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D C Dale

Publications and source records attributed to D C Dale.

At least 37 records · Page 2Linked to original sources
PubMed2000

Use of G-CSF for granulocyte transfusion therapy.

Patients with neutropenia, especially neutropenia following aggressive myeloablative therapy, are at high risk for developing infectious complications caused by bacteria and opportunistic fungi. Infections remain one of the leading causes of treatment failure in patients with cancer. Thus, new and innovative therapeutic strategies are needed for management of neutropenic patients with infection. Because neutrophils represent the first line of host defense, granulocyte transfusion therapy should be a logical therapeutic approach. Although such therapy has been employed sporadically for several decades, clinical benefit has been compromised by technical problems and low granulocyte yields resulting from inadequate donor stimulation. The discovery of granulocyte colony-stimulating factor (G-CSF) as a means to elevate blood neutrophil counts when administered to normal donors has rekindled interest in granulocyte transfusion therapy. Extensive experience has been gained worldwide with G-CSF in clinical practice, and adverse events have been minimal when G-CSF has been administered to patients or healthy persons in human trials. This review focuses on the use of G-CSF in granulocyte transfusion therapy, including technical considerations of granulocyte leukapheresis and storage, donor selection and stimulation, as well as treatment results and associated risks.

Blood Donors↗
PubMed2000

Inhibition of in vivo neutrophil transmigration by a novel humanized anti-CD11/CD18 monoclonal antibody.

Leukocyte adhesion receptors, including the beta-integrin (CD11/CD18) family, play an important role in inflammation via their regulatory effects on leukocyte adhesion, transmigration, and function. A randomized, placebo-controlled, double-blind study was conducted in healthy volunteers to evaluate the in vivo effects of a humanized anti-CD11/CD18 monoclonal antibody, Hu23F2G, on leukocyte activation and transmigration. Neutrophil migration to a site of cutaneous inflammation in vivo, as measured by the skin chamber technique, was significantly reduced in subjects 24 hours after Hu23F2G administration. At 96 hours, neutrophil migration was not significantly different in subjects who received Hu23F2G or placebo. In contrast, delayed-type hypersensitivity (DTH) testing, which involves activation and migration of T lymphocytes and macrophages, was unaffected by the Hu23F2G treatment. These responses to Hu23F2G in vivo are similar to the clinical phenotype of leukocyte adhesion deficiency (LAD) type 1, a congenital disorder of CD18 deficiency. The in vivo properties of Hu23F2G suggest therapeutic potential for use in the treatment of acute non-infectious inflammatory disorders mediated predominantly by neutrophils.

Adult↗
PubMed2000

Return of granulocyte transfusions.

Recently, several groups have begun to administer granulocyte colony-stimulating factor (G-CSF), a hematopoietic growth factor, with or without dexamethasone to mobilize peripheral blood neutrophils. Granulocyte colony-stimulating factor (600 microg subcutaneously) and dexamethasone (8 mg orally) given 12 hours before standard leukapheresis routinely results in the collection of approximately 80 x 10(9) granulocytes. This number of cells is sufficient to increase the neutrophil count of a severely neutropenic patient to normal and restore the recipients' ability to develop a neutrophil response in tissues. Several trials are ongoing to establish the clinical benefit of this new approach to supportive care for neutropenic patients.

Child↗
PubMed1999

Occurrence of periodic oscillations in the differential blood counts of congenital, idiopathic, and cyclical neutropenic patients before and during treatment with G-CSF.

Using techniques developed in astrophysics to deal with unequally sampled data sets, we have analyzed serial differential cell counts from 45 congenital, idiopathic, and cyclic neutropenic patients before and during treatment with recombinant human G-CSF (rhG-CSF). Our results show that the occurrence of significant cycling in the absolute neutrophil count (ANC) of neutropenics not classified as cyclical is much more prevalent than had been previously thought, and that not all the patients classified as cyclic show significant ANC periodicity. In these patients, cycling in more than one cell line may be involved. The range of periods encountered in these patients is much broader (between 11 and 52 days) than is usually associated with classical cyclical neutropenia, and there is no obvious connection between the range of periods and the patient's diagnostic category. Administration of rhG-CSF is able to induce significant cycling in neutropenic patients that were not cycling prior to treatment. In patients who had significant cycling before treatment, rhG-CSF may either decrease the period to between 11 and 14 days, or may obliterate any statistical evidence of cycling.

Adult↗
PubMed1999

Hematopoietic dynamics in grey collies.

Using Lomb periodogram analysis we have quantified variations in the peripheral neutrophil and platelet counts of the cyclical neutropenia animal model-the grey collie. We found that the amplitudes of the oscillations in these two cell lineages vary concomitantly. Further, the power spectrum and the shape of the oscillations in the absolute neutrophil counts vary together with the amplitude of the oscillations. As the amplitude of the oscillations increases, the height of the second subharmonic increases, giving rise to a distorted oscillation with two peaks per cycle. The particular dynamics of the absolute neutrophil counts can be reproduced by a combination of a delayed peripheral feedback, representing the peripheral control of granulopoiesis through granulocyte colony stimulating factor, together with a sinusoidal input representing an oscillatory input from the pluripotential stem cells to the granulocytic lineage. The same pluripotential stem cell input is probably responsible for the sinusoidal oscillations observed in the other cell lineages.

Animals↗
PubMed1999

Mutations in ELA2, encoding neutrophil elastase, define a 21-day biological clock in cyclic haematopoiesis.

Human cyclic haematopoiesis (cyclic neutropenia, MIM 162800) is an autosomal dominant disease in which blood-cell production from the bone marrow oscillates with 21-day periodicity. Circulating neutrophils vary between almost normal numbers and zero. During intervals of neutropenia, affected individuals are at risk for opportunistic infection. Monocytes, platelets, lymphocytes and reticulocytes also cycle with the same frequency. Here we use a genome-wide screen and positional cloning to map the locus to chromosome 19p13.3. We identified 7 different single-base substitutions in the gene (ELA2) encoding neutrophil elastase (EC 3. 4.21.37, also known as leukocyte elastase, elastase 2 and medullasin), a serine protease of neutrophil and monocyte granules, on unique haplotypes in 13 of 13 families as well as a new mutation in a sporadic case. Neutrophil elastase (a 240-aa mature protein predominantly found in neutrophil granules) is the target for protease inhibition by alpha1-antitrypsin, and its unopposed release destroys tissue at sites of inflammation. We hypothesize that a perturbed interaction between neutrophil elastase and serpins or other substrates may regulate mechanisms governing the clock-like timing of haematopoiesis.

Base Sequence↗
PubMed1999

Comparison of interferon-gamma, granulocyte colony-stimulating factor, and granulocyte-macrophage colony-stimulating factor for priming leukocyte-mediated hyphal damage of opportunistic fungal pathogens.

Proinflammatory cytokines have been proposed as adjunctive therapeutic agents to enhance the host immune response during infections caused by opportunistic fungi. The study compared the differential in vitro priming effects of interferon-gamma (IFN-gamma), granulocyte colony-stimulating factor (G-CSF), and granulocyte-macrophage colony-stimulating factor (GM-CSF) on hyphal damage of opportunistic fungi mediated by isolated neutrophils (polymorphonuclear leukocytes, PMNL) and buffy coat cells (polymorphonuclear leukocytes/peripheral blood mononuclear cells, PMNL/PBMC) from healthy donors. IFN-gamma (1000 U/mL) effectively primed both PMNL and PMNL/PBMC for enhanced hyphal damage of Aspergillus fumigatus, Fusarium solani, and Candida albicans. G-CSF (100 ng/mL) increased hyphal damage mediated by both PMNL and PMNL/PBMC against F. solani, and GM-CSF (100 ng/mL) augmented the antifungal activity of PMNL/PBMC against hyphal forms of both F. solani and C. albicans. IFN-gamma may be superior to G-CSF or GM-CSF for enhancing the microbicidal activity of PMNL and PMNL/PBMC against opportunistic fungi.

Fungi↗
PubMed1999

Modulation of neutrophil-mediated activity against the pseudohyphal form of Candida albicans by granulocyte colony-stimulating factor (G-CSF) administered in vivo.

Renewed interest in neutrophil transfusions has emerged with the development and clinical use of granulocyte colony-stimulating factor (G-CSF). G-CSF not only increases neutrophil (polymorphonuclear leukocyte, PMNL) production but also modulates various physiological properties of PMNL. The effects of G-CSF on PMNL-mediated fungicidal activity were evaluated by administration of G-CSF (300 micrograms/day subcutaneously) to 5 healthy volunteers for 6 days. G-CSF significantly enhanced PMNL-mediated damage of Candida albicans pseudohyphae by 33% (P=.007) on day 2 and by 44% (P=.04) on day 6 at a 10:1 effector:target ratio. In contrast, the ability of PMNL to induce damage of hyphae from either Fusarium solani or Aspergillus fumigatus did not significantly change during the study period. These data demonstrate that G-CSF administered in vivo modulates PMNL-mediated fungicidal activity against the pseudohyphal form of C. albicans, thereby suggesting potential utility of G-CSF as a biologic response-modifying therapy in some opportunistic fungal infections.

Adult↗
PubMed1999

Granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor: comparisons and potential for use in the treatment of infections in nonneutropenic patients.

Granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) enhance the antimicrobial functions of mature neutrophils. G-CSF differs from GM-CSF in its specificity of action on developing and mature neutrophils, its effects on neutrophil kinetics, and its toxicity profile. The toxicity profile of recombinant (r) GM-CSF is consistent with priming of macrophages for increased formation and release of inflammatory cytokines, whereas rG-CSF induces production of antiinflammatory factors, such as interleukin-1 receptor antagonist and soluble tumor necrosis factor receptors, and is protective against endotoxin- and sepsis-induced organ injury. The low toxicity of rG-CSF, results of animal models of infection, and extensive experience with neutropenic subjects have promoted clinical studies in nonneutropenic subjects, which indicate that rG-CSF may be beneficial as adjunctive therapy for treatment of serious bacterial and opportunistic fungal infections in nonneutropenic patients, including those with alterations in neutrophil function.

Animals↗
PubMed1998

Cyclical neutropenia and other periodic hematological disorders: a review of mechanisms and mathematical models.

Although all blood cells are derived from hematopoietic stem cells, the regulation of this production system is only partially understood. Negative feedback control mediated by erythropoietin and thrombopoietin regulates erythrocyte and platelet production, respectively, but the regulation of leukocyte levels is less well understood. The local regulatory mechanisms within the hematopoietic stem cells are also not well characterized at this point. Because of their dynamic character, cyclical neutropenia and other periodic hematological disorders offer a rare opportunity to more fully understand the nature of these regulatory processes. We review the salient clinical and laboratory features of cyclical neutropenia (and the less common disorders periodic chronic myelogenous leukemia, periodic auto-immune hemolytic anemia, polycythemia vera, aplastic anemia, and cyclical thrombocytopenia) and the insight into these diseases afforded by mathematical modeling. We argue that the available evidence indicates that the locus of the defect in most of these dynamic diseases is at the stem cell level (auto-immune hemolytic anemia and cyclical thrombocytopenia seem to be the exceptions). Abnormal responses to growth factors or accelerated cell loss through apoptosis may play an important role in the genesis of these disorders.

Anemia, Aplastic↗
PubMed1998

Effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on neutrophil kinetics and function in normal human volunteers.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) (250 microg/m2) was administered subcutaneously to 7 normal volunteers for up to 14 days to study its effects on neutrophil kinetics and function. With treatment, blood neutrophil counts rose gradually to peak at 3 1/2 times baseline by day 14. At day 5 marrow mitotic cells were increased and post-mitotic cells decreased, and the transit time through the post-mitotic marrow pool accelerated (normal = 6.4 days, GM-CSF = 3.9 days; P < 0.01). Treatment had little effect on the blood neutrophil half-life (normal = 9.6 +/- 1.3 hours; GM-CSF = 13.1 +/- 2.4 hours, P > 0.05); or the neutrophil turnover rate (normal = 78.5 +/- 11.9 x 10(7)/cells/kg/day, GM-CSF = 91.4 +/- 19.8 x 10(7)/cells/kg/day, P > 0.05). GM-CSF reduced the number of neutrophils migrating to skin chambers (normal = 104 +/- 25.0 x 10(6)/cells, GM-CSF = 48.6 +/- 16.0 x 10(6)/cells; P < 0.05). Treatment increased expression of CD11b/CD18 but not Fcgamma receptors (CD16, CD32, CD64). Treatment also stimulated the in vitro neutrophil respiratory burst in response to a variety of agonists, and this enhancement persisted for the duration of treatment. All subjects experienced local and systemic adverse effects and developed eosinophilia. This study indicates that GM-CSF at a dose of 250 microg/m2 causes neutrophilia chiefly by accelerating delivery of neutrophils from the marrow to the blood and by decreasing migration from the blood to the tissues, with only a modest effect on neutrophil production and blood half-life.

Adult↗
PubMed1998

Phase I study of a humanized anti-CD11/CD18 monoclonal antibody in multiple sclerosis.

OBJECTIVE: To evaluate the safety, pharmacokinetics, pharmacodynamics, and immunogenicity of a humanized anti-CD11/CD18 monoclonal antibody (Hu23F2G) in patients with multiple sclerosis. METHODS: In this phase I uncontrolled dose escalation study, patients (n = 24) with primary or secondary progressive multiple sclerosis received single intravenous infusions of Hu23F2G (0.01 to 4.0 mg/kg). Study parameters included safety, pharmacology, immunogenicity, and brain magnetic resonance imaging (MRI). RESULTS: Hu23F2G had few adverse effects, but 2 cases of urinary tract infection and 2 cases of gingivitis did occur. Transient leukocytes developed in some subjects receiving > or = 1.0 mg/kg. The pharmacokinetic response was nonlinear, with the area under the curve increasing out of proportion to the increase in dose. The mean terminal half-life increased with dose and was 21.9 (SD, 12.8) hours at the 4.0 mg/kg dose. High saturation (> 80%) of CD11/CD18 on circulating leukocytes was achieved with doses > or = 0.2 mg/kg. The duration of high leukocyte saturation was dose-dependent, persisting for more than a week at the 4.0 mg/kg dose. A marked decrease in leukocyte migration in response to cutaneous inflammation was observed. Antibodies against Hu23F2G were not detected. The neurologic examinations were stable except for 1 subject who had worsening weakness associated with an infection. No significant changes were noted on brain MRI scans. CONCLUSIONS: Hu23F2G was tolerated at doses that achieved high degrees of leukocyte CD11/CD118 saturation with in vivo inhibition of leukocyte migration. Because this phase I study was not designed to determine the clinical efficacy of Hu23F2G, further studies are needed.

Adult↗
PubMed1998

Neutrophil transfusions: kinetics and functions of neutrophils mobilized with granulocyte-colony-stimulating factor and dexamethasone.

BACKGROUND: The collection of adequate numbers of neutrophils (polymorphonuclear leukocytes, PMNs) from normal donors has long hampered the development of neutrophil transfusion therapy. The stimulation of donors with granulocyte-colony-stimulating factor (G-CSF) plus dexamethasone is a promising way of improving PMN collections. STUDY DESIGN AND METHODS: Sixteen normal subjects received G-CSF (600 micrograms subcutaneously) and dexamethasone (8 mg by mouth) 12 hours before leukapheresis. Measurements included PMN morphology, immunophenotype analysis, chemiluminescence, bactericidal activity, in vivo kinetics, and adverse effects. RESULTS: A mean of 77.4 +/- 6.4 x 10(9) PMNs was collected with each leukapheresis; 14 percent were bands. PMNs had increased surface expression of CD11b, CD18, CD14, CD32, and CD64. Bactericidal capacity against Staphylococcus aureus was normal. Inducible respiratory burst was maintained, although the responses to some agonists were diminished. Returned leukapheresis cells labeled with 3H-diisopropylfluorophosphate had a modestly decreased percentage of recovery and circulated with a prolonged half-life. Migration of these cells to skin chambers was approximately equal to that of the subjects' own blood PMNs. Adverse effects included transient bone pain, headache, hunger, and insomnia. CONCLUSIONS: Precollection treatment of leukapheresis donors with G-CSF plus dexamethasone is an effective way to enhance the collection of PMNs with normal or near-normal functional properties for PMN transfusion therapy.

Adult↗
PubMed1998

Immune and idiopathic neutropenia.

Neutropenia is often attributed to immunologically mediated injury to mature neutrophils or their precursors. Clinically it is useful to classify immune mediated neutropenias as isoimmune, autoimmune (including some drug-associated neutropenias), and idiopathic (cases possibly with an immune mechanism). Isoimmune neutropenia occurs in infancy and the antigen and is an isoform of CD16. This condition usually resolves spontaneously. For other forms of immune neutropenia the antigens are not yet well defined and the diagnosis is usually based on clinical criteria. In these patients availability of granulocyte macrophage colony-stimulating factor is a major advance; most respond quickly to treatment with this growth factor.

Autoimmune Diseases↗
PubMed1998

The discovery, development and clinical applications of granulocyte colony-stimulating factor.

The story of the discovery, development and applications of G-CSF illustrates many of the best features of modern laboratory and clinical investigation. The initial discovery of the CSFs was somewhat serendipitous. The pathway to understanding the cellular and molecular base for the action of these substances was long, but fruitful and exciting for those who pursued it tirelessly. The power of modern molecular biology is illustrated by the rapid advances which followed the cloning of the G-CSF gene. Major advances in our understanding of the regulation of neutrophil production and deployment have followed, together with many important clinical observations. To date hundreds of thousands of patients have been treated with G-CSF and some individuals with severe chronic neutropenia have received daily therapy for more than ten years. Results of recent studies suggest that there will be many more interesting and important clinical applications for G-CSF.

Animals↗