Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Bone Marrow Purging”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 919 records · Page 51Linked to original sources

Ex vivo treatment of bone marrow with phosphorothioate oligonucleotide OL(1)p53 for autologous transplantation in acute myelogenous leukemia and myelodysplastic syndrome.

Effective ex vivo purging techniques can decrease the likelihood of infusing bone marrow contaminated with leukemic cells during autologous transplantation. In preliminary studies, OL(1)p53, a 20-mer phosphorothioate oligonucleotide directed against p53 mRNA, decreased the number of acute myelogenous leukemia (AML) cells in vitro, suggesting a possible role for OL(1)p53 in purging bone marrow harvests of leukemia cells. To demonstrate that OL(1)p53 was nontoxic to hematopoietic progenitor cells, normal bone marrow cells were incubated with 10 microM OL(1)p53 for 36 h, and hematopoietic progenitor cell survival was determined by in vitro colony assays. OL(1)p53 had no toxic effect on the growth of either myeloid (CFU-GM) or erythroid (BFU-E) progenitor cells. OL(1)p53 was then used to ex vivo purge bone marrow harvests from nine patients with either AML or myelodysplastic syndrome (MDS). Bone marrow cells were incubated with 10 microM OL(1)p53 for 36 h before transplantation. The median times posttransplantation for the patient to recover an absolute neutrophil count greater than 0.5 x 10(9)/L and a platelet transfusion independence were 30 days and 56 days, respectively. Incubation of bone marrow cells with OL(1)p53 had no detrimental effect on the growth of hematopoietic progenitor cells, and transplantation of autologous bone marrow cells treated with the phosphorothioate oligonucleotide, OL(1)p53, resulted in successful recovery of circulating neutrophils following high-dose therapy in patients with AML or MDS. The data show that OL(1)p53 can be used safely to purge autologous bone marrow harvests from patients with leukemia.

Adult↗

Effect of pharmacological purging on natural killer cell number and activity in human bone marrow.

We assayed natural killer (NK) cell activity and phenotype from human bone marrow (BM) following "purge" with 4-hydroperoxycyclophosphamide (4HC) at 60 micrograms/ml for 30 min in vitro. In all cases studied, lytic activity against the K562 cell line was either significantly decreased or abolished following 4HC purge. Although NK activity was significantly affected by 4HC treatment, no major differences in the phenotype between the purged and unpurged population were seen. Further, while in vitro culture of BM with IL2 resulted in a significant increment of NK activity, no IL-2 responsive cells were found in the 4HC purged BM after 14 days of culture. This study demonstrates that pharmacological purging of bone marrow results in a persistent functional decline of NK cell activity and may serve as a useful model for the study of the ontogeny of NK cells.

Bone Marrow↗

The effect of a combined purging with mafosfamide and hyperthermia on murine haemopoietic stem cells and leukaemogenic cells.

The in vitro purging effect of mafosfamide combined with hyperthermia was studied in a murine model. The survival of normal clonogenic progenitors (d-9 CFU-S and CFU-GM) and WEHI 3-B leukaemic clonogenic cells (CFU-L) were compared. At 37 degrees C, CFU-L proved to be significantly more sensitive to mafosfamide than either of the normal progenitors. When mafosfamide was combined with 42.5 degrees C hyperthermia for 1 h, an additive effect was observed: at a dose of 5 micrograms/ml mafosfamide, the survival of CFU-L was nearly two logs lower than that observed at 37 degrees C, while 37.7% of CFU-S survived the purging. The repopulating capacity of surviving bone marrow CFU-S was not altered: a similar 60 d survival of supralethally irradiated recipients transplanted with comparable graft sizes from purged or non-purged bone marrow was observed. When bone marrow suspensions containing WEHI 3-B cells were purged with 5 micrograms/ml mafosfamide at 42.5 degrees C and the minimal amount of bone marrow cells needed to protect supralethally irradiated mice were injected, leukaemia incidence was reduced to less than 10% as opposed to 100% of those injected with untreated bone marrow. Our results suggest that ex vivo hyperthermia may enhance the purging efficiency of mafosfamide.

Animals↗

Monoclonal antibodies and magnetic microspheres for the depletion of leukaemic cells from bone marrow harvested for autologous transplantation.

The use of a panel of monoclonal antibodies and anti-mouse immunoglobulin-coated microspheres is described for the depletion of leukaemic blasts from bone marrow. Marrow treated in this way rapidly reconstitutes haemopoietic function after high-dose consolidation chemoradiotherapy. The recovery of cells from bone marrow is similar but not identical to results obtained on removal of neuroblasts from marrow to be used for autologous transplant. This is probably a reflection of the cross-reactivity of 'anti-leukaemic' antibodies with a variety of haemopoietic progenitor cells. The study described here demonstrates the feasibility of using this method to purge leukaemic cells from bone marrow. A much larger randomised study between patients receiving either purged or non-purged bone marrow would be necessary to validate the need to remove small numbers of tumour cells from bone marrow.

Antibodies, Monoclonal↗

In vivo effects of GM-CSF and IL-3 on hematopoietic cell recovery in bone marrow and blood after autologous transplantation with mafosfamide-purged marrow in lymphoid malignancies.

This retrospective study evaluates the impact of GM-CSF and interleukin 3 (IL-3) on bone marrow (BM) and peripheral blood (PB) cell recovery following autologous bone marrow transplantation (ABMT) with mafosfamide-purged BM in patients with lymphoid malignancies compared with a control group receiving no colony-stimulating factor. GM-CSF was administered at 250 micrograms/m2/day (8 patients) as a continuous infusion from day of autologous BMT until the absolute neutrophil count (ANC) reached 0.5 x 10(9)/l for 7 days or until day 30, whichever was first. IL-3 was administered daily starting on the first day of transplant at a dose of 1 microgram/kg/day (6 patients) and 5 micrograms/kg/day (6 patients) for 30 days. CFU-GM and BFU-E were sequentially evaluated in BM and PB at days 7, 14, 21, 28, and 56 post-graft. The neutrophil recovery (ANC > 0.5 x 10(9)/l) was significantly faster in the GM-CSF group compared with IL-3 5 micrograms, IL-3 1 microgram and control group (respectively, days 15, 21, 22, 24) (p < 0.05 to p < 0.01). Similarly, leukocyte recovery was faster in the GM-CSF group compared with control and IL-3 1 microgram groups (p < 0.01 and p < 0.05). No difference was noticed between the two IL-3 groups. Although no difference was observed in platelet recoveries (> 50 x 10(9)/l), it appeared that the GM-CSF group required more units of platelets than either the IL-3 1 microgram or 5 micrograms groups (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Autologous bone marrow transplantation with negative immunomagnetic purging for aggressive B-cell non-Hodgkin's lymphoma in first complete remission.

To evaluate the effect on survival of negative immunomagnetic purging in aggressive B-cell non-Hodgkin's lymphoma (NHL), 20 patients retrospectively staged according to the age-adjusted International Prognostic Index as high-intermediate (11 patients) or high-risk (9 patients) received autologous bone marrow transplantation (ABMT) in first complete remission (CR1). All patients received six to eight cycles of a F-MACHOP-like protocol as induction treatment and then underwent high-dose chemotherapy (HDC) with a CBV-like regimen. Negative purging included a panel of monoclonal antibodies against B-cell antigens and immunomagnetic beads. The data were compared to a historical control of 18 patients with the same characteristics treated in our institution who received unpurged bone marrow support. The median yield of mononuclear cells (MNC), colony-forming units-granulocyte/macrophage (CFU-GM), and CD34+ cells after purging were 52%, 49%, and 57%, respectively. The median B-cell depletion after negative selection was 1.8 logs. All patients obtained a complete engraftment with no significant differences between the purged and unpurged group. Two toxic deaths (one for each group) were observed and the main extrahematological toxicities were mucositis, vomiting, and diarrhea. The event-free survival (EFS) and overall survival (OS) at 3 years for the whole group of 38 patients were 73% (95% CI: 59-88%) and 81% (95% CI, 68-94%), respectively. The comparison between patients receiving purged marrow and patients receiving unmanipulated marrow indicated no significant survival differences between the two groups both for EFS 84% (95% CI: 67-100%) vs 61% (95%CI: 39-84%) ( P=0.12) and OS 84% (95% CI: 69-100%) vs 71% (95% CI: 50-93%) ( P=0.58). Our report shows that HDC followed by reinfusion of autologous bone marrow can produce long EFS and OS in high-intermediate and high-risk patients with B-cell NHL transplanted in CR1, but was not be able to demonstrate a significant clinical advantage using immunomagnetic purged marrow. However, the use of ex vivo negative purging combined with innovative treatment modalities (peripheral blood stem cell transplant, in vivo administration of monoclonal antibodies) needs to be explored.

Adolescent↗

NK inhibitory-receptor blockade for purging of leukemia: effects on hematopoietic reconstitution.

One of the obstacles of BMT that limits its efficacy is failure to eradicate the original tumor. The incidence of tumor relapse is particularly high after autologous BMT. Natural killer (NK) cells comprise various subsets that can express inhibitory receptors for MHC class I determinants. We have recently demonstrated that blockade of NK-cell inhibitory receptors can augment antitumor effects in vitro and in vivo. However, breakdown of tolerance and autoreactivity may occur as a result of the inhibition of NK-cell inactivation to self MHC determinants. We have utilized F(ab')2 fragments of monoclonal antibody, 5E6, against Ly49C/I inhibitory receptors, which are expressed on 35% to 60% of NK cells in H2b strains of mice and are specific for H2Kb, to investigate the effect of inhibitory-receptor blockade on syngeneic bone marrow cell (BMC) and tumor cell growth. We show that treatment of interleukin 2-activated C57BL/6 (B6, H2b) SCID-mouse NK cells with 5E6 F(ab')2 fragments during 48-hour coculture resulted in autoreactivity against syngeneic BMCs as demonstrated by suppression of myeloid reconstitution on day 14 post-BMT. However, this suppressive effect was transient and normalized by day 21 post-BMT. In contrast, blockade of inhibitory receptors during 24-hour coculture had no adverse effects on myeloid reconstitution after BMT. Furthermore, under the same coculture conditions, NK cell-mediated purging of C1498 leukemia cells contaminating syngeneic BMCs was more effective with inhibitory-receptor blockade, leading to a significantly higher proportion of animals with long-term survival compared to the control recipients. These results demonstrate that short-term in vitro blockade of inhibitory receptors can augment antitumor activity without long-term inhibitory effects on BMCs and thus may be of potential use in the purging of contaminating tumor cells prior to autologous BMT.

Animals↗

Cell cycle-based purging of lymphoma cells from bone marrow harvests using radioiodinated 5-iodo-2'-deoxyuridine.

Minimal residual disease in lymphoma patients is a major problem in the clinical management of their cancer. High-dose chemotherapy followed by autologous bone marrow transplantation has been used to treat the disease. However, residual lymphoma may be reintroduced along with the marrow if it is present in the bone marrow harvest. In this report we describe results of experiments testing the efficacy of 5-[125I]-iodo-2'-deoxyuridine (125IdU) for purging murine RAW117 large cell lymphoma cells (Joshi et al., Oncology 44, 180-185, 1987; Cancer Res. 47, 3551-3557, 1987) from bone marrow in a relevant animal model. Donor BALB/c mice were injected with murine RAW117 cells and euthanized on day 13, and their bone marrow that had been contaminated with tumor cells was harvested and treated in vitro with 125IdU or nonradioactive 127IdU (control). Nine of 10 mice receiving 127IdU-treated bone marrow contaminated with tumor cells died at an average of 17 days after injection. In comparison, 9 of 10 mice injected with 125IdU-treated bone marrow contaminated with tumor cells were still alive after 82 days. In addition, the 125IdU treatment did not diminish the formation of hematopoietic progenitor cell colonies in normal mouse and human peripheral blood stem cells.

Animals↗

Purging in autologous hematopoietic stem cell transplantation using adenosine triphosphate (ATP) and 4-hydroperoxycyclophosphamide (4-HC).

In this study, we show potent in vitro purging induced by adenosine triphosphate (ATP) for leukemic cells. The treatment of murine L1210 leukemic cells with 2mM of ATP in vitro for 3h was able to reduce the number of leukemic clonogenic cells by about one order of magnitude presumably by changing the permeability of the leukemic cell membrane. Furthermore, the incubation of L1210 cells with ATP (2mM) and low dose 4-hydroperoxycyclophosphamide (4-HC, 2 microg/ml) for 3h resulted in at least a four-log reduction of clonogenic L1210 cells. Only a slight degree of toxicity to pluripotent hematopoietic stem cells (CFU-S) was observed in both treatment protocols. To determine the efficacy of pharmacological purging by ATP, we designed a murine system to mimic the conditions expected in the clinical setting of autologous transplantation using simulated partial remission marrow (SPRM) which was prepared by mixing normal marrow cells and L1210 cells at a ratio of 9:1. After the SPRM cells were incubated in vitro at a concentration of 1 x 10(6)/ml with both ATP (2mM) and low dose 4-HC (2 microg/ml) for 3h, 5 x 10(4) of the cells were then injected into lethally irradiated 9 weeks male BDF1 mice. All the mice given untreated-SPRM died of leukemia by day 27, whereas none of the recipients transplanted treated-grafts had died by day 70, thus suggesting that the combination use of ATP and 4-HC may be a potentially effective way to purge leukemic cells in autologous stem cell transplantation. The mechanism of the selective killing of leukemic cells is assumed that 4-HC is effectively incorporated into leukemic cells by increasing the permeability of the cell membrane by ATP. Taken together, this simple and rapid procedure is able to purge leukemic cells from autologous bone marrow grafts.

Adenosine Triphosphate↗

Usefulness of lymphokine-activated killer cells generated from bone marrow mononuclear cells for the purging of residual tumor cells in peripheral blood stem cell graft.

Lymphokine-activated killer (LAK) cells were generated from bone marrow mononuclear cells (BM), and the usefulness of the BM-LAK for purging of residual tumor cells in autologous peripheral blood stem cell (PBSC) graft was determined. The BM and peripheral blood lymphocytes (PBL) were obtained from the same bone marrow donors. The BM-LAK and PBL-LAK were generated by incubation with interleukin-2 for 7 days. The BM-LAK demonstrated higher killer activity against a lymphoma cell line Raji than the PBL-LAK. The BM-LAK also had a higher percentage of CD4-CD8-CD16+ cells than the PBL-LAK, which suggests that their high killer activity is related to these cells. The BM-LAK did not show any killer activity against the PBSC graft. However, they killed tumor cells which contaminated the PBSC graft, and in particular, killed chimeric bcr/abl messenger RNA-positive residual leukemic cells. These results suggest that the BM-LAK may be applicable for purging. As the BM-LAK possess higher killer activity than the PBL-LAK, they may be more useful than the PBL-LAK.

Base Sequence↗

Long-term results of high-dose chemotherapy and autologous stem cell rescue for high-risk neuroblastoma patients: a report of the Spanish working party for BMT in children (Getmon).

The authors retrospectively analyzed the long-term outcome of 67 patients over 1 year of age at diagnosis with high-risk neuroblastoma (stage 4 or stage 3 with N-myc amplification) who were treated with megatherapy and stem cell rescue from 1984 to 1998. Median age at transplant was 4 years (range 1.6-15 years). The source of cells was peripheral stem cells in 29 and bone marrow in 38 patients. In 12 patients, an in vitro purging of bone marrow harvest was performed. Most patients were conditioned with melphalan, BCNU, and VM-26. After transplant 19 patients received complementary treatment with IL-2 (16) or 13-cis-retinoic acid (3). Six patients (8%) died from transplant-related toxicity and 39 from disease progression. Three patients were alive with active disease at the time of analysis. Nineteen patients are alive and disease-free at a median follow-up of 104 months. Five-year event-free survival is 0.30. Survival of patients who received a purged graft was not significantly better than the rest. Post-transplant complementary treatment significantly improved overall and event-free survival (p = .01 and p = .04, respectively).

Adolescent↗

A combined approach for purging multidrug-resistant leukemic cell lines in bone marrow using a monoclonal antibody and chemotherapy.

Selective removal of malignant cells (purging) from bone marrow (BM) is a concern in autologous BM transplantation (ABMT). Use of vincristine, etoposide, or doxorubicin for purging could be rendered ineffective by the presence of multidrug-resistant (MDR) tumor cells. To circumvent this particular problem, we investigated whether 17F9, a monoclonal IgG2b antibody directed against the cell surface product of the MDR gene, P-glycoprotein, is effective in selective removal of MDR cells from BM when used with rabbit complement (C'). Using two different cell lines we have demonstrated that 17F9 + C' selectively lyses MDR-positive cells. Three rounds of antibody + C' resulted in 96.4% +/- 3.6% kill of K562/DOX and 100% +/- 0% of CEM/VLB cells. Mixtures of malignant cells and normal BM resulted in 99.85% removal of K562/DOX and 99.91% removal of CEM/VLB clonogenic cells. This treatment did not affect normal committed precursors compared with C' alone. The addition of the cytotoxic agent etoposide (VP-16) following antibody purging results in a 4.6 log reduction of malignant cells. Furthermore, this antibody was effective when used against patients' leukemic blasts. These results suggest the use of 17F9 + C' is effective and selective for removal of MDR cells from BM before ABMT and the addition of VP-16 enhances the purging efficacy.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

A proposal for the addition of hyperthermia to treatment regimens for acute and chronic leukemia.

The application of hyperthermia to the treatment of neoplastic disease has focused on solid tumors. Human leukemias, both acute and chronic, may represent a unique category of diseases for which hyperthermia should be used in combination with other modalities with curative intent. Three clinical approaches to include hyperthermia are proposed. These are hyperthermia in combination with therapeutic low-dose whole-body irradiation, ablative high-dose total body irradiation, and bone marrow transplantation with the in vitro use of hyperthermia to purge remission bone marrow of abnormal cells. Current preclinical research further supporting these clinical applications of hyperthermia to leukemia therapy is presented.

Animals↗

ASTA-Z 7557 impairs human natural killer (NK) cell activity.

Mafosfamide (ASTA-Z 7557) is a chemotherapeutic agent currently used for purging human bone marrow cells prior to autologous bone marrow transplantation. Adoptive cell-mediated immunotherapy has been shown to have a positive effect on the control of minimal residual disease and reinduction of remission post-bone marrow transplantation. Large granular lymphocytes and natural killer (NK) cells are believed to play a role in this effect. In the present work, we assessed the effect of ASTA-Z on the cytotoxic and proliferative capabilities of large granular lymphocytes (LGLs). The ASTA-Z significantly inhibited peripheral blood and bone marrow-derived LGL proliferation and cytotoxic capabilities, while this effect was less pronounced post-IL-2 treatment. We conclude that ASTA-Z purging may significantly impair the NK cell-mediated graft versus leukemia effect and therefore should be preceded by IL-2 therapy.

Antineoplastic Agents↗

The use of long-term bone marrow cultures (LTBMC) to detect hematotoxic side effects of purging methods.

With a view to the establishment of purging methods it is necessary to investigate complete-remission bone marrow as the real target of purging, rather than bone marrow from healthy donors. The results of LTBMC are superior to those of GM-CFC where the hematopoietic recovery of bone marrow is concerned. One-stage LTBMC after bone marrow manipulations may reflect mixed hematopoietic/stromal effects. The use of two-stage LTBMC allows the evaluation of the stem cell recovery without the possible influence of a damaged microenvironment.

Bone Marrow↗

Autologous bone marrow transplantation in childhood acute lymphoid leukemia with use of purging.

INTRODUCTION: Chemotherapy alone is rarely curative for children with recurrent acute lymphoid leukemia (ALL). Although allogeneic bone marrow transplantation has been reported to provide disease-free survival rates of from 40 to 70%, its application is severely limited by the lack of sibling donors. The use of autologous bone marrow transplantation (ABMT) allows the application of therapy of comparable intensity to a larger number of patients. A potential problem associated with transplanting autologous marrow, the reinfusion of residual leukemic cells in the harvested marrow, can be addressed through purging. The most widely used purging techniques involve either immunologic or pharmacologic techniques. PATIENTS AND METHODS: Since 1980, the Dana-Farber Cancer Institute has had an active autologous bone marrow transplantation program for children with recurrent ALL. Sixty-six children underwent autologous marrow transplants with a conditioning regimen consisting of teniposide, cytarabine, cyclophosphamide, and total body irradiation. This was followed by infusion of autologous marrow purged with two monoclonal antibodies directed against CD9 and CD10 and complement. RESULTS: Twelve patients died of acute complications, 26 experienced relapse of ALL, one patient had acute myeloid leukemia 6 years after marrow transplant, and 27 remain in continuous complete remission. The event-free survival rate was 47% for patients with a first remission of at least 2 years, as compared with a rate of 10% for those with a shorter first remission. Since 1989, we have used a new conditioning regimen consisting of fractionated total body irradiation followed by high-dose etoposide and cyclophosphamide for patients with a short first remission. For the first 11 patients, the event-free survival rate is 61%. LITERATURE REVIEW: We reviewed reports of 552 patients with ALL who underwent ABMT at 17 centers. To our knowledge, only four series, including our own, were limited to pediatric patients. Some form of purging was used in 483 (87%) patients. Although conditioning regimens varied greatly, more than 80% of patients received at least total body irradiation and cyclophosphamide. Failure of engraftment was reported in only three patients. The rates of disease-free survival in these series clustered between 25-35%. The most common cause of treatment failure after ABMT was relapse, which occurred in 40-85% of patients. Early deaths from toxicity occurred in 5-21% of patients. Two studies attempted to compare the results of allogeneic and autologous bone marrow transplantation by using the same conditioning regimen for all. Neither series reported significant differences in overall survival.

Bone Marrow Purging↗

Negative selection and protection of normal progenitor cells for autografting.

Autologous bone marrow transplantation (ABMT) after high-dose chemotherapy is recognized as a curative approach to treating hematologic malignancies and some invasive solid tumors. However, tumor cells present in the bone marrow at the time of harvesting are a potential cause for relapse. Ex vivo marrow purging with very high doses of cytotoxic agents has been introduced in an attempt to remove neoplastic cells contaminating the autograft. The procedure, however, has been limited by its high toxicity to normal bone marrow progenitor cells. In their purging procedures, investigators have used agents such as amifostine, originally developed to protect against the effects of radiation and chemotherapy. In this article, the appropriateness of protecting normal cells with amifostine during various purging procedures will be reviewed.

Bone Marrow Cells↗

Clonogenic leukemic progenitor cells in acute myelocytic leukemia are highly sensitive to cryopreservation: possible purging effect for autologous bone marrow transplantation.

The intrinsic AML-CFU sensitivity to cryopreservation was investigated. We compared the recovery of AML-CFU with six different freezing techniques in five myelocytic leukemic (AML) patients to the recovery of normal progenitors (CFU-GM and BFU-E) from control marrows. The recovery for AML-CFU (9.3% +/- 3.1, SE) was significantly lower (p less than 0.001) than for normal CFU-GM (48.4% +/- 4.6) and BFU-E (46.2% +/- 5.0). Moreover, the cloning efficiency of frozen AML-CFU was significantly reduced in 4/5 cases (p less than 0.001), as compared to fresh samples, while it was unaltered in 3/4 normal controls. There were no significant differences between the six freezing techniques, indicating that they are equally efficient for normal progenitors and inefficient for leukemic progenitors. These results indicate that human leukemic progenitors are more sensitive to cryopreservation than normal CFU-GM and BFU-E. These findings suggest that cryopreservation per se may have a purging effect in the context of autologous bone marrow transplantation for acute myelocytic leukemia in complete remission.

Bone Marrow Transplantation↗