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Biomedical subjects

M Cottler-Fox

Publications and source records attributed to M Cottler-Fox.

At least 19 recordsLinked to original sources
PubMed1995

Transfer of the human glucocerebrosidase gene into hematopoietic stem cells of nonablated recipients: successful engraftment and long-term expression of the transgene.

In trying to develop methods of gene therapy for Gaucher disease that will avoid the morbidity and mortality associated with bone marrow (BM) ablation, we transplanted BM stem cells transduced with a retroviral vector containing the human glucocerebrosidase cDNA into normal, nonablated, syngeneic mice. Donor BM from untreated male mice or treated with 5-fluorouracil (5-FU) was transduced ex vivo using a standard 4-day transduction protocol. Recipient female mice were injected one time only or once daily for 5 consecutive days or once a week for 5 consecutive weeks using 2 x 10(7) (untreated BM) or 2 x 10(6) (5-FU-treated BM) cells per injection. Initial transduction efficiency into colony-forming unit-spleen (CFU-S) was 80% to 100%. Recipient analysis was performed at least 6 months after the last transplantation. The best engraftment of donor stem cells, up to 5% by secondary CFU-S analysis, was obtained with multiple injections of transduced BM not previously treated with 5-FU. Polymerase chain reaction (PCR) amplification for both the transgene and the Y chromosome identified the progeny of transduced stem cells in various hematopoietic and non-hematopoietic organs. The copy number of the transgene in stem cells was 0.13 to 2.8. Transgene expression was shown by reverse transcriptase-PCR, in situ hybridization, and immunohistochemistry. No serious side effects of the procedure were noted. We conclude that multiple transplants of retrovirally transduced BM cells into nonablated recipients may be a safe and effective therapeutic modality for a number of genetic hematopoietic disorders.

Animals↗
PubMed1995

Retrovirally marked CD34-enriched peripheral blood and bone marrow cells contribute to long-term engraftment after autologous transplantation.

We report here on a preliminary human autologous transplantation study of retroviral gene transfer to bone marrow (BM) and peripheral blood (PB)-derived CD34-enriched cells. Eleven patients with multiple myeloma or breast cancer had cyclophosphamide and filgrastim-mobilized PB cells CD34-enriched and transduced with a retroviral marking vector containing the neomycin resistance gene, and CD34-enriched BM cells transduced with a second marking vector also containing a neomycin resistance gene. After high-dose conditioning therapy, both transduced cell populations were reinfused and patients were followed over time for the presence of the marker gene and any adverse effects related to the gene-transfer procedure. All 10 evaluable patients had the marker gene detected at the time of engraftment, and 3 of 9 patients had persistence of the marker gene for greater than 18 months posttransplantation. The marker gene was detected in multiple lineages, including granulocytes, T cells, and B cells. The source of the marking was both the transduced PB graft and the BM graft, with a suggestion of better long-term marking originating from the PB graft. The steady-state levels of marking were low, with only 1:1000 to 1:10,000 cells positive. There was no toxicity noted, and patients did not develop detectable replication-competent helper virus at any time posttransplantation. These results suggest that mobilized PB cells may be preferable to BM for gene therapy applications and that progeny of mobilized peripheral blood cells can contribute long-term to engraftment of multiple lineages.

Antigens, CD↗
PubMed1995

Positive selection of CD34+ hematopoietic cells using an immunoaffinity column results in T cell-depletion equivalent to elutriation.

Acute graft-vs.-host disease (GVHD) continues to present a barrier to successful allogeneic marrow transplantation. T cell-depletion may prevent severe GVHD but carries an increased risk of graft rejection and relapse posttransplant. Clinical trials have defined the number of lymphocytes associated with sustained engraftment but low risk of significant GVHD (greater than grade I or II skin only) as < or = 10(5)/kg. We examined T cell-depletion resulting from positive selection of CD34+ hematopoietic cells with a biotinylated monoclonal anti-CD34 antibody and an immunoaffinity column. Eleven patients (six myeloma and five breast cancer) underwent both peripheral blood stem cell (PBSC) collection and marrow harvest prior to autologous transplantation. One PBSC collection and one-third of each marrow underwent column separation. PBSCs were enriched for CD34+ cells from an initial mean of 1.5 to 53.3%, while marrow went from an initial mean of 2.8 to 65.4%. PBSC were depleted of CD3+ cells from an initial mean of 9.6 x 10(9) to 8.6 x 10(6). Marrow CD3+ lymphocyte content was reduced from an initial mean of 5.6 x 10(9) to 8 x 10(5). Since the column permits quantification and salvage of depleted T cells, its use should allow re-addition of T cell-aliquots associated with minimal risk for GVHD and rejection. In addition, since PBSCs were as readily depleted as marrow, allogeneic PBSC transplant may be feasible using this method.

Antigens, CD↗
PubMed1994

The impact of harvest center on quality of marrows collected from unrelated donors.

The total number and distribution of nucleated cells in harvested bone marrow are potentially important determinants of patient outcome following bone marrow transplantation. In order to assess whether marrows collected from predominantly unrelated donors at Georgetown University Medical Center (GUMC) were different in cellular content from marrows collected at harvest centers outside of GUMC, we compared the nucleated cell counts and mononuclear cell subset distribution (CD34, CD3, CD4, CD8, CD19 antigen-positive cell content) of 10 consecutive marrows harvested at GUMC to 10 unrelated donor marrows from outside harvest centers. Significantly higher nucleated cell counts and CD34 antigen-positive cell content and significantly lower CD3 and CD4 antigen-positive T-cell numbers were demonstrated among the marrows harvested at GUMC. These results confirmed significant variability in marrow collection practices between GUMC and 10 different outside harvest centers and suggest that strict adherence to a specific collection procedure, involving small volume marrow aspirations and multiple puncture sites, results in a product with a high number of early hematopoietic progenitor cells and minimal contamination by peripheral blood. These data further suggest the need for careful monitoring of individual unrelated donor marrow collection centers' practices to optimize the quality of the harvested marrow.

Academic Medical Centers↗
PubMed1992

The pathobiology of HIV infection.

The follicular dendritic cells (FDCs) of the germinal center are known to absorb antigens in the form of immune complexes and to express them on the cell surface for long periods of time. Here, Cecil Fox and Michele Cottler-Fox propose that, as a result of FDC binding of immune-complexed viruses, lymphoid organs are the major reservoirs of HIV, and that FDCs play a key role in infection of CD4+ T cells.

Antigen-Antibody Complex↗
PubMed1992

Phase I and II study of high-dose ifosfamide, carboplatin, and etoposide with autologous bone marrow rescue in lymphomas and solid tumors.

PURPOSE: High-dose chemotherapy produces durable disease-free remissions in a minority of patients with resistant lymphomas and solid tumors. In an attempt to improve on the available regimens, ifosfamide, carboplatin, and etoposide (ICE) were selected for a new high-dose regimen because of their favorable spectrum of nonhematopoietic toxicity and evidence of synergy in in vitro systems. PATIENTS AND METHODS: Forty-one patients with drug-resistant Hodgkin's and non-Hodgkin's lymphomas, and breast and testicular cancers were entered onto a phase I and II trial of a single course of ICE with autologous bone marrow rescue. Before transplantation, all patients received combination chemotherapy until maximal tumor response was achieved. RESULTS: Patients received total doses of ifosfamide from 10 to 18 g/m2, carboplatin from 0.9 to 1.98 g/m2, and etoposide from 0.6 to 1.5 g/m2 administered during a 4-day period, with a maximum-tolerated dose (MTD) of ifosfamide 16 g/m2, carboplatin 1.8 g/m2, and etoposide 1.5 g/m2. The dose-limiting toxicities included irreversible renal, cardiac, and CNS dysfunction. There were three toxic deaths (7%), and all occurred above the MTD. Thirteen patients who were treated at the MTD tolerated the regimen well; reversible renal dysfunction and grade 2 mucositis commonly were observed. Of 23 heavily pretreated patients with persistent disease at the time of transplant, 10 (43%) achieved complete remissions (CRs) and 11 (48%) achieved partial remissions (PRs). Hodgkin's and non-Hodgkin's lymphoma patients who were treated at or below the MTD had a median potential follow-up of 11.9 months, and 12-month progression-free survivals of 62% and 48%, respectively. CONCLUSION: High-dose ICE with bone marrow rescue was well tolerated with a high response rate, and should be considered for further testing.

Adult↗
PubMed1991

Some but not all benefits of intravenous immunoglobulin therapy after marrow transplantation appear to correlate with IgG trough levels.

Multiple benefits of intravenous immunoglobulin (IVIG) therapy after marrow transplantation have been reported, including decreased incidence of acute graft-versus-host disease (GVHD), infection, sepsis, cytomegalovirus (CMV) pneumonitis and platelet use. To test the hypothesis that the observed beneficial effects of IVIG are related to the serum IgG levels achieved, we followed IgG levels (pre-infusion, 1 h and 24 h post-infusion) in 45 consecutive marrow transplant recipients. IVIG 500 mg/kg was given weekly for six doses starting day -8 pre-transplant, then every other week for a total of 11 doses. Forty-one patients (22 allogeneic, 17 autologous, two syngeneic) were evaluable. Patients with acute GVHD had significantly lower serum IgG trough levels (less than 1200 mg/dl) noted at day +20 post-transplant and afterwards than patients without GVHD (greater than or equal to 1200 mg/dl). Pharmacokinetic modeling of the data indicates that IgG half-life between day -8 and day +6 may predict which recipients are at increased risk of acute GVHD. Allogeneic recipients in the group with trough levels less than 1200 mg/dl required more platelet transfusions. Although there was no significant difference in fungal infection rates or bacteremia, sepsis was noted in only two recipients (one allogeneic, one autologous), both with serum IgG trough levels less than 1200 mg/dl. In addition, three allogeneic recipients had cytomegalovirus pneumonitis, all in the group with lower IgG trough levels. Thus, while serum IgG trough levels less than 1200 mg/dl appear to be strongly associated with acute GVHD, low levels may also be associated with increased platelet utilization, with cytomegalovirus pneumonitis, and sepsis, but not with the overall incidence of infection.

Adolescent↗
PubMed1991

Conditioning-related toxicity and acute graft-versus-host disease in patients given methotrexate/cyclosporine prophylaxis.

Intensive chemoradiotherapy conditioning regimens and acute graft-versus-host disease (GVHD) are both associated with significant morbidity and mortality after bone marrow transplantation. In this study, we investigated whether the conditioning regimen affected the development of acute GVHD. Thirty-four patients, four with severe aplastic anemia and 30 with a lymphohemopoietic malignancy, were prepared for transplantation either with cyclophosphamide (CY) alone, with CY combined with total body irradiation (TBI) or CY combined with etoposide and either TBI or busulfan. GVHD prophylaxis included methotrexate (MTX 10 mg/m2) given on days 1, 3 and 6, and daily cyclosporine (CSP) on days--1 through 180. The overall incidence of acute GVHD was 36% (15% for HLA identical, 87% for HLA non-identical recipients). However, when assessed by the severity of conditioning regimen-related toxicity, the incidence of GVHD grades II-IV (HLA identical; HLA non-identical) was 0% (0%; 0%), 37% (20%; 67%) and 50% (22%; 100%) for patients with mild, moderate and severe toxicity, respectively. Compliance with GVHD prophylaxis declined with increasing intensity and toxicity of the conditioning regimen. These data suggest that a regimen of three doses of MTX and daily CSP is as effective as four doses of MTX/CSP for GVHD prophylaxis in patients given HLA identical marrow grafts. However, GVHD regimen compliance and efficacy of GVHD prevention are inversely related to the intensity of the conditioning regimen.

Acute Disease↗