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N Schmitz

Publications and source records attributed to N Schmitz.

At least 145 records · Page 8Linked to original sources
PubMed1996

Early recurrence or persistence of autoimmune diseases after unmanipulated autologous stem cell transplantation.

Autologous stem cell transplantation with or without in vitro lymphocyte depletion has been suggested as a new treatment option for severe autoimmune diseases. We describe five patients with autoimmune diseases (CREST syndrome, myasthenia gravis and Hashimoto's thyroiditis, systemic lupus erythematosus, atopic dermatitis, and rheumatoid arthritis) who underwent autologous bone marrow (n = 1) or peripheral blood progenitor cell (n = 4) transplantation with unmanipulated grafts as treatment for the autoimmune disease in one case or as treatment for a malignant disorder with a concomitant autoimmune disorder in four cases. In all patients serological and clinical signs of the autoimmune disease recurred early or persisted. These observations should be regarded as a cautionary note concerning the efficacy of high-dose therapy followed by transplantation of unmanipulated autologous stem cells for treatment of severe autoimmune diseases.

Adult↗
PubMed1996

Randomised trial of filgrastim-mobilised peripheral blood progenitor cell transplantation versus autologous bone-marrow transplantation in lymphoma patients.

BACKGROUND: A randomised trial comparing filgrastim-mobilised peripheral blood progenitor cell (PBPC) transplants with autologous bone marrow transplantation (ABMT) for haematopoietic stem cell support has not been done. We compared the effects of filgrastim-mobilised PBPC or autologous bone marrow reinfused to lymphoma patients after high-dose chemotherapy in a prospective randomised multicentre trial. METHODS: The trial was done at six centres in three European countries. After high-dose chemotherapy (carmustine, etoposide, cytarabine, and melphalan [BEAM protocol]) 58 patients with advanced Hodgkin's disease or high-grade non-Hodgkin lymphoma received either filgrastim-mobilised PBPC (n = 27) or bone marrow (n = 31) for haemopoietic reconstitution. FINDINGS: The median number of days with platelet transfusions after grafting was 6 in the PBPC transplantation group and 10 in the ABMT group (estimate of treatment difference 5 days, 95% CI 3-7 days). Time to platelet recovery above 20 x 10(9)/L was 16 days in the PBPC transplantation group and 23 days in the ABMT group (p = 0.02). Time to neutrophil recovery above 0.5 x 10(9)/L was also reduced in the PBPC transplantation group (11 vs 14 days, p = 0.005). Patients randomised to PBPC transplantation needed fewer red blood cell transfusions (two vs three, p = 0.002) and spent less time in hospital (17 vs 23 days, p = 0.002). Early post-transplant morbidity and mortality as well as overall survival (median follow-up 311 days) were similar in both groups. There was no notable toxicity ascribed to filgrastim administration or the leucapheresis procedures. INTERPRETATION: In patients with lymphoma treated with high-dose chemotherapy, reinfusing filgrastim-mobilised PBPC instead of autologous bone marrow significantly reduced the number of platelet transfusions, the time to platelet and neutrophil recovery, and led to earlier discharge from hospital.

Adult↗
PubMed1996

Precast commercial polyacrylamide gels for separation of DNA amplificates by temperature gradient gel electrophoresis: application to clonality analysis of lymphomas.

The third complementary determining region (CDR-III) of the rearranged immunoglobulin heavy chain (IgH) genes represents a unique marker for a lymphocyte and its clonal descendants and can be amplified by the polymerase chain reaction (PCR) technique. This approach has markedly enhanced the sensitivity for detection of clonal lymphocyte populations in patients with malignant B-lymphoid neoplasias. To monitor minimal residual disease (MRD) in tissue specimens during or after antineoplastic treatment, the problem of detecting the presence of a few clonal (malignant) lymphocytes in coexistence with a majority of polyclonal lymphocytes has to be addressed. Semi-nested PCR amplification of CDR-III rearrangements from specimen infiltrated by tumor cells generates clonal signals in front of a polyclonal background, and therefore high resolution electrophoretic techniques for separation of DNA fragments are required. Temperature gradient gel electrophoresis (TGGE) resolving DNA homo- and heteroduplexes according to their thermal stability has been successfully applied for this purpose using special electrophoretic equipment. We describe an adjustment to this technique by using a commercially available precast 0.5 mm thick polyacrylamide gel and by changing a standard horizontal electrophoretic device into a TGGE device. By this means we screened patients with B-cell lymphoma undergoing high-dosage radiochemotherapy followed by autologous transplantation for continuous presence of clonal (tumor-specific) CDR-III rearrangements. Specimens from blood and bone marrow were collected on diagnosis as well as before and after autologous transplantation. In addition, the autograft (bone marrow or peripheral blood hematopoietic stem cells) was analyzed. Tumor cells were easily detected in the transplants and in specimens collected during follow-up examinations. The clinical value of these findings remains unclear as yet because the number of cases investigated was small and the follow-up time is still too short. However, we conclude that the technique of combining the sensitivity of PCR with the specificity of high resolution TGGE is easy to use, making it possible to handle, in a clinical routine, a great number of samples within a short time in order to monitor MRD in patients with B-cell neoplasias.

Cell Transplantation↗
PubMed1996

Transplantation of peripheral blood progenitor cells from HLA-identical sibling donors. European Group for Blood and Marrow Transplantation (EBMT).

Transplantation of peripheral blood progenitor cells (PBPCs) has largely replaced autologous bone marrow transplantation. The same might occur in the allogeneic setting if the favourable initial experience with allogeneic PBPCT is confirmed. We analysed all primary transplants utilizing unmodified PBPC from HLA-identical sibling donors reported to the European Group for Blood and Marrow Transplantation (EBMT) for 1994. 59 patients with a median age of 39 years received myeloablative therapy for acute myelogenous leukaemia (23 patients, acute lymphoblastic leukaemia (13), chronic myelogenous leukaemia (nine), lymphoma (seven), or other diagnoses (seven) mostly of advanced stages followed by transplantation of allogeneic PBPC. Three patients died soon after grafting, the others showed prompt haemopoietic recovery with median times to recover an absolute neutrophil count (ANC) above 0.5 and 1.0 x 10(9)/I of 15 (range 9-27) and 17d (range 10-28) respectively. Time to platelet recovery above 20 or 50 x 10(9)/I was 16 (range 9-76) and 18d (range 12-100) respectively. 27 patients (46%) developed no or mild acute graft-versus-host disease (GVIID). The incidence of moderate (grade II) disease was 27%; 24% of the patients developed severe acute GVHD (grades III or IV), 55% of patients who were alive 90d after transplantation developed chronic GVHD, the probability to develop extensive chronic GVHD was 32% (95% confidence interval 22-42) with a median follow-up of 14 months. Overall and event-free survival (EFS) at 1 year were 54% (CI 48-60) and 50% (CI 43-57), respectively, the relapse incidence was 23% (CI 17-29). EFS was 67% (CI 55-79) in patients transplanted for acute leukaemias in first complete remission, chronic myelogenous leukaemia in first chronic phase, or severe aplastic anaemia. Transplantation of allogeneic PBPC resulted in prompt and durable engraftment. The incidence and severity of acute and chronic GVHD seemed comparable to that observed after allogeneic BMT. Overall and event-free survival in this cohort of patients, most of whom suffered from advanced leukaemia or lymphoma, is encouraging, suggesting that the high numbers of T lymphocytes and/or natural killer cells contained in a typical PBPC collection product exert a vigorous graft-versus-leukaemia effect. Further evaluation of allogeneic PBPCT is highly desirable.

Acute Disease↗
PubMed1996

Allogeneic peripheral blood progenitor cells: current status and future directions.

Increasing use is being made of mobilized peripheral blood as a source of hematopoietic stem and progenitor cells for transplantation. Initially, these efforts were focused on autologous applications. However, many centers are now using cells derived from normal donors mobilized with recombinant hematopoietic growth factors for allogeneic transplantation. This article reviews the key issues associated with the use of these cells for hematologic reconstitution and summarizes important recent developments in the field.

Blood Cell Count↗
PubMed1996

Significance of cytogenetic findings for the clinical outcome in patients with T-cell lymphoma of angioimmunoblastic lymphadenopathy type.

PURPOSE: The aim of this study was to evaluate the significance of cytogenetic findings for the clinical outcome of patients with Angioimmunoblastic Lymphadenopathy (AILD)-Type T-cell lymphoma. MATERIALS AND METHODS: In a retrospective analysis, the cytogenetic findings of 50 patients with AILD-type T-cell lymphoma were correlated with the frequency of spontaneous and therapy-induced remissions and with survival using the statistical methods of Kaplan and Meier and the model of Cox for multivariate analysis. Treatment was not uniform because the patients were treated in different hospitals during a period of 8 years and because a standard therapy has not yet been established. RESULTS: The following cytogenetic findings were associated with a significantly lower incidence of therapy-induced remissions and a significantly shorter survival duration: presence of aberrant metaphases in unstimulated cultures (P = .04 for both parameters); clones with an additional X chromosome (P = .0001 and P = .03, respectively); structural aberrations of the short arm of chromosome 1, preferentially involving 1p31-32 (P < .001 and P = .04, respectively); and complex aberrant clones with more than four aberrations (P = .0003 and P = .005, respectively). Multivariate analysis showed that these cytogenetic findings had a significant influence on survival, but therapy modalities did not. Only the presence of complex aberrant clones was an independent prognostic factor. Trisomy 3 had no effect on survival, but patients without trisomy 5 (P = .08) tended to live longer. CONCLUSION: This is the first study that seems to indicate that cytogenetic findings have prognostic significance in AILD-type T-cell lymphoma. These results must be proven in prospective studies of homogeneously treated patients.

Adult↗
PubMed1996

Allogeneic and autologous transplantation for haematological diseases, solid tumours and immune disorders. Current practice in Europe in 1996 and proposals for an operational classification. Accreditation Sub-Committee of the European Group for Blood and Marrow Transplantation (EBMT).

The indications and techniques employed for haematopoietic stem cell transplants performed in Europe differ substantially. The Accreditation Sub-Committee of the EBMT has consulted widely and has attempted to describe practice in Europe current in 1996 and in particular to define whether a particular procedure should be regarded as 'Routine' or whether it should be carried out preferably in the context of a Clinical Research Protocol or as part of a 'Developmental' pilot study. It is recognised that a classification of this kind must be imperfect and will require revision at frequent intervals.

Adolescent↗
PubMed1996

Randomized study of the combination of hydroxyurea and interferon alpha versus hydroxyurea monotherapy during the chronic phase of chronic myelogenous leukemia (CML Study II). The German CML Study Group.

It is the long-term goal of the German CML Study Group and of the Süddeutsche Hämoblastosegruppe (SHG) to improve survival of patients with chronic myelogenous leukemia (CML). In a first randomized study (CML Study I) monotherapies with hydroxyurea or interferon alpha (IFN-alpha) were compared with a standard busulfan regimen with regard to duration of the chronic phase and survival. The main results of this study were published, 1-3 and a long-term follow up is planned. In a second randomized study the effect of the combination of IFN-alpha and hydroxyurea versus hydroxyurea monotherapy on survival is being investigated. This paper provides a first preliminary report on the study concept, patient recruitment, state of documentation and initial patients' characteristics 9 months after closure of the study.

Adult↗
PubMed1996

High lytic activity against human leukemia cells after activation of allogeneic NK cells by IL-12 and IL-2.

IL-12 is a novel cytokine with interesting features regarding its potential usefulness in peripheral blood stem cell transplantation and leukemia immunotherapy. We used cryopreserved leukemia cells of 18 patients with acute myelogenous (n= 14) or lymphocytic (n= 4) leukemia to investigate the effect of IL-12, alone or in combination with IL-2, on the cytolytic activity of NK cells against human leukemia targets. Effector cells were peripheral blood mononuclear cells from healthy donors which were depleted from CD3+ T cells by immunomagnetic separation. CD3-negative effector cells (mainly CD56+ NK cells) were treated for 24 h with various concentrations of IL-2 (100 U/ml to 1000 U/ml) and IL-12 (1 U/ml to 100 U/ml). Cytotoxicity was measured in a 4 h 51Cr-release assay. Whereas a two-fold enhancement of cytotoxic activity was observed after incubation with optimal doses of IL-2 or IL-12, the combination of both cytokines (500 U/ml IL-2, 100 U/ml IL-12) increased the lytic activity more than six-fold. This effect was accompanied by increased expression of cellular adhesion molecules (CD2, CD18) and CD25 on CD56+ effector cells. Of 18 leukemias investigated, five were completely resistant to lysis by effector cells activated with IL-2 or IL-12 alone. In three of these five cases, however, high cytolytic activity was observed after coincubation with IL-2 and IL-12. In comparison to allogeneic NK cells, autologous cells of three patients in remission demonstrated significantly lower cytotoxic activity. No killing of nonmalignant cells (PHA blasts) by allogeneic NK cells was observed. Our data demonstrate that IL-12 can enhance or even induce MHC-unrestricted cytotoxicity of IL-2-activated allogeneic natural killer cells. Since IL-12 has also been shown to have stem-cell mobilizing capacities, it could be used for the recruitment of both stem cells and antileukemic effector cells in the context of peripheral blood stem cell transplantation.

Animals↗
PubMed1996

Comparison of anal sonography with conventional needle electromyography in the evaluation of anal sphincter defects.

OBJECTIVE: A comparison of anal sonography with conventional electromyographic mapping in the evaluation of anal sphincter defects was the aim of this study. METHODS: In 23 patients with defecatory problems referred for conventional needle electromyography (EMG), anal endosonography, with a 7.5-MHz, 355 degrees scanner, was performed before EMG to determine the structural integrity of the external anal sphincter. If lesions were found, they were described in terms of location and extent. Subsequently, concentric needle EMG of the external sphincter was performed circumferentially to locate muscle parts exhibiting normal and diminished or missing muscle activity. Lesions found by EMG were also described like those found by sonography. RESULTS: Of 23 patients, eight exhibited no abnormalities on EMG, and no muscle defects were identified endosonographically in any of these patients. In the remaining 15 patients, EMG showed either an incomplete pattern of interference or a complete absence of voluntary activity; in all of these patients endosonography also identified structural deficit. In 14 of these 15 patients, abnormalities were found at the same location with both endosonography and EMG. In the remaining patient, the two techniques identified structural and functional abnormalities at different locations. CONCLUSION: Although EMG is the gold standard for assessment of the functional relevance of muscle defects, anal endosonography yields a sensitivity and specificity of almost 100%.

Adult↗
PubMed1995

Autologous progenitor cell transplantation: prior exposure to stem cell-toxic drugs determines yield and engraftment of peripheral blood progenitor cell but not of bone marrow grafts.

Agents with stem cell-toxic potential are frequently used for salvage therapy of Hodgkin's disease (HD) and high-grade non-Hodgkin's lymphoma (NHL). Because many patients with relapsed or refractory lymphoma are candidates for autologous progenitor cell transplantation, possible toxic effects of salvage chemotherapy on progenitor cells must be taken into account. In a retrospective study, we have analyzed the influence of a salvage regimen containing the stem cell-toxic drugs BCNU and melphalan (Dexa-BEAM) on subsequently harvested bone marrow (BM)- and peripheral blood-derived progenitor cell grafts (PBPC) and compared it with other factors. Progenitor cells were collected from 96 patients with HD or high-grade NHL. Seventy-nine grafts were reinfused (35 PBPC and 44 BM) after high-dose chemotherapy. Compared with patients autografted with BM, hematopoietic recovery was significantly accelerated in recipients of PBPC. For PBPC, the number of Dexa-BEAM cycles ( > or = v > 1) was the predominate prognostic factor affecting colony-forming unit-granulocyte-macrophage (CFU-GM) yield (66 v 6.8 x 10(4)/kg, P = .0001), CD34+ cell yield (6.6 v 1.6 x 10(6)/kg, P = .0001), neutrophil recovery to > 0.5 x 10(9)/L (9 v. 11 days, P = .0086), platelet recovery to > 20 x 10(9)/L (10 v 15.5 days, P = .0002), and platelet count on day +100 after transplantation (190 v 107 x 10(9)/L, P = .031) using univariate analysis. Previous radiotherapy was associated with significantly lower CFU-GM and CD34+ cell yields but had no influence on engraftment. Patient age, patient sex, disease activity, or chemotherapy other than Dexa-BEAM did not have any prognostic impact. Multivariate analysis confirmed that Dexa-BEAM chemotherapy was the overriding factor adversely influencing CFU-GM yield (P < .0001), CD34+ cell yield (P < .0001), and platelet engraftment (P < .0001). BM grafts were not significantly affected by previous Dexa-BEAM chemotherapy or any other variable tested. However, prognostic factors favoring the use of BM instead of PBPC were not identified using joint regression models involving interaction terms between the graft type (PBPC or BM) and the explanatory variables investigated. We conclude that, in contrast to previous radiotherapy or other chemotherapy, exposure to salvage regimens containing stem cell-toxic drugs, such as BCNU and melphalan, is a critical factor adversely affecting yields and performance of PBPC grafts. Marrow progenitor cells appear to be less sensitive to stem cell-toxic chemotherapy. PBPC should be harvested before repeated courses of salvage chemotherapy involving stem cell-toxic drugs to preserve the favorable repopulation kinetics of PBPC in comparison with BM.

Adolescent↗
PubMed1995

Primary transplantation of allogeneic peripheral blood progenitor cells mobilized by filgrastim (granulocyte colony-stimulating factor)

Transplantation of allogeneic peripheral blood progenitor cells (PBPCs) may have advantages over bone marrow transplantation (BMT) with regards to the speed of hematopoietic and immunologic recovery, which may then shorten the time spent in hospital and decrease costs. The recipient might also profit by an enhanced graft-versus-leukemia reaction exerted by the high number of natural killer cells contained in such grafts. The donor could be spared the discomfort and risks of general anesthesia and marrow harvesting. Primary transplantation of unmanipulated allogeneic PBPCs has not been reported so far because the vast amount of T cells contained in the collection product was thought to cause severe graft-versus-host disease. We present preliminary data on primary transplantation of allogeneic PBPCs in patients who either suffered from advanced leukemia or had a donor unable to undergo general anesthesia. Eight patients with a median age of 42 years suffering from acute myelogenous leukemia (AML) in first remission (n = 3), AML in third remission, AML in relapse (n = 2), acute lymphoblastic leukemia in second remission, or chronic myelogenous leukemia in accelerated phase received myeloablative therapy followed by transplantation of unmanipulated allogeneic PBPCs mobilized with granulocyte colony-stimulating factor (5 to 10 micrograms/kg of body weight of filgrastim administered for 5 to 6 days) in their HLA-identical donors. Hematopoietic reconstitution was achieved in all patients with a median of 15.5 (16.5) days after transplant needed to surpass an absolute neutrophil count of 0.5 (1.0) x 10(9)/L. The median time to an unsupported platelet count greater than 20 (> 50) x 10(9)/L was 19.5 (41) days after grafting. Three patients did not exhibit signs of acute graft-versus-host disease (GVHD), grade I disease was seen in one patient, and three patients experienced grade II disease limited to the skin. The only patient with severe acute GVHD (grade III) refused to take his oral cyclosporin regularly and had ineffective serum levels for most of the time until relapse. Six of eight patients are currently alive without evidence of disease between 61 and 533 days after grafting; two patients grafted for AML in relapse achieved a complete remission after transplantation but relapsed again and died of leukemia on days +48 and +70, respectively. Primary transplantation of unmanipulated allogeneic PBPCs is feasible and results in long-term engraftment without causing detrimental GVHD.

Adolescent↗