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C Hesdorffer

Publications and source records attributed to C Hesdorffer.

At least 19 recordsLinked to original sources
PubMed2006

Allogeneic stem cell transplantation corrects biochemical derangements in MNGIE.

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a multisystemic autosomal recessive disease due to primary thymidine phosphorylase (TP) deficiency. To restore TP activity, we performed reduced intensity allogeneic stem cell transplantations (alloSCTs) in two patients. In the first, alloSCT failed to engraft, but the second achieved mixed donor chimerism, which partially restored buffy coat TP activity and lowered plasma nucleosides. Thus, alloSCT can correct biochemical abnormalities in the blood of patients with MNGIE, but clinical efficacy remains unproven.

Adult↗
PubMed2002

Therapy-related myelodysplastic syndrome after autologous stem cell transplantation for breast cancer.

Therapy-related myelodysplastic syndrome and acute myelogenous leukemia (t-MDS/AML) are serious complications of chemotherapy and radiotherapy for cancer. High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) may be associated with an increased incidence of these complications. The frequency of t-MDS/AML after ASCT for breast cancer is uncertain. We reviewed our database of 379 consecutive breast cancer ASCT patients treated with alkylator-based chemotherapy, followed for a median of 1.52 years (range 0-8.97), with a median survival of 6.16 years. Three patients have developed tMDS/AML. The probability of developing this complication at 5 years is 0.032 in our series. We have used pathologic, cytogenetic and molecular methods to evaluate which portions of therapy may have predisposed to the development of this complication. Cytogenetic abnormalities were not found in the stem cell harvests of these patients by metaphase analysis or by fluorescence in situ hybridization (FISH). One patient demonstrated a clonal X chromosome inactivation pattern in her stem cell harvest, indicating pre-transplant chemotherapy may have been responsible for the development of her leukemia. As two of our patients developed this complication at greater than 4 years post-transplant, the number of cases may increase with longer follow-up. While the incidence appears to be low, further prospective and retrospective analysis will be necessary to determine which portions of therapy predispose to the development of t-MDS/AML in patients undergoing ASCT for treatment of breast cancer.

Acute Disease↗
PubMed1999

Up-regulation of amphotrophic retroviral receptor expression in human peripheral blood CD34+ cells.

Retroviral-mediated gene transfer into hematopoietic stem cells provides the only means of stable transduction of these cells and their progeny for use with a variety of potentially therapeutic genes. Expression of the Moloney amphotropic retroviral receptor-pit-2 or GLVR-2-is critical to the recognition and entry of Moloney leukemia virus-derived viruses into human target cells such as CD34+ hematopoietic cells. GLVR-2 functions as a sodium-dependent phosphate transporter as well as a receptor. We have previously shown that the expression of the murine homologue of the amphotropic receptor Ram 1, also a phosphate transporter, is developmentally regulated in murine hematopoietic fetal liver cells. We also demonstrated that culture of murine fetal liver cells in phosphate-free (PO(4)-free) medium increases levels of receptor mRNA and makes murine fetal liver cells susceptible to Moloney amphotropic viral gene transfer. We now examine the effect of culture conditions on the expression of GLVR-2 in human CD34+ cells. In this report, we demonstrate that there is a 2-3 fold increase in GLVR-2 mRNA levels in CD34+ cells after 3 days in culture with interleukin 3, interleukin 6, and stem-cell factor. In addition, the use of PO(4)-free medium increases expression of GLVR-2 an additional 2-fold in these cells during this time. These results indicate that GLVR-2 expression can be up-regulated on these cells, and may permit improved retroviral gene transfer efficiencies.

Animals↗
PubMed1999

Competitive repopulation of retrovirally transduced haemopoietic stem cells.

Gene transfer into haemopoietic stem cells (HSC) may be useful in gene therapy for a variety of inherited and acquired human diseases. Cell division is required for retroviral transduction, and cytokine stimulation is often used to increase mitosis of quiescent HSC. Exposure to cytokines has been shown to have an unfavourable effect on the engraftment of these cells when competed with unmanipulated HSC. We now show that a similar engraftment defect is present when HSC are manipulated and transduced with the human multiple drug resistance (MDR) gene. The extent of the unfavourable competition depended on the relative numbers of cytokine-treated and fresh cells when the two populations of cells were administered simultaneously into marrow-ablated isogenic mice. When the manipulated transduced cells were given 2 or 4 d before the unmanipulated cells there was a much greater engraftment of the manipulated cells. The data suggested that the manipulated cells were at a relative disadvantage for marrow engraftment as compared to fresh cells, presumably due to the more efficient homing and engraftment properties of these latter unmanipulated cells. However, the manipulated cells had no intrinsic inability to engraft when they were the predominant donor cell population. In all cases the percent of MDR transduced cells in the engrafting manipulated cells remained relatively constant at about 25-30%. These results have implications for the use of manipulated transduced stem cells in gene therapy, suggesting that administering them before adding fresh cells can overcome their engraftment defect.

Animals↗
PubMed1998

Effects of long-term storage at -90 degrees C of bone marrow and PBPC on cell recovery, viability, and clonogenic potential.

Autologous BM and PB HPC are usually stored from weeks to months until reinfusion after myeloablative chemotherapy. HPC have been stored for up to 16 months at -90 degrees C, using a mixture of 5% DMSO, 6% hydroxyethyl starch (HES), and 4% HSA as a cryoprotectant. Long-term storage (LTS) has usually entailed rate-controlled freezing using 10% DMSO and preservation in liquid nitrogen. The effects of LTS at -90 degrees C on the in vitro cell recovery, viability, and colony-forming unit-granulocyte macrophage (CFU-GM) clonogenic potential of autologous HPC that were not transplanted was studied. Sixteen BM and sixteen PB HPC had been cryopreserved for a median of 53 months (range 27-71) and 35 months (range 26-78), respectively. Samples of frozen HPC were thawed after 48 h, and the nucleated cell count, viability by trypan blue exclusion, and culture for CFU-GM were obtained. Following LTS, the cells were thawed and examined using the same assays. No difference in the median percentage recovery of nucleated cells was found in either the BM or PB HPC between the samples stored for 48 h and after LTS (5.73 x 10(9) versus 5.61 x 10(9) and 6.20 x 10(9) versus 5.78 x 10(9), respectively). In addition, no difference in median percentage viability was found in either the BM or PB HPC sampled at 48 h and at the end of LTS (75% versus 74% and 75% versus 76%, respectively). Finally, the median number of CFU-GM cultured from BM HPC at 48 h was 2.41 x 10(5) (range 0.33-11.01 x 10(5)) and at the end of LTS was 1.93 x 10(5) (range 0.32-10.55), representing a median recovery of 93% (range 19%-308%). Similarly, the median number of CFU-GM cultured from PB HPC was 1.66 x 10(5) (range 0-50.57) and at the end of LTS was 0.93 x 10(5) (range 0-44.9), representing a median recovery of 80% (range 36%-165%). This difference in percentage recovery was not significant (p = 0.514). There was poor correlation between the number of nucleated cells harvested and the percentage recovery of nucleated cells, cell viability, or CFU-GM for either the BM or PB HPC. Similarly, there was poor correlation between the number of CFU-GM in the harvest and their percentage recovery following LTS for both BM and PB HPC. Finally, there was poor correlation between the storage time of the BM or PB HPC and the percentage recovery of nucleated cells, cell viability, and CFU-GM. These data suggest that LTS of HPC at -90 degrees C is not associated with decreased recovery of nucleated cells or in vitro viability and is associated with only a modest decrease in clonogenic potential. This indicates that storage of HPC at -90 degrees C for periods in excess of 3 years is possible.

Blood Preservation↗
PubMed1998

Phase I trial of retroviral-mediated transfer of the human MDR1 gene as marrow chemoprotection in patients undergoing high-dose chemotherapy and autologous stem-cell transplantation.

PURPOSE: Normal bone marrow cells have little or no expression of the MDR p-glycoprotein product and, therefore, are particularly susceptible to killing by MDR-sensitive drugs, such as vinca alkaloids, anthracyclines, podophyllins, and paclitaxel and its congeners. Here we report the results of a phase I clinical trial that tested the safety and efficacy of transfer of the human multiple drug resistance (MDR1, MDR) gene into hematopoietic stem cells and progenitors in bone marrow as a means of providing resistance of these cells to the toxic effects of cancer chemotherapy. PATIENTS AND METHODS: Up to one third of the harvested cells of patients who were undergoing autologous bone marrow transplantation as part of a high-dose chemotherapy treatment for advanced cancer were transduced with an MDR cDNA-containing retrovirus; these transduced cells were reinfused together with unmanipulated cells after chemotherapy. RESULTS: High-level MDR transduction of erythroid burst-forming unit (BFU-E) and colony-forming unit-granulocyte macrophage (CFU-GM) derived from transduced CD34+ cells was shown posttransduction and prereinfusion. However, only two of the five patients showed evidence of MDR transduction of their marrow at a low level at 10 weeks and 3 weeks, respectively, posttransplantation. The cytokine-stimulated transduced cells may be out-competed in repopulation by unmanipulated normal cells that are reinfused concomitantly. The MDR retroviral supernatant that was used was shown to be free of replication-competent retrovirus (RCR) before use, and all tests of patients' samples posttransplantation were negative for RCR. In addition, no adverse events with respect to marrow engraftment or other problems related to marrow transplantation were encountered. CONCLUSION: These results indicate the feasibility and safety of bone marrow gene therapy with a potentially therapeutic gene, the MDR gene.

Adult↗
PubMed1998

Phase I trial of sequential high-dose chemotherapy with escalating dose paclitaxel, melphalan, and cyclophosphamide, thiotepa, and carboplatin with peripheral blood progenitor support in women with responding metastatic breast cancer.

A single high-dose cycle of chemotherapy with stem cell support can produce disease-free survival of 15-20% for at least 3 years in women with responding stage IV breast cancer. North American Autologous Bone Marrow Transplant Registry data suggest that a complete response (CR) is the single most important prognostic factor associated with prolonged disease-free survival. Therefore, if sequential high-dose chemotherapy can increase the CR rate, then perhaps an increased proportion of patients will remain disease free. Women with at least a partial response (PR) to induction chemotherapy received three separate high-dose cycles of chemotherapy with peripheral blood progenitor support and granulocyte colony-stimulating factor. The first intensification was a dose escalation of paclitaxel (400-825 mg/ m2), the second intensification was melphalan (180 mg/m2), and the third intensification consisted of 6000 mg/m2 cyclophosphamide (1500 mg/m2/day), 500 mg/m2 thiotepa (125 mg/m2/day), and 800 mg/m2 carboplatin (200 mg/m2/day; CTCb). Thirty-six women were enrolled and 31 completed all three cycles. After the paclitaxel infusion most patients developed reversible predominantly sensory neuropathy. Of the 19 patients with measurable disease, 6 converted to CR, 7 converted to a PR* (the complete resolution of all soft tissue or visceral disease with sclerosis of prior lytic bone lesions), and 2 had a further PR for an overall response rate of 79%. Two patients had no further response and disease in two patients progressed, and thus they were taken off the study before CTCb. Seventy-eight percent are progression-free at a median follow-up of 14 months (range, 3-24+). Three sequential cycles of high-dose chemotherapy are feasible and were administered in this study with no mortality. Single agent paclitaxel at doses up to 825 mg/m2 were well tolerated with moderate reversible toxicity.

Adult↗
PubMed1997

Thiotepa and etoposide treatment of recurrent malignant gliomas: phase I study.

PURPOSE: To determine: (1) the maximum tolerable dose (MTD) of thiotepa (TT) that can be administered with etoposide without stem cell support; (2) whether this regimen is active against recurrent malignant gliomas. BACKGROUND: Although several chemotherapeutic agents show minor activity against recurrent brain tumors, there is no consensus about the most effective regimen. The alkylating agent TT has excellent central nervous system (CNS) penetration and is synergistic with the topoisomerase II inhibitor etoposide. DESIGN/METHODS: Fifteen patients with recurrent malignant gliomas (14 glioblastomas, 1 anaplastic astrocytoma) received intravenous etoposide 100 mg/m2 on days 1, 2, and 3, and intravenous TT (40, 50, 60, or 70 mg/m2) on day 2. All had received irradiation, and eight BCNU. Chemotherapy was repeated every 3-4 weeks, with stepwise TT dose increments of 10 mg/m2, provided toxicity was less than grade III. RESULTS: The major toxicity was dose-limiting leukopenia. The MTD of TT in cycle 1 was 60 mg/m2. All patients died of progressive disease and none died of chemotherapy-related complications. CONCLUSIONS: The MTD of TT in this regimen for recurrent malignant gliomas is 60 mg/m2. Higher doses of TT would require colony-stimulating factors or stem cell support.

Adolescent↗
PubMed1996

Retroviral transfer and expression of the human multiple drug resistance (MDR) gene in peripheral blood progenitor cells.

The multiple drug resistance (MDR) gene P-glycoprotein product is a transmembrane efflux pump that prevents toxicity of a variety of chemotherapeutic agents, including the anthracyclines, Vinca alkaloids, podophyllins, and taxol. The bone marrow toxicity of these drugs is due to the low or absent expression of MDR in marrow cells. Transfer and expression of the human MDR gene into bone marrow progenitors should prevent this toxicity. We report here the efficient transfer and expression of the MDR gene by retroviral-mediated gene transfer into CD34(+) cells isolated from peripheral blood progenitor cells (PBPCs), comparable to that obtained using bone marrow-derived progenitors. Optimal MDR transduction of these PBPC-derived cells requires exposure to growth factors and a period of preincubation. In addition, we demonstrate that we can transduce up to 100% of progenitor cells derived from PBPCs and can protect up to 25% of these progenitors from a dose of taxol toxic to untransduced controls.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1995

A semiautomated technique for volume reduction of stem cell suspensions for autotransplantation.

Infusion of thawed cryopreserved autologous stem cells (SC) is associated with a variety of complications due to the presence of dimethyl sulfoxide (DMSO) and free hemoglobin and to volume overload. Commonly, the DMSO is not removed before infusion for fear that prolonged in vitro exposure of the cells to DMSO leads to loss of clonogenic activity. We describe a simple technique for the substantial reduction in volume and DMSO content of bone marrow (BM) and peripheral blood stem cell (PBSC) suspensions. Sixty-five patients were transplanted with thawed, volume-reduced SC cryopreserved according to Stiff et al. Semiautomated volume reduction was performed on a COBE 2991 cell processor. The median volumes of cryopreserved SC were 1152 ml and 933 ml for the pools of PBSC products and the mixed pools of BM and PBSC, respectively, whereas the volume of SC infused was 153 ml (78% reduction). There were no differences in cell recoveries between PBSC and BM (98%). Only 2 patients demonstrated minimal side effects during infusion. A cohort of 16 metastatic breast cancer patients underwent PBSC harvests following chemotherapy/G-CSF priming and subsequent autotransplantation. Median time to an absolute neutrophil count > 500/microliters was 8 days (range 6-14 days), and median time to a platelet count > 20,000/microliters was 11 days (range 6-18 days). Volume reduction of SC products without the risk of graft failure was performed simply and resulted in few complications during infusion.

Cell Separation↗
PubMed1994

Transfer and expression of the human multiple drug resistance gene in human CD34+ cells.

The human multiple-drug resistance (MDR1) gene has been transferred into human hematopoietic progenitors using retroviral gene transfer. Human bone marrow cells and isolated CD34+ cells isolated from marrow were exposed to growth factors interleukin-3 (IL-3), IL-6, and stem cell factor for 48 hours and then to two changes of MDR retroviral supernatants over the next 24 hours. Progenitor assays in methylcellulose at this time showed that 18% to 70% of BFU-E and 30% to 60% of CFU-GM contain the transferred MDR gene by polymerase chain reaction analysis. Up to 11.2% of the progeny of these cells express increased amounts of MDR glycoprotein on their surface by fluorescence-activated cell sorter (FACS) analysis. In addition, transduced cells are enriched in high MDR-expressing cells after exposure to taxol as assessed by FACS analysis, and by resistance of BFU-E to taxol (Bristol-Myers Squibb, Princeton, NJ). These studies indicate the feasibility of using MDR gene transfer as a means of enriching marrow for MDR-transduced cells. They also provide the basis of a phase 1 clinical protocol in patients with advanced cancers not involving the bone marrow for the use of MDR gene transfer as a means of protecting marrow cells, which normally express low levels of MDR, from the myelosuppressive effects of drugs like taxol.

Antigens, CD↗
PubMed1991

Somatic gene therapy.

Many problems obviously continue to exist in gene transfer using retroviruses as a means of inserting foreign DNA into hematopoietic stem cells, especially with regulated genes such as the human beta globin genes. First, it is unclear whether the available retroviral vectors will infect enough stem cells for gene transfer to be successful over the long term. Second, there may be sequences necessary for normal beta globin gene expression that may also inhibit the normal retroviral life cycle, thus decreasing the efficiency of gene transfer or gene expression. It seems clear that in order to optimize the success of gene transfer, the highest possible titer of viral production is necessary. New approaches are aimed at increasing viral titer. The transfect/infect method appears useful. Growth factors may also be useful by increasing stem cell proliferation. Single growth factors may not be sufficient to optimize stem cell cycling. To date, interleukin-3 seems to be the single most useful growth factor, although interleukin-3 with interleukin-6 or other combinations of growth factors including interleukin-1 and granulocyte-macrophage colony-stimulating factor (GM-CSF) appear to have potential. Future work also is required to optimize the number of marrow stem cells needed for successful transplantation. Long-term bone marrow culture and stromal cell cultures may provide new and improved marrow culture conditions for achieving this goal. Improvements in the efficiency of both gene transfer and gene expression are necessary before we can consider the concept of gene transfer for the treatment of various hematologic genetic diseases in humans.

Animals↗