Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042109 (urticaria)
 6,569 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Deactivation is a phenomenon in which leucocytes exposed in vitro to a chemotactic factor in the absence of a concentration gradient are rendered relatively unresponsive to stimulation by a subsequent chemotactic gradient. In patients with idiopathic cold-induced urticaria, the elicitation of a local experimental angioedematous lesion causes the release of two chemotactic principles previously shown to deactivate leucocytes in vitro, high molecular weight neutrophil chemotactic factor (HMW-NCF) and eosinophil chemotactic factor of anaphylaxis (ECF-A), into the venous circulation draining the challenged extremity. However, biopsy specimens of lesional skin sites obtained for up to 24 hr show no infiltration of cells. For this reason, the in vitro chemotactic responsiveness of neutrophils to the chemotactic factor HMW-NCF and C5 fragments were assessed in three patients at various times after experimental challenge. Leucocytes from venous effluent draining an experimentally-induced angioedematous lesion were markedly impaired in their chemotactic responsiveness to both chemotactic factors 5 min after challenge, while cells taken from an unchallenged extremity at the same time responded normally. Cells from both arms were equally impaired in their responsiveness 1 hr later, thereby demonstrating that the chemotactic defect becomes systemic. The acquired defect was dissipated 4 hr after challenge. These data suggest that deactivation may occur in vivo and may alter host responsiveness in states where chemotactic factors are released into the circulation.
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PMID:Inhibition of neutrophil chemotaxis in association with experimental angioedema in patients with cold urticaria: a model of chemotactic deactivation in vivo. 42 42

Recent advance about pathogenesis of Idiopathic acquired Cold-induced Urticaria underline the role of Neutrophils that, drawn by a specific mast-cell factor (HMW-NCF) might characterise precise stages of disease and presumably specific histologic "subset". This factor together with the chemotactic factor for eosinophils (ECF) can determine the so called neutrophils' "deactivation". In this study we have valued the role of neutrophils in six patients with idiopathic cold-induced urticaria and in a group of control including both patients with other forms of urticaria and healthy controls. The results of our research show the absence of alterations either in cellular neutrophilic chemotaxis or the serum one. Furthermore we have been able to determine that this "deactivation" is specific for idiopathic cold-induced urticaria and that it does not happen in the other forms of physical or non urticaria.
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PMID:[Granulocytic "deactivation" in cold urticaria]. 208 20

Idiopathic acquired cold-induced urticaria has provided a model to study release of mast cell-derived chemical mediators into the blood and alterations of neutrophilic leukocyte motility. A factor chemotactic for neutrophilic leukocytes appeared in the circulation after local experimental challenge with ice. After partial purification by Sephadex G-200 gel filtration and by anion and cation exchange chromatography the neutrophil chemotactic activity was excluded on Sepharose 4B gel filtration, indicating a molecular weight in excess of 750,000. On isoelectric focusing it exhibited a neutral isoelectric point. This chemotactic factor showed preferential chemotactic activity for neutrophils and deactivated these cells in vitro and in vivo. HMW-NCF may prove to be a useful marker of mast cell activation and its release may modulate the capacity for motility of neutrophilic leukocytes in humans.
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PMID:High molecular weight neutrophil chemotactic factor: recognition, characterization, and role in the deactivation of neutrophillic leukocytes. 739 8