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Allogeneic bone marrow transplant is not better than autologous transplant for patients with relapsed Hodgkin's disease. European Group for Blood and Bone Marrow Transplantation.

PURPOSE: To compare the results achieved with myeloablative therapy followed by either allogeneic bone marrow transplantation (alloBMT) or autologous bone marrow transplantation (ABMT) for patients with Hodgkin's disease (HD). PATIENTS AND METHODS: Of more than 1,200 patients with HD reported to the European Bone Marrow Transplantation (EBMT) registry, 49 underwent alloBMT. Of these, 45 with sufficient data were matched to 45 patients who underwent ABMT. The matching criteria were sex, age at time of transplantation, stage of disease at diagnosis, bone marrow involvement at diagnosis and at transplantation, year of transplantation, disease status at time of transplantation, time from diagnosis to transplantation, and conditioning regimen with or without total-body irradiation (TBI). RESULTS: The 4-year actuarial probabilities of survival, progression-free survival (PFS), relapse, and non-relapse mortality were 25%, 15%, 61%, and 48% and 37%, 24%, 61%, and 27% after alloBMT and ABMT, respectively. The toxic death rate at 4 years was significantly higher for alloBMT patients (P = .04). For patients with sensitive disease at the time of transplantation, the 4-year actuarial probability of survival was 30% after alloBMT and 64% after ABMT (P = .007). This difference is mainly due to a higher transplant-related mortality rate after alloBMT (65% v 12%, P = .005). Acute graft-versus-host disease (aGVHD) > or = grade II was associated with a significantly lower risk of relapse, but also with a lower overall survival (OS) rate. CONCLUSION: Based on this study, alloBMT from a human leukocyte antigen (HLA)-identical sibling donor does not appear to offer any advantage when compared with ABMT. A graft-versus-Hodgkin effect is associated with > or = grade II aGVHD, but its positive effect on relapse is largely offset by its toxicity. In most circumstances, alloBMT cannot be recommended for patients with HD.

Adolescent↗

Enhanced histopathology of the bone marrow.

Changes in bone marrow cellularity can be an indicator of systemic toxicity and, therefore, bone marrow should be included in the battery of tissues examined for enhanced histopathology. However, the majority of changes in the bone marrow that are observed in toxicology studies are a response to hematological changes or lesions elsewhere in the body. For this reason, a consideration of all tissue changes in the body is required in order to differentiate toxic effects versus physiological responses in the bone marrow. While enhanced histopathology involves evaluation of the separate compartments in each lymphoid organ using descriptive rather than interpretive terminology, bone marrow is unique in that it lacks specific compartments. Furthermore, identification of erythroid, myeloid, megakaryocytic, and stromal cells, plus adipose tissue and hemosiderin-laden macrophages, can be accomplished from conventional H&E-stained sections, but conclusive identification of lymphoid lineage cells is not likely. This limits the extent of initial enhanced histopathology on bone marrow and argues for the use of cytological preparations for more comprehensive assessment of potential immunomodulatory effects.

Animals↗

Comparison of two different time interval protocols for central venous catheter dressing in bone marrow transplant patients: results of a randomized, multicenter study. The Italian Nurse Bone Marrow Transplant Group (GITMO).

BACKGROUND AND OBJECTIVE: Care of central venous catheter (CVC) in patients undergoing bone marrow transplantation (BMT) raises significant problems related to the high risk of local infections due to the immunodeficient status, which in itself is a predisposing factor for systemic blood-stream infections. Although frequent changes of CVC dressing might theoretically reduce the incidence of infections, they are also accompanied by significant skin toxicity and patient discomfort. No study has yet addressed these points. The objective of this study was to compare two different time interval protocols for CVC dressing in order to assess the effects on local infections and toxicity. DESIGN AND METHODS: In a multicenter study, 399 bone marrow transplant (BMT) patients with a tunneled CVC (Group A, 230 pts) or a non-tunneled one (Group B, 169 pts) were randomly allocated to receive CVC dressing changes every 5 or 10 days, if belonging to Group A, or 2 or 5 days, if in Group B. Transparent, impermeable polyurethane dressings were used for all patients. The rate of local infections at the site of CVC insertion was assessed by microbiological assays every 10 days, while the severity of skin toxicity was measured according to the ECOG scale. RESULTS: Sixty-five per cent of enrolled patients were finally evaluable. Patients (in both Groups) receiving CVC dressing changes at longer intervals did not show a significant increase in the rate of local infections, while those who received dressing every 2 days had a significant increase in local skin toxicity. Longer intervals were accompanied by a reduction in costs. INTERPRETATION AND CONCLUSIONS: The results of this study demonstrate that the increase in time interval between CVC dressing changes in BMT patients did not raise the risk of local infections, while significantly reducing patient discomfort and costs.

Bone Marrow Transplantation↗

Allogeneic bone marrow transplantation using stem cells fractionated by lectins: VI, in vitro analysis of human and monkey bone marrow cells fractionated by sheep red blood cells and soybean agglutinin.

A procedure was developed for the isolation from human bone marrow of a cell fraction enriched for haematopoietic precursors and depleted of T lymphocytes. T cells are eliminated from bone marrow by rosetting with sheep red blood cells, followed by differential agglutination of residual T lymphocytes in the non-rosetting population by the lectin, soybean agglutinin. The fraction unagglutinated by the lectin contains a high proportion of colony-forming cells and non detectable T cell alloreactivity in vitro. Similar results were obtained with monkey bone-marrow cells, suggesting that monkeys can be used for evaluation of this fractionation technique for bone-marrow transplantation across histocompatibility barriers.

Animals↗

T-cell subpopulations in the bone marrow and spleen from thymectomized, irradiated mice reconstituted with normal or nude bone marrow cells.

Adult thymectomized and lethally irradiated (ATxXB) BALB/c mice, reconstituted with either nude or normal bone marrow (BM) cells, have been studied to evaluate numbers and mitogen responsiveness of T cells and T-cell progenitors in the BM and the spleen. Although mice reconstituted with nu/nu cells contained significantly higher numbers of Thy 1.2-positive cells in the BM than mice reconstituted with normal BM cells, smaller in vitro mitogen responses were generally given by the former mice. However, spleen and BM cells of both groups responded to phytohaemagglutinin and to concanavalin A. On the basis of comparisons with responses of BM and spleen cells from normal and ATx mice, anti-Thy 1.2 treatment of cells, and 1 g velocity sedimentation experiments, it is suggested that most mitogen responders in the BM of ATxXB mice are Thy 1.2-negative, pre-thymic T-cell precursors and, accordingly, that these cells are able to differentiate to some extent in the absence of the thymus.

Animals↗

Haemopoietic stem cell concentration and CFUs in DNA synthesis in bone marrow from different bone regions.

The concentration of colony-forming cells (CFUs) is about 40% less in sternal marrow than in the marrow of lumbar vertebrae and femora. Marrow of trabecular bones in lumbar vertebrae contains fewer mitotically active CFUs than marrow of trabecular bones in the femoral distal epiphysis and metaphysis, or the peripheral marrow near the cortical bone in the femoral diaphysis. Only a minor part of the variability of the results in the CFU-assay is due to differences in CUF-concentrations between individual donor mice; pooling of the cell suspensions does not substantially decrease variability. Specific pathogen-free mice yield the same results as BALB/c mice from conventional breeding.

Animals↗

Total body irradiation causes profound changes in endothelial traffic molecules for hematopoietic progenitor cell recruitment to bone marrow.

Nonirradiated bone marrow (BM) venules and sinusoids in murine skull support hematopoietic progenitor cell (HPC) rolling through constitutively expressed endothelial (P- and E-) selectins and VCAM-1. Using intravital microscopy, we tested whether host conditioning with total body irradiation (TBI) changes the molecular mechanisms by which murine HPCs from fetal livers (FL) interact with BM endothelial cells. Although a high dose of TBI did not affect the overall frequency of HPC rolling in BM microvessels, the underlying molecular mechanisms differed from those in nonirradiated BM. TBI induced VCAM-1 up-regulation in BM microvessels, whereas P-selectin expression was reduced and the low baseline level of E-selectin remained unchanged. Only the administration of anti-VCAM-1, but not anti-P- or -E-selectin monoclonal antibodies, decreased FL HPC rolling. Rolling was frequently followed by firm arrest (sticking), even in nonirradiated BM microvessels in which sticking was entirely pertussis toxin-insensitive-that is, Galpha(i)-coupled signaling events (eg, through chemokines) were apparently not required. TBI increased the frequency of sticking FL HPC. This irradiation-induced additional sticking was reversed when FL HPCs were pretreated with pertussis toxin, suggesting that TBI induced elevated expression of a Galpha(i)-protein-coupled chemotactic signal in the BM. This chemoattractant was probably distinct from SDF-1alpha because, unlike adult HPCs, FL HPCs (day 11 of gestation) responded poorly to SDF-1alpha in vitro. These results demonstrate that TBI induces profound changes in the expression of endothelial traffic molecules in the BM, and they indicate that FL HPCs can home to the BM in the absence of SDF-1alpha and other Galpha(i)-protein-coupled signals.

Animals↗

Evaluation of myelotoxicity in cotton rats (Sigmodon hispidus) exposed to environmental contaminants. I. In vitro bone-marrow progenitor culture.

Bone marrow is extremely sensitive to toxicants, and in vitro culture of bone-marrow progenitor cells has been shown to be a sensitive indicator of bone-marrow injury in laboratory rodents. The ability of a bone-marrow progenitor cell assay to detect myelotoxicity in a wild rodent model (cotton rat, Sigmodon hispidus) that inhabits many contaminated ecosystems in the southern United States was examined. Responsiveness of progenitor cells to recombinant murine granulocyte-macrophage colony-stimulating factor (GM-CSF) and cotton rat lung-conditioned medium (LCM) was determined to optimize culture conditions for cotton rats. Myelotoxicity was induced in cotton rats by treating animals with either cyclophosphamide (8 or 80 mg/kg) or dexamethasone (500 microg/kg) over a 5-d period. Administration of a high dose of cyclophosphamide caused nearly total suppression of colony formation of granulocyte-macrophage progenitor cells (CFU-GM). Marked histological changes in both the bone marrow and spleen were also observed in cotton rats treated with a high dose of cyclophosphamide. Although histological lesions were not apparent, the number of CFU-GM in the bone marrow of low-dose cyclophosphamide- and dexamethasone-treated cotton rats was significantly suppressed compared to controls. The number of CFU-GM was consistently higher using LCM than recombinant murine GM-CSF. This reproducible, quantitative, in vitro bone-marrow progenitor cell culture system was a sensitive indicator of myelotoxicity in wild cotton rats and should be useful for monitoring chronic exposures to low levels of environmental toxicants in wild rodent populations.

Analysis of Variance↗

Animal models for acquired bone marrow failure syndromes.

Bone marrow failure is a disease characterized by a drastic decline in the marrow's functional ability to produce mature blood cells. Aplastic anemia, a disease in which patients have essentially empty bone marrow accompanied by severe anemia, neutropenia, and thrombocytopenia, presents a paradigm for bone marrow failure. Damage to the marrow may first result from exposure to toxic chemicals, drug overdose, radiation, and viral infection; however, it is the extended immune-mediated reaction that causes massive destruction of hematopoietic cells and leads to marrow hypoplasia and peripheral pancytopenia. In recent years, animal models of acquired bone marrow failure syndromes have helped to strengthen our understanding of the mechanisms causing bone marrow failure. In this review, animal models for bone marrow failure are summarized by two groups: 1) bone marrow failure induced by toxic chemicals and drugs such as benzene, busulfan, and chloramphenicol, and radiation, and 2) models developed by an immune-related mechanism such as viral infection or foreign lymphocyte infusion.

Anemia, Aplastic↗

Pathology of experimental pulmonary bone marrow embolism. II. Post-embolic pulmonary arteriosclerosis and pulmonary hypertension in rabbits receiving an intravenous infusion of allogeneic bone marrow.

The author investigated the morphogenesis of pulmonary arteriosclerosis in rabbits at 2 days to 3 months after the infusion of sliced fresh allogeneic bone marrow (500 mg) into the marginal ear vein of 87 rabbits. After 2 to 7 days, granulation tissue was formed in the embolized bone marrow, and new endothelial cells appeared on the surface resulting in recanalization. By 2 weeks, embolized bone marrow developed into fibrous and fibro-fatty plaques in the arterial wall. Moreover, from 4 weeks on, smooth muscle cells and elastic fibers proliferated in the emboli just beneath the new endothelial lining. The intima of non-embolized small arteries showed circumferential fibroelastosis, as the result of arteritis and followed by proliferation of medial smooth muscle cells, with narrowing of vascular lumen. The medial smooth muscle cells play an important role in the morphogenesis of pulmonary arteriosclerosis in bone marrow embolism. Pulmonary arterial pressure gradually increased 1 month as well as 3 months after the infusion. It is considered that narrowing of the vascular lumen resulted from post-embolic pulmonary arteriosclerosis may produce persistent pulmonary hypertension.

Animals↗

Bone marrow and recombinant human bone morphogenetic protein-2 in osseous repair.

Bone marrow stem cells and recombinant human bone morphogenetic protein-2 each has the capacity to repair osseous defects. Recombinant human bone morphogenetic proteins require the presence of progenitor cells to function. It is hypothesized that a composite graft of recombinant human bone morphogenetic protein-2 and marrow would be synergistic and could result in superior grafting to autogenous bone graft. Syngeneic Lewis rats with a 5-mm critical sized femoral defect were grafted with recombinant human bone morphogenetic protein-2 and marrow, recombinant human bone morphogenetic protein-2, marrow, syngeneic cancellous bone graft, or carrier alone (control). Serial radiographs (3, 6, 9, 12 weeks) and torque testing (12 weeks) were performed. Bone formation and union were determined. The recombinant human bone morphogenetic protein-2 and marrow composite grafts achieved 100% union at 6 weeks. Recombinant human bone morphogenetic protein alone achieved 80% union by week 12. Both groups yielded a higher union rate and superior mechanical properties than did either syngeneic bone graft (38%) or marrow (47%) alone. The superior performance of recombinant human bone morphogenetic protein-2 combined with bone marrow in comparison with each component alone strongly supports a biologic synergism. This experimentation shows the clinical importance of establishing operative site proximity for the osteoinductive factors and responding progenitor cells.

Animals↗

Clinical application of bone marrow implantation in patients with arteriosclerosis obliterans, and the association between efficacy and the number of implanted bone marrow cells.

BACKGROUND: There have been a number of recent reports on the use of autologous bone marrow implantation (BMI) in the treatment of peripheral arterial disease, with a clinical response rate of approximately 70%. However, the factors that influence efficacy have not yet been clarified. We have analyzed the relationship between the number of implanted bone marrow cells and the clinical efficacy of BMI. METHODS AND RESULTS: Eight patients with arteriosclerosis obliterans were treated with BMI. Bone marrow was aspirated from the ilium (500-1,000 ml), the mononuclear cells were separated and then were implanted. The clinical effectiveness of BMI was evaluated by assessing changes in the ankle-brachial pressure index (ABI) and the transcutaneous oxygen pressure (TcO2) between the pre-treatment baseline, with follow-up testing at 4 weeks. These changes were defined as DeltaABI and DeltaTcO2. The mean number of CD34-positive cells was 1.04+/-0.60 x10(6) /kg body weight. There was a strong correlation between the number of CD34-positive cells and DeltaABI (r=0.754, p=0.028). CONCLUSIONS: It is likely that the number of implanted CD34-positive cells is one of the primary factors that influence the clinical efficacy of BMI.

Aged↗

Prevention of graft-versus-host disease and bone marrow rejection: kinetics of induction of tolerance by UVB modulation of accessory cells and T cells in the bone marrow inoculum.

UVB irradiation (700 J/m2) of bone marrow cells (UVB-BMC) before transplantation into lethally gamma-irradiated (10.5 Gy) allogeneic rats prevents graft-versus-host disease (GVHD) and induces a stable complete lymphohematopoietic chimerism. To better understand the underlying mechanism of the development of stable chimerism and induction of tolerance to donor organs in this model, we examined if the addition of T cells or dendritic cells (DC), as antigen presenting cells (APC), would restore the immunogenicity of UVB-BMC in in vitro mixed lymphocyte reaction (MLR) and induce in vivo bone marrow (BM) graft rejection. Whereas gamma-irradiated, unfractionated BMC induce allogeneic T cells to proliferate, UVB irradiation of BMC abolishes the stimulatory capacity of such cells in a primary MLR. Addition of purified T cells, CD4+ T cells, CD8+ T cells or B cells, respectively, failed to restore the capacity of UVB-BMC to stimulate allogeneic T-cell proliferation. In contrast, the addition of only a small number of splenic accessory cells or purified DC, which by themselves were relatively ineffective in stimulating T-cell proliferation, restored the accessory function and the allostimulatory capacity of UVB-BMC. To define the molecular defect induced by UVB irradiation, cytokines were added as costimulatory factors to primary MLRs and the results showed that the addition of interleukin (IL)-2 or IL-6 but not IL-1 or interferon gamma (IFN-gamma) restored the stimulatory capacity of UVB BMC. This finding suggests that UVB may alter the production, and/or utilization of IL-2 and IL-6 either at the membrane or cytoplasmic level. Parallel in vivo studies showed that addition of DC to UVB BM inoculum resulted in failure of BM engraftment, whereas addition of T cells led to development of fatal GVHD, thus suggesting that UVB modulation of accessory cells reduces graft immunogenicity and prevents BMT rejection, while modulation of T cells prevents GVHD. Our data provide evidence that UVB modulation of APC and mature T cells contained within BMC is potentially useful in preventing GVHD without endangering successful engraftment and may serve as a model for induction of adult chimerism and tolerance without the development of GVHD.

Animals↗

Isolated cilia and crystalloid inclusions in murine bone marrow stromal cells.

Bone marrow stromal cells, especially reticular cells and macrophages, are thought to have important functions in the hematopoietic inductive microenvironment (HIM). In order to define the details of their fine structure, the femoral bone marrow of 50 C 57 BL mice was examined by electron microscopy after fixation by vascular perfusion. Almost all the structures of the murine bone marrow stromal cells were similar to those previously reported. Murine bone marrow reticular cells had some isolated cilia (with a frequency of 6.0%) of 9 + 0 pattern in their axoneme. The murine bone marrow macrophages had crystalloid inclusions (CI) that revealed characteristic periodic substructure. These periodic structures could be classified into four types (types A-D). Type A inclusions had a rather amorphous structure and were the most common (with a frequency of 61.9%). Type B inclusions had a periodic lamellar structure oblique to the long axis of the CI itself at intervals of about 3.5 nm. Type C inclusions had a periodic lattice structure at intervals of about 3.7 nm, and were the least frequent (with a frequency of 6.0%). Type D inclusions had periodic laminated structure parallel to the long axis of CI at intervals of about 3.5 nm. Although the true significance of isolated cilia of murine bone marrow reticular cells and the periodic internal structures of CI in murine bone marrow macrophages remains unknown, they must not be ignored as only incidental findings: they may be useful to the understanding of the relationship between function and structure in future research on HIM.

Animals↗

Graft-versus-host disease prevention in allogeneic bone marrow transplantation from histocompatible siblings. A pilot study using immunotoxins for T cell depletion of donor bone marrow.

Seventeen patients, ages 7-53 years were transplanted with histocompatible bone marrow that had been depleted of T lymphocytes by ex vivo immunotoxin (IT) treatment. Twelve patients had high-risk acute leukemias, and five had chronic myelogenous leukemia. No other graft-vs.-host disease (GVHD) prophylaxis was used. A mixture of three anti-T-cell monoclonal antibodies conjugated to ricin were used in this study: TA-1, UCHT-1 (anti-CD3), and T101 (anti-CD5). The mean number of bone marrow cells infused was 1.5 X 10(8) mononuclear cells/kg recipient weight. Thirteen of the 17 patients demonstrated complete and sustained engraftment. Four patients experienced autologous marrow recovery and/or graft rejection. Compared with an historical group of leukemic patients who received GVHD prophylaxis with methotrexate alone or combinations of methotrexate, and prednisone plus antithymocyte globulin, (ATG) or OKT3, the IT patients with stable engraftment demonstrated shorter time to recovery of leukocytes greater than or equal to 1000mm3 for three consecutive days (median, 20 days vs. 26 days, P = .03). The recovery of total lymphocytes, B and T cell subsets, and T cell function by day 28 was highly variable, but similar, for patients in both the IT-treated group and historical controls. Four patients (ages 13, 18, 21, and 38) developed grade II skin GVHD, but none had severe GVHD. Eight of the 13 patients with durable engraftment have had posttransplant leukemic relapse. Currently only four patients remain alive; two have not relapsed posttransplant, while the other two achieved remission following posttransplant relapse. We conclude that severe GVHD was not observed in this small series with ex vivo T cell depletion for GVHD prophylaxis, and that favorable recovery of hematologic and lymphocytic function was demonstrated for cases where primary engraftment was sustained. A larger randomized controlled study will be needed to establish whether T cell depletion of donor bone marrow with IT can significantly reduce GVHD, and/or improve disease-free survival.

Adolescent↗

Influence of bone marrow on membrane-guided bone regeneration of segmental long-bone defects in rabbits.

Defects 10 mm long were created in long bone in the diaphysis of both radii of 18 rabbits (test and control side). On the test side, ingrowth of bone marrow into the defects was hindered or delayed by: plugging the opening of the cut bone ends with gutta-percha points (n = 7); plugging with Gelfoam (n = 6); or by removing the bone marrow by flushing with saline (n = 5). The defects on both test and control side were covered with an expanded polytetrafluoroethylene membrane, shaped as a tube. Healing was followed with radiographs for four to five months, after which the animals were killed and ground sections of the areas of the defects were prepared for histological examination. On the control side, nine of 18 animals had complete osseous bridging of the defect, and a small transverse non-mineralised zone remained in the centre of the healed defect in the other animals. This zone consisted of loose connective and cartilagenous tissue as well as connective tissue obviously derived from the outside of the membrane. By preventing or delaying the ingrowth of bone marrow we retarded the regeneration of mineralised bone, particularly in the gutta-percha and flushed bone marrow groups. The principle of guided tissue regeneration may be used to achieve regeneration of extensive long-bone defects. Any attempts to delay or prevent bone marrow ingrowth into the defects did retard regeneration of segmental long-bone defects.

Animals↗