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 37 records · Page 2Linked to original sources

Improved outcome for high-risk acute myeloid leukemia patients using autologous bone marrow transplantation and monoclonal antibody-purged bone marrow.

We have conducted a 9-year multicenter trial of autologous bone marrow transplantation (ABMT) for acute myeloid leukemia (AML). Remission BM was purged in vitro using monoclonal antibodies (MoAbs; PM-81, AML-2-23) and complement targeting myeloid differentiation antigens (CD15, CD14). In 1988, the preparative regimen changed from 60 mg/kg/d cyclophosphamide x 2 and fractionated total body irradiation (TBI) total dose, 1,200 cGy (Cy/fTBI), to 4 mg/kg/d busulfan x 4 and 60 mg/kg/d Cy x 2 (Bu/Cy2). Recent analysis (October 1, 1993) shows that the Bu/Cy2 regimen along with the same MoAb purging method yields an improved outcome. Seven first complete-remission (CR) (CR1), 45 second- or third-CR (CR2/3), and 11 first-relapse (R1) patients were treated with chemotherapy and TBI or chemotherapy alone followed by ABMT with MoAb-purged BM. Median age at ABMT for those patients in CR 2/3 and R1 patients was 36 years. Twenty-nine CR 2/3 and R1 patients were conditioned with Cy/fTBI, and 27 CR2/3 and R1 patients were conditioned with Bu/CY. Using the Kaplan-Meier method, the CY/fTBI, CR2/3, and R1 patients have a 3-year disease-free survival (DFS) of 21%. On the other hand, the Bu/Cy2, CR2/3, and R1 patients have a 3-year DFS of 48%. Nineteen CR2/3 and R1 patients relapsed post-ABMT. On analysis by conditioning regimen, those treated with Cy/fTBI have a 3-year relapse rate (RR) of 58%, whereas the patients conditioned with Bu/Cy2 have a 39% 3-year RR. Long-term DFS can be achieved in about 50% of patients with advanced remissions and relapsed AML using Bu/Cy2 with MoAb-purged BM.

Adolescent↗

Does in vitro bone marrow purging improve the outcome after autologous bone marrow transplantation?

High-dose therapy with bone marrow rescue is now regarded as an effective treatment for a variety of malignancies. In an attempt to circumvent the scarcity of HLA-matched donors, autologous marrow has been successfully used as the source of cells for hematopoietic reconstitution. There has been considerable controversy as to whether any malignant cells present in the graft could contribute to relapse of disease post-transplant. In this paper we review clinical results obtained by using autologous transplantation and present evidence on how ex vivo tumor purging may contribute to the outcome.

Acute Disease↗

The use of photodynamic therapy in bone marrow purging.

High-dose chemotherapy and autologous bone marrow transplantation are an effective combination for treating a number of malignant disorders. Clinical trials have demonstrated a potential role for this regimen in the management of acute leukemia and non-Hodgkin's lymphoma. Autologous bone marrow transplantation continues to be limited by high relapse rates, as compared with allogeneic bone marrow transplantation. Two factors are thought to account for this observation. First, autologous transplants lack the immunologic "graft-versus-host" advantage of allogeneic transplants. Second, autologous grafts have the possibility of tumor cell contamination. Methods to reduce tumor cell contamination in autografts include exposure to chemical agents or monoclonal antibodies; long-term marrow cultures; and immunologic manipulation, either with immunomagnetic devices or antibody/complement combinations. Photodynamic therapy (PDT) with porfimer sodium (Photofrin; manufactured by Lederle Parenterals, Carolina, Puerto Rico, under license from Quadra Logic Technologies, Inc, Vancouver, British Columbia, Canada) or benzoporphyrin derivative (BPD verteporfin; BPD-MA; BPD-Quadra Logic Technologies, Inc, Vancouver, British Columbia, Canada) may be an effective means of purging bone marrow. The ability of malignant cells to selectively accumulate photosensitizing agents may account for efficacy of PDT in bone marrow purging. The efficacy of porfimer sodium and BPD has been evaluated in cell lines known to express multidrug resistance (MDR), and the results compared with corresponding MDR-negative cell lines. Multidrug resistance-positive cell lines appear relatively resistant to BPD; porfimer sodium remains active. The reason for the differential effect of MDR positivity on the cytotoxicity of porfimer sodium and BPD is unclear, but is believed to be related to the larger size of the porfimer sodium molecule. Clinical trials evaluating PDT in bone marrow transplantation are under way.

Bone Marrow Purging↗

Bone marrow purging with dibutyl phthalate--experimental basis and a preliminary clinical application.

It has been found recently that di-n-butyl phthalate (DBP) possesses a new pharmacological activity in the selective elimination of tumor cells from marrow. In combination with long-term liquid culture of marrow cells in vitro, DBP purged autologous bone marrow transplantation has first been applied to a case of acute myeloid leukemia at the first complete remission with successful reconstitution of hematopoiesis.

Adult↗

Reconstitution of hematopoiesis after bone marrow purging with ricin A chain immunotoxin.

Bone marrow cells from healthy individuals were treated with an antihuman T cell immunotoxin (IT101). The treated marrow cells were cultured for multilineage hematopoietic colonies (CFU-GEMMT) containing various myeloid cell lineages and T lymphocytes, erythroid colonies (BFU-E), and granulocytic colonies (CFU-C). Optimal conditions were defined for the elimination of clonogenic human T leukemic cells artificially admixed with bone marrow cells. Marrow purging with IT101 led to the restoration of hematopoietic colony formation which was abolished in the presence of T leukemic cells. Mixed colonies grown from bone marrow treated with IT101 contained cells that reacted with monoclonal anti-T-cell antibodies. This suggests that pluripotent stem cells are not affected by marrow IT101 purging and may be able to regenerate lymphoid as well as myeloid lineages.

Antibodies, Monoclonal↗

The efficacy of granulocyte colony-stimulating factor following autologous bone marrow transplantation for non-Hodgkin's lymphoma with monoclonal antibody purged bone marrow.

Cloned colony-stimulating factors have been shown to accelerate myeloid recovery following autologous bone marrow transplantation. Studies with granulocyte-macrophage colony-stimulating factor (GM-CSF) have demonstrated efficacy in accelerating neutrophil recovery in patients rescued from myeloablative therapy. In our previous study, however, the subset of patients who received monoclonal antibody and complement purged bone marrow grafts followed by GM-CSF recovered neutrophil counts at the same rate as placebo-treated patients. We have now performed a phase II trial to assess whether granulocyte colony-stimulating factor (G-CSF) results in accelerated engraftment in this group of patients. Twenty-three consecutive patients with recurrent non-Hodgkin's lymphoma received G-CSF (10.5 +/- 1.2 micrograms/kg per day) following myeloablative therapy consisting of etoposide (60 mg/kg), cyclophosphamide (100 mg/kg), and either carmustine (15 mg/kg) or fractionated total body irradiation (1200 cGy). All patients received bone marrow grafts which had been purged with a panel of monoclonal antibodies directed against either B or T cell determinants plus complement. Peripheral blood mononuclear cells (PBMC) were not administered to any of the patients in this study. Twenty-one patients engrafted at a median absolute neutrophil count (ANC) greater than 500/microliters at day 12 and ANC greater than 1000/microliters at day 14. The time to myeloid engraftment was significantly shortened compared to our previous experience with either GM-CSF or placebo following identical preparatory regimens (p < 0.01). G-CSF is capable of accelerating myeloid engraftment in patients receiving monoclonal antibody purged bone marrow grafts following myeloablative therapy when compared to historical control groups treated with placebo or GM-CSF.

Adult↗

Establishment of a reliable experimental procedure for bone marrow purging with mafosfamide (ASTA Z 7557).

Bone marrow purging with cyclophosphamide derivatives (Mafosfamide) requires the establishment of a defined experimental procedure for reliable leukemic cell destruction while sparing normal hematopoietic stem cells to ensure engraftment. We previously defined the granulocyte-macrophage colony-forming unit (CFU-GM) LD95 as being the maximum tolerable dose of drug to use. We now report, in 20 patients with acute non-lymphoblastic leukemia (n = 5), acute lymphoblastic leukemia (n = 5), chronic myelogenous leukemia (n = 5), and non-Hodgkin's lymphoma (n = 5), that the nature of the cells treated (i.e., buffy coat cells or mononuclear cells) significantly influences the accuracy of the LD95 determination, whereas other parameters such as hematocrit or nucleated cell concentration do not. We subsequently define the most reliable experimental procedure for in vitro purging with Mafosfamide: incubation of 2 x 10(7) buffy coat cells/ml with a hematocrit of 5%. We show that the wide individual susceptibility to the drug is not related to any incubation procedure. In a series of 163 patients with hematological malignancies, we confirm the large variation of sensitivity to the drug according to patient susceptibility and diagnosis. These data favor the adjustment of the dose of Mafosfamide on an individual basis, prior to bone marrow purging for autologous bone marrow transplantation.

Bone Marrow↗

PCR-positivity in harvested bone marrow predicts relapse after transplantation with autologous purged bone marrow in children in second remission of precursor B-cell acute leukaemia.

Purging of autologous bone marrow (BM) grafts of children in second remission after a relapse of precursor B acute lymphoblastic leukaemia (ALL) in the BM has been carried out in our laboratory since 1987, initially by complement mediated cell lysis. This protocol was extended by performing an immunorosette depletion before lysis with complement. The aim of the present study was to assess by polymerase chain reaction the presence of residual leukaemic cells in the BM grafts before and after purging. The results were then correlated to clinical outcome. In 24/28 patients a PCR product was obtained by amplification of IgH and/or TcR junctional regions. BM before purging was available for analysis in 13 patients. We found that leukaemic cells could be detected in 8/13 (62%) of these grafts before purging . All these eight patients experienced a relapse, regardless of whether the purging procedure had been successful (defined as achievement of PCR-negativity) or not. In contrast, none of the five patients with PCR-negative grafts before purging relapsed (P = 0.0008). One patient died due to transplant-related toxicity. Of the remaining 23 patients, nine patients received a PCR-positive BM graft after purging. All these nine patients experienced a relapse as compared to 6/14 whose BM was PCR-negative after purging (P = 0.0072). Two of eight PCR-positive BM grafts could be purged to PCR-negativity. Thus, improvements both in treatment of leukaemia and in purging efficacy are still needed.

Adolescent↗

Autologous bone marrow transplantation for acute myelogenous leukemia using 4-hydroperoxycyclophosphamide and VP-16 purged bone marrow.

Thirty adult patients with acute myelogenous leukemia (AML) in remission were treated with hyperfractionated total body irradiation, VP-16, and cyclophosphamide followed by infusion of autologous bone marrow purged with 4-hydroperoxycyclophosphamide and VP-16. Fifteen patients were transplanted in first remission (R1), 13 in second remission (R2), and two in third remission (R3). All patients had hematopoietic engraftment. The median time to achieve a white blood cell count of 1.0 x 10(9)/l and a neutrophil count of 500 x 10(6)/l was 32 days. The median time to achieve an unsupported platelet count of 50 x 10(9)/l was 70 days. There were four transplant-related deaths, all in patients in R2. Ten patients have relapsed, including both patients transplanted in R3. The disease-free survival (DFS) of all patients is 52%, median follow-up not yet reached. Although the number of patients in each group is small and follow-up is limited, there is a trend toward improved actuarial DFS in patients transplanted in R1 compared with patients transplanted in R2 (72 vs 39%; p = 0.081). Use of VP-16 in the conditioning regimen as well as in the purging procedure is feasible in the treatment of patients with AML.

Adult↗

[An experimental study on bone marrow purging in vitro for patients with chronic myelogenous leukemia].

OBJECTIVE: To investigate the effect of IL-2, IFN and bcr-abl AS-ODN on bone marrow purging in vitro for patients with chronic myelogenous leukemia (CML). METHODS: By amplifying in vitro clone forming culture, and purging the bone marrow of 5 CML patients through different combined use of IL-2, IFN and bcr-abl AS-ODN, we compared the effects of 4 combined regimens. RESULTS: It was found that the suppressive effects of the 4th regimen combining IL-2 (800 U/ml), IFN (800 u/ml) and bcr-abl AS-ODN (30 micrograms/ml) on leukemia cell clone forming unit (CFU) were significantly different from the suppressive effects of the other 3 regimens (P < 0.01). With the use of the 4th regimen, the GM-CFU and L-CFU survival rates were 26.91% and 3.49% respectively (P < 0.01). CONCLUSION: The combined regimen of IL-2 (800 U/ml), IFN (800 u/ml) and bcr-abl AS-ODN (30 micrograms/ml) has good effect on selective CML bone marrow purging in vitro and can be used in clinical purging of CML bone marrow.

Bone Marrow Cells↗

Detection of tumor cells in purged bone marrow and peripheral-blood mononuclear cells by polymerase chain reaction amplification of bcl-2 translocations.

PURPOSE: To compare bone marrow (BM) before and after purging with monoclonal antibodies (MAbs) and complement with peripheral-blood mononuclear cells (PBMNCs) for tumor-cell contamination by amplification of t(14;18) sequences using the polymerase chain reaction (PCR). PATIENTS AND METHODS: Sixty patients with non-Hodgkin's lymphoma (NHL) undergoing autologous BM transplantation were evaluated. Six BM biopsies were performed at the time of harvesting and evaluated morphologically for tumor involvement. The harvested BM was treated with a panel of anti-B-cell MAbs directed against CD9, CD10, CD19, and CD20, followed by rabbit complement. Clonogenic assays were performed before and after purging. DNA was extracted and t(14;18) sequences amplified by PCR. PBMNCs collected by apheresis for back-up purposes were similarly evaluated. RESULTS: Fifteen patients (25%) were PCR-positive before BM purging. Following MAb- and complement-mediated purging, there was a reduction in the PCR-amplified signal in 10 patients (67%). There was no reduction in colony-forming unit granulocyte-macrophage (CFU-GM) colony growth following purging. Eight of these 15 patients (53%) had morphologic evidence of BM involvement at the time of harvesting. In these eight patients, only three had a reduction in the PCR-amplified products, as compared with all seven who were morphologically negative at the time of BM harvesting (P = .026). Fourteen of these 15 patients had PBMNCs collected near the time of BM harvesting and 12 (86%) were PCR-positive. CONCLUSION: BM purging with MAbs and complement results in reduction in the number of t(14;18)-positive tumor cells, especially in those patients who have no morphologic evidence of BM disease at the time of harvesting. Purged BM was less contaminated with t(14;18)-positive cells than unpurged PBMNCs, which were frequently contaminated with tumor cells.

Adolescent↗

Engraftment of leukocyte subsets following autologous bone marrow transplantation in acute myeloid leukemia using anti-myeloid (CD14 and CD15) monoclonal antibody-purged bone marrow.

The cell surface phenotype of leukocyte subsets during reconstitution following autologous bone marrow transplantation (ABMT) using bone marrow purged with anti-myeloid monoclonal antibodies (MoAbs) and complement (C') was evaluated in 20 patients with acute myeloid leukemia (AML). Repopulation of B and T lymphocytes, natural killer (NK) cells, and myeloid cells was assessed by phenotypic analysis using two-color cytofluorography of peripheral blood mononuclear cells (PBMNC) at several time points up to 2 years post-transplantation. In spite of removal of the majority of monomyeloid cells of the autograft by purging with anti-CD14 and anti-CD 15, engraftment occurred rapidly. The myeloid cells appeared normal by surface phenotype. An early rise in NK cells, characterized by expression of CD57 and CD 16, was seen. The CD4:CD8 ratio remained low throughout the study period, primarily due to a persistently low CD4 level. ABMT using bone marrow purged with the anti-myeloid MoAbs PM-81 and AML-2-23 and C' resulted in prompt engraftment of neutrophils. Although there was a prolonged time for recovery of lymphocyte subsets, this did not result in an increased risk of early infectious complications. Late infectious complications post-transplantation were limited to herpes zoster infection in one patient 18 months post-transplantation, and bacterial meningitis in that same patient 2 months later. This study demonstrates that ABMT in patients with AML using bone marrow purged with the anti-myeloid MoAbs PM81 (anti-CD15) and AML-2-23 (anti-CD14) and C' results in rapid hematologic engraftment and delayed phenotypic immunologic reconstitution without significant acute or chronic clinical toxicities.

Adolescent↗

Autologous bone marrow transplantation for high risk acute lymphoblastic leukemia: clinical relevance of ex vivo bone marrow purging with monoclonal antibodies and complement.

Herein we describe our experience with 75 consecutive autologous BM transplants for patients with high-risk ALL, with special attention to the clinical impact of BM purging. Fifty-two patients received purged BM using monoclonal antibody (MoAb) cocktails and complement, and 23 patients received untreated BM. The distribution of prognostic factors was similar in both groups. Hemopoietic reconstitution was adequate and did not differ in the two groups. Transplant-related mortality was 9.6% and 13% in 'purged' and 'unpurged' groups. Median follow up was 11 months (2-71) and overall actuarial probability of disease-free survival (DFS) at 5 years was 40% (53% relapse probability). We found a beneficial effect of purging in patients over 15 years of age and in patients needing more than 1 month to reach CR1. Patients in CR1 receiving purged marrow had a longer DFS and a lower relapse probability (52% vs 12%, P = 0.02 and 35% vs 86%, P = 0.005, respectively) which were related to the efficacy of the purging procedure (more or less than one log of depletion). In further CR, no advantage of purging has been found. Our data strongly suggest the clinical relevance of BM purging in autologous BMT in high-risk ALL patients and support the need for prospective randomized studies.

Adult↗

High-dose therapy and autologous peripheral stem cell transplantation for patients with bone marrow metastases and relapsed lymphoma: an alternative to bone marrow purging.

Throughout a 4-year period, we reinfused autologous peripheral stem cells rather than purged autologous bone marrow following high-dose therapy to 57 patients with relapsed lymphoma and bone marrow metastases. Approximately 7 x 10(8) circulating mononuclear cells/kg patient weight were collected for each patient with 6-19 4-h apheresis procedures while hemopoiesis was unperturbed. Following collection, the cells were cryopreserved. Administration of high-dose therapy, which included either combination chemotherapy or combination chemotherapy plus total body irradiation, was followed by i.v. administration of the thawed autologous stem cells. The rate of hemopoietic recovery varied with the specific high-dose therapy administered. Sixty-two percent of 50 evaluable patients had a clinical complete response. The actuarial event-free survival for these patients 4 years after transplantation was 30%, and the projected survival at 4 years was 51%. Patients with relapsed lymphoma and bone marrow metastases who receive high dose therapy followed by peripheral stem cell transplantation can experience long-term event-free survival. Whether similar patients would fare as well with the same high-dose therapy followed by a purged autologous bone marrow transplantation would require a randomized prospective study.

Adult↗

Normal blast colony formation: an in vitro tool for monitoring human bone marrow 'purging'.

A major problem in autologous bone marrow transplantation is that it is impossible to evaluate in vitro the effect of drug treatment on haematopoiesis. However, Gordon and colleagues have recently established a colony forming assay which detects very immature blast progenitor cells. This method can be used to measure the myelotoxicity of drugs used for removing malignant cells from bone marrow ('purging') before autografting and we have analysed the action of mafosfamide on normal blast colony formation. Treatment in vitro with mafosfamide did not impair the formation of blast colonies containing very primitive cells (type I) but suppressed the formation of the colonies of more mature cells (types II and III) which grow under the same culture conditions. The surviving type I blast colony-forming cells were capable of self-renewal and differentiation. In contrast granulocyte-macrophage colony-forming units (GM-CFU) were totally destroyed by treatment with mafosfamide.

Bone Marrow↗