40 resultados para stem cell, stem cell therapy, epc, progenitor cell


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The purpose of this investigation was to evaluate the impact of undertaking peripheral blood stem cell transplantation (PBST) on quality of life (QoL), and to determine the effect of participating in a mixed-type, moderate-intensity exercise program on QoL. It was also an objective to determine the relationship between peak aerobic capacity and QoL in PBST patients. QoL was assessed via the CARES questionnaire and peak aerobic capacity by a maximal graded treadmill test, pretransplant (PI), post transplant (PII) and following a 12-week intervention period (PIII). At PII, 12 patients were divided equally into a control or exercise intervention group. Undergoing a PBST was associated with a statistically but not clinically significant decline in QoL (P < 0.05). Following the intervention, exercising patients demonstrated an improved QoL when compared with pretransplant ratings (P < 0.01) and nonexercising transplant patients (P < 0.05). Moreover, peak aerobic capacity and QoL were correlated (P < 0.05). The findings demonstrated that exercise participation following oncology treatment is associated with a reduction in the number and severity of endorsed problems, which in turn leads to improvements in global, physical and psychosocial QoL. Furthermore, a relationship between fitness and QoL exists, with those experiencing higher levels of fitness also demonstrating higher QoL.

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The use of granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood as a source of stem cells has resulted in a high incidence of severe chronic graft-versus-host disease (cGVHD), which compromises the outcome of clinical allogeneic stem cell transplantation. We have studied the effect of G-CSF on both immune complex and fibrotic cGVHD directed to major (DBA/2 --> B6D2F1) or minor (B10.D2 --> BALB/c) histocompatibility antigens. In both models, donor pretreatment with G-CSF reduced cGVHD mortality in association with type 2 differentiation. However, after escalation of the donor T-cell dose, scleroderma occurred in 90% of the recipients of grafts from G-CSF-treated donors. In contrast, only 11% of the recipients of control grafts developed scleroderma, and the severity of hepatic cGVHD was also reduced. Mixing studies confirmed that in the presence of high donor T-cell doses, the severity of scleroderma was determined by the non-T-cell fraction of grafts from G-CSF-treated donors. These data confirm that the induction of cGVHD after donor treatment with G-CSF is dependent on the transfer of large numbers of donor T cells in conjunction with a putatively expanded myeloid lineage, providing a further rationale for the limitation of cell dose in allogeneic stem cell transplantation. (C) 2004 American Society for Blood and Marrow Transplantation.

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Objective. Since 1996, autologous hemopoietic stem cell transplantation (HSCT) has been used to treat severe rheumatoid arthritis (RA). To date, published reports have been individual cases or series containing small numbers. This study combined the worldwide experience in a single analysis. Methods. The Autoimmune Disease Databases of the European Group for Blood and Marrow Transplantation (EBMT) and the Autologous Blood and Marrow Transplant Registry (ABMTR) were used to identify patients with RA treated with autologous HSCT. Further information relating to patient and treatment-specific variables was obtained by questionnaire. Results. Seventy-six patients were registered from 15 centers. Seventy-three patients had received autologous HSCT, and in 3 patients hematopoietic stem cells (HSC) were mobilized but not transplanted. Transplanted patients (median age 42 yrs, 74% female, 86% rheumatoid factor positive) had been previously treated with a mean of 5 (range 2-9) disease modifying antirheumatic drugs (DMARD). Significant functional impairment was present, with a median Health Assessment Questionnaire (HAQ) score of 1.4 (range 1.1-2.0) and Steinbrocker score mean 2.39 (SD 0.58). The high dose treatment regimen was cyclophosphamide (CYC) alone in the majority of patients, mostly 200 mg/kg (n = 62). Seven patients received anti-thymocyte globulin (ATG) in addition to CYC, 2 patients busulfan and CYC (BuCYC), and one patient CYC with total body irradiation and ATG. One patient received fludarabine with ATG. Following treatment, one patient received bone marrow but the rest received chemotherapy and/or granulocyte colony-stimulating factor mobilized peripheral blood stem cells. The harvest was unmanipulated in 28 patients, the rest receiving some form of lymphocyte depletion, mostly through CD34+ selection. Median followup was 16 months (range 3-55). Responses were measured using the American College of Rheumatology (ACR) criteria. Forty-nine patients (67%) achieved at least ACR 50% response at some point following transplant. There was a significant reduction in the level of disability measured by the HAQ (p < 0.005). Most patients restarted DMARD within 6 months for persistent or recurrent disease activity, which provided disease control in about half the cases. Response was significantly related to seronegative RA (p = 0.02) but not to duration of disease, number of previous DMARD, presence of HLA-DR4, or removal of lymphocytes from the graft. There was no direct transplant related mortality, although one patient, treated with the BuCYC regimen, died 5 months post-transplant from infection and incidental non-small cell lung cancer. Conclusion. Autologous HSCT is a relatively safe form of salvage treatment in severe, resistant RA. In these open label studies significant responses were achieved in most patients, with over 50% achieving an ACR 50 or more response at 12 months. Although the procedure is not curative, recurrent or persistent disease activity may be subsequently controlled in some patients with DMARD. Clinical trials are necessary to develop this approach inpatients with aggressive disease who have failed conventional treatment including anti-tumor necrosis factor agents.

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Given that an important functional attribute of stem cells in vivo is their ability to sustain tissue regeneration, we set out to establish a simple and easy technique to assess this property from candidate populations of human keratinocyte stem cells in an in vivo setting. Keratinocytes were inoculated into devitalized rat tracheas and transplanted subcutaneously into SCID mice, and the epithelial lining regenerated characterized to establish the validity of this heterotypic model. Furthermore, the rate and quality of epidermal tissue reconstitution obtained from freshly isolated unfractionated vs. keratinocyte stem cell-enriched populations was tested as a function of (a) cell numbers inoculated; and (b) the inclusion of irradiated support keratinocytes and dermal cells. Rapid and sustained epidermal tissue regeneration from small numbers of freshly isolated human keratinocyte stem cells validates the utilization of this simple and reliable model system to assay for enrichment of epidermal tissue-reconstituting cells.

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The number of cells generated by a proliferating stem or precursor cell can be influenced both by proliferation and by the degree of cell death/survival of the progeny generated. In this study, the extent to which cell survival controls progenitor number was examined by comparing the growth characteristics of neurosphere cultures derived from mice lacking genes for the death inducing Bcl-2 homologue Hara Kiri (Hrk), apoptosis-associated protein 1 (Apaf1), or the prosurvival nuclear factor-kappa B (NF kappa B) subunits p65, p50, or c-rel. We found no evidence that Hrk or Apaf1, and by inference the mitochondrial cell death pathway, are involved in regulating the number of neurosphere-derived progeny. However, we identified the p65p50 NF kappa B dimer as being required for the normal growth and expansion of neurosphere cultures. Genetic loss of both p65 and p50 NF kappa B subunits resulted in a reduced number of progeny but an increased proportion of neurons. No effect on cell survival was observed. This suggests that the number and fate of neural progenitor cells are more strongly regulated by cell cycle control than survival. (c) 2005 Wiley-Liss, Inc.

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Throughout the process of development and continuing into adulthood, stem cells function as a reservoir of undifferentiated cell types, whose role is to underpin cell genesis in a variety of tissues and organs. In the adult, they play an essential homeostatic role by replacing differentiated tissue cells "worn off" by physiological turnover or lost to injury or disease. As such, the discovery of such cells in the adult mammalian central nervous system (CNS), an organ traditionally thought to have little or no regenerative capacity, was most unexpected. Nonetheless, by employing a novel serum-free culture system termed the neurosphere assay, Reynolds and Weiss demonstrated the presence of neural stem cells in both the adult (Reynolds and Weiss, 1992) and embryonic mouse brain (Reynolds et al., 1992). Here we describe how to generate, serially passage, and differentiate neurospheres derived from both the developing and adult brain, and provide more technical details that will enable one to achieve reproducible cultures, which can be passaged over an extended period of time.

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Animal models of autoimmune disease and case reports of patients with these diseases who have been involved in bone marrow transplants have provided important data implicating the haemopoietic stem cell in rheumatic disease pathogenesis. Animal and human examples exist for both cure and transfer of rheumatoid arthritis, systemic lupus erythematosus (SLE) and other organ-specific diseases using allogeneic haemopoietic stem cell transplantation. This would suggest that the stem cell in these diseases is abnormal and could be cured by replacement of a normal stem cell although more in vitro data are required in this area. Given the morbidity and increased mortality in some patients with severe autoimmune diseases and the increasing safety of autologous haemopoietic stem cell transplantation (HSCT), pilot studies have been conducted using HSCT in rheumatic diseases. It is still unclear whether an autologous graft will cure these diseases but significant remissions have been obtained which have provided important data for the design of randomized trials of HSCT versus more conventional therapy. Several trials are now open to accrual under the auspices of the European Bone Marrow Transplant Group/European League Against Rheumatism (EBMT/EULAR) registry. Future clinical and laboratory research will need to document the abnormalities of the stem cell of a rheumatic patient because new therapies based on gene therapy or stem cell differentiation could be apllied to these diseases. With increasing safety of allogeneic HSCT it is not unreasonable to predict cure of some rheumatic diseases in the near future.

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Prospective studies have shown rapid engraftment using granulocyte-colony-stimulating factor-mobilized peripheral blood stem cells (G-PBSCs) for allogeneic transplantation, though the risks for graft-versus-host disease (GVHD) may be increased. It was hypothesized that the use of G-CSF to prime bone marrow (GBM) would allow rapid engraftment without increased risk for GVHD compared with G-PBSC. Patients were randomized to receive G-BM or G-PBSCs for allogeneic stem cell transplantation. The study was designed (beta < .8) to detect a difference in the incidence of chronic GVHD of 33% ( < .05). The plan was to recruit 100 patients and to conduct an interim analysis when the 6-month follow-up point was reached for the first 50 patients. Fifty-seven consecutive patients were recruited (G-BM, n = 28; G-PBSC, n = 29). Patients in the G-PBSC group received 3-fold more CD34(+) and 9-fold more CD3(+) cells. Median times to neutrophil (G-BM, 16 days; G-PBSC, 14 days; P < .1) and platelet engraftment (G-BM, 14 days; G-PBSC, 12 days; P < .1) were similar. The use of G-PBSC was associated with steroid refractory acute GVHD (G-BM, 0%; G-PBSC, 32%; P < .001), chronic GVHD (G-BM, 22%; G-PBSC, 80%; P < .02), and prolonged requirement for immunosuppressive therapy (G-BM, 173 days; G-PBSC, 680 days; P < .009). Survival was similar for the 2 groups. Compared with G-PBSC the use of G-BM resulted in comparable engraftment, reduced severity of acute GVHD, and less subsequent chronic GVHD. (Blood. 2001;98:3186-3191) (C) 2001 by The American Society of Hematology.