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)

1 The mechanisms by which agents modulate the induction of kinin B1-receptors were investigated by studying the effects of kinins in vitro, by use of the rabbit isolated aorta, and in vivo by measuring the blood pressure of anaesthetized rabbits. 2 The contractile response of the rabbit isolated aorta to kinins increased in a time-dependent manner in vitro. This effect was abolished by continuous exposure to the protein synthesis inhibitor cycloheximide (71 microM). 3 Several substances were found to increase specifically the rate of sensitization to des-Arg9-bradykinin (des-Arg9-Bk), when applied continuously in vitro to tissues isolated from normal animals: bacterial lipopolysaccharide (LPS; 1 micrograms ml-1), muramyl-dipeptide (MDP; 2 micrograms ml-1), phorbol myristate acetate (PMA; 320 nM), epidermal growth factor (EGF; 100 ng ml-1) and endothelial cell growth factor (150 micrograms ml-1). 4 The protease inhibitors phenylmethylsulphonyl fluoride and aprotinin, a non-adjuvant isomer of MDP, rabbit purified leukocyte interferon, fibroblast growth factor and the chemotactic peptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) did not have this effect. 5. It has been demonstrated that LPS induces B1-receptors in rabbits enabling des-Arg9-Bk to act as a hypotensive agent. In these experiments neutropenia induced by nitrogen mustard, did not prevent the in vivo effect of LPS. MDP (300 micrograms) and PMA (100 micrograms) were also found to induce a state of responsiveness to des-Arg9-Bk in vivo. FMLP (1 mg i.v.) induced a temporary decrease in blood neutrophil counts but had no effect on the induction of responses to des-Arg9-Bk. 6. The development of responses mediated by the B,-receptor in the two experimental systems seems to be unrelated to the activation of neutrophil leukocytes, but may be related to the activation of tissue macrophages. Approximately 3% of cultured adherent cells derived from rabbit aorta strips following protease digestion were stained for non-specific esterase, supporting such a possibility.
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PMID:Studies on the induction of pharmacological responses to des-Arg9-bradykinin in vitro and in vivo. 367 93

The anti-inflammatory effects of gold compounds include suppression of PMN lysosomal enzyme release. Since lysosomal products can provoke PMN aggregation, we assessed the effect of two gold compounds, auranofin and GST, on suppressing aggregation, degranulation, and metabolic functions of the cells. Aggregation of 1 x 10(7) cytochalasin B-treated PMNs in response to 2 x 10(-7)M FMLP, as assessed by light scattering, was inhibited in a dose-dependent fashion by both drugs. Concentrations of auranofin ranging from 5 to 20 microM caused 30.8% to 89% inhibition, whereas 200 microM GST reduced aggregation by only 32%. FCS or BSA added to suspensions of normal PMNs considerably reduced the gold compound inhibitory effect on PMN aggregation. Cell viability assessed by dye exclusion and lactate dehydrogenase release was unaffected by the drugs. The suppressive activities of the drugs could not be removed by washing the PMNs. Correspondingly, the drugs suppressed lysosomal enzyme release induced by FMLP of PMNs rendered secretory with cytochalasin B. Concentrations of 20 microM auranofin and 200 microM GST resulted, respectively, in a 61.5% and 19.3% reduction of release of lysozyme, 61.7% and 27.1% reduction of beta-glucuronidase, 84.8% and 33.7%s reduction of myeloperoxidase, and 50.0% and 25.0% reduction of lactoferrin. Furthermore, auranofin inhibited 14C-1-glucose oxidation through the hexose monophosphate shunt in response to stimulation by either PMA or methylene blue. The in vivo studies suggested that auranofin could prevent neither neutropenia induced by zymosan-activated serum nor a corresponding rise in plasma lactoferrin levels. These findings suggest that the beneficial effect of gold compounds in rheumatoid arthritis are unlikely to be related to their ability to dampen PMN activation in vivo.
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PMID:Correlation of in vitro and in vivo effects of gold compounds on leukocyte function: possible mechanisms of action. 628 1

To extend our studies about phenotypical and functional alterations of G-CSF-induced neutrophils we have evaluated their light-scatter profile, mobilization of intracellular calcium ([Ca2+]i) and membrane depolarization after stimulation. A significant increase in the forward scatter signals could be demonstrated in such neutrophils from patients with neutropenias of various origin and from healthy test subjects. This increase began 4 h and returned to normal 96 h after G-CSF injection in the latter group. We found an impairment of [Ca2+]i mobilization in neutrophils from patients with glycogen storage disease type IB after stimulation of these cells with fMLP. It was even more pronounced than in severe congenital neutropenia (SCN). However, [Ca2+]i fluxes were normal when ionomycin was used. Neutrophils from patients with cyclic neutropenia (cyNP) and chemotherapy-induced neutropenia (chNP) mobilized [Ca2+]i similar to those from healthy donors. Furthermore, we found a decreased percentage of neutrophils depolarizing after stimulation with fMLP and PMA in patients with SCN, whereas membrane depolarization was normal in patients with chNP and cyNP. All the alterations found here are suggested to be caused by a partial immaturity of the neutrophils, although in vivo activation and a direct effect of G-CSF on myeloid precursors might be involved.
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PMID:Changes in light-scatter profile, membrane depolarization and calcium mobilization of neutrophils induced by G-CSF in vivo. 752 31

Severe congenital neutropenia (SCN) can be corrected in vivo by treatment with pharmacological dosages of recombinant human granulocyte colony-stimulating factor (rhG-CSF). In order to analyze the decreased chemotaxis of neutrophils from SCN patients receiving rhG-CSF, neutrophil functions essential for chemotaxis were investigated. The mobilization of cytosolic calcium ([Ca2+]i) and the functional state of cytoskeletal proteins in neutrophils from SCN patients were compared with either neutrophils from healthy donors (or, in selected experiments, from patients with cyclic neutropenia) and neutrophils from patients with chemotherapy-induced neutropenia also receiving rhG-CSF. Using flow cytometric analysis, two neutrophil subpopulations were detected in SCN patients in response to N-formylmethionine leucyl-phenylalanine (FMLP) (10(-9) M to 10(-7) M), one of which was unable to respond to this stimulus with an increase in [Ca2+]i. Whereas a homogeneous increase in [Ca2+]i in normal neutrophils occurred at 10(-9) M FMLP, neutrophils from SCN patients required 10(-6) M FMLP to respond homogeneously with an increase in [Ca2+]i. In contrast, G-CSF induced neutrophils from patients with cyclic neutropenia and from patients with chemotherapy-induced neutropenia showed a normal increase in [Ca2+]i after stimulation. The [Ca2+]i-dependent superoxide anion (O2-) generation in response to FMLP was also significantly diminished in neutrophils from SCN patients compared to normal neutrophils. However, O2- generation elicited by phorbolester (PMA), which directly activates protein kinase C (PKC), was not affected in SCN neutrophils. The total immunoreactive actin content and basal F-actin content in neutrophils from SCN patients were elevated as compared to normal neutrophils and neutrophils from patients with chemotherapy-induced neutropenia. The increase in F-actin content following FMLP activation was much lower in neutrophils from SCN patients as compared with normal neutrophils. These data suggest a defect in the signal transduction pathway in neutrophils from SCN patients between FMLP ligand-receptor interaction and Ca2+ mobilization, whereas upstream of PKC, triggered events seem to be unaffected. Therefore, [Ca2+]i-dependent neutrophil function in response to FMLP, such as actin disassembly, chemotaxis and O2- generation are diminished in SCN neutrophils. The pathomechanism responsible for the defective [Ca2+]i increase might be an initial step in understanding the underlying pathophysiology of SCN.
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PMID:Abnormal regulation in the signal transduction in neutrophils from patients with severe congenital neutropenia: relation of impaired mobilization of cytosolic free calcium to altered chemotaxis, superoxide anion generation and F-actin content. 767 87

Increased susceptibility to infections in patients with myelodysplastic syndromes (MDS) is thought to be due to neutropenia as well as functional abnormalities of neutrophils. In the present study we examined the effect of two different stimulants (fMLP, PMA) and three cytokines (alphaTNF, G-CSF and GM-CSF), both singly and in combination on granulocyte (RB) in 25 MDS patients compared to seven healthy controls. Single fMLP and PMA-stimulation showed similar results for both groups. Preincubation with cytokines enhanced fMLP-stimulated RB in most MDS patients and controls, but in patients to a significantly lesser extent when compared to the control group (p < or = 0,05). Combinations of alphaTNF + GM-CSF and alphaTNF + G-CSF were highly synergistic in priming fMLP-stimulated burst in both groups. But again, as with the single cytokine priming this effect was markedly reduced in MDS patients compared to controls (p < or = 0,05). A specific priming defect for one of the cytokines or a cytokine combination could not be demonstrated. Serum alphaTNF levels were measured in 18 and neutrophil alkaline phosphatase (NAP) index in 23 patients. Results did not correlate with variations of the RB in MDS patients. We conclude that reduced alphaTNF, GM-CSF and G-CSF priming of granulocyte RB is a frequent finding in MDS and may contribute to the enhanced susceptibility to bacterial infections.
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PMID:Cytokine priming of the granulocyte respiratory burst in myelodysplastic syndromes. 937 5

The function of neutrophil can be evaluated by measuring oxidative metabolism using chemiluminescence, tetrazolium dye reduction or the others. Those results are not always satisfactory which would be caused by subtle difference in each preparation of the reagents and the lack of reproducibility. Recently, flow cytometric procedures for semi-quantitating superoxide production in neutrophils have been developed to evaluate their function. This procedure, which requires only small amount of whole blood, can easily and rapidly yield reproducible and reliable data. In this study, we optimized analytical conditions and then determined reference interval to evaluate neutrophil function of patients with various disorders. Optimal concentrations and incubation times of DCFH-DA and PMA were 5 mumol/l for 15 minutes and 25 micrograms/ml for 20 minutes, respectively. Production of superoxide in neutrophil was represented by relative fluorescence intensity(RFI) with assay coefficient of variance(CV) of 4.0-11.1%. Neutrophils had to be examined within 2 hours after venipuncture to obtain reliable data. Reference interval was determined as 170.4 +/- 58.7(mean +/- SD) RFI. Neutrophil function of patients with neutropenia, paroxysmal nocturnal hemoglobinuria(PNH), renal failure, systemic lupus erythematosus(SLE), myeloperoxidase deficiency, myelodysplastic syndrome(MDS), and diabetes mellitus were within the reference interval as evaluated by this method. Only neutrophils of chronic granulomatous disease, which is known to give clearly low superoxide production, showed actually decreased value. These results indicate that this procedure would be clinically useful for diagnosis of patient with impaired neutrophil function.
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PMID:[Determination of neutrophil function by measuring superoxide production with whole blood flow cytometry]. 939 45

Preclinical studies have demonstrated that recombinant IFN-alpha (rIFN-alpha) can enhance the tumor associated glycoprotein 72 (TAG-72) on tumors. To determine whether rIFN-alpha could enhance TAG-72 expression in vivo in patients, 15 women with breast cancer were randomized to receive daily injections of rIFN-alpha (3 x 10(6) units/m2 for 14 days) beginning on day 1 (group 1 = 7 patients) or on day 6 (group 2 = 8 patients). On day 3, all patients received a 10-20-mCi tracer dose of 131I-CC49, a high-affinity murine monoclonal antibody reactive against TAG-72, followed by a therapy dose of 60-75 mCi/m2 of 131I-CC49 on day 6. Whole body and single-photon emission computed tomography scans along with whole blood pharmacokinetics were performed following tracer and treatment phases. Hematological toxicity was considerable; reversible grade 3-4 neutropenia and thrombocytopenia was observed in 12 of 15 patients. Twelve of 14 patients tested developed human antimouse antibodies 3-6 weeks after treatment. For group 1 patients, whole blood residence time increased significantly between that predicted from the tracer doses and therapy doses (42.6 +/- 4.7 versus 51.5 +/- 4.8 h, respectively; P < 0.01). The calculated radiation absorbed dose to red marrow from therapy compared to tracer activity was also significantly higher for this group (1.25 +/- 0.35 versus 1. 07 +/- 0.26 cGy/mCi; P < 0.05). Treatment with rIFN-alpha was found to enhance TAG-72 expression in tumors from patients receiving rIFN-alpha (group 1) by 46 +/- 19% (P < 0.05) compared to only 1.3 +/- 0.95% in patients not initially receiving IFN (group 2). The uptake of CC49 in tumors was also significantly increased in rIFN-alpha-treated patients. One partial and two minor tumor responses were seen. In summary, rIFN-alpha treatment altered the pharmacokinetics and tumor uptake of 131I-CC49 in patients at the expense of increased toxicity.
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PMID:Effect of recombinant alpha-interferon on pharmacokinetics, biodistribution, toxicity, and efficacy of 131I-labeled monoclonal antibody CC49 in breast cancer: a phase II trial. 981 42

The combination of COL-1 (anti-CEA) and CC49 (anti-TAG-72) has shown an increase in binding and distribution in colon cancer by immunoperoxidase staining compared to either antibody alone. To overcome tumor heterogeneity and allow delivery of higher radiation dose, 131I-labeled COL-1 and CC49 at a total dose of 75 mCi/m2 (2775 MBq/m2) were simultaneously administered to 14 patients with metastatic colon cancer. alpha-IFN (3 x 10(6) IU) was given s.c. on days -5 to +3 to increase carcinoembryonic antigen and TAG-72 antigen expression. Most patients had mild symptoms during IFN therapy, including mild neutropenia, fever, and malaise, which rapidly subsided after IFN cessation. No acute allergic reactions occurred with radioimmunotherapy; two patients experienced transient, delayed grade 2 arthralgias. Transient neutropenia and/or thrombocytopenia, which was maximal at 4-6 weeks, were consistent side effects without adverse events. All patients had tumor localization, and 13 of 14 patients achieved 4+ (highest grade) localization readings to at least one known site of disease. No objective responses occurred; 4 patients were stable and 10 progressed. Tumor dose estimates varied from 393 to 1327 cGy, including liver and extrahepatic sites. Combining two complementary antibodies and IFN administration appeared to increase localization intensity and radiation doses at tumor sites as compared to historical controls. The amount of radiation delivered to tumor sites was still below that required to cause tumor regressions in metastatic colorectal cancer.
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PMID:Phase II study of dual 131I-labeled monoclonal antibody therapy with interferon in patients with metastatic colorectal cancer. 981 34

Protein kinase C (PKC) plays an important role in the cell signal transduction of many physiological processes. In contrast to these physiological responses, increases in PKC activity have also been associated with inflammatory disease states, including ulcerative colitis. The objective of this study was to examine the role of PKC as a causative mediator in initiation of experimentally induced colitis in the rat. Colitis was induced in rats by intrarectal (0.6 ml) instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS; 75 mg/kg in 50% ethanol) or the PKC activator phorbol 12-myristate 13-acetate (PMA; 1.5-3.0 mg/kg in 20% ethanol). Gross and histological mucosal damage, mucosal neutrophil infiltration, mucosal PKC activity, and PKC protein content for PKC isoforms alpha, beta, delta, and epsilon were assessed 2 h to 14 days after an inflammatory challenge. Both PKC activity and mucosal injury increased significantly within 4 h of TNBS treatment. PKC activity was maximal at 7 days and declined at 14 days, whereas mucosal damage became maximal at 1 day and declined after 7 days. In contrast, neutrophil infiltration as assessed by myeloperoxidase activity only increased 12 h after TNBS treatment, became maximal 1 day after TNBS administration, and declined thereafter. PKCbeta, -delta, and -epsilon were increased in response to TNBS, whereas PKCalpha protein content was decreased. The PKC antagonists staurosporine and GF-109203X (25 ng/kg iv) reduced TNBS-induced changes in mucosal PKC activity and the degree of mucosal damage. In contrast, neutropenia induced by antineutrophil serum treatment did not significantly affect the degree of injury or mucosal PKC activity. Furthermore, activation of mucosal PKC activity with PMA also induced mucosal damage, which was also inhibited by pretreatment with a PKC antagonist. In conclusion, these results suggest that increases in PKC activity play a causative role in TNBS-induced colitis. The PKC-mediated response to TNBS does not appear to involve neutrophil infiltration.
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PMID:Protein kinase C mediates experimental colitis in the rat. 1007 33

The tumor-associated glycoprotein 72 (TAG-72) antigen is present on a high percentage of tumor types including ovarian carcinomas. Antibody B72.3 is a murine monoclonal recognizing the surface domain of the TAG-72 antigen and has been widely used in human clinical trials. After our initial encouraging studies (M. G. Rosenblum et al., J. Natl. Cancer Inst., 83: 1629-1636, 1991) of tissue disposition, metabolism, and pharmacokinetics in 9 patients with ovarian cancer, we designed an escalating dose, multi-arm Phase I study of 90Y-labeled B72.3 i.p. administration. In the first arm of the study, patients (3 pts/dose level) received an i.p. infusion of either 2 or 10 mg of B72.3 labeled with either 1, 10, 15, or 25 mCi of 90Y. Pharmacokinetic studies demonstrated that concentrations of 90Y-labeled B72.3 persist in peritoneal fluid with half-lives >24 h after i.p. administration. In addition, 90Y-labeled B72.3 was absorbed rapidly into the plasma with peak levels achieved within 48 h, and levels declined slowly thereafter. Cumulative urinary excretion of the 90Y label was 10-20% of the administered dose which suggests significant whole-body retention of the radiolabel. Biopsy specimens of bone and marrow obtained at 72 h after administration demonstrated significant content of the label in bone (0.015% of the dose/g) with relatively little in marrow (0.005% of the dose/g). The maximal tolerated dose was determined to be 10 mCi because of hematological toxicity and platelet suppression. This typically occurred on the 29th day after administration and was thought to be a consequence of the irradiation of the marrow from the bony deposition of the radiolabel. In an effort to suppress the bone uptake of 90Y, patients were treated with a continuous i.v. infusion of EDTA (25 mg/kg/12 h x 6) infused immediately before i.p. administration of the radiolabeled antibody. Patients (3 pts/dose level) were treated with doses of 10, 15, 20, 25, 30, 35, 40, or 45 mCi of 90Y-labeled B72.3 for a total of 38 patients. EDTA administration resulted in significant myeloprotection, which allowed escalation to the maximal tolerated dose of 40 mCi. Dose-limiting toxicity was thrombocytopenia and neutropenia. Studies of plasma and peritoneal fluid pharmacokinetics demonstrate no changes compared with patients without EDTA pretreatment. Cumulative urinary excretion of the radiolabel was not increased in patients pretreated with EDTA compared with the untreated group. However, analysis of biopsy specimens of bone and marrow demonstrated that bone and marrow content of the 90Y label was 15-fold lower (<0.001% injected dose/g) than a companion group without EDTA. Four responses were noted in patients who received 15-30 mCi of 90Y-labeled B72.3 with response durations of 1-12 months. These results demonstrate the myeloprotective ability of EDTA, which allows safe i.p. administration of higher doses of 90Y-labeled B72.3 and, therefore, clearly warrant an expanded Phase II trial in patients with minimal residual disease after standard chemotherapy or for the palliation of refractory ascites.
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PMID:Phase I study of 90Y-labeled B72.3 intraperitoneal administration in patients with ovarian cancer: effect of dose and EDTA coadministration on pharmacokinetics and toxicity. 1035 26


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