Biomedical subjects

M Bornhäuser

Publications and source records attributed to M Bornhäuser.

65 records · Page 4Linked to original sources

PubMed1999

Stable engraftment after megadose blood stem cell transplantation across the HLA barrier: the case for natural killer cells as graft-facilitating cells.

BACKGROUND: The case of a patient with chronic myelogenous leukemia who underwent transplantation with highly purified CD34+ peripheral blood stem cells from his two-antigen-mismatched mother is reported. No graft-versus-host disease has been observed so far and stable engraftment has been documented until day 100. METHODS: Weekly analysis of chimerism in different cellular subsets was performed using a quantitative polymerase chain reaction assay for nine short tandem repeat markers in leukocytes sorted by fluorescence-activated cell sorting. RESULTS: No donor CD4+ or CD8+ T cells have been detected up to 3 months after transplantation, whereas a rapid increase of donor CD56+ natural killer (NK) cells was observed in parallel with circulating donor CD34+ progenitors and myeloid cells. CONCLUSIONS: Because the graft contained virtually no T and NK cells, we believe the rapid in vivo generation of NK cells supported stable engraftment across the HLA barrier. The differentiation of CD34+ progenitors into NK cells might be a distinct feature of megadose stem cell transplants.

Adult↗

PubMed1999

Peripheral blood stem cell transplantation from unrelated donors: a comparison with marrow transplantation.

Peripheral blood stem cell (PBSC) transplants from HLA-A, -B, and -DR compatible unrelated donors (n = 45) were compared with bone marrow (BM; BM group, n = 45). Eighteen patients received CD34-selected PBSC (CD34 group). The PBSCs contained more mononuclear cells, CD34(+), CD3(+), and CD56(+) cells compared with marrow (P <.001). Engraftment was achieved in all 45 patients in the BM group, in 43 of 45 (95%) in the PBSC group, and in 14 of 18 (78%) in the CD34 group (P <.01). In multivariate analysis, a short time to absolute neutrophil count (ANC) equal to 0.5 x 10(9)/L was associated with the PBSC/CD34 groups (P <.001) and granulocyte colony-stimulating factor (G-CSF) treatment (P =.017). A short time to platelets equal to 50 x 10(9)/L was associated with PBSC (P =. 003) and no methotrexate (P =.015). Grades II-IV acute graft-versus-host disease (GVHD) was 20% in the BM controls, 30% in the PBSC group, and 18% in the CD34 group (not significant [NS]). The probability of chronic GVHD was 85% in the BM group, 59% in the PBSC group, and 0% in the CD34 group (P <.01). One-year transplant-related mortality was 21% and 27% and survival was 53% and 54% in the BM and PBSC groups, respectively (NS). The 2-year relapse-free survival was 41% and 46% in the two groups, respectively.

Adult↗

PubMed1999

Mycophenolate mofetil and cyclosporine as graft-versus-host disease prophylaxis after allogeneic blood stem cell transplantation.

BACKGROUND: Mycophenolate mofetil (MMF) is an inhibitor of purine nucleotide de novo synthesis leading to impaired proliferation of activated lymphocytes. Studies in animals show a synergistic effect of MMF and cyclosporine (CsA) in preventing acute graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation. We performed a pilot study evaluating the feasibility of the combined application of MMF and CsA as GVHD prophylaxis after allogeneic blood stem cell transplantation. Toxicity and the bioavailability of MMF in this setting were investigated. METHODS: Fourteen patients who had received grafts from HLA-compatible siblings received 2 g of oral MMF from day 1 to 14 combined with intravenous CsA at 4 mg/kg starting at day-1. Plasma levels of mycophenolic acid (MPA) and its glucoronide were measured by high-performance liquid chromatography. Fifteen patients treated with a combination of CsA and methotrexate at the same institution were referred to as the control group. RESULTS: Trilineage engraftment was achieved in all study and control patients. Acute GVHD > or = grade II was observed in 46.5% and 60% of the study and control patients, respectively. No major differences in the rate of acute toxicities were detectable. The mean trough blood level of MPA in 10 patients was 0.28 microg/ml, and 5.7 microg/ml for MPA glucoronide. Reduced peak levels of MPA indicate a reduced absorption rate of MMF in the early posttransplant phase. CONCLUSIONS: The combined administration of MMF and CsA was shown to be feasible in patients after allogeneic blood stem cell transplantation. Because of the decreased bioavailability of MMF, dose-finding studies for an intravenous formulation are warranted.

Adult↗

PubMed1999

Defining optimum conditions for the ex vivo expansion of human umbilical cord blood cells. Influences of progenitor enrichment, interference with feeder layers, early-acting cytokines and agitation of culture vessels.

Ex vivo expansion of human umbilical cord blood cells (HUCBC) is explored by several investigators to enhance the repopulating potential of HUCBC. We performed experiments using either Ficoll-separated or CD34+-selected HUCBC from the same donation in serum-free medium. CD34-purified HUCBC were cultured on either human umbilical vein endothelial cells (HUVEC) or irradiated bone marrow-derived stroma cells (BMSC) with addition of different cytokines. In addition, we tested the expansion of HUCBC in culture vessels with continuous rotation. CD34 enrichment led to a significant increase in the expansion factor of CD34+ cells compared with unmanipulated HUCBC. BMSC were more efficient in amplifying early progenitors than HUVEC. Optimum results were reached by a combination of SCF, FLT-3L at 300 ng/ml and IL-3 at 50 ng/ml. No significant improvement in the expansion of CD34+/38- primitive progenitors could be obtained with other combinations. Addition of megakaryocyte-derived growth and development factor to each growth factor cocktail improved the expansion results. Continuous rotation of culture vessels did not ameliorate the expansion rate of the analyzed subsets. Culture conditions separating stroma and HUCBC by a semipermeable membrane improved the expansion factors of CD34+, CD34+/38-, and CD34+/41+ cells and CFU-GM compared with contact cultures. These data might be useful when designing culture systems for clinical scale ex vivo expansion of HUCBC.

Antigens, CD34↗

PubMed1999

Flow cytometric DNA quantification in immunophenotyped cells as a sensitive method for determination of aneuploid multiple myeloma cells in peripheral blood stem cell harvests and bone marrow after therapy.

The simultaneous measurement of DNA content and myeloma-related antigens (B-B4 or CD38) by flow cytometry is proposed as a method for the detection of aneuploid plasma cells in peripheral blood stem cell (PBSC) harvests and in bone marrow after therapy. In 30 patients with initially detected aneuploid myeloma cells we evaluated the bone marrow after therapy and in eight of these patients 23 PBSC harvests were analyzed. In 13 of 23 PBSC harvests aneuploid myeloma cells were detectable (range: 0.02-0.63%). In the bone marrow of the 30 patients aneuploid plasma cells were detectable in all samples after chemotherapy (range: 0.12-35.70%) and after autologous PBSC transplantation in two of three patients (0.21% and 0.03%). Furthermore the relationship between diploid and aneuploid plasma cells can be evaluated. In the PBSC harvests the percentage of aneuploid plasma cells is significantly lower than that of diploid plasma cells (P=0.006). In contrast, in bone marrow the aneuploid plasma cells are predominant in most patients even after therapy (24 of 30 patients; P=0.0055). In the case of initially detected aneuploid myeloma cells, a contamination with malignant cells can be estimated with a simple flow cytometric method in PBSC harvests and in bone marrow after therapy.

Aneuploidy↗

PubMed1999

Rapid quantification of mixed chimerism using multiplex amplification of short tandem repeat markers and fluorescence detection.

Monitoring the engraftment of donor cells after allogeneic blood stem cell transplantation (BSCT) may be important for the early diagnosis of graft failure or relapse of disease. Several techniques have been reported for this purpose. PCR-based assays analyzing polymorphic short tandem repeat (STR) markers are attractive because they are sensitive and can be performed rapidly. The intent of the present study was to test a novel approach for the quantification of mixed chimerism using a commercial multiplex STR assay with fluorescence-based detection for forensic purposes. The feasibility of this assay and the accuracy of quantitative results was tested using serial cell mixtures of unrelated individuals. Sample preparation was optimized to obtain information from minute amounts of starting material, eg from patients with aplasia or from sorted cell populations. Using the STR-PCR, discrimination between donor and recipient was possible in all patients analyzed (n = 25). Cell dilution experiments showed a linear correlation between the cell numbers added and the proportions found, with the limit of detection for a minor cell population being 5%. Comparison of values obtained with standard FISH analysis in patients transplanted from sex-mismatched donors showed an excellent correlation with the STR-PCR results. Taken together, this procedure allows the rapid, versatile and accurate quantification of mixed chimerism, even with minuscule numbers of cells.

Amelogenin↗

PubMed1999

Detection of cytogenetic aberrations both in CD90 (Thy-1)-positive and (Thy-1)-negative stem cell (CD34) subfractions of patients with acute and chronic myeloid leukemias.

Acute myeloid leukemia (AML) and chronic myeloid leukemia (CML) are thought to arise from malignant hematopoietic progenitor cells representing early and undifferentiated stem cell clones. In CML there is evidence for a progenitor cell subset free of leukemic clones, depending on the course of the disease. Additionally, it has been suggested that in AML, the early stem cell compartment (CD34+/90+) does not harbor the malignant clone. We analyzed white blood cells from leukemia patients for the presence of aberrant cells in stem cell subfractions. Sixteen patients with CML, six patients with AML, two patients with acute lymphatic leukemia (ALL) and one with chronic myelomonocytic leukemia (CMMOL), all with known cytogenetic abnormalities, were evaluated according to their CD90 (Thy-1)-positive or -negative phenotype. Subsets were sorted on to slides and further characterized by FISH and/or standard cytogenetic testing. The bcr-abl translocation or gross chromosomal abnormalities could be detected in equally high amounts of 92.2% and 89.2% in both stem cell subsets. We conclude, that in progressed AML and CML cells characterized by specific genetic aberrations implicated in the malignant state can be found in the CD34+/CD90+ and CD90- population, thus making CD90 an inappropriate marker to distinguish benign from malignant cells in these leukemias.

Acute Disease↗

PubMed1998

Computer-based quality control in high-dose chemotherapy and bone marrow transplantation.

High-dose chemotherapy with autologous and allogeneic blood stem cell transplantation has become a standard therapy for hematological malignancies and solid tumors. To ensure quality of treatment and adherence to internationally approved protocols, the use of computer systems has been introduced in some oncology centers. Most software packages cannot be used automatically by other institutions because of different treatment strategies and medications. To overcome this problem, we designed a software system based on an Oracle database, which allows the user to develop his own therapy blocks and assemble them to generate specific therapy plans. The system supports the daily work of the physicians by suggesting medications based on changes in the vital parameters or the clinical chemistry. Parameters can be given upper and lower limits whose surpassing leads to treatment suggestions by the system. All quantitative variables may be depicted in a graphical way. The system is connected to external laboratory devices. Export of data to international registries is possible. Until now, 43 patients have been transplanted with the help of this system. There is a high degree of acceptance among the nursing staff and the physicians. The system can be transferred to other centers, if the local hardware and network capacities meet the minimal requirements.

Adult↗

PubMed1998

Fluorescence in situ hybridization for the BCR/ABL rearrangement is dependent on the percentage of nonlymphocytic cells in peripheral blood stem cell harvests.

Interphase fluorescence in situ hybridization (FISH) for the translocation t(9;22) is widely used for quantifying minimal residual disease (MRD) in PBSC harvests from CML patients. We investigated the influence of cell composition on the percentage of positive FISH signals in 17 BCR/ABL-positive leukapheresis products from 12 CML patients. In these PBSC harvests, a significant correlation between the percentage of nonlymphocytic nucleated cells and BCR/ABL positivity was measured (k=0.81). This correlation was not seen in patients who became BCR/ABL negative after mini-ICE chemotherapy. CD34 enrichment was performed by immunomagnetic separation in 7 patients. There was a statistically significant increase in BCR/ABL positivity after CD34+ selection (p=0.018). This may have been caused by passive depletion of BCR/ABL-negative lymphocytes. Our findings suggest that quantitative results of t(9;22) FISH have to be corrected for cell composition when comparing different stem cell products. CD34+ selection before FISH analysis may be one way to enrich for nonlymphocytic cells and to concentrate on the progenitor compartment.

Adult↗

PubMed1998

Acceptance and feasibility of peripheral stem cell mobilisation compared to bone marrow collection from healthy unrelated donors.

Allogeneic peripheral blood stem cell transplantation leads to an earlier engraftment compared to BMT. The feasibility, acceptance and long-term side-effects of G-CSF mobilisation of PBSC in unrelated healthy donors needs to be evaluated. Forty unrelated healthy donors received G-CSF in a dose of 10 microg/kg bodyweight for 5 days and two aphereses were performed. The donors were monitored prospectively. The data were compared to bone marrow harvests from unrelated donors. Almost all stem cell donors reported some side-effects due to Filgrastim application. Bone pain (32), headache (20), chest pain (two) and night sweats (one) were complained of. By taking analgesics, the pain was relieved in most cases. No donor discontinued the filgrastim application. Bone pain and headache resolved within 2-4 days after termination of Filgrastim application. There was, as expected, a seven-fold increase in the number of total WBCs. There were no significant changes of platelet counts during G-CSF application. After 4 weeks haemoglobin concentration and platelet counts showed no significant differences compared to baseline values. The aphereses were mostly tolerated very well. Eighteen donors reported paraesthesia, one donor developed dizziness, two complained of nausea and vomiting. There was a significant decrease in platelet count (242 before, 98 x 10(9)/l after aphereses). Autologous platelets were transfused after the second aphereses in four donors. These data were compared to data from 245 unrelated bone marrow donors, who had on average, 14 days bone pain and tiredness after donation. The G-CSF mobilisation and apheresis of peripheral blood stem cells is an alternative to traditional bone marrow harvesting in unrelated healthy donors. It is well tolerated and the duration of side-effects on average is shorter than after the surgical procedure. So far no long-term effects have been observed in the follow-up.

Adult↗

PubMed1997

Rapid engraftment after allogeneic ABO-incompatible peripheral blood progenitor cell transplantation complicated by severe hemolysis.

A patient with CML in accelerated phase received G-CSF-mobilized PBPC from an unrelated HLA genotypically matched donor. The blood groups of the patient and donor were bidirectionally incompatible. Hematologic recovery was rapid with > 500 PMN/microliter on day +9. Starting on day +5 bilirubin levels increased from 1.3 mg/dl up to a maximum of 18 mg/dl on day +14. Clinical signs and laboratory tests supported major hemolysis. Blood typing on day +16 revealed early blood-group change, consistent with donor-derived antibodies produced by passenger-lymphocytes which may have mediated severe hemolysis. The early onset and strong intensity of the hyperbilirubinemia could be a specific feature of ABO-incompatible allogeneic PBPC transplantation which would be difficult to differentiate from GVHD or VOD.

ABO Blood-Group System↗