PubMed Health⌕ Search

Biomedical subjects

W E Fibbe

Publications and source records attributed to W E Fibbe.

At least 37 records · Page 2Linked to original sources

Intensive immunosuppression and autologous stem cell transplantation for patients with severe rheumatoid arthritis: the Leiden experience.

Ten patients with active, destructive rheumatoid arthritis refractory to antirheumatic therapy enrolled in a study to evaluate the effects of intensive immunosuppression followed by autologous stem cell transplantation. Intensive immunosuppression was achieved with high dose cyclophosphamide as part of the mobilization (4 g/m2) and conditioning (200 mg/kg) regimen. The autologous stem cell products were enriched for CD34+ cells to minimize the chance of reinfusing autoreactive lymphocytes. Eight patients completed all consecutive treatment steps, one patient withdrew after mobilization because of improvement, one patient was taken off study because of pulmonary embolism. The treatment appeared feasible and safe, and marked sustained clinical improvement was observed in 6 patients, 2 of whom were previously unresponsive to tumor necrosis factor blocking therapy. In 5 patients disease modifying antirheumatic drugs were successfully withdrawn after transplantation. The treatment induced significant lymphopenia, with low levels of naive CD4+ T cells in particular, without clinical sequelae. Titers of rheumatoid factor dropped but did not normalize.

Adult↗

The role of metalloproteinases and adhesion molecules in interleukin-8-induced stem-cell mobilization.

The chemokine interleukin-8 (IL-8) is a potent chemoattractant and activator of neutrophils. Upon systemic injection, IL-8 induces an immediate neutropenia followed by a rebound granulocytosis. In this report, we discuss the effects of IL-8 on the mobilization of hematopoietic stem cells. Within 20 minutes following a single intraperitoneal injection in mice, IL-8 induces the mobilization of hematopoietic progenitor cells (HPC) with colony-forming, radioprotective, and long-term lymphomyeloid resubpopulating ability. Mobilization can be specifically prevented by pretreatment with antibodies against the beta2 integrin LFA-1 (CD11a). In monkeys, IL-8 Induces the rapid release of the metalloproteinase gelatinase-B concurrent with the mobilization of HPC. The latter effect can be prevented by blocking gelatinase-B activity using specific monoclonal antibodies, suggesting the involvement of gelatinase-B as a mediator of HPC mobilization. These results are consistent with the hypothesis that neutrophils are major regulators of stem-cell mobilization through the release of metalloproteinases (MMPs) that cleave extracellular matrix molecules to which HPC are attached.

Animals↗

Analysis of gene expression in subpopulations of murine hematopoietic stem and progenitor cells.

OBJECTIVE: The aim of the present work was to study how functional differences between subsets of the murine hematopoietic stem/progenitor cell compartment are manifested on the level of different patterns of gene expression in these subsets. MATERIALS AND METHODS: Amplified 3' terminal total cDNA fragment populations from four stem and progenitor cell fractions sorted using differential staining with Rhodamine 123 were prepared, and gene expression patterns were analyzed by Southern hybridization with a panel of gene markers. RESULTS: For the vast majority of lineage-specific markers, no expression was detected in the long-term repopulating stem cell fraction. Expression of a number of key genes positively regulating entry and progression through the cell cycle was down-regulated in long-term repopulating cells, in accordance with the quiescent state of the latter. In contrast, certain but not all cell division kinase inhibitors were significantly up-regulated in long- and short-term repopulating stem cell fractions. Expression of several genes important for entry into the apoptotic pathway was moderately reduced in long-term repopulating cells. Messenger RNA levels of the transcription factors GATA-1, GATA-2, c-Myb and SCL were down-regulated in long-term repopulating cells, as compared to more mature stem/progenitor cells. Finally, expression of the MDR1a gene encoding the Pgp efflux pump was highest in long-term repopulating cells, and progressively decreased with maturation. CONCLUSION: The patterns of gene expression in the stem/progenitor cell fractions are in good correlation with the known properties of adult hematopoietic stem/progenitor cells and may provide insight into molecular mechanisms underlying stem cell physiology.

Animals↗

CD52 antibodies for prevention of graft-versus-host disease and graft rejection following transplantation of allogeneic peripheral blood stem cells.

Graft-versus-host disease (GVHD) is a major cause of mortality and morbidity after allogeneic bone marrow transplantation, but can be avoided by removing T lymphocytes from the donor bone marrow. However, T cell depletion increases the risk of graft rejection. In this study, two strategies are used to overcome rejection: (1) use of high doses of stem cells obtained from peripheral blood (PBSC), (2) admixture with a CD52 monoclonal antibody in order to deplete both donor and residual recipient lymphocytes. Two antibodies are compared: CAMPATH-1G (rat IgG2b) and its humanized equivalent CAMPATH-1H (human IgG1). A total of 187 consecutive patients at six centers received PBSC transplants from HLA-matched siblings between 1997 and 1999. A wide spectrum of diseases, both malignant and non-malignant, was included. The recovery of CD34+ cells after antibody treatment was close to 100%. The risk of acute GVHD (grade 2 to 4) was 11% in the CAMPATH-1G group and 4% in the CAMPATH-1H group (P = NS). The risk of chronic GVHD (any grade) was 11% in the CAMPATH-1G group and 24% in the CAMPATH-1H group (P = 0.03) but the risk of extensive chronic GVHD was only 2%. The overall risk of graft failure/rejection was 2%, not significantly different between the two antibodies. Antibody treatment was equally effective at concentrations between 10 microg/ml and 120 microg/ml and it made no significant difference to the outcome whether the patients received post-transplant immunosuppression or not (87% did not). Transplant-related mortality in this heterogenous group of patients (including high-risk and advanced disease) was 22% at 12 months. It is proposed that treatment of peripheral blood stem cells with CAMPATH-1H is a simple and effective method for depleting T cells which may be applicable to both autologous and allogeneic transplants from related or unrelated donors. Special advantages of this approach are the simultaneous depletion of donor B cells (which reduces the risk of EBV-associated lymphoproliferative disease) and the concomitant infusion of CAMPATH-1H to deplete residual recipient T cells and thus prevent graft rejection.

Alemtuzumab↗

Prevention of interleukin-8-induced mobilization of hematopoietic progenitor cells in rhesus monkeys by inhibitory antibodies against the metalloproteinase gelatinase B (MMP-9).

Previously, we demonstrated that IL-8 induces rapid mobilization of hematopoietic progenitor cells (HPC) from the bone marrow of rhesus monkeys. Because activation of neutrophils by IL-8 induces the release of gelatinase B (MMP-9), which is involved in the degradation of extracellular matrix molecules, we hypothesized that MMP-9 release might induce stem cell mobilization by cleaving matrix molecules to which stem cells are attached. Rhesus monkeys were treated with a single i.v. injection of 0.1 mg/kg human IL-8, which resulted in a 10- to 100-fold increase in HPC within 30 min after injection. Zymographic analysis revealed a dramatic instantaneous increase in the plasma levels of MMP-9, followed by the increase in circulating HPC. Enzyme levels decreased at 2 h after injection of IL-8, simultaneously with the decrease in the numbers of circulating HPC. To test the hypothesis that MMP-9 induction was involved in HPC mobilization, rhesus monkeys were treated with a highly specific inhibitory monoclonal anti-gelatinase B antibody. Anti-gelatinase B at a dose of 1-2 mg/kg completely prevented the IL-8-induced mobilization of HPC, whereas a dose of 0.1 mg/kg had only a limited effect. Preinjection of inhibitory antibodies did not preclude the IL-8-induced production and secretion of MMP-9. Pretreatment with an irrelevant control antibody did not affect IL-8-induced mobilization, showing that the inhibition by the anti-gelatinase B antibody was specific. In summary, IL-8 induces the rapid systemic release of MMP-9 with concurrent mobilization of HPC that is prevented by pretreatment with an inhibitory anti-gelatinase B antibody, indicating that MMP-9 is involved as a mediator of the IL-8-induced mobilization of HPC.

Animals↗

Complete remission of accelerated phase chronic myeloid leukemia by treatment with leukemia-reactive cytotoxic T lymphocytes.

Relapse of chronic myeloid leukemia (CML) in chronic phase after allogeneic stem cell transplantation (SCT) can be successfully treated by donor lymphocyte infusion (DLI). However, relapse of accelerated phase CML, blast crisis, or acute leukemia after allogeneic SCT are resistant to DLI in the majority of cases. In vitro-selected and expanded leukemia-reactive T-cell lines may be more effective in inducing an antileukemic response in vivo. To treat a patient with accelerated phase CML after allogeneic SCT, leukemia-reactive cytotoxic T-lymphocyte (CTL) lines were generated from her HLA-identical donor. Using a modification of a limiting dilution assay, T cells were isolated from the donor, selected based on their ability to inhibit the in vitro growth of CML progenitor cells, and subsequently expanded in vitro to generate CTL lines. Three CTL lines were generated that lysed the leukemic cells from the patient and inhibited the growth of leukemic progenitor cells. The CTL did not react with lymphocytes from donor or recipient and did not affect donor hematopoietic progenitor cells. The 3 leukemia-reactive CTL lines were infused at 5-week intervals at a cumulative dose of 3.2 x 10(9) CTL. Shortly after the third infusion, complete eradication of the leukemic cells was observed, as shown by cytogenetic analysis, fluorescence in situ hybridization, molecular analysis of BCR/ABL-mRNA, and chimerism studies. These results show that in vitro cultured leukemia-reactive CTL lines selected on their ability to inhibit the proliferation of leukemic progenitor cells in vitro can be successfully applied to treat accelerated phase CML after allogeneic SCT.

Adult↗

Biology of IL-8-induced stem cell mobilization.

The CXC chemokine interleukin-8 (IL-8) has profound hematopoietic activities following systemic administration. It induces the rapid mobilization of cells with lymphomyeloid repopulating ability in mice and of hematopoietic progenitor cells in monkeys. In this paper, evidence is presented that stem cell mobilization in mice requires the functional expression on the beta 2-integrin leukocyte function-associated antigen-1 (LFA-1). In monkeys, systemic injection of IL-8 is followed by a significant increase in the circulating levels of the matrix metallo proteinase gelatinase-B (MMP-9). Based on these findings, the hypothesis is discussed that mature neutrophils serve as intermediate cells in IL-8-induced stem cell mobilization by the release of proteinases.

Animals↗

Serum transforming growth factor-beta1 levels in bone marrow transplant recipients correlate with blood cell counts and chronic graft-versus-host disease.

OBJECTIVE: Profound immunosuppression and extensive fibrotic changes in the skin are characteristic for graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (BMT). Transforming growth factor (TGF)-beta is a potent immunosuppressive cytokine that plays an important regulatory role in the immune response. In addition, TGF-beta promotes wound repair but has also been implicated in tissue fibrosis. These characteristics prompted us to question whether serum TGF-beta levels would be associated with GVHD after BMT. METHODS: In this study, total TGF-beta1 levels in serum from HLA-identical BMT recipients before and at several time intervals after transplantation were quantified and correlated with platelet and white blood cell (WBC) counts and with the presence of acute and chronic GVHD in a multivariate analysis. RESULTS: TGF-beta1 levels were readily detectable in healthy controls and in BMT recipients before BMT. In all patients, a rapid drop in TGF-beta1 levels was seen during the BMT conditioning regimen. After 20-50 days postBMT, TGF-beta1 levels started to increase to normal levels. Platelet and WBC counts were strongly correlated with TGF-beta1 levels (r=0.810, P<0.001, and r=0.733, P<0.001, respectively). Multivariate analysis also revealed that TGF-beta1 levels were significantly increased during chronic GVHD and that the increase during acute GVHD reached levels of significance (P=0.009 and P=0.053, respectively). CONCLUSIONS: These results show that total TGF-beta1 levels correlate significantly with platelet and WBC counts and that chronic GVHD is associated with an increase in serum TGF-beta1, independent of platelet or WBC counts.

Adult↗

Murine hematopoietic progenitor cells with colony-forming or radioprotective capacity lack expression of the beta 2-integrin LFA-1.

Recently, we have demonstrated that antibodies that block the function of the beta2-integrin leukocyte function-associated antigen-1 (LFA-1) completely abrogate the rapid mobilization of hematopoietic progenitor cells (HPC) with colony-forming and radioprotective capacity induced by interleukin-8 (IL-8) in mice. These findings suggested a direct inhibitory effect of these antibodies on LFA-1-mediated transmigration of stem cells through the bone marrow endothelium. Therefore, we studied the expression and functional role of LFA-1 on murine HPC in vitro and in vivo. In steady state bone marrow +/- 50% of the mononuclear cells (MNC) were LFA-1(neg). Cultures of sorted cells, supplemented with granulocyte colony-stimulating factor (G-CSF)/granulocyte-macrophage colony-stimulating factor (GM-CSF)/IL-1/IL-3/IL-6/stem cell factor (SCF) and erythropoietin (EPO) indicated that the LFA-1(neg) fraction contained the majority of the colony-forming cells (CFCs) (LFA-1(neg) 183 +/- 62/7,500 cells v LFA-1(pos) 29 +/- 17/7,500 cells, P <.001). We found that the radioprotective capacity resided almost exclusively in the LFA-1(neg) cell fraction, the radioprotection rate after transplantation of 10(3), 3 x 10(3), 10(4), and 3 x 10(4) cells being 63%, 90%, 100%, and 100% respectively. Hardly any radioprotection was obtained from LFA-1(pos) cells. Similarly, in cytokine (IL-8 and G-CSF)-mobilized blood, the LFA-1(neg) fraction, which comprised 5% to 10% of the MNC, contained the majority of the colony-forming cells, as well as almost all cells with radioprotective capacity. Subsequently, primitive bone marrow-derived HPC, represented by Wheat-germ-agglutinin (WGA)+/Lineage (Lin)-/Rhodamine (Rho)- sorted cells, were examined. More than 95% of the Rho- cells were LFA-1(neg). Cultures of sorted cells showed that the LFA-1(neg) fraction contained all CFU. Transplantation of 150 Rho- LFA-1(neg) or up to 600 Rho-LFA-1(pos) cells protected 100% and 0% of lethally irradiated recipient mice, respectively. These results show that primitive murine HPC in steady-state bone marrow and of cytokine-mobilized blood do not express LFA-1.

Animals↗

Parenteral nutrition following intensive cytotoxic therapy: an exploratory study on the need for parenteral nutrition after various treatment approaches for haematological malignancies.

Patients receiving intensive cytotoxic therapy are traditionally supported with parenteral nutrition (PN), although it is unclear whether all patients benefit from PN. This study aimed to identify regimen-associated differences in PN requirements, to reveal discrepancies between the number of PN indications and the frequency with which PN was actually given, and to describe characteristics of patients who met nutritional goals without PN. PN indications were defined as: (1) severe malnutrition at admission; (2) a prolonged period (7-10 days) of minimal oral intake; or (3) clinical weight loss >10%. PN was found to be needed in only 35% of consolidation courses, compared with 80% during remission induction and 55% during BMT. Significant differences were also seen between BMT protocols: PN was required in only 37% of autologous BMT recipients conditioned without total body irradiation (for lymphoma) vs 92% of recipients of a mismatched graft. A high body mass index was the only significant characteristic of patients who could do without PN. In conclusion, PN is not required for all patients undergoing intensive cytotoxic therapy. Screening of nutritional status at the start of therapy and monitoring oral intake following cytotoxic treatment may allow more appropriate identification of patients requiring PN.

Adult↗

Phase III efficacy study of interleukin-3 after autologous bone marrow transplantation in patients with malignant lymphoma.

We evaluated the efficacy of recombinant human interleukin-3 (rhIL-3) in reducing the number of platelet transfusions and major infections after autologous bone marrow transplantation (ABMT) in patients with malignant lymphoma. 198 patients with non-Hodgkin's lymphoma (NHL, n = 111) and Hodgkin's disease (HD, n = 87) were randomized to receive rhIL-3 10 microgram/kg/d (n = 130) or placebo (n = 68) for a maximum of 28 d after ABMT. Several well-known conditioning regimens were used. From day 1 after ABMT patients were treated with placebo or rhIL-3 at a dose of 10 microgram/kg/d by continuous i.v. infusion for 7 d and then by s.c. administration for 21 d or until platelet (50 x 109/l) and neutrophil (0.5 x 109/l) recovery had occurred. Treatment was completed in 54% of the patients in the rhIL-3 group versus 75% in the placebo group (P < 0.004). Adverse events were the main reason for premature discontinuation in the IL-3 group (23% IL-3 v 5% placebo). The median number of platelet transfusions was not significantly different between the IL-3 group and the placebo group (8.0 IL-3 v 6.0 placebo, P = 0.09). Platelet engraftment (>/= 20 x 109/l) was not significantly faster in the IL-3 group (28 d in the IL-3 and 27 d in the placebo group, P = 0.06) and the incidence of haemorrhagic complications was similar in both groups. In patients receiving the full intended dose of rhIL-3, platelet engraftment to >/= 20 x 109/l was delayed (P = 0.007). The median time to neutrophil engraftment was 23 d in the IL-3 and 25 d for the placebo group (P = 0.39). There was no difference in the incidence of major infections. We conclude that treatment with IL-3 has no clinical benefit in patients receiving ABMT for malignant lymphoma.

Bone Marrow Transplantation↗

Mechanisms underlying hematopoietic stem cell mobilization induced by the CXC chemokine interleukin-8.

The CXC chemokine interleukin-8 induces rapid mobilization of hematopoietic progenitor cells in mice and monkeys. Antibodies against the beta 2-integrin leukocyte function-associated antigen-1 completely blocked interleukin-8-induced mobilization. This was not due to a direct effect on the hematopoietic progenitor cells, as leukocyte function-associated antigen-1 was found not to be expressed on hematopoietic progenitor cells. Additional experiments showed that interleukin-8 induces the rapid release of the metalloproteinase gelatinase B, concurrent with the mobilization of hematopoietic progenitor cells. Mobilization could be completely prevented by anti-gelatinase B antibodies. Because neutrophils express leukocyte function-associated antigen-1 and high affinity interleukin-8 receptors, and release gelatinase B upon stimulation with interleukin-8, we hypothesized that neutrophils are key mediators in interleukin-8-induced stem cell mobilization. Further studies showed that mobilization by interleukin-8 was completely absent in mice rendered neutropenic with anti-granulocytic antibodies. Taken together, these data are consistent with an essential role for neutrophils in interleukin-8-induced stem cell mobilization.

Animals↗

Vincristine, doxorubicin and dexamethasone (VAD) administered as rapid intravenous infusion for first-line treatment in untreated multiple myeloma.

We examined the feasibility of achieving a rapid response in patients with previously untreated multiple myeloma by administering vincristine 0.4 mg and doxorubicin 9 mg/m2 as a rapid intravenous infusion for 4 d together with intermittent high-dose dexamethasone 40 mg (VAD) for remission induction treatment in patients who were scheduled to receive high-dose therapy. 139 patients (86 male, 53 female; median age 53 years, range 32-65 years; Durie & Salmon stage IIA: 42, IIB: one, IIIA: 89, IIIB: seven) were included in a prospective multicentre study in which VAD was administered as remission induction treatment and was followed by intensified treatment. The response was evaluated according to the criteria of the Eastern Cooperative Oncology Group (ECOG). The results of treatment were evaluable in 134 patients. Five patients died before evaluation. 86 patients (62%) achieved a partial response (PR) and seven patients (5%) achieved a complete response (CR), which equates to a response rate of 67%. The main side-effect was mild neurotoxicity, which was observed in 18% of the patients. Fever or infections were reported in 27% of the patients. VAD administered as an outpatient regimen, based on rapid intravenous infusion, is an effective induction regimen for untreated myeloma with a 67% response rate and acceptable toxicity.

Adult↗

T cells recognizing leukemic CD34(+) progenitor cells mediate the antileukemic effect of donor lymphocyte infusions for relapsed chronic myeloid leukemia after allogeneic stem cell transplantation.

Adoptive immunotherapy with donor lymphocyte infusions (DLI) is an effective treatment for relapsed chronic myeloid leukemia (CML) after allogeneic stem cell transplantation. To identify the effector and target cell populations responsible for the elimination of the leukemic cells in vivo we developed an assay to measure the frequency of T lymphocyte precursor cells capable of suppressing leukemic progenitor cells. Target cells in this assay were CML cells that were cultured in the presence of stem cell factor, interleukin 3, granulocyte-macrophage colony-stimulating factor, granulocyte colony-stimulating factor, and erythropoietin. [3H]thymidine incorporation at day 7 represented the proliferation of the progeny of the CD34(+) CML progenitor cells, and not of the more mature CD34(-) CML cells. Effector cells were mononuclear cells, which were used in a limiting dilution analysis to measure the frequencies of CML progenitor cell-inhibitory lymphocyte precursors (PCILp) in peripheral blood of seven patients before and after DLI for relapsed CML. In the six patients who entered complete remission, a 5- to 100-fold increase of PCILp was found during the clinical response. In the patient with resistant relapse the frequency of PCILp was <10 per ml before and after DLI. Leukemia-reactive helper T lymphocyte precursor frequencies remained unchanged after DLI. A significant increase in cytotoxic T lymphocyte precursor frequency against more mature leukemic cells was found in only two responding patients. These results indicate that T cells specifically directed against CD34(+) CML progenitor cells mediate the antileukemic effect of DLI.

Antigens, CD34↗

Assessment of telomere length in hematopoietic interphase cells using in situ hybridization and digital fluorescence microscopy.

Telomeres are G/C-rich repetitive DNA sequences at the end of all eukaryotic chromosomes. The loss of telomeric repeat sequences during cell divisions has been proposed as a possible mechanism for cell senescence. The standard procedure for measurement of telomere length is Southern blot (SB) hybridization with a telomere-specific probe. However, in using this technique no information can be obtained on variation in telomeric fragments due to interchromosomal, intrachromosomal, and intercellular differences. Lansdorp et al. (Hum Mol Genet 5:685-691, 1996) developed a method to measure individual telomeres, using in situ hybridization on metaphase chromosomes, employing peptide nucleic acid (PNA) probes and digital fluorescence microscopy. In this paper we describe a method that can be used to assess telomeric length in interphase cells. An algorithm was developed to measure the total intranuclear fluorescence in situ hybridization (FISH) signal, which features accurate correction for the local autofluorescence. Application of this methodology to samples of fetal liver, umbilical cord blood, and adult bone marrow cells showed a gradual decrease of average telomeric length. Southern blot analysis and PNA FISH measurements on chromosomes in the same samples showed similar results. Advantages of interphase measurements include the possibility of studying nonproliferating cells, thus avoiding selection and cell culturing.

Adult↗

Anti-LFA-1 blocking antibodies prevent mobilization of hematopoietic progenitor cells induced by interleukin-8.

Previously, we have shown that interleukin (IL)-8 induces the rapid (15 to 30 minutes) mobilization of hematopoietic progenitor cells (HPC) in mice. Because integrins are essential for adhesion and transendothelial migration of HPC, we studied the involvement of the beta2-integrin leukocyte function-associated antigen-1 (LFA-1) in IL-8-induced mobilization. After a single injection of blocking anti-LFA-1 antibodies, no mobilization of colony-forming cells was observed. In addition, when mice were pretreated with anti-LFA-1 or saline and subsequently injected with 30 microg of IL-8, mobilization of HPC was completely blocked. We showed that this was not due to anti-LFA-1 antibodies affecting colony formation, as addition of anti-LFA-1 antibodies to colony cultures in semisolid medium had no inhibitory activity. Also, anti-intercellular adhesion molecule (ICAM)-1 antibodies, directed to the main ligand of LFA-1 significantly inhibited the IL-8-induced mobilization. Furthermore, IL-1-induced mobilization was significantly inhibited by anti-LFA-1 antibodies. Because LFA-1 is reported to be expressed on more differentiated HPC, it was considered that the IL-8-induced mobilization of more primitive HPC would not be blocked by anti-LFA-1 antibodies. Transplantation of blood-derived mononuclear cells (MNC) from IL-8-mobilized animals pretreated with anti-LFA-1 antibodies protected only 25% of lethally irradiated recipient mice, whereas the radioprotection rate of control mice transplanted with MNC derived from IL-8-mobilized animals was 86% (P < .01). Anti-LFA-1 antibodies did not interfere with stem cell homing, as transplantation of IL-8-mobilized blood MNC, incubated in vitro with these antibodies resulted in 100% radioprotection. We conclude that anti-LFA-1 antibodies completely prevent the rapid mobilization of colony-forming cells and of cells with radioprotective capacity induced by IL-8. These results indicate a major role for the beta2-integrin LFA-1 in the IL-8-induced mobilization of hematopoietic stem cells.

Animals↗