956 resultados para Bone Marrow Transplantation


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Gut was studied as a prototypical mucosal membrane in the murine BDF-1 syngeneic bone marrow transplant model. Measures of jejunal intraepithelial lymphocytes (IELs) and crypt cells were obtained by standard techniques and a method of quantifying gut lamina propria plasma cells (PCs) was developed. The degree of ablation of gut PCs and IELs after 900 rads total body irradiation with ('60)Co, and their repopulation effected by transplantation with 2.0 x 10('5) or 1.0 x 10('6) bone marrow cells demonstrated a prolonged period of profound depression in population levels of these cells which was not reflected by the extent of damage sustained to the epithelium. Differences in the depopulation and recovery of gut PCs and IELs revealed a tendency towards initial differentiation of effector cells. A positive dose response to high bone marrow cell innocula was obtained. Subsequent studies determined that gut IEL and PC repopulation was potentiated by the addition of IELs or buffy coat cells (BCs) to the bone marrow transplant. A method of isolating 1.4 - 4.0 x 10('7) viable IELs per gram of murine small bowel was devised employing intralumenal hyaluronidase digestion of the epithelial layer and centrifugation of the resulting suspension through discontinuous Percoll gradients. Irradiated mice received 2.0 x 10('5) bone marrow cells along with an equal number of IELs or BCs. The extent and duration of depression of numbers of IELs and PCs was markedly reduced by the addition of the IEL isolate to the transplantation innocula, and to a lesser degree by the addition of BCs. The augmentation of repopuation far exceeded that expected by simple lodging of cells suggesting that the additionally transplanted cells contained a subpopulation of mucosal membrane lymphoid stem cells or helper cells. Correlation analysis of PC versus IEL levels suggests a possible feedback mechanism governing the relative size of their populations. Normal ratios of IgA, IgM, and IgG bearing PCs was maintained post transplantation with all of the regimens. ^

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Allogeneic bone marrow transplantation (BMT) is known to induce a beneficial anti-tumor immune response called graft-versus-tumor (GVT) activity. However, GVT activity is closely associated with graft-versus-host disease (GVHD), a potentially fatal immune response against antigens on normal recipient tissues. The T-cell populations mediating these two processes are often overlapping, but studies have shown that some donor T-cells can be tumor-specific. Therefore, the goal of this study was to develop strategies for preferentially activating donor T-cells capable of mediating GVT activity but not GVHD. The three hypotheses tested were: (1) Pre-transplant immunization of BMT donors with a recipient-derived tumor cell vaccine will induce a relative increase in GVT activity as compared to GVHD. (2) Post-transplant tumor immunization of BMT recipients will enhance GVT activity without exacerbating GVHD. (3) Pre-transplant immunization of BMT donors against a tumor-specific antigen will enhance GVT activity without exacerbating GVHD. ^ To test the first two hypotheses, C3H.SW mice (MHC-matched donors) were immunized with a C57BL/6 (recipient)-derived tumor cell vaccine (leukemia or fibrosarcoma) prior to BMT, or recipients were immunized starting one month after BMT. Both donor and recipient immunization led to a significant increase in GVT activity (enhanced recipient survival and decreased tumor growth). However, donor immunization also increased fatal GVHD, which was at least partially due to activation of alloreactive T-cells recognizing the immunodominant minor histocompatibility antigen B6dom1. GVT immunity following recipient immunization was not associated with an exacerbation of GVHD or a response to B6dom1. ^ To test the third hypothesis, influenza nucleoprotein (NP) was used as a model tumor antigen. C3H.SW donors were immunized against NP prior to BMT, which led to a significant increase in GVT activity. Although recipients were not completely protected against growth of antigen loss variant tumors, there was no increase in GVHD. ^ In conclusion, (1) immunization of allogeneic BMT donors with a recipient-derived tumor cell vaccine substantially increases GVT activity but also exacerbates GVHD, (2) post-transplant tumor immunization of allogeneic BMT recipients significantly increases GVT activity and survival without exacerbating GVHD, and (3) immunization of allogeneic BMT donors against a tumor-specific antigen significantly enhances GVT activity without exacerbating GVHD. ^

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The relative merits of PBSCT versus BMT for children with standard and high risk hematologic malignancies remain unclear. In a retrospective single center study, we compared allogeneic peripheral blood stem cell transplantation (PBSCT) (n=30) with bone marrow transplantation (BMT) (n=110) in children with acute leukemia. We studied recipients of HLA matched sibling stem cells, and of stem cells from alternative donors (HLA mismatched and/or unrelated) and determined whether sourcing the stem cells from PB or marrow affected engraftment, incidence of acute and chronic GvHD, and disease-free survival at 1 year. Our results show a modest reduction in time to engraftment from PB stem cells and no greater risk of GvHD, but illustrate that the severity of the underlying disease is by far the greatest determinant of 1 year survival. Patients in the BMT group had a higher treatment success rate and lower costs than the recipients of the PBSCT within the standard but not the high risk disease group, where the treatment success rate and the cumulative costs were lower in the PBSCT group compared to the BMT group. Our current incremental cost-effectiveness ratio and analysis of uncertainty suggest that allogeneic transplantation of bone marrow grafts was a more cost-effective treatment option compared to peripheral blood stem cells in patients with standard risk childhood acute leukemia disease. For high risk disease our data are less prescriptive, since the differences were more limited and the range of costs much larger. Neither option demonstrated a clear advantage from a cost-effectiveness standpoint.^

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Transplantations of fully allogeneic, autoimmune-resistant T-cell-depleted marrow (TCDM) plus syngeneic, autoimmune-prone TCDM into lethally irradiated BXSB mice were carried out to investigate the ability of the mixed bone marrow transplantation (BMT) to prevent development of autoimmune disease and, at the same time, to reconstitute fully the immunity functions of heavily irradiated BXSB recipients. Male BXSB mice were engrafted with mixed TCDM from both allogeneic, autoimmune-resistant BALB/c mice and syngeneic, autoimmune-prone BXSB mice. BMT with mixed TCDM from both resistant and susceptible strains of mice (mixed BMT) prolonged the median life span and inhibited development of glomerulonephritis in BXSB mice. BMT with mixed TCDM also prevented the formation of anti-DNA antibodies that is typically observed in male mice of this strain. Moreover, mixed BMT reconstituted primary antibody production in BXSB recipients, so that no annoying immunodeficiencies that are regularly observed in fully allogeneic chimeras were present in the recipient of the mixed TCDM. These findings indicate that transplanting allogeneic, autoimmune-resistant TCDM plus syngeneic, autoimmune-prone TCDM into lethally irradiated BXSB mice prevents development of autoimmune disease in this strain of mice. In addition, this dual BMT reconstitutes the immunity functions and avoids the immunodeficiencies that occur regularly in fully allogeneic chimeras after total-body irradiation.

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Fabry disease is an X-linked metabolic disorder caused by a deficiency of α-galactosidase A (α-Gal A). The enzyme defect leads to the systemic accumulation of glycosphingolipids with α-galactosyl moieties consisting predominantly of globotriaosylceramide (Gb3). In patients with this disorder, glycolipid deposition in endothelial cells leads to renal failure and cardiac and cerebrovascular disease. Recently, we generated α-Gal A gene knockout mouse lines and described the phenotype of 10-week-old mice. In the present study, we characterize the progression of the disease with aging and explore the effects of bone marrow transplantation (BMT) on the phenotype. Histopathological analysis of α-Gal A −/0 mice revealed subclinical lesions in the Kupffer cells in the liver and macrophages in the skin with no gross lesions in the endothelial cells. Gb3 accumulation and pathological lesions in the affected organs increased with age. Treatment with BMT from the wild-type mice resulted in the clearance of accumulated Gb3 in the liver, spleen, and heart with concomitant elevation of α-Gal A activity. These findings suggest that BMT may have a potential role in the management of patients with Fabry disease.

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Sandhoff disease is a lysosomal storage disorder characterized by the absence of β-hexosaminidase and storage of GM2 ganglioside and related glycolipids in the central nervous system. The glycolipid storage causes severe neurodegeneration through a poorly understood pathogenic mechanism. In symptomatic Sandhoff disease mice, apoptotic neuronal cell death was prominent in the caudal regions of the brain. cDNA microarray analysis to monitor gene expression during neuronal cell death revealed an upregulation of genes related to an inflammatory process dominated by activated microglia. Activated microglial expansion, based on gene expression and histologic analysis, was found to precede massive neuronal death. Extensive microglia activation also was detected in a human case of Sandhoff disease. Bone marrow transplantation of Sandhoff disease mice suppressed both the explosive expansion of activated microglia and the neuronal cell death without detectable decreases in neuronal GM2 ganglioside storage. These results suggest a mechanism of neurodegeneration that includes a vigorous inflammatory response as an important component. Thus, this lysosomal storage disease has parallels to other neurodegenerative disorders, such as Alzheimer's and prion diseases, where inflammatory processes are believed to participate directly in neuronal cell death.

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von Willebrand factor (vWF) is essential for the induction of occlusive thrombosis in stenosed and injured pig arteries and for normal hemostasis. To separate the relative contribution of plasma and platelet vWF to arterial thrombosis, we produced chimeric normal and von Willebrand disease pigs by crossed bone marrow transplantation; von Willebrand disease (vWD) pigs were engrafted with normal pig bone marrow and normal pigs were engrafted with vWD bone marrow. Thrombosis developed in the chimeric normal pigs that showed normal levels of plasma vWF and an absence of platelet vWF; but no thrombosis occurred in the chimeric vWD pigs that demonstrated normal platelet vWF and an absence of plasma vWF. The ear bleeding times of the chimeric pigs were partially corrected by endogenous plasma vWF but not by platelet vWF. Our animal model demonstrated that vWF in the plasma compartment is essential for the development of arterial thrombosis and that it also contributes to the maintenance of bleeding time and hemostasis.

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Host antigen-presenting cells (APCs) are known to be critical for the induction of graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (BMT), but the relative contribution of specific APC subsets remains unclear. We have studied the role of host B cells in GVHD by using B-cell-deficient mu MT mice as BMT recipients in a model of CD4-dependent GVHD to major histocompatlibility complex antigens. We demonstrate that acute GVHD is initially augmented in mu MT recipients relative to wild-type recipients (mortality: 85% vs 44%, P < .01), and this is the result of an increase in donor T-cell proliferation, expansion, and inflammatory cytokine production early after BMT. Recipient B cells were depleted 28-fold at the time of BMT by total body irradiation (TBI) administered 24 hours earlier, and we demonstrate that TBI rapidly induces sustained interleukin-110 (IL-10) generation from B cells but not dendritic cells (DCs) or other cellular populations within the spleen. Finally, recipient mice in which B cells are unable to produce IL-10 due to homologous gene deletion develop more severe acute GVHD than recipient mice in which B cells are wild type. Thus, the induction of IL-10 in host B cells during conditioning attenuates experimental acute GVHD.

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We report the use of an Internet-based videophone to support a child undergoing bone marrow transplantation (BMT). Over the Christmas period, an eight-year-old boy with an underlying diagnosis of attention-deficit/hyperactivity disorder (ADHD) and a history of absconding and aggressive non-compliant behaviour was treated by BMT. We installed an Internet-based videophone in the patient's hospital room two days post-transplant. A second videophone was installed in the patient's home and used the existing home telephone line. In all, 14 videophone calls were made over a nine-day period. The videophone improved interfamily social and emotional support, and appeared to reduce some of the inherent anxiety and distress resulting from paediatric bone marrow transplantation.

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Several reports have shown that the hippocampus plays an important role in different aspects of the emotional control. There is evidence that lesions in this structure cause behavioral disinhibition, with reduction of reactions expressing fear and anxiety. Thus, to portray the aptitude of cell therapy to abrogate injuries of hippocampal tissue, we examined the behavioral effects of bone marrow mononuclear cells (BMMCs) transplantation on C57BL/6 mice that had the hippocampus damaged by electrolytic lesion. For this purpose, mice received, seven days after bilateral electrolytic lesion in the dorsal hippocampus, culture medium or BMMCs expressing the enhanced green fluorescent protein (EGFP) transgene. One week after transplantation, animals were tested in the elevated plus-maze (EPM). On the whole, three assessment sessions in the EPM were carried out, with seven days separating each trial. Thirty-five days after the induction of injury, mice were sacrificed and their brains removed for immunohistochemistry. The behavioral evaluation showed that the hippocampal lesion caused disinhibition, an effect which was slightly lessened, from the second EPM test, in transplanted subjects. On the other hand, immunohistochemical data revealed an insignificant presence of EGFP+ cells inside the brains of injured mice. In view of such scenario, we hypothesized that the subtle rehabilitation of the altered behavior might be a result from a paracrine effect from the transplanted cells. This might have been caused by the release of bioactive factors capable of boosting endogenous recuperative mechanisms for a partial regaining of the hippocampal functions. © 2013 Elsevier B.V.

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Bone marrow transplantation (BMT) is commonly used for the treatment of severe haematological and immunological diseases. For instance, the autoimmune lymphoproliferative syndrome (ALPS) caused by a complete expression defect of CD95 (Fas, APO-1) can be cured by allogeneic BMT. However, since this therapy may not generate satisfactory results when only partially compatible donors are available, we were interested in the development of a potential alternative treatment by using lentiviral gene transfer of a normal copy of CD95 cDNA in hematopoietic stem cells. Here, we show that this approach applied to MRL/lpr mice results in the expression of functional CD95 receptors on the surface of lymphocytes, monocytes, and granulocytes. This suggests that correction of CD95 deficiency can be achieved by gene therapy.

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The Australian Bone Marrow Donor Registry (ABMDR) is a publicly funded company that is part of an international network that facilitates unrelated bone marrow transplantation. This role means that the ABMDR has access to a large biospecimen repository, therefore making it a highly valuable research resource. Recognising the potential value of these biospecimens for research purposes, the ABMDR is in the process of determining whether, and how, to share its biospecimens with other biobanks. While this would undoubtedly be of value to the scientific community, and ultimately to the wider community, it would also inevitably transform the role of an institution whose primary role is therapeutic, and would compromise the degree of control that a custodian has over donated material. This article describe the challenges confronting the ABMDR, and organisations like it, in balancing their duties to donors, patients, researchers and the general public. These problems have led inevitably to the use of "property" rights language in the discussion of these issues but notions of gift, ownership, trusteeship and transfer might also be considered.

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Results of recent studies have indicated that bone marrow cells can differentiate into various cells of ectodermal, mesodermal, and endodermal origins when transplanted into the body. However, the problems associated with those experiments such as the long latent period, rareness of the event, and difficulty in controlling the processes have hampered detailed mechanistic studies. In the present study, we examined the potency of mouse bone marrow cells to differentiate into cells comprising skin tissues using a skin reconstitution assay. Bone marrow cells from adult green fluorescent protein (GFP)-transgenic mice were transplanted in a mixture of embryonic mouse skin cells (17.5 days post-coitus) onto skin defects made on the backs of nude mice. Within 3 weeks, fully differentiated skin with hair was reconstituted. GFP-positive cells were found in the epidermis, hair follicles, sebaceous glands, and dermis. The localization and morphology of the cells, results of immunohistochemistry, and results of specific staining confirmed that the bone marrow cells had differentiated into epidermal keratinocytes, sebaceous gland cells, follicular epithelial cells, dendritic cells, and endothelial cells under the present conditions. These results indicate that this system is suitable for molecular and cellular mechanistic studies on differentiation of stem cells to various epidermal and dermal cells.