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W Krüger

Publications and source records attributed to W Krüger.

At least 37 records · Page 2Linked to original sources
PubMed2001

Real-time quantitative Y chromosome-specific PCR (QYCS-PCR) for monitoring hematopoietic chimerism after sex-mismatched allogeneic stem cell transplantation.

Y chromosome-specific sequences can be used to detect remaining male cells after sex-mismatched allogeneic blood stem cell transplantation (HSCT) involving a male patient and female donor, which represents approximately 25% of all cases. We developed a quantitative Y chromosome-specific PCR assay (QYCS-PCR) based on the DFFRY gene for the determination of hematopoietic donor chimerism. We analyzed blood and marrow samples from more than 40 patients at various time points after both standard and nonmyeloablative allogeneic HSCT. We found that real-time PCR combines extreme sensitivity, with a detection level of less than 1 male in 100,000 female cells (<0.001%), with very good reproducibility, especially in the important range of minor host chimerism. QYCS-PCR results were in close agreement with data from other techniques as bcr/abl-PCR and/or fluorescent in situ hybridization (FISH) analysis. In two relapsed patients, increasing numbers of Y-positive hematopoietic cells indicated recurrence of malignant disease prior to clinical confirmation. In conclusion, quantitative Y chromosome-specific PCR is a promising approach for monitoring the extent of chimerism in blood and other tissues after sex-mismatched hematopoietic stem cell transplantation (HSCT) or organ transplantation.

Adolescent↗
PubMed2000

Allogeneic bone marrow transplantation for refractory mantle cell lymphoma.

We report about a 28-year-old woman with relapsed mantle cell lymphoma (MCL, centrocytic lymphoma according to the Kiel classification) refractory to salvage chemotherapy. The patient underwent allogeneic bone marrow transplantation from a HLA-identical brother after myeloablative chemotherapy consisting of busulfan, etoposide, and cyclophosphamide. The patient experienced hepatic toxicity (grade I), mucositis (grade II) according the Bearman scale, and graft versus host disease of the skin (grade II) and showed stable engraftment with complete chimerism on day 15 after bone marrow transplantation. Eight years after transplantation, the patient is still disease free and in good condition without any late side effects. This report suggests a curative potential of allogeneic stem cell transplantation in MCL.

Adult↗
PubMed2000

Dose-dependent effect of etoposide in combination with busulfan plus cyclophosphamide as conditioning for stem cell transplantation in patients with acute myeloid leukemia.

To evaluate the efficacy and toxicity of two different etoposide (VP-16) dosages (30 or 45 mg/kg) in combination with busulfan/cyclophosphamide as conditioning therapy followed by stem cell transplantation in acute myeloid leukemia (AML), 90 patients with AML received either 30 mg/kg (n = 60) or 45 mg/kg (n = 30) etoposide in combination with busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg). The stem cell source was allogeneic related bone marrow (BM) (n = 53), allogeneic unrelated BM (n = 5), allogeneic unrelated peripheral blood (PBSC) (n = 2), syngeneic BM (n = 2), autologous BM purged (n = 9) or unpurged (n = 9), autologous PBSC (n = 10). Fifty-six patients (62%) were in first CR, 26 (29%) were > first CR, and eight (9%) were transplanted in relapse. Principal toxicities in both groups were mucositis and hepatotoxicity. Forty-five mg/kg etoposide resulted in greater hepatic toxicity (P = 0.03), and a higher incidence of VOD (23 vs 12%, P = 0.04) and acute GVHD grade III/IV (13 vs 5%, NS). The treatment-related mortality was 17% in the 30 mg/kg group and 33% in the 45 mg/kg group, mainly due to infections, intestinal pneumonia and GVHD. Hematological recovery of leukocytes 1/nl was comparable in both groups (17 vs 16 days). After a median follow-up of 16 months 19% in the 30 mg/kg group and 23% in the 45 mg/kg group relapsed. In patients who had undergone allogeneic related bone marrow transplantation in first CR no relapses occurred after a median follow-up of 3 years. For all patients the 3-year estimated disease-free survival was 62% in the 30 mg/kg group and 40% in the 45 mg/kg group (P = 0.03). For patients in first CR who underwent allogeneic related stem cell transplantation the 3 year disease-free survivals were 80% and 66%, respectively (P = 0.4). We conclude that etoposide 30 mg/kg or 45 mg/kg in combination with busulfan/cyclophosphamide is a highly active regimen for bone marrow transplantation of patients with AML with a low relapse rate. However, conditioning with 30 mg/kg rather than 45 mg/kg etoposide resulted in less toxicity and a better overall survival due to a lower transplant-related mortality. Bone Marrow Transplantation (2000) 26, 711-716.

Acute Disease↗
PubMed2000

Immunomagnetic tumor cell selection--implications for the detection of disseminated cancer cells.

BACKGROUND: The optimal method for the detection of disseminated epithelial cancer cells has not yet been found. The standard method, using immunocytochemistry, offers a sensitivity of up to 10(-6). Molecular methods such as cytokeratin-19 RT-PCR are about 10 times as sensitive, but they are hampered by interference such as illegitimate gene expression. STUDY DESIGN AND METHODS: Immunomagnetic bead selection of epithelial cancer cells using conjugates directed against the human epithelial antigen (HEA) followed by immunocytochemistry testing was investigated in this trial. RESULTS: No cytokeratin-positive cells could be enriched from 56 control samples. In 104 clinical samples of bone marrow aspirations, PBPC collections, and venous blood obtained from breast cancer patients, the cytokeratin-positive rate increased significantly, from 29.9 percent before selection to 54.8 percent after enrichment. Even the yield of detected cancer cells was significantly higher after selection. Up to 2.5 x 10(8) MNCs were easily processed. However, the mean cancer cell recovery after HEA enrichment was only 24.4 percent. Subsequently, selected epithelial cells were successfully immunophenotyped by use of a double-stain technique detecting cytokeratin-positive cells and the urokinase-like plasminogen activator receptor. CONCLUSION: HEA bead selection in combination with the standard immunocytochemistry method is a powerful and specific tool for the detection of disseminated cancer cells without false-positive results. Furthermore, it delivers enough cells for subsequent investigations such as characterization studies.

Antigens, Surface↗
PubMed2000

Expression of human milk fat globulin proteins in cells of haemopoietic origin.

Lineage-specific gene expression has been used for the identification of metastasis of cancers with unknown primary site or of disseminated cancer cells in haemopoietic compartments such as bone marrow or in lymph nodes. For the muc1, cytokeratin-19 and the CEA genes, the transcription in haemopoietic cells has been shown recently. Here, the expression of the mammary epithelium related antigens BA46 (lactadherin) and BA70 in lymphoid and myeloid cell lines, and in clinical specimens is analysed. By Northern-hybridization with specific oligonucleotides an ubiquitous transcription of both genes, independent from the provenance of cells or the chromosomal gender was found. Both mRNA molecules were amplified by rtPCR from the samples and the specificity could be confirmed by sequence analysis. Peptide-specific antibodies were raised in rabbits and used for Western-blot analysis and for immunocytochemical studies. Both antibodies reacted with total cell lysates from myeloid and lymphatic cells. In immunocytochemistry antibody P717 (anti-lactadherin) had a significant strong staining of the myeloid cell lines K562 and HL60 suggesting a participation of lactadherin in leukocyte-function. Using antibody P718, strong stains were seen in myeloid line K562 and lymphoid line ST486. In conclusion, our findings expand the results that the concept of lineage-specific gene expression is no longer valid at the molecular level.

Amino Acid Sequence↗
PubMed2000

Comparison of progenitor cell collection on day 4 or day 5 after steady-state stimulation with G-CSF alone in breast cancer patients: influence on CD34+ cell yield, subpopulation, and breast cancer cell contamination.

To determine the influence of apheresis timing on CD34+ cell yield, subpopulation, and breast cancer cell contamination, 48 women with breast cancer were stimulated from steady-state hematopoiesis in a prospective but nonrandomized study with 2 x 5 microg/kg G-CSF s.c. alone, and apheresis was started either on day 4 (n = 24) or day 5 (n = 24). Forty-eight women with breast cancer (stage II/III, n = 30; stage IV; n = 12; inflammatory, n = 6) and a median age of 44 years were well balanced between the two groups. In group I, aphersis was started on day 4 and additionally performed on day 5 after G-CSF stimulation, and in group II, apheresis was started on day 5. CD34+ cell count and CD34+ cell subpopulation were determined according to international criteria. Breast cancer cell contamination was detected by immunocytology. The median CD34+ cell harvest on day 4 was 3.3 x 10(6)/kg body weight (range 0.5-12.8) and 6 x 10(6)/kg BW (range 0.3-30) for patients starting on day 5 (p = 0.01). Those patients starting on day 4 achieved a median CD34+ cell count of 4 x 10(6)/kg (range 0.7-13) on day 5 (NS). Twenty-one percent of group I and 71% of group II achieved >5 x 10(6)/kg BW CD34+ cells in the first apheresis, whereas <2.5 x 10(6)/kg BW CD34+ cells in the first apheresis were observed in 38% of group I and 16% of group II. No differences were observed between the CD34+ cell subpopulations, CD34+/CD38+ (10.5% versus 10.5%) and CD34+/Thyl+ (1.5% versus 1.8%). The CD34+ cell harvest from consecutive collecting on days 4 and 5 was nearly identical to the harvest starting on day 5 (6.4 versus 6 x 10(6)/kg). Collecting CD34+ progenitor cells after stimulation with G-CSF alone on day 5 results in a significantly higher cell yield than starting collecting on day 4. No differences in respect to breast cancer cell contamination and CD34+ cell subpopulation were observed.

ADP-ribosyl Cyclase↗
PubMed2000

Efficacy of further attempts to mobilize CD34+ peripheral stem cells with alternative procedures after primary failure.

19 patients who failed the target collection of at least 2.5 x 10(6) CD34+ cells/kg underwent further mobilization procedures either with granulocyte-colony-stimulating factor (G-CSF) alone after failure to chemotherapy plus G-CSF (group 1), or with chemotherapy plus G-CSF (group 2), or with high-dose G-CSF (24 microg/kg) alone (group 3) after failure to respond to standard dose of G-CSF (10 microg/kg) alone. In all groups, an increase in median CD34+ cell yield could be observed following alternative procedures (1.1- to 1.9 x 10(6) kg; p = 0.02). The highest increase in CD34+ cell harvest was achieved in group 1 (0.85 to 2.2 x 10(6) kg), followed by group 2 (1. 2 to 1.7) and group 3 (1.0 to 1.4), but without statistically significant difference between the mobilization technologies. All patients with more than 1.0 x 10(6) CD34+ cells/kg in the first apheresis procedure reached the overall target of 2.5 x 10(6) CD34+ cells/kg after a second or subsequent mobilization procedure. In contrast, only 3 of 8 patients (37%) with less than 1.0 x 10(6) CD34+ cells in the first harvest could reach the target of 2.5 x 10(6) CD34+ cells after further mobilization attempts.

Adolescent↗
PubMed2000

A randomized comparison of once versus twice daily recombinant human granulocyte colony-stimulating factor (filgrastim) for stem cell mobilization in healthy donors for allogeneic transplantation.

To evaluate the schedule dependency of granulocyte colony-stimulating factor (G-CSF) (filgrastim) for stem cell mobilization, we conducted a randomized comparison in 50 healthy donors, with one subcutaneous daily injection of 10 microg/kg G-CSF (n = 25) compared with twice injections daily of 5 microg/kg G-CSF (n = 25). The two groups were well balanced for age, body weight and sex. G-CSF application was performed on an out-patient basis and leukapheresis was started in all donors on day 5. The most frequent side-effects of G-CSF were mild to moderate bone pain (88%), mild headache (72%), mild fatigue (48-60%) and nausea (8%) without differences between the two groups. The CD34(+) cell count in the first apheresis was 5.4 x 10(6)/kg donor weight (range 2.8-13.3) in the 2 x 5 microg/kg group compared with 4.0 x 10(6)/kg (range 0.4-8.8) in the 1 x 10 microg/kg group (P = 0.007). The target of collecting > 3.0 x 10(6) CD34(+) cells/kg donor weight with one apheresis procedure was achieved in 24/25 (96%) donors in the 2 x 5 microg/kg group and in 17/25 (68%) donors in the 1 x 10 microg/kg group. The target of collecting > 5.0 x 10(6) CD34(+) cells/kg in the first apheresis was achieved in 64% in the 2 x 5 microg/kg group, but in only 36% in the 1 x 10 microg/kg group. The progenitor cell assay for granulocyte-macrophage colony-forming units (CFU-GM) and erythroid burst-forming units (BFU-E) was higher in the 2 x 5 microg/kg group than in the 1 x 10 microg/kg group (7.0 vs. 3.5 x 10(5)/kg, P = 0.01; 6.6 vs. 5.0 x 10(5)/kg; P = 0.1). Administering G-CSF (filgrastim) at a dosage of 5 microg/kg twice daily rather than 10 microg/kg once daily is recommended; this leads to a higher CD34(+) cell yield and requires fewer apheresis procedures without increasing toxicity or cost.

Adult↗
PubMed1999

Tumour cell detection in G-CSF mobilised stem cell harvests of patients with breast cancer.

Peripheral blood stem cells were mobilised with G-CSF from steady-state haemopoiesis after previous anthracyclin-containing standard dose chemotherapy in patients with high-risk breast cancer. 48 samples were obtained from patients with stage II-III breast cancer and > or = 10 lymph nodes, 15 samples from patients with chemotherapy sensitive metastatic disease, and 13 samples from women with inflammatory breast cancer. 44 samples were first or single leukaphereses and 32 samples were second or third harvests. Aliquots were searched for contaminating tumour cells by immunocytochemistry (IC) and cytokeratin-19 reverse transcriptase polymerase chain reaction rtPCR). The median count of MNCs examined by IC was 2 x 10(6); cDNA prepared from 2 x 10(7) cells was subjected to PCR. Fifty-nine samples were examined by immunocytochemistry, 36 samples by rtPCR, and 19 samples by both techniques. Samples investigated by IC and rtPCR were judged as positive if there was at least one positive test. On the whole, 42/79 (55.3%) of the samples were positive with an insignificant trend to a higher positivity rate in second or subsequent leukaphereses (52.3% vs 59.3%). The median tumour cell load per 10(6) MNCs was low with 0.5 (0-7) cells in all, and a total of 2.2 (0.5-7) cells in positive specimen. Differences in the cancer cell load of first and subsequent leukaphereses and between subgroups of patients were not found. PCR and IC gave consistent results in 63.2%. This phenomenon can be explained by the greater sensitivity of the molecular method and by a Poisson distribution of coharvested tumour cells in samples. Tumour cell contamination in G-CSF mobilised stem cells from patients with breast cancer from steady state haemopoiesis after preceding anthacyclin-containing chemotherapy is frequent, but the tumour cell load is low. To allow a comparison of different studies dealing with cancer cell contamination in stem cells, standardisation of assays is necessary.

Breast Neoplasms↗
PubMed1999

Detection of micrometastasis by cytokeratin 20 RT-PCR is limited due to stable background transcription in granulocytes.

The reverse transcription polymerase chain reaction (RT-PCR) amplification of cytokeratin 20 (CK20) mRNA is considered a promising candidate method for the detection of circulating tumour cells in bone marrow and peripheral blood of cancer patients. In this study we have investigated the diagnostic specificity of the CK20 mRNA detection in samples from healthy donors (HD; n = 33), intensive care units patients (ICU; n = 20) and bone marrow obtained from patients suffering from chronic inflammatory diseases (CID; n = 14). RNAs purified from stabilized lysates showed positive results in 24% of the HD group (8/33), 35% of the ICU group (8/20) and in 40% of the CID group (5/14). The use of Ficoll gradients to separate nucleated cells completely restored the specificity of this CK20 RT-PCR assay. The CK20-expressing cells are positively identified to belong to the granulocyte fraction of leucocytes, which appear to express the gene on a background level. Our results demonstrate for the first time that CK20 mRNA expression is not limited to epithelium. Its occurrence in normal granulocytes has to be considered in tests designed to detect circulating cancer cells or micrometastases.

Biomarkers, Tumor↗
PubMed1999

Stem cell mobilization with G-CSF alone in breast cancer patients: higher progenitor cell yield by delivering divided doses (2 x 5 microg/kg) compared to a single dose (1 x 10 microg/kg).

We investigated the schedule dependency of G-CSF (10 microg/kg) alone in mobilizing peripheral blood progenitor cells (PBPC) in breast cancer patients. After a median of three cycles (range, 2-6) of anthracycline-based chemotherapy, 49 patients with breast cancer (stage II/III, > or = 10+ Ln n = 36; locally advanced/inflammatory n = 8, stage IV (NED) n = 5) underwent PBPC collection after steady-state mobilization either with 1 x 10 microg/kg (n = 27) or with 2 x 5 microg/kg (n = 22) G-CSF daily for 4 consecutive days until completion of apheresis. Apheresis was started on day 5. Priming with 2 x 5 microg/kg resulted in a higher median number of CD34+ cells (5.8 vs 1.9 x 10(6)/kg, P = 0.003), MNC (6.6 vs 2.6 x 10(8)/kg, P < 0.001) and CFU-GM (6.5 vs 1.3 x 10(4)/kg, P = 0.001) in the first apheresis than with 1 x 10 microg/kg. Also the overall number of collected BFU-E was higher in the 2 x 5 microg group (9.2 vs 3.1 x 10(4)/kg; P = 0.01). After high-dose chemotherapy with cyclophosphamide/thiotepa/mitoxantrone (n = 46) hematopoietic engraftment with leukocyte count > 1.0/nl was reached in both groups after a median of 10 days (range, 8-15) and with platelets count > 50/nl after 12 (range, 9-40) and 13 days (range, 12-41), respectively. A threshold of > 2.5 x 10(6)/kg reinfused CD34+ cells ensured rapid platelet engraftment (12 vs 17 days; P = 0.12). Therefore, the target of collecting > 2.5 x 10(6) CD34+ cells was achieved in 21/27 (80%) patients of the 1 x 10 microg group and in 21/22 (95%) patients of the 2 x 5 microg/kg group with a median of two aphereses (range, 1-4). None in the 10 microg/kg group, but 6/22 (28%) patients in the 2 x 5 microg/kg group required only one apheresis procedure, resulting in fewer apheresis procedures in the 2 x 5 microg/kg group (mean, 1.8 vs 2.3, P = 0.01). These results demonstrate that priming with 10 microg/kg G-CSF alone is well tolerated and effective in mobilizing sufficient numbers of CD34+ cells in breast cancer patients and provide prompt engraftment after CTM high-dose chemotherapy. G-CSF given 5 microg/kg twice daily (2 x 5 microg) leads to a higher harvest of CD34+ cells and required fewer apheresis procedures than when given 10 microg/kg once daily (1 x 10 microg).

Adult↗
PubMed1999

Early infections in patients undergoing bone marrow or blood stem cell transplantation--a 7 year single centre investigation of 409 cases.

Infections are a major cause of morbidity and mortality in patients undergoing high-dose therapy and subsequent autologous or allogeneic haemopoietic stem cell transplantation, despite the change from topical to systemic anti-infection prophylaxis and the introduction of growth factors and new antimicrobial drugs. We report our single centre experience with data from 409 patients treated at our unit from its opening in 1990 until May 1997. Three hundred and seventy-eight patients were transplanted for the first time, 12 patients were retransplanted or boosted and 19 patients were readmitted for miscellaneous reasons. 245 patients were allografted and 157 autografted. Antimicrobial prophylaxis was mainly quinolones, fluconazole plus amphotericin-B orally, aciclovir, and TMP/SMX or pentamidine. Three hundred and nineteen (78%) developed fever of significantly longer duration in the allogeneic setting with anti-CMV seropositivity. The most frequent infection was fever of unknown origin (50.6%), followed by septicaemia (12.5%) and pneumonia (11.0%). Pathogens isolated in 24.6% of the infections were mostly gram-positive bacteria (57.9%), followed by non-fermenting rods (11.2%), Aspergillus spp. and Candida spp. (10.3%, each). Cumulative response rate to antimicrobial therapy was 66.9%. Infections were responsible for 62.5% (25/40) of deaths after transplantation. Predominant pathogens were Aspergillus spp. (11), Candida spp. (four), and Pseudomonas spp. (three). None of the patients died from gram-positive bacterial infection. The risk of dying from infection was 11.2% after allografting and 0.8% after autotransplantation. Infections remain a major risk for early death after allogeneic transplantation of haemopoietic stem cells. Infection with gram-negative bacteria can be prevented by quinolone prophylaxis. Predominant pathogens are Aspergillus spp. Candida spp. and nonfermenting rods. Systemic infection with these pathogens is associated with a poor prognosis. Antimycotic prophylaxis and the therapy must be improved.

Adolescent↗
PubMed1999

Use of a five-agent GVHD prevention regimen in recipients of unrelated donor marrow.

A five-agent GVHD prophylaxis programme consisting of cyclosporin A, methotrexate, anti-thymocyte-globulin, pentaglobin and metronidazol was given to 48 recipients of unrelated donor marrow with chronic myelogenous leukemia, acute leukemia, myelodysplastic syndromes, and familiar lymphocytic hemophagocytosis of an average age of 33.5 (0.6-56) years. GVHD grades II-IV occurred in 18 patients (39%) and grades III-IV in five patients (11%). Chronic GVHD developed in nine patients (23%), three limited and six extensive. Fifteen patients died. Clinical relapse was detected in eight patients. Four patients died as a consequence of the underlying disease and subsequent treatment, 11 patients died of transplant-related causes. After a median follow-up of 19 months, the overall and disease-free survival are 67% and 62%, respectively. Survival by age is as follows: 0-19 years: 12/13 patients; 20-39 years: 14/25 patients; 40-59 years: 7/10 patients. The five-agent GVHD prophylaxis regimen is effective. Matched-unrelated donor transplants can be carried out safely in patients younger than 50 years of age. The results in patients younger than 20 years of age should encourage matched-unrelated donor transplants at earlier stages of the disease.

Adolescent↗
PubMed1999

Improved outcome in haemophagocytic lymphohistiocytosis after bone marrow transplantation from related and unrelated donors: a single-centre experience of 12 patients.

Haemophagocytic lymphohistiocytosis (HLH) is an autosomal recessive disease with histiocytic and lymphocytic infiltrations in multiple organs. Cure seems possible only by allogeneic bone marrow transplantation (BMT), but matched sibling donors (MSD) are restricted and high mortality rates are associated with BMT from unrelated donors (URD). We report on 12 consecutive HLH patients with an improved outcome following URD transplants. Eight patients received BMT from URD, four from MSD. Five patients had signs of active HLH at the time of BMT. The conditioning regimen consisted of 20 mg/kg busulphan, 60 mg/kg VP-16 and 120 mg/kg cyclophosphamide and, in case of URD, 90 mg/kg antithymocyte globulin. The doses of busulphan and VP-16 were reduced during the programme to 16 mg/kg and 30 mg/kg, respectively. Using a fivefold graft-versus-host disease (GVHD) prophylaxis, GVHD was absent or mild in 10, and moderate or severe in two patients undergoing unrelated transplants. One patient with URD experienced graft failure and was retransplanted on day 37. Major toxicities were hepatic veno-occlusive disease in five, capillary leak syndrome in two, pneumonia in three, sepsis in one, severe mucositis in one and seizures in two patients. All patients are alive without HLH after a median follow-up of 24.5 months. One patient has chronic GVHD, another patient has severe retardation. Three patients show slight to moderate development delay. These results indicate that in HLH, BMT from matched unrelated donors should be performed. Incomplete resolution of disease activity need not impede a successful outcome.

Adolescent↗