Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Proliferation and differentiation of hematopoietic progenitor cells are regulated by a network of stimulatory and inhibitory cytokines. An understanding of the molecular mechanisms of growth control may provide a physiologic basis for the innovative therapy of bone marrow disorders. Among various accessory cells, bone marrow T lymphocytes are capable of stimulating, as well as inhibiting, hematopoietic progenitor cells. We have now elucidated molecular mechanisms regulating the differential expression of T cell genes encoding for the stimulatory and inhibitory hematopoietic programs. Stimulation of hematopoiesis requires granulocyte-macrophage colony stimulating factor (GM-CSF), whereas inhibition requires interferon-gamma (IF gamma). Both cytokines can be induced by interleukin-2 (IL2). The T cell IL2 receptor consists of a 75 kD chain (p75) mainly expressed on a subset of resting T cells and a 55 kD chain (p55) which is strongly expressed upon T cell activation. P55 and p75 associate on activated T cells to form a dimeric receptor molecule exhibiting high affinity for IL2. The p75 monomer has an intermediate affinity for IL2. Expression of p55 in the context of the high affinity IL2 receptor constitutes a requirement for T cell IFg release. In contrast, p75 alone is capable of mediating the production of GM-CSF. Thus, T cells may be capable of selective production of cytokines with specific effects in hematopoietic growth control. Utilizing a human peripheral blood leukocyte genomic library, we identified various clones containing the entire GM-CSF gene, including coding and regulatory regions. Cloning of the GM-CSF gene allowed clinical studies utilizing recombinant DNA-derived GM-CSF. Chemotherapy-induced neutropenia contributes to both complications of cytotoxic therapy as well as increased relapse incidence of underlying disease. In a prospective randomized study, we have demonstrated that GM-CSF abrogates neutropenia following aplasiogenic chemotherapy in children and adolescents with solid tumors, and that GM-CSF may reduce the duration of infectious episodes after cytotoxic therapy. Next, we escalated the cumulative doses of cytotoxic therapy in an ablative regimen followed by hematopoietic stem cell transplantation to treat patients with poor prognosis pediatric tumors. Morbidity of this highly toxic ablative regimen depends on the duration of myeloid aplasia. Median duration of aplasia following hyper-VAMP was 13 days with CM-CSF and 29 days without GM-CSF. In addition, we have employed p55 blocking monoclonal antibody for prevention of graft vs. host disease in bone marrow transplantation. The understanding of specific molecular mechanisms of hematopoietic immuno-regulation can thus be utilized to provide novel approaches to the treatment of bone marrow failure and cancer.
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PMID:Molecular regulation of hematopoietic cytokines: implications and indications for clinical use in pediatric oncology. 130 80

We report here the case of a 55-year-old patient with chronic granular lymphocyte disorder associated with moderate neutropenia. The majority of peripheral blood lymphocytes displayed a CD3-, CD8-, CD16+, CD56(NKH1)- phenotype. The patient's cells showed high spontaneous cytotoxic activity against K562 targets and developed the ability to kill the natural killer (NK)-resistant target Daudi following activation with interleukin 2 (IL-2). Simultaneously, IL-2 induced proliferation of these cells, albeit to a low level. The effects of IL-2 are likely to be mediated through the IL-2R beta chain (p70) which is expressed on these cells in the absence of the IL-2R alpha chain (p55, Tac). IL-4 was demonstrated to be inhibitory of both the cytotoxic and proliferative effects of IL-2. Thus, despite an unusual CD56- phenotype, the expanded lymphocyte population in this patient display functional and phenotypic properties of normal, non-activated NK cells. These cells probably represent the counterpart of a minor NK cell subpopulation, present in normal individuals at a low frequency, and which has never been fully characterized functionally. In addition, we show that the cytolytic activity of this NK cell population can be blocked in vitro in the presence of a cAMP analog or of theophylline, possibly providing new means of investigating the role of NK cell cytotoxicity on the pathogenesis of associated symptoms in such patients.
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PMID:In vitro responsiveness to interleukins and theophylline of CD16+, CD56- natural killer cells in a patient with chronic granular lymphocyte disorder. 137

Serum levels of inflammatory cytokines and chemokines were measured in 132 patients with chronic idiopathic neutropenia of adults (CINA) and 34 healthy volunteers (controls) using commercially available micro-ELISA determination kits. We found that serum interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), transforming growth factor-beta(1) (TGF-beta(1)), and soluble tumor necrosis factor receptor p55 (sTNF-RI) were all significantly increased in CINA patients compared to controls. Individual cytokine values inversely correlated with the number of circulating neutrophils. Serum levels of interleukin-8 (IL-8) and RANTES, two potent chemokines for neutrophils and lymphocytes, respectively, were also significantly increased in the group of patients and they inversely correlated with the number of circulating neutrophils. Contrarily, serum levels of interleukin-4 (IL-4), interferon-gamma (IFN-gamma), soluble CD23 (sCD23), and soluble interleukin-2 receptor (sIL-2R) did not show any significant change in the patients studied. We assume that CINA patients have increased serum concentrations of inflammatory cytokines and chemokines mainly produced by activated macrophages, while they disclose normal levels of inflammatory molecules mainly released from activated lymphocytes. These findings provide further evidence for an underlying low-grade chronic inflammatory process in CINA patients, as we previously have suggested. If this chronic inflammation is really the cause of the disorder or it simply represents the result of neutropenia remains to be elucidated.
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PMID:Patients with chronic idiopathic neutropenia of adults have increased serum concentrations of inflammatory cytokines and chemokines. 1107 51

Hypocholesterolemia, which often accompanies infectious diseases has been suggested to serve as a prognostic marker in hospitalized patients. Even though patients with chemotherapy-induced leukopenia are at high risk of infection and mortality, only limited information is available on serum cholesterol levels in these patients. We therefore measured serum cholesterol levels in 17 patients with hematological malignancies during chemotherapy-induced neutropenia and correlated it with clinical outcome. Patients with fever (>38.5 degrees C) showed a significant decrease in serum cholesterol levels within 24 hours. Eight days after onset of the fever non-survivors had significantly lower serum cholesterol levels (median 2.09 mmol/l, range 0.49-2.79, n=6) compared to survivors (median 3.23 mmol/l, range 1.68-4.86, n=11). Cholesterol levels in survivors returned to baseline levels at the time of discharge from the hospital. At the onset of fever, serum levels of inflammatory cytokines interleukin-6, tumor necrosis factor (TNF) and soluble TNF receptors p55 and p75 were elevated in all patients, but only TNF and TNF receptor p75 levels were significantly different in survivors and non-survivors. Our data suggest that a decrease in serum cholesterol levels is a prognostic marker in neutropenic patients with fever. Release of inflammatory cytokines may in part be responsible for hypocholesterolemia in these patients.
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PMID:Serum cholesterol levels in neutropenic patients with fever. 1200 22