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ABSTRACT: To determine the influence of microbial air quality during Hickman catheter insertion in the operating theater versus insertion in the radiology suite on the incidence of catheter-related infections (CRIs).
Hemato-oncologic patients with prolonged neutropenia on antimicrobial prophylaxis were entered onto the study. Catheters were inserted by experienced radiologists under sonographic and fluoroscopic guidance.
Forty-eight Hickman catheters in 39 patients were inserted (23 in the operating theater, 25 in the radiology suite). CRIs were seen in 16 catheters (33%; six per 1,000 catheter days; eight in each group). Local infections were found in nine catheters (22%; six in the operating theater v three in the radiology suite; not significant [NS]), catheter-related bacteremia was found in 10 (29%; three in the operating theater v seven in the radiology suite; NS). Coagulase-negative staphylococci (CoNS) caused all CRIs. Despite early vancomycin therapy, 11 (69%; four in the operating room group v seven in the radiology suite group; NS) of the catheters with CRIs had to be removed prematurely. At 90 days after insertion, catheter survival was 78% and 60% (NS) for the operating room and radiology suite, respectively. Multivariate analysis showed that neutropenia increased the CRI risk 20-fold (P =.004) and was strongly related to premature catheter removal owing to infection (relative risk = 11.9; P =.009). Neutropenia on the day of insertion was also significantly correlated with CRI (P =.04) and premature catheter removal owing to infection (P =.03). Serial cultures of blood, exit site, and catheter hub did not predict the development of CRI.
The high incidence of Hickman CRI caused by CoNS was not associated with insertion location (operating theater v radiology suite). Neutropenia, including neutropenia on the day of insertion, was a significant risk factor for CRI and infection-related catheter removal.
Journal of Clinical Oncology 05/1999; 17(4):1304. · 18.37 Impact Factor
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H Rozemuller,
W Terpstra,
E J Rombouts,
M Lawler,
C Byrne,
D J FitzGerald,
R J Kreitman, J J Wielenga,
B Löwenberg,
I P Touw,
A Hagenbeek,
A C Martens
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ABSTRACT: The severe combined immunodeficient (SCID) mouse model may be used to evaluate new approaches for the treatment of acute myeloid leukemia (AML). We have previously demonstrated the killing of SCID mouse leukemia initiating cells by in vitro incubation with human GM-CSF fused to Diphtheria toxin (DT-huGM-CSF). In this report, we show that in vivo treatment with DT-huGM-CSF eliminates AML growth in SCID mice. Seven cases of AML were studied. SCID mice were treated intraperitoneally with the maximally tolerated dose of 75 microg/kg/day for 7 days. Antileukemic efficacy was determined at days 40 and 80 after transplantation, by enumerating the percentages of human cells in SCID bone marrow using flow cytometry and short tandem repeat polymerase chain reaction (STR-PCR) analysis. Four out of seven AML cases were sensitive to in vivo treatment with DT-huGM-CSF at both evaluation time points. In three of these cases, elimination of human cells was demonstrated by flow cytometry and STR-PCR. One AML case showed moderate sensitivity for DT-huGM-CSF, and growth of the two remaining AML cases was not influenced by DT-huGM-CSF. Sensitivity was correlated with GM-CSFR expression. Our data show that DT-huGM-CSF can be used in vivo to reduce growth of AML and warrant further development of DT-huGM-CSF for the treatment of human AML.
Leukemia 01/1999; 12(12):1962-70. · 9.56 Impact Factor
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ABSTRACT: The detailed analysis of 411 strains of coagulase-negative staphylococci (CoNS) obtained from 40 neutropenic hemato-oncologic patients (61 Hickman catheter episodes) on intensive chemotherapy is described. By random amplification of polymorphic DNA (RAPD) analysis, a total of 88 different genotypes were detected: 51 in air samples and 30 in skin cultures prior to insertion, 12 in blood cultures after insertion, and only 5 involved in catheter-related infections (CRI). Two RAPD genotypes of Staphylococcus epidermidis predominated, and their prevalence increased during patient hospitalization. At insertion, these clones constituted 11 of 86 (13%) CoNS isolated from air samples and 33 of 75 (44%) CoNS isolated from skin cultures. After insertion, their combined prevalence increased to 33 of 62 (53%) in catheters not associated with CRI and 139 of 188 (74%) in catheters associated with CRI (P = 0.0041). These two predominant S. epidermidis clones gave rise to a very high incidence of CRI (6.0 per 1,000 catheter days) and a very high catheter removal rate for CRI, 70%, despite prompt treatment with vancomycin. A likely source of S. epidermidis strains involved in CRI appeared to be the skin flora in 75% of cases. The validity of these observations was confirmed by pulsed-field gel electrophoresis (PFGE) of SmaI DNA macrorestriction fragments of blood culture CoNS isolates. Again, two predominant CoNS genotypes were found (combined prevalence, 60%). RAPD and PFGE yielded concordant results in 75% of cases. Retrospectively, the same two predominant CoNS clones were also found among blood culture CoNS isolates from the same hematology department in the period 1991 to 1993 (combined prevalence, 42%) but not in the period 1978 to 1982. These observations underscore the pathogenic potential of clonal CoNS types that have successfully and persistently colonized patients in this hemato-oncology department.
Journal of Clinical Microbiology 10/1998; 36(9):2696-702. · 4.15 Impact Factor
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ABSTRACT: In vivo expansion and multilineage outgrowth of human immature hematopoietic cell subsets from umbilical cord blood (UCB) were studied by transplantation into hereditary immunodeficient (SCID) mice. The mice were preconditioned with Cl2MDP-liposomes to deplete macrophages and 3.5 Gy total body irradiation (TBI). As measured by immunophenotyping, this procedure resulted in high levels of human CD45(+) cells in SCID mouse bone marrow (BM) 5 weeks after transplantation, similar to the levels of human cells observed in NOD/SCID mice preconditioned with TBI. Grafts containing approximately 10(7) unfractionated cells, approximately 10(5) purified CD34+ cells, or 5 x 10(3) purified CD34+CD38- cells yielded equivalent numbers of human CD45+ cells in the SCID mouse BM, which contained human CD34+ cells, monocytes, granulocytes, erythroid cells, and B lymphocytes at different stages of maturation. Low numbers of human GpA+ erythroid cells and CD41+ platelets were observed in the peripheral blood of engrafted mice. CD34+CD38+ cells (5 x 10(4)/mouse) failed to engraft, whereas CD34- cells (10(7)/mouse) displayed only low levels of chimerism, mainly due to mature T lymphocytes. Transplantation of graded numbers of UCB cells resulted in a proportional increase of the percentages of CD45+ and CD34+ cells produced in SCID mouse BM. In contrast, the number of immature, CD34+CD38- cells produced in vivo showed a second-order relation to CD34+ graft size, and mice engrafted with purified CD34+CD38- grafts produced 10-fold fewer CD34+ cells without detectable CD34+CD38- cells than mice transplanted with equivalent numbers of unfractionated or purified CD34+ cells. These results indicate that SCID repopulating CD34+CD38- cells require CD34+CD38+ accessory cell support for survival and expansion of immature cells, but not for production of mature multilineage progeny in SCID mouse BM. These accessory cells are present in the purified, nonrepopulating CD34+CD38+ subset as was directly proven by the ability of this fraction to restore the maintenance and expansion of immature CD34+CD38- cells in vivo when cotransplanted with purified CD34+CD38- grafts. The possibility to distinguish between maintenance and outgrowth of immature repopulating cells in SCID mice will facilitate further studies on the regulatory functions of accessory cells, growth factors, and other stimuli. Such information will be essential to design efficient stem cell expansion procedures for clinical use.
Blood 04/1998; 91(6):1966-76. · 9.90 Impact Factor
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B Löwenberg,
M A Boogaerts,
S M Daenen,
G E Verhoef,
A Hagenbeek,
E Vellenga,
G J Ossenkoppele,
P C Huijgens,
L F Verdonck,
J van der Lelie, J J Wielenga,
H C Schouten,
J Gmür,
A Gratwohl,
U Hess,
M F Fey,
W L van Putten
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ABSTRACT: The hematopoietic growth factors (HGFs) introduced into induction chemotherapy (CT) of acute myeloid leukemia (AML) might be of benefit to treatment outcome by at least two mechanisms. HGFs given on days simultaneously with CT might sensitize the leukemic cells and enhance their susceptibility to CT. HGFs applied after CT might hasten hematopoietic recovery and reduce morbidity or mortality.
We set out to evaluate the use of granulocyte-macrophage colony-stimulating factor (GM-CSF; 5 microg/kg) in a prospective randomized study of factorial design (yes or no GM-CSF during CT, and yes or no GM-CSF after CT) in patients aged 15 to 60 years (mean, 42) with newly diagnosed AML. GM-CSF was applied as follows: during CT only (+/-, n = 64 assessable patients), GM-CSF during and following CT (+/+, n = 66), no GM-CSF (-/-, n = 63), or GM-CSF after CT only (-/+, n = 60).
The complete response (CR) rate was 77%. At a median follow-up time of 42 months, probabilities of overall survival (OS) and disease-free survival (DFS) at 3 years were 38% and 37% in all patients. CR rates, OS, and DFS did not differ between the treatment groups (intention-to-treat analysis). Neutrophil recovery (1.0 x 10(9)/L) and monocyte recovery were significantly faster in patients who received GM-CSF after CT (26 days v 30 days; neutrophils, P < .001; monocytes, P < .005). Platelet regeneration, transfusion requirements, use of antibiotics, frequency of infections, and duration of hospitalization did not vary as a function of any of the therapeutic GM-CSF modalities. More frequent side effects (eg, fever and fluid retention) were noted in GM-CSF-treated patients predominantly related to the use of GM-CSF during CT.
Priming of AML cells to the cytotoxic effects of CT by the use of GM-CSF during CT or accelerating myeloid recovery by the use of GM-CSF after CT does not significantly improve treatment outcome of young and middle-aged adults with newly diagnosed AML.
Journal of Clinical Oncology 01/1998; 15(12):3496-506. · 18.37 Impact Factor
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W Terpstra,
H Rozemuller,
D A Breems,
E J Rombouts,
A Prins,
D J FitzGerald,
R J Kreitman, J J Wielenga,
R E Ploemacher,
B Löwenberg,
A Hagenbeek,
A C Martens
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ABSTRACT: We studied the cell kill induced by granulocyte-macrophage colony-stimulating factor (GM-CSF ) fused to Diphtheria Toxin (DT-GM-CSF ) in acute myeloid leukemia (AML) samples and in populations of normal primitive hemopoietic progenitor cells. AML samples from three patients were incubated in vitro with 100 ng/mL DT-GM-CSF for 48 hours, and AML cell kill was determined in a proliferation assay, a clonogenic assay colony-forming unit-AML (CFU-AML) and a quantitative long-term bone marrow (BM) culture ie, the leukemic-cobblestone area forming cell assay (L-CAFC). To measure an effect on cells with in vivo leukemia initiating potential DT-GM-CSF exposed AML cells were transplanted into immunodeficient mice. In two out of three samples it was shown that all AML subsets, including those with long-term abilities in vivo (severe combined immunodeficient mice) and in vitro (L-CAFC assay) were reduced in number by DT-GM-CSF. Cell kill induced by DT-GM-CSF could be prevented by coincubation with an excess of GM-CSF, demonstrating that sensitivity to DT-GM-CSF is specifically mediated by the GM-CSF receptor. Therefore, binding and internalization of GM-CSF probably occur in immature AML precursors of these two cases of AML. The third AML sample was not responsive to either GM-CSF or DT-GM-CSF. The number of committed progenitors of normal bone marrow (burst-forming unit-erythroid, colony-forming unit granulocyte- macrophage, and cobble stone area forming cell [CAFC] week 2) and also the number of cells with long-term repopulating ability, assayed as week 6 CAFC, were unchanged after exposure to DT-GM-CSF (100 ng/mL, 48 hours). These studies show that DT-GM-CSF may be used to eliminate myeloid leukemic cells with long-term potential in vitro and in immunodeficient mice, whereas normal hemopoietic stem cells are spared.
Blood 12/1997; 90(9):3735-42. · 9.90 Impact Factor
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W Terpstra,
P J Leenen,
C van den Bos,
A Prins,
W A Loenen,
M M Verstegen,
S van Wyngaardt,
N van Rooijen,
A W Wognum,
G Wagemaker, J J Wielenga,
B Löwenberg
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ABSTRACT: Transplantation of normal and malignant human hematopoietic cells into severe combined immunodeficient (SCID) mice allows for evaluation of long-term growth abilities of these cells and provides a preclinical model for therapeutic interventions. However, large numbers of cells are required for successful engraftment in preirradiated mice due to residual graft resistance, that may be mediated by cells from the mononuclear phagocytic system. Intravenous (i.v.) injection of liposomes containing dichloromethylene diphosphonate (Cl2MDP) may eliminate mouse macrophages in spleen and liver. In this study outgrowth of acute myeloid leukemia (AML) cells and umbilical cord blood (UCB) cells in SCID mice conditioned with a single i.v. injection of Cl2MDP liposomes in addition to sublethal total body irradiation (TBI) was compared to outgrowth of these cells in SCID mice that had received TBI alone. A two- to 10-fold increase in outgrowth of AML cells was observed in four cases of AML. Administration of 10(7) UCB cells reproducibly engrafted SCID mice that had been conditioned with Cl2MDP liposomes and TBI, whereas human cells were not detected in mice conditioned with TBI alone. As few as 2 x 10(4) purified CD34+ UCB cells engrafted in all mice treated with Cl2MDP liposomes. In SCID mice treated with macrophage depletion unexpected graft failures were not observed. Histological examination of the spleen showed that TBI and Cl2MDP liposomes i.v. resulted in a transient elimination of all macrophage subsets in the spleen, whereas TBI had a minor effect. Cl2MDP liposomes were easy to use and their application was not associated with appreciable side-effects. Cl2MDP liposome pretreatment in combination with TBI allows for reproducible outgrowth of high numbers of human hematopoietic cells in SCID mice.
Leukemia 08/1997; 11(7):1049-54. · 9.56 Impact Factor
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ABSTRACT: A subset of leukemic cells is assumed to maintain long-term growth of acute myeloid leukemia (AML) in vivo. Characterization of these AML progenitor cells may further define growth properties of human leukemia. In vitro incubations with 5-fluorouracil (5-FU) have been used for enrichment of normal primitive hematopoietic stem cells. By analogy to normal hematopoiesis, it was hypothesized that primitive leukemic stem cells might be kinetically more inactive than colony-forming cells (colony-forming units-AML [CFU-AML]). To examine this hypothesis, conditions were established for incubation with 5-FU that eliminated all CFU-AML. These conditions selected a 5-FU-resistant AML fraction that was evaluated for its capacity for long-term growth by transplantation into mice with severe combined immunodeficiency (SCID) and long-term culture in the quantitative cobblestone area-forming cell (CAFC) assay. Transplantation of the 5-FU-resistant fraction of four cases of AML into SCID mice resulted in growth of AML. Whereas no CFU-AML survived, 31% to 82% of primitive (week-6) CAFC were recovered from the 5-FU-treated cells. Hematopoietic cells proliferating in the CAFC assay were shown to be leukemic by cytologic, cytogenetic, or molecular analysis. The reduction of AML growth as determined by outgrowth of AML in SCID mice was in the same order of magnitude as the primitive (week-6) CAFC reduction. This indicates that both assays measure closely related cell populations and that the CAFC assay can be used to study long-term growth of AML. These results show a hierarchy of AML cells that includes 5-FU-resistant progenitors. These cells are characterized as primitive (week-6) CAFC and as leukemia-initiating cells in SCID mice.
Blood 10/1996; 88(6):1944-50. · 9.90 Impact Factor
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ABSTRACT: Acute myeloid leukemia (AML) proliferation in vivo is maintained by a small fraction of progenitor cells. These cells have been assumed to express an immature phenotype and to produce most colony-forming units (CFU-AML). For one case of AML (French-American-British [FAB] M1, normal cytogenetics), we examined the capacity of the CD34+ (25% of unseparated AML cells) and CD34- fractions to initiate leukemia in severe combined immunodeficient (SCID) mice. In addition, the production of CFU-AML and nucleated cells (NC) of these subsets was investigated in long-term bone marrow culture (LTBMC). The frequencies of cobblestone area-forming cells (CAFC) were also estimated; early appearing cobblestone areas (CAs) are indicative of relatively mature progenitors and late CAs represent the progeny of primitive progenitors. In mice transplanted with CD34- (98% pure) or CD34+ (98% pure) grafts, similar AML cell growth was seen throughout an observation period of 106 days. The capacity to establish long-term growth from the CD34- cells was confirmed by renewed outgrowth after retransplantation. In vitro, the CD34- fraction contained both immature and mature CAFCs and produced high numbers of CFU-AML and NC in LTBMC. The CD34+ fraction produced only small numbers of CFU-AML, NC, and mature CAFCs. Therefore, the expression of CD34 and the content of CFU-AML were not associated with long-term growth of AML. However, similar frequencies of primitive CAFCs were observed in both fractions. Thus, both CD34- and CD34+ subsets of this AML sample contained immature progenitors with the capacity to initiate long-term AML growth as characterized in vivo (in SCID mice) as well as in vitro (in CAFC assay), indicating asynchrony between functional and immunophenotypical maturation of AML progenitor cell compartments.
Blood 04/1996; 87(6):2187-94. · 9.90 Impact Factor
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ABSTRACT: Patients with AML who relapse after an initial remission, have a poor prognosis. Administration of hemopoietic growth factors (HGFs) such as interleukin-3 (IL-3) during chemotherapy may result in an increased cell kill by cytotoxic agents. In addition, administration of IL-3 following chemotherapy may potentially accelerate hemopoietic recovery from chemotherapy-induced bone marrow hypoplasia. We performed an open labelled, phase I/II study in which patients received IL-3 by continuous infusion from 24 h before the beginning of chemotherapy until day 28. Chemotherapy included daunorubicin or mitoxantrone days 1-3 and cytarabine 200 mg/m2 days 1-7. IL-3 was given at a dose of 5 microgram(s)/kg/day in 10 patients, 7.5 microgram(s)/kg /day in six patients and 10 microgram(s)/kg/day in four patients. Complete remissions (CR) after one cycle of this treatment were obtained in 5/10 patients and 5 microgram(s)/ kg group, 2/6 in the 7.5 microgram(s)/kg group and 3/4 in the 10 microgram(s)/kg group). Thus, 50% (10/20) of all individuals and 45% (5/11) of the elderly patients attained CR. Eight of 20 patients entered PR, and 2/20 patients died during the hypoplastic phase from infectious complications. Neutrophils and platelets recovered to 0.5 x 10(9)/l at day 25 (median) and to 50 x 10(9)/l at day 32, respectively. Adverse events during IL-3 and concomitant chemotherapy were fluid retention (4/20), rash (14/20), bone pain (2/20), headache (10/20), chest pain (1/20), arthritis (1/20), fever and nausea. IL-3 (at the dose of 10 microgram(s)/kg) was discontinued in two patients because of side-effects (fluid retention, fever, rash and chest pain), and in two other patients the high IL-3 dose was tolerated with no problems for 29 days. Thus, IL-3 applied to patients with high-risk AML at dosages of 5-10 microgram(s)/kg is tolerated with acceptable toxicity and results in a satisfactory frequency of complete responses following a single treatment cycle.
Leukemia 02/1996; 10(1):43-7. · 9.56 Impact Factor
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ABSTRACT: Patients with acquired von Willebrand disease may present with severe bleeding, which is usually difficult to manage. Adequate haemostasis in acquired von Willebrand disease may be achieved with the infusion of factor VIII/von Willebrand factor concentrates or with the administration of desmopressin. We report a case of acquired von Willebrand disease with severe postoperative bleeding, responding poorly to classical von Willebrand factor replacement therapy but successfully treated with high-dose intravenous gammaglobulins. This new treatment mode of acquired von Willebrand disease is discussed in the light of a critical analysis of the literature.
Postgraduate Medical Journal 01/1995; 70(830):916-20. · 1.94 Impact Factor
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ABSTRACT: Acute myeloid leukemic (AML) cells not only express receptors for various cytokines but also produce hemopoietic growth factors themselves. Thus, they are able to stimulate their own activation and proliferation, a phenomenon known as autocrine growth. The cell cycle kinetics of AML blast cells are susceptible to stimulation by a variety of cytokines, including granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin (IL)-3, granulocyte colony stimulating factor and stem cell factor. GM-CSF and IL-3 can markedly enhance the cytotoxicity of chemotherapeutic agents by increasing the proportion of AML cells in S-phase at any given time and by altering the metabolic status of the AML cells. A number of clinical studies involving the use of GM-CSF in association with chemotherapy in patients with AML are currently ongoing. In the next few years the first clinical results will become available indicating whether the use of cytokines holds any benefit for patients with AML.
Anti-Cancer Drugs 06/1993; 4 Suppl 1:17-20. · 2.41 Impact Factor
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ABSTRACT: Recombinant rhesus monkey interleukin-3 (IL-3) was administered to normal rhesus monkeys in graded doses ranging from 3 to 30 micrograms/kg/d subcutaneously for 30 consecutive days or given as a continuous intravenous infusion at a dose of 30 micrograms/kg/d for 16 days. After a lag phase of about 1 week, a highly increased, dose-dependent production of bone marrow-derived blood cells was observed, preceded by amplification of bone marrow hematopoietic progenitor cells. Simultaneously, peripheral blood progenitor cells rose. The increase included basophilic, eosinophilic and neutrophilic granulocytes, monocytes, and the erythrocyte and platelet lineages. Characteristically, a T-lymphocyte response was absent. It is concluded that IL-3 in vivo stimulates blood cell production from an immature, multipotent progenitor cell.
Blood 01/1991; 76(11):2235-41. · 9.90 Impact Factor
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ABSTRACT: A phase II study was conducted to evaluate the efficacy and toxicity of lomustine, cytarabine, mitoxantrone and prednisone (CAMP) chemotherapy in doxorubicin-resistant intermediate- and high-grade malignant non-Hodgkin's lymphomas (NHL). Among 30 patients, the complete remission rate was 27% (duration: 10, 16, 22, 35, 35+, 42+, 51+, 55+ months) and the partial remission rate was 20%. Median survival for complete responders was more than 4 years. The best responses were seen in patients with relapsed NHL compared to those with primary refractory NHL. Toxicity was mainly related to myelosuppression. The results suggest that the CAMP schedule can be applied on an outpatient basis with satisfactory efficacy in patients with relapsing intermediate- and high-grade malignant NHL.
Seminars in Oncology 01/1991; 17(6 Suppl 10):24-7. · 3.50 Impact Factor
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ABSTRACT: Interleukin-3 (IL-3) is a hemopoietic growth factor involved in the survival, proliferation and differentiation of multipotent hemopoietic cells. In five mammalian species, including man, the gene encoding IL-3 has been isolated and expressed to yield the mature recombinant proteins. The human IL-3 gene encodes a protein of 133 amino acids with two conserved cysteine residues and 2 potential N-linked glycosylation sites; human native IL-3 has not been characterized. Comparison of the IL-3 genes revealed a more rapid evolutionary divergence than has been observed for other hemopoietic growth factors, and, hence, a more pronounced species specificity of the functional proteins was found. In agreement with its stimulatory action on immature multipotent cells, the in vivo actions of homologous recombinant IL-3 in nonhuman primates include a highly increased production of blood cells along the neutrophilic, eosinophilic and basophilic granulocyte as well as the monocyte, red cell and platelet lineages.
Biotherapy 02/1990; 2(4):337-45.
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ABSTRACT: Reconstitution of levels of pheripheral blood cells following bone marrow transplantation is dependent on the engraftment of the pluripotent hemopoietic stem cells of the transplant. In the case of allogeneic transplants, a successful engraftment carries a high risk of the development of GvHD, which is a serious and often life-threatening complication. T cell depletion of the allogeneic bone marrow graft can completely prevent GvHD provided a sufficient degree of depletion is achieved. Experiments with laboratory animals and clinical experience have shown that the higher rate of graft failure that occurs with T cell depleted marrow grafts can be avoided by increasing the conditioning dose of TBI with approximately 2 Gy. Experiments with T cell depleted autologous bone marrow grafts and with grafts of autologous purified stem cells in monkeys demonstrate that the decreased engraftment of T cell depleted bone marrow cannot be ascribed to a trophic function of T lymphocytes, e.g. via production of hemopoietic growth factors. Using sublethally irradiated Rhesus monkeys, the effect of post-irradiation treatment with GM-CSF or with Rhesus monkey r IL-3 was studied. Enhancement of blood cell regeneration was only recorded within a relatively small TBI dose range. When the dose of TBI induces more than approximately a 3-log stem cell kill, treatment with growth factors becomes ineffective. Comparable results are obtained when supralethally irradiated monkeys given relatively small grafts of T cell depleted autologous bone marrow were treated with the hemopoietic growth factors.
Progress in clinical and biological research 02/1990; 352:479-91.
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The Netherlands Journal of Medicine 09/1988; 33(1-2):26-9. · 2.07 Impact Factor
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ABSTRACT: Complement-mediated lysis of (subsets of) T lymphocytes in bone marrow grafts is increasingly used to prevent acute graft-versus-host disease in human bone marrow transplant recipients, especially in case of major immunogenetic disparity between donor and recipient. Since T lymphocyte depletion has resulted in an increased frequency of allogeneic engraftment failures, its effect on hemopoietic reconstitution was measured in rhesus monkeys. The reactivity patterns of commonly used types of antihuman T lymphocyte monoclonal antibodies (MCAs) with rhesus monkey lymphocytes was analyzed using a double-label cytofluorometry technique and found to be very similar to those with human lymphocytes. The antibodies investigated included CAMPATH-1 (recognizing an antigen present on virtually all lymphocytes and monocytes), OKT4 + 4a (CD4, helper/inducer T lymphocytes), B9 (CD8, suppressor/cytotoxic T lymphocytes), WT-1 (CD7, pan-T), and anti-DR MCAs as stem cell toxic controls. Their possible toxicity to hemopoietic stem cells was studied by using a semiquantitative autologous regeneration assay. Cytotoxic lysis of cells in the bone marrow grafts reacting with the T lymphocyte purging MCAs did not result in delayed regeneration compared to untreated autologous grafts. It is concluded that T lymphocyte depletion using anti-T-lymphocyte MCAs does not influence the repopulating capacity of an autologous bone marrow graft.
Transplantation 03/1988; 45(2):301-7. · 4.00 Impact Factor
