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J Reiffers

Publications and source records attributed to J Reiffers.

At least 73 records · Page 4Linked to original sources
PubMed1999

Severe respiratory failure requiring ICU admission in bone marrow transplant recipients.

Two groups of bone marrow transplant (BMT) recipients with febrile noncardiogenic respiratory failure requiring intensive care unit (ICU) admission, in the early phase of bone marrow transplantation were compared: those who had proven infectious pneumonia and those in whom bronchoalveolar lavage (BAL) failed to establish a diagnosis. Thirty-eight consecutive neutropenic BMT recipients admitted to an ICU with febrile noncardiogenic respiratory failure were enrolled. All of them underwent a BAL with viral, fungal, bacterial, and histopathological examinations. Lung biopsies were performed in nonsurviving patients in order to compare with BAL results. Haematological, biological, respiratory failure and other organ failure parameters, infectious results, outcome, and lung biopsy results were evaluated. BAL allowed an infectious diagnosis to be established in 16 BMT recipients. No aetiology was proven in 22 patients. Without a significant difference in respiratory failure parameters on ICU admission, noninvasive continuous positive airway pressure ventilation, which was given to 11 patients in each group, was significantly more successful in patients with proven infectious pneumonia (6 of 11 versus 0 of 11 patients) and enabled endotracheal intubation to be avoided in significantly more patients with infectious disease (10 of 16 versus 22 of 22 patients). The evolution of patients without diagnosis was significantly different with more frequent renal failure, hepatic failure, and death (20 of 22 versus 9 of 16 patients). Post mortem biopsies confirmed the absence of micro-organisms, but endothelial damage and fibrosis was found in 14 of the 22 patients. In conclusion, in the early phase of bone marrow transplantation the recipients without proven aetiology of pneumonia have a worse outcome than grafted patients with proven infectious pneumonia.

Adult↗
PubMed1999

Autologous stem cell transplantation in chronic myeloid leukemia: a single center experience.

Between 1980 and 1996, we transplanted 72 patients with CML using blood stem cells collected at diagnosis before treatment and without any mobilization. The median age of patients at diagnosis was 47.5 years (range 20.5-59.5). The median numbers of nucleated cells and CFU-GM transplanted were 10 x 10(8)/kg and 97 x 10(4)/kg, respectively. The median duration to reach more than 0.5 x 10(9)/l neutrophils and 50 x 10(9)/l platelets was 12 (range 5-19) and 11 days (range 0-79), respectively. Twenty patients (group I) were transplanted in chronic phase either for resistance to IFN (14 patients) (group IA) or because the Sokal index was more than 1.2 (six patients) (group IB). All those patients had preparative regimen with busulfan (4 mg/kg/day x 4) and melphalan (140 mg/m2). They were treated with recombinant alpha-interferon (IFN) after transplant. The cumulative incidence of major cytogenetic response (MCR) at 12 months was 25 +/- 21% (95% CI), the 5-year survival was 75 +/- 42% (95% CI). These results (observed in patients with bad prognosis factors) are similar to those usually observed in CML patients treated by IFN, whatever the Sokal risk. Thus autologous transplantation is able to reproduce for poor prognosis patients the results observed in standard risk patients treated with IFN. This suggests that it could prolong survival. Fifty-two other patients (group II) were transplanted for CML in transformation (accelerated phase = 32; blast crisis = 20) after a preparative regimen containing either total body irradiation (TBI) or busulfan. The median survival was short (10.4 months) and only 21 patients survived more than 1 year. The survival was longer for patients transplanted in accelerated phase (vs blast crisis), those who were due to receive a double transplant (vs single) (34 patients), those who were treated with IFN after transplant (vs hydroxyurea) and for the patients who obtained a complete hematologic response.

Adult↗
PubMed1999

Chronic myeloid leukemia in first chronic phase not responding to alpha-interferon: outcome and prognostic factors after autologous transplantation. EBMT Working Party on Chronic Leukemias.

We report the data obtained from the European Bone Marrow Transplant Registry for patients with CML who received autologous transplantation (AT) in chronic phase (CP) because alpha-IFN was ineffective. Forty-one CML patients (median age: 40.5 years; median Sokal index: 0.78) were included in this study. Bone marrow (16 cases) or blood (25 cases) progenitor cells were collected at diagnosis in 19 patients, during stable chronic phase or while the patient had cytogenetic (Cy) or complete hematologic response (CHR) in the other 22, and were manipulated ex vivo in 10 cases. The conditioning regimen consisted of busulfan associated with other chemotherapeutic regimens in 36 cases. Two patients died from interstitial pneumonitis (one case) and hemorrhage (one case). From the date of AT, the estimated probability of survival for the 41 patients was 84 +/- 13% and 51 +/- 29% at 2 and 4 years, respectively. Considering the 39 evaluable patients, the actuarial probability of achieving CHR, major and complete CyR 2 years after AT was 92 +/- 9%, 46 +/- 17%, and 30 +/- 15%, respectively. The Sokal score at diagnosis and the achievement of hematologic response after transplant were of prognostic importance. We suggest that a significant proportion of CML patients not responding to alpha-IFN may benefit from AT.

Adolescent↗
PubMed1999

Allogeneic bone marrow transplant or second autograft in patients with acute leukemia who relapse after an autograft. Acute Leukaemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT).

Among 2752 patients with acute leukemia who had recurrent leukemia after autograft in remission and were reported to the EBMT, 94 underwent an allogeneic bone marrow transplant and 74 received a second autograft. Recipients of HLA-mismatched related or unrelated bone marrow had an increased transplant-related mortality (TRM, P = 0.017) and a decreased leukemia-free survival (LFS, P = 0.03), compared to recipients of HLA matched related or unrelated bone marrow. Outcome in recipients of HLA-compatible related or unrelated bone marrow was compared to those receiving a second autograft. TRM at 2 years was 51 +/- 8% in recipients of matched allografts and 26 +/- 6% following a 2nd autograft (P < 0.05). Two-year LFS was 27 +/- 7% and 35 +/- 6% in the two groups, respectively (NS). Multivariate analysis in these two groups showed that TRM was increased in patients who were in 2nd or later remission at 1st autograft (P < 0. 05) and allograft recipients (P < 0.05). Relapse was more common in patients with ALL (P < 0.001), above 25 years of age (P < 0.02), autograft performed later than 1991 (P < 0.05), and in second autografts (P < 0.05). LFS was decreased in patients >25 years of age (P < 0.01), if the interval from first autograft to relapse was 8 months or less (P < 0.01) and if TBI was used at first autograft (P < 0.05).

Adolescent↗
PubMed1999

Syngeneic transplantation in multiple myeloma - a case-matched comparison with autologous and allogeneic transplantation. European Group for Blood and Marrow Transplantation.

Twenty-five patients with multiple myeloma received bone marrow grafts (n = 24) or peripheral blood stem cells (n = 1) from twin donors. The outcome was compared in a case-matched analysis to 125 patients who underwent autologous transplantation, and 125 who underwent allogeneic transplantation. Seventeen patients (68%) receiving twin transplants entered complete remission, which was not significantly different from that of autologous (48%) or allogeneic (58%) transplants. The median overall and progression-free survival for the twins was 73 and 72 months, respectively. The overall survival tended to be better (73 vs 44 months) and the progression-free survival was significantly better (72 vs 25 months) than with autologous transplantation and both were significantly better than with allogeneic transplantation. Three of 17 patients who entered complete remission following transplantation had relapsed at follow-up. This relapse rate was significantly lower than following autologous transplantation and similar to the relapse rate with allogeneic transplantation. Only two twins died of transplant-related toxicity. Six further patients died of progressive or relapsing disease. Syngeneic transplantation in multiple myeloma appears to be the treatment of choice if a twin donor is available. A lower relapse risk than in autotransplantation may be due to reinfusion of malignant cells in some patients treated with this modality or to the presence of a graft-versus-myeloma effect in some syngeneic transplants.

Adult↗
PubMed1999

Transgene expression, but not gene delivery, is improved by adhesion-assisted lipofection of hematopoietic cells.

In contrast to adherent cells, cells growing in suspension and particularly hematopoietic cells, are notoriously difficult to transfect in vitro using nonviral approaches. In the present study, the effect of cell adhesion on gene transfer efficacy was investigated by allowing hematopoietic cells to bind to an adherent cell monolayer (ACM) before being subjected to cationic liposome-mediated DNA transfer. Human CD34 and T CD4 cell lines were cultivated on an ACM constituted of murine fibroblast NIH3T3 cells and transfected with a plasmid carrying the beta-galactosidase gene. X-gal staining showed that up to 27% of the cells expressed the transgene. In contrast, less than 0.1% of these cells were positively transfected in suspension. This adhesion-assisted lipofection (AAL) procedure was also successfully tested on blood lymphocytes, since it resulted in up to 30% of transfected human primary T lymphocytes. Flow cytometry analysis performed on T lymphocyte subsets revealed that 8 and 9%, respectively, of CD4 and CD8 cells could be transfected with a plasmid carrying the green fluorescent protein gene. Other adherent cells, such as MS5 murine stromal cells or HeLa epithelial cells, were also a compatible matrix for AAL. Moreover, the pCMV beta plasmid was present in similar amounts in the nuclei of TF1 cells transfected in suspension or with the AAL procedure. These data raise the possibility that cell matrix/hematopoietic cell interactions might govern expression of the transgene in hematopoietic cells growing usually in suspension, but not endocytosis of liposome/DNA particles and plasmid migration ot the cell nucleus.

3T3 Cells↗
PubMed1999

A novel immunodeficient mouse model--RAG2 x common cytokine receptor gamma chain double mutants--requiring exogenous cytokine administration for human hematopoietic stem cell engraftment.

Gene transduction into immature human hematopoietic cells collected from umbilical cord blood, bone marrow, or mobilized peripheral blood cells could be useful for the treatment of genetic and acquired disorders of the hematopoietic system. Immunodeficient mouse models have been used frequently as recipients to assay the growth and differentiation of human hematopoietic stem/progenitor cells. Indeed, high levels of human cell engraftment were first reported in human/murine chimeras using NOD/SCID mice, which now are considered as the standard for these types of experiments. However, NOD/SCID mice have some clear disadvantages (including spontaneous tumor formation) that limit their general use. We have developed a new immunodeficient mouse model by combining recombinase activating gene-2 (RAG2) and common cytokine receptor gamma chain (gamma c) mutations. The RAG2-/-/gamma c- double mutant mice are completely alymphoid (T-, B-, NK-), show no spontaneous tumor formation, and exhibit normal hematopoietic parameters. Interestingly, human cord blood cell engraftment in RAG2-/-/gamma c- mice was greatly enhanced by the exogenous administration of human cytokines interleukin-(IL-3) granulocyte-macrophage colony-stimulating factor, (GM-CSF), and erythropoietin in contrast to the NOD/SCID model. This unique feature of the RAG2-/-/gamma c- mouse model should be particularly well suited for assessing the role of different cytokines in human lymphopoiesis and stem/progenitor cell function in vivo.

Animals↗
PubMed1999

Automated reticulocyte counting and immature reticulocyte fraction measurement. Comparison of ABX PENTRA 120 Retic, Sysmex R-2000, flow cytometry, and manual counts.

We evaluated reticulocyte counting and measurement of immature reticulocyte fraction (IRF) with the ABX PENTRA 120 Retic blood analyzer on 300 blood samples. Reticulocyte counts were compared with those obtained by visual counting of 2,000 RBCs, by the TOA (Kobe, Japan) Sysmex R-2000 and a flow cytometry method. The parameters analyzed were the percentages of reticulocytes on all analyzers and the IRF with different modalities. The Retic Count kit (Becton Dickinson, San Jose, CA) was used with the Coulter (Hialech, FL) XL, and a mean channel of fluorescence (MCF) was calculated to fit the reticulocyte maturation. Reticulocyte counting with the ABX (Montpellier, France) PENTRA 120 Retic showed excellent precision and linearity with no significant carryover. Reticulocyte counts were stable after blood storage for 72 hours at 4 degrees C but not at room temperature (RT). IRF parameters values were stable for only 8 hours at 4 degrees C and 6 hours at RT. Comparisons of the methods showed good intraclass correlation (RI) for reticulocyte percentages between ABX PENTRA 120 Retic and Sysmex R-2000, ABX PENTRA 120 Retic and flow cytometry, Sysmex R-2000 and flow cytometry, and ABX PENTRA 120 Retic and manual counting. IRF values were correlated between fluorescence rates and RNA content, but in each case, low RI values were found, showing that Sysmex and ABX IRF values were not concordant. We obtained a significant correlation between mean fluorescence index and the MCF measured by flow cytometry, but the 2 methods were not concordant using the RI. The ABX PENTRA 120 Retic is a good instrument for analyzing reticulocyte count and percentage and allows a good analysis of IRF with several modalities.

Acute Disease↗
PubMed1999

Expansion and differentiation of haemopoietic progenitor cells on endothelialized hydroxyapatite under static conditions.

We have analysed the potential of an endothelialized hydroxyapatite matrix (HAP), a synthetic bone substitute, as a cellularized support for the expansion of haemopoietic progenitor cells. Scanning electron microscopy (SEM) showed that the endothelial cells (EC) tended to form a monolayer fitting closely to the matrix, and that the progenitors adhered to the EC layer. Endothelialized HAP supported the proliferation and differentiation of the progenitors with the addition of the exogenous cytokines IL-1, and IL-3. The expanded cell population essentially belonged to the myeloid and monocytic lineages, with a smaller percentage of the megakaryocyte lineage. In comparative experiments CD34+ progenitors were expanded on endothelialized tissue culture flasks, and a significant higher viability of the expanded cells was found with the endothelialized HAP. A high percentage (approx. 40%) of mature granulocytes was generated in accordance with the presence of differentiating cytokines such as G-CSF and GM-CSF at high concentrations in the coculture medium. Other cytokines that could be detected were IL-6, M-CSF, SCF, flt3-ligand. More than 50% of the expanded cell population was able to phagocytose bacteria and to generate an oxydative burst. These data indicate that cellularized HAP may be a useful matrix for stromal cell-based expansion systems.

Cell Differentiation↗
PubMed1998

Response at three months is a good predictive factor for newly diagnosed chronic myeloid leukemia patients treated by recombinant interferon-alpha.

In a single institution, we have used recombinant interferon- (IFN-) to treat 116 newly diagnosed Philadelphia-positive (Ph+) chronic myeloid leukemia (CML) patients and analyzed the predictive factors for response and survival. The patients whose median age was 50.3 years (range, 9 to 70) were administered IFN- (5 million units/m2/d) subcutaneously. The IFN- dose was subsequently adjusted to maintain the white blood cell and platelet counts between 1.5 and 5 x 10(9)/L, 50 and 100 x 10(9)/L, respectively. At diagnosis, the Sokal score was used to classify the patients into three groups: low (n = 57), intermediate (n = 42), and high risk (n = 16). A complete hematological response (CHR) was achieved in 93 cases (80.2%). Of the 116 patients, 113 were available for cytogenetic evaluation. Fifty patients (43%) achieved a major cytogenetic response (MCR) (=65% marrow Ph- cells), 37 of them having a complete cytogenetic response (CCR). The estimated 5-year survival of the 116 patients was 68% +/- 11% (95% confidence interval [CI]) with a median follow-up of 42 months (range, 3 to 114) and 85% +/- 11% (95% CI) with a median follow-up of 30.9 (range, 3 to 111) when patients were censored at the time of transplantation. Event-free survival at 5 years (adding death and transplant as event) was 46% +/- 11% (95% CI). Using proportional hazards regression to study time-dependent variables, we confirmed that the most significant factor associated with survival was the cytogenetic response (MCR or CCR) (P <.0001). This factor was independent compared with the Sokal score and baseline variables used to calculate the Sokal score. Moreover, using either univariate or multivariate analysis, the achievement of CHR within 3 months was strongly correlated with MCR (P <.0001). Minimum cytogenetic response (mCR, ie, at least 5% of Ph- metaphases) at 3 months was also a significant predictive factor for MCR (P <.0001). These results show that IFN- can induce a high rate of hematological and cytogenetic response when administered in doses leading to myelosuppression. Factors such as the achievement of CHR and mCR within 3 months could be useful to identify early those patients who will not respond to IFN- and who need alternative treatments such as stem cell transplantation.

Administration, Cutaneous↗
PubMed1998

Fluorescent in situ hybridization on flow-sorted cells as a tool for evaluating minimal residual disease or chimerism after allogenic bone marrow transplantation.

We studied the feasibility and the sensitivity of fluorescent in situ hybridization (FISH) using leukemic or host/donor-specific probes on flow-sorted cells to assess minimal residual disease (MRD) or chimerism in transplanted patients in complete remission. We first performed experimental models of MRD and chimerism by mixing HL60 cells and normal lymphocytes in different proportions. Over 80% HL60 cells were obtained from mixtures of 5% HL60 cells in peripheral blood mononuclear cells (PBMC). We then evaluated MRD and mixed chimerism in a chronic myelogenous leukemia patient in relapse after allogeneic sex-mismatched bone marrow transplantation (BMT), who had received a donor lymphocyte infusion (DLI). Three months after DLI, mixed chimerism was observed in each bone marrow (BM)-sorted lineage (CD13+, CD14+, CD20+, and CD3+), with the highest level of recipient cells in the granulocytic lineage (CD13+). Five months after DLI, host cells were at a low level but remained detectable in the granulocytic lineage. In the same sample, the bcr-abl gene was detected in the granulocytic lineage and not in the lymphocytes. We also studied chimerism in an aplastic anemia sex-mismatched transplanted female patient. We determined the proportion of recipient total lymphocytes, CD4+ and CD8+ lymphocytes, and CD14+ monocytes under cyclosporin A therapy on five peripheral blood samples and one BM sample over 5 months. Results showed a regular decrease in recipient total lymphocytes (26.6% to 10.6%) and monocytes (20.7% to 8%). CD8(+)-recipient cells decreased rapidly, while CD4+ remained stable (17%). This work demonstrates the feasibility of FISH after cell sorting, combining the sensitivities of both flow cytometry and FISH and the specificities of both immunophenotyping and genotype analysis.

Anemia, Aplastic↗
PubMed1998

Allogeneic bone marrow transplantation for low-grade lymphoma.

Advanced low-grade lymphomas are usually incurable with conventional-dose chemotherapy. It is uncertain whether cures are possible with high-dose therapy and bone marrow transplant from a human leukocyte antigen (HLA)-identical sibling. We sought to determine the outcome of HLA-identical sibling bone marrow transplants in advanced low-grade lymphoma in an observational study of 113 patients conducted at 50 centers participating in the International Bone Marrow Transplant Registry (IBMTR). The median patient age was 38 years (range, 15 to 61). Eighty percent had stage IV disease at the time of transplantation. The median number of prior chemotherapy regimens was two (range, 0 to 5). Thirty-eight percent had refractory disease and 29% a Karnofsky performance score (KPS) less than 80%. All patients underwent allogeneic bone marrow transplantation from a HLA-identical sibling donor. The conditioning regimen included total-body irradiation (TBI) in 82% of patients; cyclosporine was used for graft-versus-host disease prophylaxis in 74%. Survival, disease-free survival, recurrence rate, treatment-related mortality, and causes of death were determined. Three-year probabilities of recurrence, survival, and disease-free survival were 16% (95% confidence interval [CI], 9% to 27%), 49% (95% CI, 39% to 60%), and 49% (95% CI, 39% to 59%), respectively. Higher survival was associated with pretransplant KPS >/=90%, chemotherapy-sensitive disease, use of a TBI-containing conditioning regimen, and age less than 40 years. We conclude that high-dose therapy followed by transplantation from a HLA-identical sibling leads to prolonged survival in some patients with advanced low-grade lymphoma. Most mortality is treatment-related, and recurrences are rare.

Adolescent↗
PubMed1998

Caspase activation is an early event in anthracycline-induced apoptosis and allows detection of apoptotic cells before they are ingested by phagocytes.

An increasing number of methods are being described to detect apoptotic cells. However, attempts to detect apoptotic cells in clinical samples are rarely successful. A hypothesis is that apoptotic cells are cleared from the circulation by phagocytosis before they become detectable by conventional morphological or cytometric methods. Using LR73 adhering cells as phagocytes in a model of in vitro phagocytosis, we found that phagocytosis of daunorubicin (DNR)-treated U937, HL60, or K562 leukemia cell lines occurred prior to phosphatidylserine externalization, DNA hydrolysis, chromatin condensation, nuclear fragmentation, or mitochondrial potential alteration. Moreover DNR-treated K562 cells were eliminated by phagocytes while apoptosis was never observed by any of the above methods. By contrast, using a fluorometric batch analysis assay to detect caspase activity in ceramide- or DNR-treated cells (fluorogenic substrate for caspase), we found that caspase activity increased in apoptosis-committed cells before they were detected by flow cytometry or recognized by phagocytes. Similarly a caspase activity increase was detected in circulating mononuclear cells of luekemic patients 15 h after the beginning of anthracyclin treatment. We suggest that recent findings on enzymatic events (caspase activation) occurring in the early events of apoptosis must now allow the development of new markers for apoptosis, irrespective of the morphological features or internucleosomal fragmentation which are late events in apoptosis.

Animals↗
PubMed1998

Stable mixed chimerism without relapse after related allogeneic umbilical cord blood transplantation in a child with severe aplastic anemia.

Umbilical cord blood (UCB) cells from HLA-matched donors are used as an alternative to bone marrow for allogeneic transplantation and reports of successful UCB transplantation in patients with severe aplastic anemia (SAA) are scarce. SAA was discovered in a 4-year-old girl in February 1990. Transfusion support started in August 1990 and standard treatments were unsuccessful. The birth of an HLA-compatible brother in October 1993 permitted the cryopreservation of UCB. In December 1994 UCB transplantation was decided upon. No toxicity occurred. G-CSF was started at day 28. WBC and PMN reached 0.5 x 10(9)/l at days 33 and 37. RBC and platelet transfusion independence were reached at days 50 and 52. Mixed chimerism was demonstrated in blood cells at 1.5, 4 and 6 months after UCBT by molecular biology (VNTR). FISH studies yielded similar results at 15 and 18 months. Twenty months after UCBT, molecular biology showed full donor chimerism. Clinical follow-up (last follow-up: 32 months post transplant) is unremarkable. We suggest that CY and ATG may be a suitable regimen for related HLA-compatible UCBT in patients with SAA. Residual recipient cells can disappear even very late after UCBT, permitting the establishment of complete donor chimerism.

Anemia, Aplastic↗
PubMed1998

Factors influencing haemopoietic recovery following chemotherapy-mobilised autologous peripheral blood progenitor cell transplantation for haematological malignancies: a retrospective analysis of a 10-year single institution experience.

We retrospectively analysed the factors that influenced rate of haemopoietic recovery (HR) in 243 patients after transplantation with chemotherapy-mobilised autologous peripheral blood progenitor cells (PBPC). Approximately half the patients also received haemopoietic growth factors (HGF) for mobilisation. Conditioning for transplantation was with either chemotherapy alone or chemotherapy plus total body irradiation (TBI). Median time to recovery of granulocytes > or = 0.5 x 10(9)/l was 13 days (range 7-93 days) and of platelets > or = 50 x 10(9)/l 14 days (7-440). Speed of HR was greater, both for neutrophils and platelets for patients who received more rather than less CFU-GM than our median value of 18.9 x 10(4)/kg (P < 0.0001 in both instances) and more rather than less CD34-positive cells than our median value of 8.8 x 10(6)/kg (P < 0.0001 and P < 0.0005, respectively). For granulocyte recovery, in the multivariate analysis the dose of infused CFU-GM (P = 0.05) and the use of HGF for both mobilisation and post-transplantation (P < 0.0014) were significant positive factors. For platelet recovery in the multivariate analysis the dose of infused CFU-GM (P < 0.0016) was a positive factor. The use of busulphan and of TBI were significant adverse factors for rate of platelet recovery (P = 0.005 and 0.0004, respectively). When compared with non-HGF-mobilised PBPC, HGF-mobilised PBPC reduced the number of days of hospitalisation (28 vs 24, P = 0.0001) and of treatment with intravenous antibiotics (15 vs 11, P = 0.0004). These findings emphasise the importance of cell dose in accelerating haemopoietic recovery after autologous blood stem cell transplantation.

Adolescent↗