantation. The gene transcriptional levels of TGF-β1 and E-cadherin were detected by RT-PCR and the protein variation of E-cadherin was examined by Western blotting. The pathological changes and infiltrated inflammatory cells were assessed by HE staining and the immunohistochemical staining of E-cadherin and α-SMA used to label epithelial cells and fibroblast in order to exhibit cell transdifferentiation. Results Compared with Group H and Y, the mRNA transcription of TGF-β1 was obviously inhibited in the Group T: at Month 3, the TGF-β1 mRNA of Group T is 0.73 ± 0.08, significantly lower than Group H and Y (0.92±0.07 and 0.95±0.04, both P < 0.01) ; the expression of E-cadherin was maintained at a high level: at the Month 3, the E-cadherin mRNA of Group T is 0.39±0.11, significantly higher than Group H and Y (0.15±0.07, and 0.17±0.06, both P < 0.01); the E-cadherin protein of Group T is 0.38±0.08, significantly higher than group H and Y (0.15±0.07 and 0.15±0.07, both P < 0.01) ; epithelial cells were much more and fibroblast was much less than that of Group H and Y; there were also less infiltrated chronic inflammatory cells and extracellular matrix deposition in the Group T. Conclusion The shRNA-TGF-β1 plasmid can inhibit the epithelial-myofibroblast transdifferentiation of renal allograft in rats. The mechanisms may be associated with its effects of down-regulating TGF-β1 and up-regulating E-cadherin.%目的

  4. Could Life Originate between Mica Sheets?

    Science.gov (United States)

    Hansma, Helen

    2014-11-01

    Muscovite mica has many advantages as a site for the origins of life. Some of these advantages are: A. Spaces between mica sheets serve as cell-like compartments. B. K+ ions bridge Muscovite mica sheets, providing a high K+ environment, as found in all living cells. C. Mica's hexagonal 0.5-nm clay crystal lattice is comparable to the length of the amino acids, sugars, and nucleotides that polymerize to form life's major biological macromolecules. D. Mechanical energy from mica sheets, moving in response to water flows and temperature changes, provide an endless energy source for forming chemical bonds, rearranging polymers, and blebbing off protocells in a primitive form of cell division. How might fluid dynamics in the planar nanometer- to micron-high spaces between mica sheets affect the processes involved in the origins of life?

  5. 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.

  6. Effect of anti-interleukin 2 monoclonal antibody treatment on the survival of rat cardiac allograft

    International Nuclear Information System (INIS)

    The effect of anti-interleukin 2 monoclonal antibody (anti-IL2 MoAb) and the accumulation of intravenously administered 125I-labeled anti-IL2 MoAb were examined in heterotopic rat cardiac allografts. Mouse anti-human recombinant IL2 MoAb was obtained by the hybridoma technique. The anti-IL2 MoAb, termed 8H-10, was an IgG2a which inhibited IL2-driven [3H]TdR incorporation in cytolytic T lymphocyte line cells at a dilution of 2(6). 8H-10 was injected iv at a dose of 200 micrograms/day for 8 consecutive days, beginning on the day of transplantation. Hearts from F344 rats (RT11v1) were transplanted into ACI recipient rats (RT1av1). The mean survival time was 7.6 +/- 0.8 days in untreated controls, 9.0 +/- 1.2 days in additional controls treated with mouse anti-sheep red blood cell monoclonal antibody, and 25.3 +/- 18.4 days in the anti-IL2 MoAb (8H-10)-treated group (P less than 0.05). Furthermore, the accumulation of intravenously administered 125I-labeled anti-IL2 MoAb (8H-10) was specifically seen in the grafted heart. In conclusion, these results suggest that IL2 may play an important role in allograft rejection and that anti-IL2 MoAb may serve as a useful immunosuppressive agent in clinical transplantation

  7. 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

  8. 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

  9. 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.

  10. 不同表面处理方法对钛表面成骨细胞膜片 ALP活性的影响%Active Changes of ALP of Osteoblasts Cell Sheet with Different Treated Titanium Surfaces

    Institute of Scientific and Technical Information of China (English)

    毛久凤; 夏茜; 吴镭; 杨红; 周成菊; 方艺; 董强

    2016-01-01

    目的:探讨不同表面处理方法对钛表面的成骨细胞膜片碱性磷酸酶( ALP)活性的影响。方法:原代培养大鼠成骨细胞,通过形态学及ALP鉴定成骨细胞;以机械抛光处理的钛片为对照组,以棕刚玉颗粒喷砂材料处理的钛片为喷砂酸蚀( SLA)组,分别构建成骨细胞膜片,膜片连续培养1周或2周时,测量成骨细胞膜片中反映成骨效应的ALP活性的改变。结果:原代培养细胞ALP阳性,经形态及特性鉴定为成骨细胞;连续培养1周或2周时,SLA组ALP活性均高于对照组,差异有统计学意义( P<0.05);各组膜片ALP活性第1周高于第2周,差异有统计学意义( P<0.05)。结论:钛表面性质能够影响成骨细胞膜片的成骨分化能力。%[ Abstract]Objective:To study the ontogenesis of osteoblasts cell sheets with different treated surface of titanium. Methods:Primary cultured rat osteoblasts were identified through morphology observa-tion,alkaline phosphatase staining. Mechanically polished titanium sheets served as control group. The cell sheets were treated with brown fused alumina material as SLA group. Constructing osteoblast cell sheets respectively,and cultured successively for 1 or 2 weeks. Then,measuring changes of ALP activity. Results:Primary cultured cell ALP was positive,the morphology of cells conformed to the characteristics of osteoblasts. The alkaline phosphatase activity of the SLA group was higher than that of control group when cultured successively for 1 or 2 weeks,differences were statistically significant ( P<0 . 05 ). The alkaline phosphatase activity of the cell sheets formed in 1 st week was higher than that of 2nd week,differences were statistically significant(P<0. 05). Conclusion:The surface prop-erties of titanium could affect the osteogenic capacity of cell sheet.

  11. 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.

  12. Scapular allograft reconstruction after total scapulectomy: surgical technique and functional results

    NARCIS (Netherlands)

    Capanna, R.; Totti, F.; Geest, I.C.M. van der; Muller, D.A.

    2015-01-01

    HYPOTHESIS: Scapular allograft reconstruction after total scapulectomy preserving the rotator cuff muscles is an oncologically safe procedure and results in good functional outcome with a low complication rate. METHODS: The data of 6 patients who underwent scapular allograft reconstruction after a t

  13. 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....

  14. A Systematic Review of Anterior Cruciate Ligament Reconstruction with Autograft Compared with Allograft

    OpenAIRE

    Carey, James L.; Dunn, Warren R.; Dahm, Diane L.; Zeger, Scott L.; Spindler, Kurt P.

    2009-01-01

    Background: Anterior cruciate ligament reconstruction can be performed with use of either autograft or allograft tissue. It is currently unclear if the outcomes of these two methods differ significantly. This systematic review and meta-analysis investigated whether the short-term clinical outcomes of anterior cruciate reconstruction with allograft were significantly different from those with autograft.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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....

  1. Prevention of allograft rejection in heart transplantation through concurrent gene silencing of TLR and Kinase signaling pathways

    Science.gov (United States)

    Wang, Hongmei; Zhang, Xusheng; Zheng, Xiufen; Lan, Zhu; Shi, Jun; Jiang, Jifu; Zwiep, Terry; Li, Qing; Quan, Douglas; Zhang, Zhu-Xu; Min, Weiping

    2016-01-01

    Toll-like receptors (TLRs) act as initiators and conductors responsible for both innate and adaptive immune responses in organ transplantation. The mammalian target of rapamycin (mTOR) is one of the most critical signaling kinases that affects broad aspects of cellular functions including metabolism, growth, and survival. Recipients (BALB/c) were treated with MyD88, TRIF and mTOR siRNA vectors, 3 and 7 days prior to heart transplantation and 7, 14 and 21 days after transplantation. After siRNA treatment, recipients received a fully MHC-mismatched C57BL/6 heart. Treatment with mTOR siRNA significantly prolonged allograft survival in heart transplantation. Moreover, the combination of mTOR siRNA with MyD88 and TRIF siRNA further extended the allograft survival; Flow cytometric analysis showed an upregulation of FoxP3 expression in spleen lymphocytes and a concurrent downregulation of CD40, CD86 expression, upregulation of PD-L1 expression in splenic dendritic cells in MyD88, TRIF and mTOR treated mice. There is significantly upregulated T cell exhaustion in T cells isolated from tolerant recipients. This study is the first demonstration of preventing immune rejection of allogeneic heart grafts through concurrent gene silencing of TLR and kinase signaling pathways, highlighting the therapeutic potential of siRNA in clinical transplantation. PMID:27659428

  2. Ankle and shoulder joint reconstruction using soft tissue allografts

    International Nuclear Information System (INIS)

    Full text: Lateral Collateral Ligament Insufficiency is a common complication of injury to the ankle joint. This needs reconstruction of the torn ligament as the joint instability gives rise to frequent giving way at the ankle joint. It can be reconstructed using autologous peroneus brevis tendon. The authors prefer to reconstruct using deep frozen (-80 degree C) non-gamma irradiated tibialis anterior or tibialis posterior tendon allograft procured by NUH Tissue Bank. The graft must be at least between 18-22 cm long. The procedure employed is a first stage Brostrom Procedure repairing the anterior talo-fibula ligament using Mitek sutures. In the second stage the Calcaneofibular ligament is reconstructed using a figure of eight tendon reconstruction via drill holes in the fibular above and the calcaneum below. Twelve cases have been reconstructed this way with good results. When injury is sustained to the Acromia-clavicular (AC) Joint, for type 3 to 5 AC Joint Dislocation and in manual labourers, reconstruction is needed. The author's preferred method is a 2 stage procedure using deep frozen (-80 degree C), non gamma-irradiated fascia lata allografts procured by NUH Tissue Bank. In the first stage the dislocated AC Joint is reduced and held in position by transfixation using 2 baby Steinmann Pins and repair of torn corac clavicular ligaments. The second stage consisted of reconstruction with rolled-up fascia lata figure of eight allograft tendon between the clavicle and the coracoid process. The 2 pins are removed after 6 weeks and the shoulder mobilised. 10 cases have been done with good results. Two cases showed mild subluxation of the AC joint due to slight loss of the reduction performed during the operation. (Author)

  3. Thermoforming of foam sheet

    OpenAIRE

    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 the sheet in the required form on the mould. This production method appears to be a very sensitive process with respect to e.g. the sheet temperature, the pressures applied and the cooling time. Mor...

  4. Perforating Thin Metal Sheets

    Science.gov (United States)

    Davidson, M. E.

    1985-01-01

    Sheets only few mils thick bonded together, punched, then debonded. Three-step process yields perforated sheets of metal. (1): Individual sheets bonded together to form laminate. (2): laminate perforated in desired geometric pattern. (3): After baking, laminate separates into individual sheets. Developed for fabricating conductive layer on blankets that collect and remove ions; however, perforated foils have other applications - as conductive surfaces on insulating materials; stiffeners and conductors in plastic laminates; reflectors in antenna dishes; supports for thermal blankets; lightweight grille cover materials; and material for mockup of components.

  5. Ice sheet in peril

    OpenAIRE

    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 ...

  6. Bone allograft and implant fixation tested under influence of bio-burden reduction, periosteal augmentation and topical antibiotics. Animal experimental studies.

    Science.gov (United States)

    Barckman, Jeppe

    2014-01-01

    Loosening of an artificial joint prosthesis is a painful and debilitating condition that can be treated only by re-operation. Re-operations accounted for approximately 15% of all hip replacement operations performed in Denmark between the year 1995 and 2010. The process of loosening is often accompanied by destructive inflammation and osteolysis, which leads to insufficient bone stock that often requires extensive bone grafting. Impacted morselized bone graft is a well-established method for improving the amount and quality of bone stock that ensures sufficient stability and anchorage of the revision implants. Among bone graft options, the autologous bone graft is considered the gold standard. It is naturally biocompatible, but its use in revision surgery is curtailed by its limited volume and by considerable donor site morbidity. Allograft bone is readily available and is the most commonly used graft material. However, it has been shown that the incorporation of allograft bone into the host bone is not always complete, and substantial fibrous tissue formation has been described. A reason for this may be that allograft bone is a foreign tissue, which, contrary to autogenic bone, may induce an immunogenic response that leads to increased fibrous tissue formation. Furthermore, the fresh-frozen allograft has minimal osteoinductive and no osteogenic capacity. The studies in this thesis have investigated ways of improving the incorporation of allograft bone by adding osteoinductive cells from the periosteum and reducing the immunogenic load of the allograft bone by rinsing. Furthermore, the impact of antibiotic protection of the bone graft has been evaluated. The same experimental implant model was used in all three studies. This model enables evaluation of early implant fixation and osseointegration of an uncemented implant surrounded by impacted morselized bone graft. Unloaded gap implants were inserted into the metaphysis of the proximal tibia (Study I) and distal

  7. 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.

  8. "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.

  9. Utility of adenovirus-mediated Fas ligand and bcl-2 gene transfer to modulate rat liver allograft survival

    Institute of Scientific and Technical Information of China (English)

    De-Sheng Wang; Yu Li; Ke-Feng Dou; Kai-Zong Li; Zhen-Shun Song

    2006-01-01

    BACKGROUND: Expression of Fas ligand (FasL) on the graft by gene transduction is expected to introduce apoptosis to lymphocytes to protect rejection, but the FasL-expressing graft cells may also induce apoptosis as the graft usually expresses Fas antigens. In this study, a strong antiapoptotic gene, bcl-2, was cotransfected with the FasL gene in rat liver graft to protect against Fas-mediated cell death and to prolong recipient survival. METHODS: Orthotopic liver transplantation was done in a strain combination of DA to LEW rats. After donor vascular isolation, adenovirus-mediated FasL and bcl-2 genes were cotransfected in the liver graft. RESULTS: Intragraft expression of FasL mRNA was constitutively expressed after adenovirus-mediated transduction, although expression of FasL increased mildly in control grafts. Bcl-2 mRNA was highly expressed at 2 days after reperfusion. In contrast, lower expression of bcl-2 was observed in the control group. The average survival of the gene transferred allografts increased from (9.8+1.3) days to (18.5+8.7) days compared with the control group. CONCLUSION: Our results indicate that rat liver allografts can be protected against host immune responses by adenovirus-mediated FasL and bcl-2 transfection, and that bcl-2 expression prevents the graft from Fas-mediated apoptosis.

  10. Infertility Fact Sheet

    Science.gov (United States)

    ... Home > ePublications > Our ePublications > Infertility fact sheet ePublications Infertility fact sheet This information in Spanish (en español) ... to the fallopian tube instead of the uterus. Gamete intrafallopian transfer (GIFT) involves transferring eggs and sperm into the ...

  11. 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

  12. 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

  13. 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.

  14. Ipsilateral Lymphadenectomy to Inhibit Corneal Allograft Rejection in Rats

    Institute of Scientific and Technical Information of China (English)

    LING Shiqi; HU Yanhua

    2005-01-01

    In order to investigate the ipsilateral lymphadenectomy for inhibiting rejection in rat corneal transplantation, corneal allogenic transplantation models were established in rats. Eighteen female Wister rats were used as donors, and 36 Sprague Dawley rats as recipients. After penetrating corneal transplantation, recipients were randomly divided into 3 groups: group A (control group);group B, the ipsilateral lymphadenectomy group; group C, the bilateral lymphadenectomy group.Among 12 rats in each group, the corneas of 2 rats in each group were used for pathological study at day 14 after the transplantation, and the remaining 10 rats were used for studying corneal rejection by a slit lamp. The time points when allograft rejection occurred were recorded and mean survival time (MST) was compared. The results showed that MST in groups B and C was 46.30±9.464 days and 44.43 ± 7. 604 days, respectively, which was significantly prolonged as compared with that in group A (10.71±1. 567 days, P<0.01). There was no significant difference in MST between groups B and C (P>0.05). Itwas concluded that both bilateral and ipsilateral lymphadenectomy therapies could effectively inhibit the corneal allograft rejection. Ipsilateral lymphadenectomy is a less complex surgical procedure and is just as effective in preventing rejection.

  15. 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. PMID:26986539

  16. 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.

  17. 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.

  18. 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.

  19. Tc-99m DTPA scans in renal allograft rejection and cyclosporine nephrotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Renal Allograft Torsion: US and CT Imaging Findings of a Rare Posttransplant Complication

    Directory of Open Access Journals (Sweden)

    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.

  1. 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 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.

  2. 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. PMID:25950536

  3. Heterojunction solar cell with 6% efficiency based on an n-type aluminum-gallium-oxide thin film and p-type sodium-doped Cu2O sheet

    Science.gov (United States)

    Minami, Tadatsugu; Nishi, Yuki; Miyata, Toshihiro

    2015-02-01

    In this paper, we describe efforts to enhance the efficiency of Cu2O-based heterojunction solar cells fabricated with an aluminum-gallium-oxide (Al-Ga-O) thin film as the n-type layer and a p-type sodium (Na)-doped Cu2O (Cu2O:Na) sheet prepared by thermally oxidizing copper sheets. The optimal Al content [X; Al/(Ga + Al) atomic ratio] of an AlX-Ga1-X-O thin-film n-type layer was found to be approximately 2.5 at. %. The optimized resistivity was approximately 15 Ω cm for n-type AlX-Ga1-X-O/p-type Cu2O:Na heterojunction solar cells. A MgF2/AZO/Al0.025-Ga0.975-O/Cu2O:Na heterojunction solar cell with 6.1% efficiency was fabricated using a 60-nm-thick n-type oxide thin-film layer and a 0.2-mm-thick Cu2O:Na sheet with the optimized resistivity.

  4. Survival and Reoperation Rate Following Osteochondral Allograft Transplantation

    Science.gov (United States)

    Frank, Rachel M.; Levy, David; Scalise, Pamela Nina; Smith, Margaret Elizabeth; Cole, Brian J.

    2016-01-01

    Objectives: The purpose of this study was to quantify survival for osteochondral allograft transplantation (OAT) and report findings at reoperation. Methods: A retrospective review of a prospectively collected database of patients who underwent OAT by a single surgeon with a minimum follow-up duration of 2-years was conducted. The reoperation rate, timing of reoperation, procedure performed at reoperation, and findings at surgery were reviewed. Failure was defined by revision OAT, conversion to knee arthroplasty, or gross appearance of graft failure at 2ndlook arthroscopy. Descriptive statistics, log-rank testing, cross-tabulation, and chi-square testing were performed, with POAT at an average follow-up of 4.9±2.5 years (range, 2.0 to 11.3) were included. Ninety-five patients (95%) underwent an average of 2.7±1.7 prior surgical procedures on the ipsilateral knee prior to OAT. The average defect size was 452.7±181.6 mm2 and was located on the medial femoral condyle in 63 patients (63%). Fifty-one percent of OATs were isolated, while 49% were performed with concomitant procedures including meniscus allograft transplantation (MAT) in 27 (27%). Fifty-three patients (53%) returned to the operating room at an average 2.8±2.7 years, with 26% of these patients (14/53) undergoing additional reoperations (range, 1-3 additional reoperations). Arthroscopic debridement was performed in 91% of the initial reoperations (48/53); 55% of reoperations (29/53) were performed within 2 years of the index OAT. Twenty patients (20%) were considered failures at an average 4.0±2.7 years following index OAT either due to revision OAT (N=6), conversion to arthroplasty (N=10), or appearance of poorly incorporated allograft at arthroscopy (N=4). Patients requiring multiple reoperations had an odds ratio of 7.25 (95% CI, 1.85 to 28.37) of OAT failure (P=0.004), while patients requiring secondary surgery within 2 years had an odds radio of 1.35 (95% CI, 0.48 to 3.82) for OAT failure (P>0

  5. Mycophenolate pharmacokinetics and pharmacodynamics in belatacept treated renal allograft recipients – a pilot study

    Directory of Open Access Journals (Sweden)

    Stenstrøm Jean

    2009-07-01

    Full Text Available Abstract Background Mycophenolic acid (MPA is widely used as part of immunosuppressive regimens following allograft transplantation. The large pharmacokinetic (PK and pharmacodynamic (PD variability and narrow therapeutic range of MPA provide a potential for therapeutic drug monitoring. The objective of this pilot study was to investigate the MPA PK and PD relation in combination with belatacept (2nd generation CTLA4-Ig or cyclosporine (CsA. Methods Seven renal allograft recipients were randomized to either belatacept (n = 4 or cyclosporine (n = 3 based immunosuppression. Samples for MPA PK and PD evaluations were collected predose and at 1, 2 and 13 weeks posttransplant. Plasma concentrations of MPA were determined by HPLC-UV. Activity of inosine monophosphate dehydrogenase (IMPDH and the expressions of two IMPDH isoforms were measured in CD4+ cells by HPLC-UV and real-time reverse-transcription PCR, respectively. Subsets of T cells were characterized by flow cytometry. Results The MPA exposure tended to be higher among belatacept patients than in CsA patients at week 1 (P = 0.057. Further, MPA concentrations (AUC0–9 h and C0 increased with time in both groups and were higher at week 13 than at week 2 (P = 0.031, n = 6. In contrast to the postdose reductions of IMPDH activity observed early posttransplant, IMPDH activity within both treatment groups was elevated throughout the dosing interval at week 13. Transient postdose increments were also observed for IMPDH1 expression, starting at week 1. Higher MPA exposure was associated with larger elevations of IMPDH1 (r = 0.81, P = 0.023, n = 7 for MPA and IMPDH1 AUC0–9 h at week 1. The maximum IMPDH1 expression was 52 (13–177% higher at week 13 compared to week 1 (P = 0.031, n = 6. One patient showed lower MPA exposure with time and did neither display elevations of IMPDH activity nor IMPDH1 expression. No difference was observed in T cell subsets between treatment groups. Conclusion The

  6. Chondroblastoma of the knee treated with resection and osteochondral allograft reconstruction.

    Science.gov (United States)

    Fitzgerald, Judd; Broehm, Cory; Chafey, David; Treme, Gehron

    2014-01-01

    Case. This case report describes the operative management of 16-year-old male with a symptomatic chondroblastoma of the distal femur with breach of the chondral surface. Following appropriate imaging and core needle biopsy, the diagnosis was confirmed histologically. The patient then underwent intralesional curettage and osteochondral allograft reconstruction of the defect. At one-year follow-up the patient was pain-free and has obtained excellent range of motion. There is radiographic evidence of allograft incorporation and no evidence of local recurrence. Conclusion. Osteochondral allograft reconstruction is an effective option following marginal resection and curettage of chondroblastoma involving the chondral surface of the distal femur. PMID:25548701

  7. Chondroblastoma of the knee treated with resection and osteochondral allograft reconstruction.

    Science.gov (United States)

    Fitzgerald, Judd; Broehm, Cory; Chafey, David; Treme, Gehron

    2014-01-01

    Case. This case report describes the operative management of 16-year-old male with a symptomatic chondroblastoma of the distal femur with breach of the chondral surface. Following appropriate imaging and core needle biopsy, the diagnosis was confirmed histologically. The patient then underwent intralesional curettage and osteochondral allograft reconstruction of the defect. At one-year follow-up the patient was pain-free and has obtained excellent range of motion. There is radiographic evidence of allograft incorporation and no evidence of local recurrence. Conclusion. Osteochondral allograft reconstruction is an effective option following marginal resection and curettage of chondroblastoma involving the chondral surface of the distal femur.

  8. Chondroblastoma of the Knee Treated with Resection and Osteochondral Allograft Reconstruction

    Directory of Open Access Journals (Sweden)

    Judd Fitzgerald

    2014-01-01

    Full Text Available Case. This case report describes the operative management of 16-year-old male with a symptomatic chondroblastoma of the distal femur with breach of the chondral surface. Following appropriate imaging and core needle biopsy, the diagnosis was confirmed histologically. The patient then underwent intralesional curettage and osteochondral allograft reconstruction of the defect. At one-year follow-up the patient was pain-free and has obtained excellent range of motion. There is radiographic evidence of allograft incorporation and no evidence of local recurrence. Conclusion. Osteochondral allograft reconstruction is an effective option following marginal resection and curettage of chondroblastoma involving the chondral surface of the distal femur.

  9. Renal allograft accumulation of Tc-99m sulfur colloid: temporal quantitation and scintigraphic assessment

    Energy Technology Data Exchange (ETDEWEB)

    George, E.A.; Meyerovitz, M.; Codd, J.E.; Fletcher, J.W.; Donati, R.M.

    1983-08-01

    Renal allograft accumulation of Tc-99m sulfur colloid (TSC) was studied using visual assessment of scintigraphic displays and a quantitative temporal model in 210 examinations of 56 transplant recipients. The quantitative temporal model related the immediate pool of the radioagent in the transplant to the fixed allograft accumulation of TSC at 20 minutes after administration. Examinations performed less than 3 days after grafting or steroid pulse therapy were excluded. Rejection was established by clinical and biochemical evaluation in all 84 examinations that showed acute or choronic allograft rejection. Rejection was accurately diagnosed by visual scintigraphic assessment in 82% of the established cases.

  10. Myoglobinuria masquerading as acute rejection in a renal allograft recipient with recurrent post transplant diabetic nephropathy.

    Science.gov (United States)

    Gupta, Pallav; Sharma, Amit; Khullar, Dinesh

    2014-08-01

    Rhabdomyolysis contributes to 7-10% of total AKI cases. Myoglobinuria as a cause of acute renal allograft dysfunction is extremely uncommon. Renal allograft recipient on cyclosporine or tacrolimus can develop myoglobinuria in presence of other precipitating factors. Present case describes an interesting report of myoglobinuria in a patient with post transplant diabetic nephropathy mimicking acute graft rejection. Clinically myoglobinuria presenting as renal allograft dysfunction is diagnosis of exclusion and renal biopsy is extremely important in making a correct diagnosis and planning optimal management in such cases.

  11. Both rejection and tolerance of allografts can occur in the absence of secondary lymphoid tissues.

    Science.gov (United States)

    Kant, Cavit D; Akiyama, Yoshinobu; Tanaka, Katsunori; Shea, Susan; Yamada, Yohei; Connolly, Sarah E; Marino, Jose; Tocco, Georges; Benichou, Gilles

    2015-02-01

    In this study, we showed that aly/aly mice, which are devoid of lymph nodes and Peyer's patches, acutely rejected fully allogeneic skin and heart grafts. They mounted potent inflammatory direct alloresponses but failed to develop indirect alloreactivity after transplantation. Remarkably, skin allografts also were rejected acutely by splenectomized aly/aly (aly/aly-spl(-)) mice devoid of all secondary lymphoid organs. In these recipients, the rejection was mediated by alloreactive CD8(+) T cells presumably primed in the bone marrow. In contrast, cardiac transplants were not rejected by aly/aly-spl(-) mice. Actually, aly/aly-spl(-) mice that spontaneously accepted a heart allotransplant and displayed donor-specific tolerance also accepted skin grafts from the same, but not a third-party, donor via a mechanism involving CD4(+) regulatory T cells producing IL-10 cytokine. Therefore, direct priming of alloreactive T cells, as well as rejection and regulatory tolerance of allogeneic transplants, can occur in recipient mice lacking secondary lymphoid organs.

  12. 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

  13. 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

  14. Mast cell degranulation breaks peripheral tolerance

    OpenAIRE

    De Vries, V. C.; Wasiuk, A.; Bennett, K A; Benson, M. J.; Elgueta, R.; Waldschmidt, T. J.; Noelle, R J

    2009-01-01

    Mast cells (MC) have been shown to mediate regulatory T-cell (T(reg))-dependent, peripheral allograft tolerance in both skin and cardiac transplants. Furthermore, T(reg) have been implicated in mitigating IgE-mediated MC degranulation, establishing a dynamic, reciprocal relationship between MC and T(reg) in controlling inflammation. In an allograft tolerance model, it is now shown that intragraft or systemic MC degranulation results in the transient loss of T(reg) suppressor activities with t...

  15. Osteogenic protein-1 increases the fixation of implants grafted with morcellised bone allograft and ProOsteon bone substitute: an experimental study in dogs

    DEFF Research Database (Denmark)

    Baad-Hansen, Thomas Einer; Overgaard, S; Lind, M;

    2007-01-01

    weeks osteogenic protein-1 increased bone formation and the energy absorption of implants grafted with allograft and ProOsteon. A composite of allograft, ProOsteon and osteogenic protein-1 was comparable, but not superior to, allograft used on its own. ProOsteon alone cannot be recommended as a......Impacted bone allograft is often used in revision joint replacement. Hydroxyapatite granules have been suggested as a substitute or to enhance morcellised bone allograft. We hypothesised that adding osteogenic protein-1 to a composite of bone allograft and non-resorbable hydroxyapatite granules...... surrounded by a concentric 3 mm gap. These gaps were randomly allocated to four different procedures in each dog: 1) bone allograft used on its own; 2) ProOsteon used on its own; 3) allograft and ProOsteon used together; or 4) allograft and ProOsteon with the addition of osteogenic protein-1. After three...

  16. Interleukin-8 transcripts in mononuclear cells determine impaired graft function after kidney transplantation

    DEFF Research Database (Denmark)

    Borst, Christoffer; Xia, Shengqiang; Bistrup, Claus;

    2015-01-01

    OBJECTIVE: Interleukin-8 (IL-8) has been associated with ischemia reperfusion injury after renal allograft transplantation. Impaired allograft function may cause major impact on patient morbidity and health care costs. We investigated whether transcript levels in mononuclear cells including IL-8...

  17. Donor dopamine treatment limits pulmonary oedema and inflammation in lung allografts subjected to prolonged hypothermia

    NARCIS (Netherlands)

    Hanusch, Christine; Nowak, Kai; Toerlitz, Patrizia; Gill, Ishar S.; Song, Hui; Rafat, Neysan; Brinkkoetter, Paul T.; Leuvenink, Henri G.; Van Ackern, Klaus C.; Yard, Benito A.; Beck, Grietje C.

    2008-01-01

    Background. Endothelial barrier dysfunction severely compromises organ function after reperfusion. Because dopamine pretreatment improves hypothermia mediated barrier dysfunction, we tested the hypothesis that dopamine treatment of lung allografts positively affects tissue damage associated with hyp

  18. Localization of gallium-67 in the normally functioning allografted kidney: concise communication

    Energy Technology Data Exchange (ETDEWEB)

    Fawwaz, R.A.; Johnson, P.M.

    1979-03-01

    Radiogallium localization in the normally functioning renal allograft is a normal finding in the immediate postoperative period. The intensity of tracer accumulation decreases with time and is no longer demonstrable by the end of the second postoperative month.

  19. Chemokines in Chronic Liver Allograft Dysfunction Pathogenesis and Potential Therapeutic Targets

    Directory of Open Access Journals (Sweden)

    Bin Liu

    2013-01-01

    Full Text Available Despite advances in immunosuppressive drugs, long-term success of liver transplantation is still limited by the development of chronic liver allograft dysfunction. Although the exact pathogenesis of chronic liver allograft dysfunction remains to be established, there is strong evidence that chemokines are involved in organ damage induced by inflammatory and immune responses after liver surgery. Chemokines are a group of low-molecular-weight molecules whose function includes angiogenesis, haematopoiesis, mitogenesis, organ fibrogenesis, tumour growth and metastasis, and participating in the development of the immune system and in inflammatory and immune responses. The purpose of this review is to collect all the research that has been done so far concerning chemokines and the pathogenesis of chronic liver allograft dysfunction and helpfully, to pave the way for designing therapeutic strategies and pharmaceutical agents to ameliorate chronic allograft dysfunction after liver transplantation.

  20. Identification of β2-microglobulin as a urinary biomarker for chronic allograft nephropathy using proteomic methods.

    LENUS (Irish Health Repository)

    Johnston, Olwyn

    2011-08-01

    Chronic allograft nephropathy (CAN) remains the leading cause of renal graft loss after the first year following renal transplantation. This study aimed to identify novel urinary proteomic profiles, which could distinguish and predict CAN in susceptible individuals.

  1. Optimising femoral-head osteochondral allograft transplantation in a preclinical model

    Directory of Open Access Journals (Sweden)

    Brett D. Crist

    2016-04-01

    Conclusion: These data provide initial translational and clinical evidence for large osteochondral allografts as a potential option for functional resurfacing of full-thickness cartilage defects of the femoral head.

  2. Polarised light sheet tomography.

    Science.gov (United States)

    Reidt, Sascha L; O'Brien, Daniel J; Wood, Kenneth; MacDonald, Michael P

    2016-05-16

    The various benefits of light sheet microscopy have made it a widely used modality for capturing three-dimensional images. It is mostly used for fluorescence imaging, but recently another technique called light sheet tomography solely relying on scattering was presented. The method was successfully applied to imaging of plant roots in transparent soil, but is limited when it comes to more turbid samples. This study presents a polarised light sheet tomography system and its advantages when imaging in highly scattering turbid media. The experimental configuration is guided by Monte Carlo radiation transfer methods, which model the propagation of a polarised light sheet in the sample. Images of both reflecting and absorbing phantoms in a complex collagenous matrix were acquired, and the results for different polarisation configurations are compared. Focus scanning methods were then used to reduce noise and produce three-dimensional reconstructions of absorbing targets. PMID:27409945

  3. Global ice sheet modeling

    International Nuclear Information System (INIS)

    The University of Maine conducted this study for Pacific Northwest Laboratory (PNL) as part of a global climate modeling task for site characterization of the potential nuclear waste respository site at Yucca Mountain, NV. The purpose of the study was to develop a global ice sheet dynamics model that will forecast the three-dimensional configuration of global ice sheets for specific climate change scenarios. The objective of the third (final) year of the work was to produce ice sheet data for glaciation scenarios covering the next 100,000 years. This was accomplished using both the map-plane and flowband solutions of our time-dependent, finite-element gridpoint model. The theory and equations used to develop the ice sheet models are presented. Three future scenarios were simulated by the model and results are discussed

  4. 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,...

  5. Automatic design system for a steel sheet pile cellular cofferdam and its evaluation; Koya ita cell shiki kozobutsu no kihon sekkei no jidoka oyobi system no hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Sekine, Y.; Ito, A.; Yokota, H. [Port and Harbour Research Inst., Kanagawa (Japan)

    1995-03-01

    A new design scheme has recently been introduced to a sheet pile cellular cofferdam, which takes the effect of the embedded part of a sheet pile on the structural stability into account. On the basis of the modification of the design way, the automatic design system for this type of structure has been established. Port engineers are able to conduct basic design of a breakwater and a seaward made of the sheet pile cellular cofferdam. Parametric studies have been conducted using this automatic design system. It has been confirmed based on the study that this system provides the reasonable structural sections, embedded length, and so on. Some particular characteristics of this type of structures have also been provided in this present report. 5 refs., 59 figs., 4 tabs.

  6. 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.

  7. Biodiesel Basics (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2014-06-01

    This fact sheet provides a brief introduction to biodiesel, including a discussion of biodiesel blends, which blends are best for which vehicles, where to buy biodiesel, how biodiesel compares to diesel fuel in terms of performance, how biodiesel performs in cold weather, whether biodiesel use will plug vehicle filters, how long-term biodiesel use may affect engines, biodiesel fuel standards, and whether biodiesel burns cleaner than diesel fuel. The fact sheet also dismisses the use of vegetable oil as a motor fuel.

  8. Arthroscopic capsule reconstruction in the hip using iliotibial band allograft.

    Science.gov (United States)

    Trindade, Christiano A C; Sawyer, Gregory A; Fukui, Kiyokazu; Briggs, Karen K; Philippon, Marc J

    2015-02-01

    The hip capsule has been identified as an important static stabilizer of the hip joint. Despite the intrinsic bony stability of the hip socket, the capsule plays a key role in hip stability, particularly at the extremes of motion, and the iliofemoral ligament is the most important stabilizer in extension and external rotation. Patients who do not undergo capsular closure or plication may continue to complain of hip pain and dysfunction postoperatively, likely because of microinstability or muscle invagination into the capsular defect, and high-resolution magnetic resonance imaging or magnetic resonance arthrography will identify the capsular defect. Seen primarily in the revision setting, capsular defects can cause recurrent stress at the chondrolabral junction. An attempt at secondary closure can be challenging because of capsular limb adherence to the surrounding soft tissues. Therefore reconstruction may be the only possible surgical solution for this problem. We describe our new surgical technique for arthroscopic hip capsular reconstruction using iliotibial band allograft.

  9. Arthroscopic capsule reconstruction in the hip using iliotibial band allograft.

    Science.gov (United States)

    Trindade, Christiano A C; Sawyer, Gregory A; Fukui, Kiyokazu; Briggs, Karen K; Philippon, Marc J

    2015-02-01

    The hip capsule has been identified as an important static stabilizer of the hip joint. Despite the intrinsic bony stability of the hip socket, the capsule plays a key role in hip stability, particularly at the extremes of motion, and the iliofemoral ligament is the most important stabilizer in extension and external rotation. Patients who do not undergo capsular closure or plication may continue to complain of hip pain and dysfunction postoperatively, likely because of microinstability or muscle invagination into the capsular defect, and high-resolution magnetic resonance imaging or magnetic resonance arthrography will identify the capsular defect. Seen primarily in the revision setting, capsular defects can cause recurrent stress at the chondrolabral junction. An attempt at secondary closure can be challenging because of capsular limb adherence to the surrounding soft tissues. Therefore reconstruction may be the only possible surgical solution for this problem. We describe our new surgical technique for arthroscopic hip capsular reconstruction using iliotibial band allograft. PMID:25973378

  10. Distal Femur Allograft Selection Using a Spectral Shape Descriptor

    International Nuclear Information System (INIS)

    The automatic selection of bone allografts in a virtual bone databank is an active line of research. This work presents a new approach to solve this problem, based on a recently published image descriptor, called Volumetric Heat Kernel Signature. This descriptor is used to compare the size and shape of three dimensional thresholded computed tomography volumes. This approach is compared to a published method that uses the Iterative Closest Points algorithm to register a segmented search template to different candidates present in the databank. Statistical testing of the agreement between the two methods show that both approaches render similar results in the relevant clinical context. The proposed method avoids incorrect registrations due to local minima and does not require lengthly manual image segmentation and positioning before its use. The new method is conceptually simple and its mathematical basis is sound

  11. Amastigotes forms of Trypanosoma cruzi detected in a renal allograft

    Directory of Open Access Journals (Sweden)

    CARVALHO Maria Fernanda C.

    1997-01-01

    Full Text Available Trypanosoma cruzi, the causative agent of Chagas?disease assumes two distinct forms in vertebrate hosts: circulating trypomastigote and tissular amastigote. This latter form infects predominantly the myocardium, smooth and skeletal muscle, and central nervous system. The present work describes for the first time the detection of amastigote forms of T. cruzi in the renal parenchyma of a kidney graft recipient one month after transplantation. The patient was serologically negative for Chagas?disease and received no blood transfusion prior to transplant. The cadaver donor was from an endemic area for Chagas?disease. The recipient developed the acute form of the disease with detection of amastigote forms of T. cruzi in the renal allograft biopsy and circulating trypomastigote forms. The present report demonstrates that T. cruzi can infect the renal parenchyma. This mode of transmission warrants in endemic areas of Chagas?disease

  12. Editorial Commentary: Iliotibial Band Allograft Shows Promise for Arthroscopic Hip Labral Reconstruction.

    Science.gov (United States)

    Rossi, Michael J

    2016-01-01

    Arthroscopic hip labral reconstruction using iliotibial band allograft in a modified front-to-back technique results in improved outcomes after 2-year follow-up. The authors' reasoning for reconstruction are reminiscent of similar arguments for restoring hoop stresses in knee meniscal surgery. Results are comparable to reported outcomes of labral repair, and allograft is particularly indicated for severe labral damage when repair is not possible. Don't miss the related technical note with video in Arthroscopy Techniques.

  13. Editorial Commentary: Iliotibial Band Allograft Shows Promise for Arthroscopic Hip Labral Reconstruction.

    Science.gov (United States)

    Rossi, Michael J

    2016-01-01

    Arthroscopic hip labral reconstruction using iliotibial band allograft in a modified front-to-back technique results in improved outcomes after 2-year follow-up. The authors' reasoning for reconstruction are reminiscent of similar arguments for restoring hoop stresses in knee meniscal surgery. Results are comparable to reported outcomes of labral repair, and allograft is particularly indicated for severe labral damage when repair is not possible. Don't miss the related technical note with video in Arthroscopy Techniques. PMID:26743407

  14. Processing of gamma irradiated bone allografts for treatment of injuries in a nuclear scenario

    International Nuclear Information System (INIS)

    Bone allografts fill an important void in the surgical practice of orthopaedic surgery, and their use to replace and reconstruct musculoskeletal structures following injury or disease has gained increasing acceptance by orthopaedic surgeons. Serious mechanical injuries in a nuclear scenario involving compression, displacement and missile hit will lead to high incidence of various kinds of bone fractures, spinal injuries and joint injuries apart from lethality, lung damage and eardrum rupture. Bone allografts can be employed for repairing fracture defects, filling in destroyed regions of bone, management of open fractures and joint injuries. Autologous bone grafts, though ideal, have the drawback of secondary surgery for autograft retrieval, complications of infection and donor site morbidity. Bone allografts eliminate additional incision necessary for acquiring an autograft and consequently reduce operating time, blood loss as well as hospital and medical costs. However, disease transmission and bacterial infection in bone allograft transplantation is of significant concern. Sterilization by gamma irradiation is a definitive method for eliminating microorganisms and can prevent life-threatening allograft associated infections. The present study was carried out with the aim of bioburden assessment, radiation sterilization and clinical evaluation of bone allografts processed from femoral heads obtained from living donors. Femoral heads were obtained during surgery at Department of Orthopaedic Surgery, SN Medical College, Jodhpur and processed as freeze-dried bone allografts. Bioburden of bone allografts was found to be in the range of 2.26 to 3.59 log CFU/g. Verification dose for different batches of processing was 7.24±1.27 kGy. Radiological data of processed gamma irradiated bone grafts used in clinical cases of trauma surgery was recorded and has shown successful graft incorporation in allogenic recipients. (author)

  15. Microparticulate Cortical Allograft: An Alternative to Autograft in the Treatment of Osseous Defects

    OpenAIRE

    Temple, H. Thomas; Malinin, Theodore I

    2008-01-01

    Benign bone tumors are commonly diagnosed and treated. Following tumor removal, the defect in the bone can be filled with auto- or allografts, (degradable) bone substitutes or non-degradable polymethylmethacrylate. The ideal substitute for this purpose should provide immediate structural support and readily incorporate into bone over a short period of time. Experimentally, microparticulate allograft has been shown to incorporate quickly in metaphyseal and metadiaphyseal cortico-cancellous def...

  16. Is Duplex-Ultrasound a useful tool in defining rejection episodes in composite tissue allograft transplants?

    Science.gov (United States)

    Loizides, Alexander; Kronberger, Irmgard-Elisabeth; Plaikner, Michaela; Gruber, Hannes

    2015-12-01

    Immunologic reactions in transplanted organs are in more or less all allograft patients detectable: clear parameters exist as e.g. in renal transplants where the clearance power reduces by rejection. On the contrary, in composite tissue allografts clear and objective indicators stating a rejection episode lack. We present the case of a hand-transplanted subject with signs of acute transplant rejection diagnosed by means of Duplex Ultrasound and confirmed by biopsy.

  17. Human Split-Thickness Skin Allograft: Skin Substitute in the Treatment of Burn

    OpenAIRE

    Mahdavi-Mazdeh, M.; Nozary Heshmati, B.; Tavakoli, S. A. H.; Ayaz, M.; F. Azmoudeh Ardalan; M. Momeni

    2013-01-01

    Background: Human skin allograft has been used as wound coverage for a long time; it is one of the most successful and widely used dressings for burn wounds in the world. Objective: To prepare a freeze-dried human split-thickness skin allograft and evaluate its cytotoxicity, the structure and physical properties after processing methods and clinical efficacy in burn patients. Methods: After ensuring tissue safety, we lyophilized human cadaveric partial thickness skin and exposed it to gamma r...

  18. High-Throughput Proteomic Approaches to the Elucidation of Potential Biomarkers of Chronic Allograft Injury (CAI

    Directory of Open Access Journals (Sweden)

    Hilary Cassidy

    2013-09-01

    Full Text Available This review focuses on the role of OMICs technologies, concentrating in particular on proteomics, in biomarker discovery in chronic allograft injury (CAI. CAI is the second most prevalent cause of allograft dysfunction and loss in the first decade post-transplantation, after death with functioning graft (DWFG. The term CAI, sometimes referred to as chronic allograft nephropathy (CAN, describes the deterioration of renal allograft function and structure as a result of immunological processes (chronic antibody-mediated rejection, and other non-immunological factors such as calcineurin inhibitor (CNI induced nephrotoxicity, hypertension and infection. Current methods for assessing allograft function are costly, insensitive and invasive; traditional kidney function measurements such as serum creatinine and glomerular filtration rate (GFR display poor predictive abilities, while the current “gold-standard” involving histological diagnosis with a renal biopsy presents its own inherent risks to the overall health of the allograft. As early as two years post-transplantation, protocol biopsies have shown more than 50% of allograft recipients have mild CAN; ten years post-transplantation more than 50% of the allograft recipients have progressed to severe CAN which is associated with diminishing graft function. Thus, there is a growing medical requirement for minimally invasive biomarkers capable of identifying the early stages of the disease which would allow for timely intervention. Proteomics involves the study of the expression, localization, function and interaction of the proteome. Proteomic technologies may be powerful tools used to identify novel biomarkers which would predict CAI in susceptible individuals. In this paper we will review the use of proteomics in the elucidation of novel predictive biomarkers of CAI in clinical, animal and in vitro studies.

  19. Prospective Comparative Study of ACL Reconstruction Between Using Hamstring Autograft and Soft Tissue Allograft

    OpenAIRE

    Song, Eun Kyoo; Seon, Jong Keun; Kim, Hasung

    2014-01-01

    Objectives: Nowadays, two most commonly used grafts in the anterior cruciate ligament reconstruction are hamstring autograft and soft tissue allograft. Although the short-term clinical outcomes between two grafts were similar, only a few studies reported mid-term clinical outcomes. The purpose of this prospective study was to compare clinical outcomes of ACL reconstruction between using hamstring autograft and soft tissue allograft after mid-term follow-up. Methods: One-hundred sixty-one pati...

  20. Characterization of ionizing radiation effects on human skin allografts

    International Nuclear Information System (INIS)

    The skin has a fundamental role in the viability of the human body. In the cases of extensive wounds, allograft skin provides an alternative to cover temporarily the damaged areas. After donor screening and preservation in glycerol (above 85%), the skin can be stored in the Skin Banks. The glycerol at this concentration has a bacteriostatic effect after certain time of preservation. On the other hand, skin sterilization by ionizing radiation may reduces the quarantine period for transplantation in patients and its safety is considered excellent. The objectives of this work were to establish procedures using two sources of ionizing radiation for sterilization of human skin allograft, and to evaluate the skin after gamma and electron beam irradiation. The analysis of stress-strain intended to verify possible effects of the radiation on the structure of preserved grafts. Skin samples were submitted to doses of 25 kGy and 50 kGy in an irradiator of 60Co and in an electron beam accelerator. Morphology and ultra-structure studies were also accomplished. The samples irradiated with a dose of 25 kGy seemed to maintain the bio mechanic characteristics. The gamma irradiated samples with a dose of 50 kGy and submitted to an electron beam at doses of 25 kGy and 50 kGy presented significant differences in the values of the elasticity modulus, in relation to the control. The analysis of the ultramicrographies revealed modifications in the structure and alterations in the pattern of collagen fibrils periodicity of the irradiated samples. (author)

  1. Factors affecting the long-term renal allograft survival

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; LI Xiao-bei; YIN Hang; YANG Xiao-yong; LIU Hang; REN Liang; HU Xiao-peng; WANG Yong; ZHANG Xiao-dong

    2011-01-01

    Background In the past decades, the one-year graft survival of cadaveric renal allografts has been markedly improved,but their long-term survival has not kept pace. The attrition rate of renal allografts surviving after one year remains almost unchanged. The causes for late graft loss are multiple. The aim of this study was to analyze the predictive factors that impact long-term survival of grafts after kidney transplantation.Methods We retrospectively analyzed 524 kidney transplantation patients who were treated in our hospital between January 1991 and January 2000, including 254 patients who had lived more than 10 years with normal graft function (long survival group), and 270 cases whose renal graft had survived less than 10 years (control group). Specifically, we analyzed 10 factors that may potentially affect graft survival by both univariate and Logistic model multivariate analyses to pinpoint the independent risk factors.Results Univariate analyses showed that no significant differences existed in the age or gender of recipients, dialysis time, lymphotoxin levels, or cold ischemia time between the two groups. However, the ratio of delayed graft function and acute rejection, and the uric acid levels of patients in the long survival group were significantly lower than those in the control group (P <0.01). Furthermore, we found that the concentration of cyclosporin A at one year after transplantation and the histocompatibility antigen match of donor-recipients for patients within the long survival group were significantly higher than those in the control group (P <0.01 ). Furthermore, multivariate analyses showed that these four factors were independent risk factors that impact patient survival.Conclusions The ratios of delayed graft function and acute rejection, the concentration of cyclosporin A at one year after transplantation, and serum uric acid levels are very important factors that affect the long-term survival of renal grafts.

  2. Cyclosporine-induced renal dysfunction in human renal allograft recipients.

    Science.gov (United States)

    Kiberd, B A

    1989-12-01

    Cyclosporine-treated renal allograft recipients frequently suffer CsA-related nephrotoxicity and hypertension. This study demonstrates that glomerular filtration rate is reduced acutely by 13% (P less than 0.02) and renal vascular resistance increased by 30% (P less than 0.05), immediately after patients take their CsA dose. The reduction in GFR is directly related to their trough CsA level (r = 0.82; P less than 0.01). The lower the trough CsA level the greater the fall in GFR after the CsA dose. Plasma renin activity does not increase after the CsA dose (pre-CsA 0.6 +/- 0.2 ng/L/sec vs. post-CsA 0.4 +/- 0.1 ng/L/sec; P = NS), and therefore cannot be responsible for the reduction in renal function. Short-term nifedipine treatment is effective in preventing the acute reduction in GFR (P less than 0.05). This occurred despite no apparent effect of nifedipine in altering trough or post-dose CsA levels. Furthermore nifedipine was effective in lowering both the mean arterial blood pressure (109 mmHg to 94 mmHg; P less than 0.01) and the elevated renal vascular resistance (25% reduction; P less than 0.02) observed in these patients. These results suggest that nifedipine may be a suitable agent for limiting acute CsA nephrotoxicity and for treating CsA-associated hypertension in renal allograft recipients.

  3. 犬牙囊干细胞膜片的构建及生物学特性的研究%Construction of Dental Follicle Stem Cell Sheet and its Biological Characteristics in Beagle Dogs

    Institute of Scientific and Technical Information of China (English)

    黄闯; 宋镜明; 宋扬; 刘佳; 王丽颖; 金作林

    2012-01-01

    Objective: To study the construction of dental follicle stem cell sheet and its biological characteristics in Beagle dogs. Methods: After identification.DFSCs were sub-cultured to construct DFSCs sheet. Cell sheet was investaged by inverted microscope, HE staining and scanning electron microscope (SEM). DFSCs sheets were induced by adipogenesis inducing medium and osteogenic medium for 14 days separately. Oil red staining and Alizarin red staining was applied to examine adipogenic induction and osteogenic induction. Results: DFSCs showed typical spindle shape.. Colony-forming assay results showed about 5.1% DFSCs colony formation. DFSCs were positive for CD29 and CD44, but negative for CD34. MTT manifested the growth and proliferation was good. Cell cycle testing showed: G1=87.1%,G2=5.54%. DFSCs sheets were constructed successfully and its growth in multilayer. It found that DFSCs expanded adequately and extracellular matrix(ECM) was clear and numerous in scanning electron micrescopy.Oil red staining and alizarin red staining both demonstrated positive reactions in DFSCs sheet after induction. Conclusion: It suggested that DFSCs cell sheet may be constructed and has a strong bone-forming ability.%目的:利用犬牙囊干细胞(Dental Follicle Stem Cells,DFSCs)构建细胞膜片并研究其生物学特性.方法:取4至6月龄犬尖牙牙胚,分离培养DFSCs,鉴定.用含抗坏血酸的培养基诱导2周构建细胞膜片,并通过倒置显微镜、HE染色、茜素红染色、油红染色、扫描电镜(SEM)对膜片进行形态学检测,检测成骨、成脂能力.结果:DFSCs于体外被成功分离、纯化、培养,细胞克隆形成率约为5.1%.流式鉴定为CD29+CD44+CD34-,增殖能力及克隆形成能力较强,并能成功构建成细胞膜片.光镜和电镜显示膜片细胞排列紧密,细胞基质分泌多,油红O染色后可见细胞内有大量脂滴形成.(B)茜素红染色后可见大量清晰的钙结节形成.结论:成功构建犬DFSCs膜

  4. Pachymic acid, a novel compound for anti-rejection: effect in rats following cardiac allograft transplantation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Fan; WANG Fei; ZHANG Xue-feng; WANG Bai-chun; LIU Hong-yu; LI Chun-yu; LIU Zong-hong; ZHANG Guo-wei; L(U) Hang; CHI Chao

    2009-01-01

    Background Pachymic acid (PA), a natural triterpenoid, is known to significantly reduce cell proliferation and induce apoptosis in vitro through initiation of mitochondria dysfunction. However, its effect on immune cells and anti-rejection following organ transplantation remains unknown.Methods In this study, we investigated PA as a treatment to control acute rejection occurred in rats which had accepted cardiac transplantation. We measured apoptosis of peripheral blood lymphocyte (PBLs), and CD4~+ lymphocyte, as well as the number of CD4~+ and CD8~+ lymphocytes and the effect of PA on acute rejection in rats 7 days after cardiac transplantation.Results PA treatment might decrease allograft rejection, protect PBLs from apoptosis, and reduce the percentage of CD8~+ lymphocyte. PA neither regulated the number nor the apoptosis rate of CD4~+ lymphocyte.Conclusions Our findings indicated that PA has an anti-apoptotic effect acting on PBLs through a novel mechanism involving stabilization of the PBLs mitochondrial transmembrane potential, an anti-rejection effect in rats after cardiac transplantation and an inhibiting effect to CD8~+ lymphocyte.

  5. Nanoparticle Enhanced MRI Scanning to Detect Cellular Inflammation in Experimental Chronic Renal Allograft Rejection

    Directory of Open Access Journals (Sweden)

    S. R. Alam

    2015-01-01

    Full Text Available Objectives. We investigated whether ultrasmall paramagnetic particles of iron oxide- (USPIO- enhanced magnetic resonance imaging (MRI can detect experimental chronic allograft damage in a murine renal allograft model. Materials and Methods. Two cohorts of mice underwent renal transplantation with either a syngeneic isograft or allograft kidney. MRI scanning was performed prior to and 48 hours after USPIO infusion using T2∗-weighted protocols. R2∗ values were calculated to indicate the degree of USPIO uptake. Native kidneys and skeletal muscle were imaged as reference tissues and renal explants analysed by histology and electron microscopy. Results. R2∗ values in the allograft group were higher compared to the isograft group when indexed to native kidney (median 1.24 (interquartile range: 1.12 to 1.36 versus 0.96 (0.92 to 1.04, P<0.01. R2∗ values were also higher in the allograft transplant when indexed to skeletal muscle (6.24 (5.63 to 13.51 compared to native kidney (2.91 (1.11 to 6.46 P<0.05. Increased R2∗ signal in kidney allograft was associated with macrophage and iron staining on histology. USPIO were identified within tissue resident macrophages on electron microscopy. Conclusion. USPIO-enhanced MRI identifies macrophage.

  6. Impaction grafting with morsellised allograft and tricalcium phosphate-hydroxyapatite: incorporation within ovine metaphyseal bone defects.

    Science.gov (United States)

    Pratt, J N J; Griffon, D J; Dunlop, D G; Smith, N; Howie, C R

    2002-08-01

    An ovine model was used to investigate the in vivo properties of impacted tricalcium phosphate-hydroxyapatite (TCP-HA) aggregates, varying in chemical composition (ratio of TCP to HA) and particle size distribution (8 versus 3 particle size ranges). All pellets were impacted to a standard compactive effort. Eight sheep underwent implantation of pellets in 4 metaphyseal defects in both rear limbs. Treatment groups consisted of: (1) allograft (clinical control). (2) 50/50 allograft/80% HA/20% TCP in 8 particle size ranges, (3) 50/50 allograft/80% TCP/20% HA in 8 sizes and (4) 50/50 allograft/80% HA/20% TCP in only 3 sizes of particles. Healing of defects was evaluated at 14 weeks with computed tomography, histology and histomorphometry. The computer tomography (CT) density measured in all defects containing synthetic agents was higher than in defects filled with allograft alone (p<0.01). Defects containing 8 sizes of 80% HA/ 20% TCP granules (group 2) achieved lower histological scores and contained less bone than the clinical control (p<0.05), whereas groups 3 and 4 did not differ from the control. Although all synthetic agents were osteoconductive, our results suggest that increasing the ratio of TCP over HA and limiting the number of particle size ranges to 3 instead of 8 improve the performance of impacted aggregates as graft expanders. Evaluation under loading conditions of morsellised allograft expanded with 80% TCP/20% HA (BoneSave) in 3 particle size ranges is warranted.

  7. Interplay between immune responses to HLA and non-HLA self-antigens in allograft rejection.

    Science.gov (United States)

    Angaswamy, Nataraju; Tiriveedhi, Venkataswarup; Sarma, Nayan J; Subramanian, Vijay; Klein, Christina; Wellen, Jason; Shenoy, Surendra; Chapman, William C; Mohanakumar, T

    2013-11-01

    Recent studies strongly suggest an increasing role for immune responses against self-antigens (Ags) which are not encoded by the major histocompatibility complex in the immunopathogenesis of allograft rejection. Although, improved surgical techniques coupled with improved methods to detect and avoid sensitization against donor human leukocyte antigen (HLA) have improved the immediate and short term function of transplanted organs. However, acute and chronic rejection still remains a vexing problem for the long term function of the transplanted organ. Immediately following organ transplantation, several factors both immune and non immune mechanisms lead to the development of local inflammatory milieu which sets the stage for allograft rejection. Traditionally, development of antibodies (Abs) against mismatched donor HLA have been implicated in the development of Ab mediated rejection. However, recent studies from our laboratory and others have demonstrated that development of humoral and cellular immune responses against non-HLA self-Ags may contribute in the pathogenesis of allograft rejection. There are reports demonstrating that immune responses to self-Ags especially Abs to the self-Ags as well as cellular immune responses especially through IL17 has significant pro-fibrotic properties leading to chronic allograft failure. This review summarizes recent studies demonstrating the role for immune responses to self-Ags in allograft immunity leading to rejection as well as present recent evidence suggesting there is interplay between allo- and autoimmunity leading to allograft dysfunction.

  8. Relationship between CGRP level and acute reject reaction in cardiac allograft recipient in rats

    International Nuclear Information System (INIS)

    Objective: To investigate the relationship between the calcitonin gene related peptide (CGRP) and acute reject reaction in the cardiac allograft in rat. Methods: There were 28 wistar rats with inbreeding line as donors and SD rats as recipients. Cervical heart allograft model was used. Blood was sampled from the third day after grafting to terminal reject reaction when the acceptors were killed. 32 rats without allograft were regarded as the normal controls. Results: The mean survival time of the experimental group was 7.21±2.36 days. Volume of the allografts was greatly increased with hyperemia and edema. CGRP level in the plasma of experimental rats was 180.18±69.77 ng/L, while the level of control rats was 277.41 ± 79.02 ng/L. The deference was statistically significant (P<0.05). Conclusion: In the acute reject reaction, CGRP level is greatly decreased in the plasma of cardiac allograft recipients. Further studies are therefore needed to investigate the application of CGRP measurement in the prevention and treatment of rejection reaction of cardiac allograft

  9. AA amyloidosis in the renal allograft: a report of two cases and review of the literature.

    Science.gov (United States)

    Rojas, Rebecca; Josephson, Michelle A; Chang, Anthony; Meehan, Shane M

    2012-04-01

    AA amyloidosis is a disorder characterized by the abnormal formation, accumulation and systemic deposition of fibrillary material that frequently involves the kidney. Recurrent AA amyloidosis in the renal allograft has been documented in patients with tuberculosis, familial Mediterranean fever, ankylosing spondylitis, chronic pyelonephritis and rheumatoid arthritis. De novo AA amyloidosis is rarely described. We report two cases of AA amyloidosis in the renal allograft. Our first case is a 47-year-old male with a history of ankylosing spondylitis who developed end-stage renal disease reportedly from tubulointerstitial nephritis from non-steroidal anti-inflammatory agent use. A biopsy was never performed. One year after transplantation, AA amyloidosis was identified in the femoral head and 8 years post-transplantation, AA amyloidosis was identified in the renal allograft. He was treated with colchicine and adalimumab and has stable renal function at 1 year-follow-up. Our second case is a 57-year-old male with a long history of intravenous drug use and hepatitis C infection who developed end-stage kidney disease due to AA amyloidosis. Our second patient's course was complicated by renal adenovirus, pulmonary aspergillosis and hepatitis C with AA amyloidosis subsequently being identified in the allograft 2.5 years post-transplantation. Renal allograft function remains stable 4-years post-transplantation. These reports describe clinical and pathologic features of two cases of AA amyloidosis presenting with proteinuria and focal involvement of the renal allograft.

  10. Robot automated EMPT sheet welding

    OpenAIRE

    Pasquale, Pablo; Schäfer, Ralph

    2012-01-01

    Many industrial applications require sheet to sheet or sheet to tube joints. The electromagnetic pulse technology is capable to produce these kinds of joints. In literature many examples of sheet to sheet solid state welding between similar and dissimilar metals are presented and analyzed in detail. However, the most of the presented welding applications, which are very focussed on the academic level, are simple specimens for example for tensile test. These specimens are usuall...

  11. Case report: parenchymal pseudoaneurysm of a renal allograft after core needle biopsy: a rare cause of allograft injury.</