The Vesicular Monoamine Transporter 2 (VMAT2) Is Expressed by Normal and Tumor Cutaneous Mast Cells and Langerhans Cells of the Skin but Is Absent from Langerhans Cell Histiocytosis

Abstract

S U M M A R YMonoamine storage in secretory granules is mediated by the vesicular monoamine transporters 1 and 2 (VMAT1 and VMAT2). The aim of our study was to identify monoamine-handling normal and neoplastic inflammatory cells in the skin by their expression of VMAT1 and VMAT2. Normal skin from various parts of the body, as well as 21 cases of cutaneous mastocytosis and 10 cases of cutaneous Langerhans cell histiocytosis were analyzed by immunohistochemistry, radioactive in situ hybridization, and doublefluorescence confocal microscopy. VMAT2-positive cells in the subepidermal layer were

Vesicular Polyamine Transporter Mediates Vesicular Storage and Release of Polyamine from Mast Cells

“…Furthermore, VMAT2 gene expression was also observed in BMMCs. Consistent with the results reported previously, marginal levels of VMAT1 expression were observed (17). Subsequently, we investigated whether VPAT protein is actually expressed in BMMCs.…”

“…It is well established that VMAT2 is specifically expressed in mast cells and is responsible for vesicular storage and release of histamine (17,23). Furthermore, it is noteworthy that VMAT1 was also expressed in BMMCs and RPMCs (Figs.…”

False-positive radio-iodinated metaiodobenzylguanidine (123I-MIBG) accumulation in a mast cell-infiltrated infantile haemangioma

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The emergence of neurotransmitters as immune modulators

“…Indeed, evidence supporting this hypothesis is provided from studying patients with Langerhans cell (LC) histiocytosis, a disorder characterized by the uncontrolled accumulation of LCs within peripheral tissues. In these patients, LCs do not express the type-2 vesicular monoamine transporter necessary for sequestration of biogenic amines from the cytosol to intracellular vesicles [63]. Thus, the capacity to sequester and, ultimately, secrete biogenic amines might contribute to the homeostatic control of DCs.…”