Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019621 (Langerhans cell histiocytosis)
 3,250 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Histiocytosis-X cells were obtained at autopsy from the lungs and lymph nodes of a patient who died of the disseminated infantile form of this disease (Letterer-Siwe disease). The ability of these cells to synthesize and release prostaglandins was investigated in culture, by prelabeling the cell lipids with [14C] arachidonic acid and measuring the subsequent release of radioactive metabolites. The cells were seen to release primarily PGD2 and thromboxane. Correlative morphologic studies ensured the purity of the cell preparations, ruling out extraneous origin of the prostaglandins from sources other than the lesional histiocytes. Electron-microscopic study confirmed that the same cells that release prostaglandins and are capable of engulfing particles also bear the Langerhans' inclusions considered to be cell markers of histiocytosis-X. The prostaglandin production profile of alveolar macrophages from an infant who died as a result of congestive heart failure, but without histiocytosis, was studied for comparison. These cells produced PGE2 and thromboxane, but not PGD2. The theoretical implications of these findings are discussed.
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PMID:Prostaglandins in histiocytosis-X. PG synthesis by histiocytosis-X cells. 697 May 20

Macrophage-derived chemokine (MDC)/CCL22 is a CC chemokine active on dendritic cells (DC), NK cells and Th2 lymphocytes. The present study was aimed at comprehensively investigating MDC production in vitro and in vivo. DC were the most potent producers of MDC among leukocytes tested. Endothelial cells did not produce MDC under a variety of conditions. Signals that induce maturation (lipopolysaccharide, IL-1, TNF, CD40 ligand, recognition of bacteria and yeast) dramatically augmented MDC production, and dexamethasone and vitamin D3 blocked it. Prostaglandin E(2), which blocked the acquisition of IL-12 production and the capacity to promote Th1 generation, did not affect MDC production. Using mass spectrometry-based techniques, DC supernatants were found to contain N-terminally truncated forms of MDC [MDC(3-69), MDC(5-69) and MD(C7-69)] as well as the full-length molecule. In vivo, CD1a(+), CD83(+), MDC(+) DC were found in reactive lymph nodes, and in Langerhans' cell histiocytosis. Skin lesions of atopic dermatitis patients showed that CD1a(+) or CD1b(+) DC, and DC with a CD83(+) phenotype were responsible for MDC production in this Th2-oriented disorder. Thus, DC are the predominant source of MDC in vitro and in vivo under a variety of experimental and clinical conditions. Processing of MDC to MDC(3-69) and shorter forms which do not recognize CCR4 is likely to represent a feedback mechanism of negative regulation.
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PMID:Dendritic cells as a major source of macrophage-derived chemokine/CCL22 in vitro and in vivo. 1124 Dec 86