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Dive into the research topics where U. W. Schaefer is active.

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Featured researches published by U. W. Schaefer.


Annals of Hematology | 2000

The amount of BCR-ABL fusion transcripts detected by the real-time quantitative polymerase chain reaction method in patients with Philadelphia chromosome positive chronic myeloid leukemia correlates with the disease stage

Ahmet H. Elmaagacli; Dietrich W. Beelen; Bertram Opalka; Siegfried Seeber; U. W. Schaefer

Abstract The use of the real-time reverse-transcription polymerase-chain reaction (RT-PCR) method to quantify BCR-ABL transcripts before and after allogeneic transplant was prospectively studied in 65 patients with chronic myeloid leukemia (CML). The expression of the BCR-ABL transcript was determined and normalized using the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) housekeeping gene product as an endogenous reference. In the single step real-time PCR assay, tenfold serial dilutions of cDNA of the K5652 cell line remained positive down to 100 pg cDNA only. However, molecular relapses of CML after transplant were only safely detectable when a nested real-time PCR assay was performed, which was able to detect 1–10 pg cDNA from a tenfold serial dilution. The median normalized BCR-ABL transcript level was measured as 0.004% in 17 patients with a molecular relapse, 0.4% in 7 patients with a cytogenetic relapse, 2.6% in 36 patients with a stable phase of CML, and 36% in 5 patients with a relapse in a blast crisis. The analyzed median normalized amount of BCR-ABL transcript differed significantly (P<0.001) between the various disease stages. In ten CML patients with relapse, the real-time PCR method was used to monitor the response of various immunotherapies as donor leukocyte infusions, withdrawal of immunosuppression, or interferon-α application. The results of the quantitative evaluation of BCR-ABL transcripts reflected very well the clinical effect of the different applied immunotherapies. The new real-time PCR method seems to be a suitable technique for the early detection of relapse after allogeneic transplant in patients with the BCR-ABL transcript. Its ability to distinguish between molecular and cytogenetic relapse (P<0.001) allows early therapeutic decisions.


Transplantation | 2002

Positive serum crossmatch as predictor for graft failure in HLA-mismatched allogeneic blood stem cell transplantation

Hellmut Ottinger; Vera Rebmann; Kerstin A. Pfeiffer; Dietrich W. Beelen; Bernhard Kremens; Volker Runde; U. W. Schaefer; Hans Grosse-Wilde

Background. Evaluation of patient sera for complement-fixing anti-donor antibodies (serum crossmatch [XM]) before allogeneic blood stem cell transplantation (BSCT) is routine in most centers. However, in contrast to kidney transplantation, the predictive value of a positive XM for outcome of BSCT is still unclear, and a positive XM is presently not regarded as an absolute contraindication to proceed to transplant. Methods. To clarify the role of a positive XM as predictor for overall survival (OS) and graft failure (GF) after BSCT, a retrospective, single-center, matched-pair analysis was performed. Enrolled were all XM-positive BSCT performed at our institution from 1985 to 2000 (n=30). Controls (n=30) were matched for disease, disease stage, patient age, period of transplant, conditioning regimen, protocol for prevention of graft-versus-host disease, and type of donor (related vs. unrelated, HLA-identical vs. HLA-mismatched). Results. Multivariate statistical analysis of all enrolled 60 transplants revealed GF as the all-dominating, independent risk factors for low OS (relative risk [RR]: 59.5, P <0.0001). Univariate (Kaplan-Meier) analysis could attribute inferior OS and high incidence of GF to the subgroup of HLA-mismatched, XM-positive transplants (P =0.01). Conclusions. A XM should always be performed in patients awaiting a BSCT from HLA-mismatched donors, because a positive XM is a predictor for inferior OS due to GF in BSCT.


British Journal of Haematology | 2001

Estimating the relapse stage in chronic myeloid leukaemia patients after allogeneic stem cell transplantation by the amount of BCR-ABL fusion transcripts detected using a new real-time polymerase chain reaction method

Ahmet H. Elmaagacli; Annette Freist; Meinhard Hahn; Bertram Opalka; Siegfried Seeber; U. W. Schaefer; Dietrich Wilhelm Beelen

We have used a new single‐step real‐time reverse transcription polymerase chain reaction (RT‐PCR) method to quantify BCR‐ABL transcripts, thereby estimating the relapse stage in chronic myeloid leukaemia patients after allogeneic transplants. In 402 samples from 172 patients, BCR‐ABL expression was determined and normalized, using the GAPDH housekeeping gene product as an endogenous reference. In our real‐time RT‐PCR assay, serial dilutions of RNA of the K562 cell line remained positive down to 7·5 pg. The median normalized BCR‐ABL amount differed significantly (P < 0·001) between the various disease stages and was 0·06% (range 0·001–1·55%), 3·2% (range 1·4–5·6%) and 21·5% (range 6·8 −827%) in 17 patients with a molecular relapse, in eight patients with a cytogenetic relapse and in 10 patients with a haematological relapse respectively.


Transplantation | 2003

Transfer of humoral and cellular hepatitis B immunity by allogeneic hematopoietic cell transplantation.

Monika Lindemann; Vahé Barsegian; Volker Runde; Melanie Fiedler; Klaus-Hinrich Heermann; U. W. Schaefer; Michael Roggendorf; Hans Grosse-Wilde

Background. Previous data indicate that a transfer of specific humoral and cellular immunity by way of allogeneic hematopoietic cell transplantation (HCT) should, in principle, be possible. Methods. In the HCT setting with a follow-up of up to 55 months, we studied the transfer of hepatitis B virus (HBV) specific immunity from electively immunized donors into HLA compatible recipients suffering from chronic myeloid leukemia (CML). After excluding preexisting HBV specific immunity in donor–recipient pairs, 27 prospective donors were vaccinated against HBV. In addition, on an average of 22 months postHCT, 8 of the 19 recipients were immunized once for HBV. Results. Donor vaccination resulted in detectable hepatitis B surface (HBs) antibodies in 85% of donors and specific cellular in vitro responses in 77%. Two weeks postHCT, 86 and 67% of the recipients displayed positive humoral and cellular HBV reactions, respectively, which then decreased. Afterwards, HBV immunity reappeared in 83% of the recipients without revaccination. Following a single vaccination in recipients, seven of eight displayed a typical memory response. An HBV specific response was already detectable 1 week after vaccination, approximately 1,300-fold (humoral) and 60-fold (cellular) higher than observed in the corresponding donors after a single immunization. Conclusions. The “spontaneous” recurrence of HBV immunity and the memory response in recipients give evidence for an elective immune transfer (e.g., for viral antigens) by way of allogeneic HCT.


Transplantation | 1990

Six weeks of continuous intravenous cyclosporine and short-course methotrexate as prophylaxis for acute graft-versus-host disease after allogeneic bone marrow transplantation.

Dietrich W. Beelen; Quabeck K; Kaiser B; Wiefelspütz J; Scheulen Me; Graeven U; Hans Grosse-Wilde; Sayer Hg; U. W. Schaefer

The feasibility and toxicity of six-week continuous intravenous 3 mg/kg/day eyclosporine (CsA) treatment in conjunction with a short course of methotrexate (MTX) was studied in 69 consecutive patients after HLA genotypically identical bone marrow transplantation. In light of the uncertain efficacy of prolonged oral CsA immunoprophylaxis in preventing de novo chronic graft-versus-host disease (GVHD). CsA treatment was terminated three months after BMT. Sixty-one (88%) patients received the full intravenous regimen and no patient exclusions were necessary due to intolerable adverse effects. Weekly median blood CsA concentrations ranged between 820 ng/ml in the first and 648 ng/ml in the sixth -week of treatment. No significant correlation existed between blood CsA concentrations and CsA dosages. Major adverse effects of the regimen included hypertension in 36%, acute nephrotoxicity in 36%, acute hepatotoxicity in 41%, and central nervous system toxicity in 4% of the patients. Since hepatotoxicity occurred predominantly in the early posttransplant period (median onset day 9), the relatively high incidence of this untoward effect might have been additionally caused by MTX and/or the preparative regimen. Blood CsA concentrations and CsA dosages did not significantly correlate with serum creatinine or total and conjugated bilirubin levels. In addition, blood CsA and serum creatinine levels did not differ between hypertensive and normotensive patients. Acute GVHD developed in 16% of the patients. Median CsA doses and blood CsA concentrations were identical for each week after BMT for patients contracting acute GVHD as compared with those without acute GVHD. In 55 patients surviving without acute or secondary chronic GVHD, the cumulative probability of de novo chronic GVHD after termination of CsA treatment was 13%. In conclusion, this regimen was tolerable and provided constant blood CsA concentrations for six postransplant weeks that were not adversely influenced by the development of acute GVHD. Restriction of CsA treatment to the first three months after BMT appeared not to increase the risk of de novo chronic GVHD, which challenges regimens employing oral CsA immunoprophylaxis for 6–12 months after BMT.


Cancer Genetics and Cytogenetics | 1988

Translocation t(8;16) in acute monocytic leukemia

Reinhard Becher; Oskar A. Haas; Ullrich Graeven; Peter Bettelheim; Peter F. Ambros; Michael Fridrik; U. W. Schaefer; C. G. Schmidt

A report is given of three new cases of acute monocytic leukemia, FAB M5a, with a t(8;16)(p11;p13). Two cases showed a marked erythrophagocytosis, including one with phagocytosis of normoblasts and granulocytes. Phagocytosis was absent in the third case. The t(8;16) was the only abnormality in two cases, whereas one case showed clonal evolution with partial trisomy 1q and a deletion of part of the short arms of chromosomes 1 and 3. Treatment results and survival were poor in all cases. A complete remission was achieved in two patients, which lasted only for 3 and 6 months, respectively. In one of these cases a central nervous system relapse occurred. Survival was short, lasting between 1 and 9 months. One patient succumbed to interstitial pneumonitis, a complication of allogeneic bone marrow transplantation without evidence for relapsing leukemia.


Annals of Hematology | 1984

Laminar air flow versus barrier nursing in marrow transplant recipients

Hossam K. Mahmoud; U. W. Schaefer; F. Schüning; C. G. Schmidt; M. Bamberg; E. Haralambie; G. Linzenmeier; D. Hantschke; Hans Grosse-Wilde; W. Luboldt; H. J. Richter

SummaryForty-eight patients with acute leukaemia in relapse (n=14), acute leukaemia in complete remission (n=19), chronic myeloid leukaemia (n=8) or severe aplastic anaemia (n=7) received a marrow transplant. The first 26 patients were nursed in laminar-air-flow plastic isolators while the next 22 patients were treated in barrier nursing rooms. Gnotobiotic parameters and morbidity in the 2 groups are compared. Good decontamination of the gastro-intestinal tract was obtained using either of the 2 isolation techniques. The incidence of bacterial and mycotic infections, as well as the supportive care required by the patients was almost equal in both groups. Our results also suggest that the incidence of graft versus host disease may decrease with efficient decontamination of the patients.


Annals of Hematology | 1985

Marrow transplantation for pancytopenia in dyskeratosis congenita

Hossam K. Mahmoud; U. W. Schaefer; C. G. Schmidt; R. Becher; G. F. Götz; H. J. Richter

SummaryA 33-year-old man with dyskeratosis congenita received a marrow transplant to treat severe pancytopenia. The graft was successful, but the patient developed severe acute graft-versus-host-disease grade IV and died 51 days post-grafting. — The outcome of transplantation in dyskeratosis congenita is compared to that in Fanconis anaemia due to the resemblance of both diseases in some aspects.


British Journal of Haematology | 1996

Bone marrow transplantation from partially HLA-matched related donors in adults with leukaemia: the experience at the University Hospital of Essen, Germany.

Hellmut Ottinger; Dietrich W. Beelen; Herbert G. Sayer; U. W. Schaefer; Hans Grosse-Wilde

The Seattle group has demonstrated that bone marrow transplantation (BMT) using partially HLA‐mismatched related donors is feasible in principal. However, it was unclear whether these results can also be achieved at smaller‐sized BMT units. Therefore a matched pair analysis enrolling 52 BMTs from partially HLA‐mismatched relatives and 52 control BMTs from HLA‐identical siblings was performed at the University Hospital of Essen. Overall survival (OS) and incidence of graft‐versus‐host disease (GVHD) did not differ significantly after study and control BMTs (OS: 52% v 63% 1 year, 46% v 48% 5 years post transplant; acute GVHD: 37% v 35%, chronic GVHD: 67% v 55%). After study BMTs, however, therapy‐related mortality (P = 0.018) and incidence of graft failure (P = 0.002) were increased, whereas relapse rate was reduced (11% v 27%). Two or three mismatches in HVG direction implied the same risk of graft failure as one mismatch. Therefore, (i) OS after BMT from one HLA antigen mismatched relative and from HLA‐identical siblings does not differ significantly even when performed at a ‘smaller’ centre; (ii) two or even three HLA mismatches in host‐versus graft (HVG) direction might be acceptable in family BMT for leukaemia.


Modern Pathology | 2001

Megakaryopoiesis and Myelofibrosis in Chronic Myeloid Leukemia after Allogeneic Bone Marrow Transplantation: An Immunohistochemical Study of 127 Patients

Juergen Thiele; Hans Michael Kvasnicka; Dietrich W. Beelen; Uta Flucke; Christian Spoer; Svetlana Paperno; Lutz-Dietrich Leder; U. W. Schaefer

An immunohistochemical and morphometric study was performed on 363 trephine biopsies of the bone marrow derived from 127 patients with chronic myeloid leukemia at standardized end points before and after allogeneic bone marrow transplantation (BMT). The purpose of this investigation was to evaluate features of CD61+ megakaryopoiesis related to successful engraftment. Further, we tried to elucidate possible associations of this lineage, including precursor cells, with the platelet count and reticulin fibrosis during the pretransplant and, specifically, post-transplant periods. A significant correlation was recognizable between the quantity of CD61+ megakaryocytes and the platelet values before BMT and also after completed hematopoietic recovery. In the very early post-transplant period, which is associated with severe thrombocytopenia, patchy regeneration of disarranged hematopoiesis occurred, including dysplastic megakaryocytes. According to planimetric measurements after BMT, the atypical micromegakaryocytes characteristic for chronic myeloid leukemia disappeared, and the engrafted donor bone marrow revealed a prevalence of normal-size cells of this lineage. On the other hand, normalization of megakaryocyte size was absent in sequential examinations of the few patients with a leukemic relapse who had a predominance of atypical dwarf forms comparable with chronic myeloid leukemia. Before BMT occurred, reticulin fiber density was significantly correlated with the number of CD61+ megakaryocytes and its precursor cell population. In 34 patients with myelofibrosis that occurred after myelo-ablative therapy and BMT, an initial regression was followed by an insidious recurrence of fibers concentrated in the areas of regenerating hematopoiesis. This postgraft reappearance of reticulin fibrosis was significantly associated with the quantity of megakaryocytes. Regarding engraftment parameters, pretransplant presence of (reticulin) myelofibrosis exerted a distinctive impact because of a delayed hematopoietic reconstitution according to standard clinical criteria. In line with this finding, slowed engraftment was also significantly related with higher pretransplant megakaryocyte and platelet counts.

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Dietrich W. Beelen

University of Duisburg-Essen

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Hans Grosse-Wilde

University of Duisburg-Essen

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C. G. Schmidt

St. Vincent's Health System

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Ahmet H. Elmaagacli

University of Duisburg-Essen

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