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

Monoamine 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 double-fluorescence confocal microscopy. VMAT2-positive cells in the subepidermal layer were identified as mast cells by their expression of tryptase. Neoplastic mast cells in all cases of cutaneous mastocytosis retained their VMAT2 positivity. The intraepidermal VMAT2-expressing cells were identified as Langerhans cells by their CD1a positivity. VMAT2 was absent from Langerhans cell histiocytosis. VMAT2 is an excellent marker for normal and neoplastic mast cells. The expression of VMAT2 demonstrates the capacity of mast cells for monoamine storage and handling. The presence of VMAT2 in epidermal Langerhans cells revealed a previously unrecognized monoamine-handling phenotype of these cells and indicates possible involvement of amine storage and release associated with antigen presentation. Absence of VMAT2 in neoplastic Langerhans cells indicates a loss of monoamine handling capacity of these cells during tumorigenesis.
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PMID: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. 1515 Feb 86

Pulmonary Langerhans' cell histiocytosis (PLCH) is a disease characterized by the occurrence of complex fibro-cellular interstitial lesions dominated by Langerhans' cells (LC), which occurs predominantly in young adult smokers. We undertook this retrospective study to better define the lymphohistiocytic cell populations in PLCH in order to obtain a greater insight into its pathogenesis. Formalin-fixed, paraffin-embedded, surgically excised, archival lung tissue from seven patients (two males, five females; average age 34.9 years) was immunostained with a panel of antibodies for lymphohistiocytic markers: CD1a, CD3, CD4, CD8, CD15, CD20, CD56, TIA-1, CD68-PGM1, Mac387, and mast cell tryptase. Double immunolabeling was performed with CD1a/Mac387. Leder cytochemical stain for chloroacetate esterase was also performed. A moderate number of lymphocytes, predominantly T lymphocytes, were scattered diffusely within the lesions. The mean CD4/CD8 ratio was 0.1/1. The CD3/CD8 ratio (1.18/1) substantiated the CD4/CD8 ratio. The CD8 subset was CD56-negative and TIA-1-positive, indicating a cytotoxic T lymphocyte phenotype. CD68-PGM1 was strongly positive in alveolar macrophages (AM) and weakly stained LC. Mac387, a marker of activated macrophages, weakly stained AM, while highlighting other interstitial cells. These interstitial cells appeared not to be LC (substantiated by CD1a/Mac387 dual labeling) or CD68-PGM-1-positive macrophages. Having excluded mast cells (positive with mast cell tryptase) and neutrophils (positive with CD15 and Leder stains), there appeared to be a residual population of non-Langerhans cell monocytoid cells (NLMC), which were Mac 387+, CD68-PGM1-, Mast cell tryptase-, CD15-, and CD1a-. Our results showed a predominance of CD8+, TIA-1+ cytotoxic T lymphocytes among the lymphocyte subsets which appear to interact with LC and AM in PLCH lesions. A small sub-population of NLMC was also present. Further studies are required to better define and to evaluate the role of cytotoxic T cells and NLMC in the pathogenesis of PLCH.
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PMID:Lymphocyte sub-populations and non-Langerhans' cell monocytoid cells in pulmonary Langerhans' cell histiocytosis. 1833 20

An 11-year old Caucasian female with a remote history of urticaria pigmentosa presented with a neck mass. A biopsy demonstrated a large intradermal nodule composed of unusually large epithelioid mast cells, including a prominent subset with bi-lobed and multi-lobed nuclei. By immunohistochemistry, the cells expressed CD117 (C-Kit), mast cell tryptase, CD68, and CD25, and were negative for CD163, CD1a, and S-100, confirming the diagnosis of mastocytoma. Equally prominent was an admixed infiltrate of CD68 and CD163-positive xanthomatous histiocytes that included Touton-type giant cells. Eosinophils were abundant. At 7 months follow-up, there was no recurrence of the lesion following complete excision. However, given the unusual cytologic features, close clinical observation is warranted, as the long-term biologic potential of mastocytoma with this degree of cytologic atypia is uncertain. Awareness of this unusual morphologic variant is also important as the histologic features may mimic such childhood neoplasms as juvenile xanthogranuloma and Langerhans cell histiocytosis.
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PMID:Histiocyte-rich pleomorphic mastocytoma: an uncommon variant mimicking juvenile xanthogranuloma and Langerhans cell histiocytosis. 1960 70

In view of the similarity of clinicopathological features between reactive lesions of the oral cavity, the objective of the present study was to investigate the density of MCs (mast cells) and microvessels in a series of these lesions. Thirty-seven cases of reactive lesions including fibrous hyperplasia (FH, n=10), inflammatory fibrous hyperplasia (IFH, n=10), peripheral giant cell lesion (PGCL, n=10) and lobular capillary hemangioma (LCH, n=7) were investigated using immunohistochemistry for mast cell tryptase and CD34. For comparative purposes, central giant cell lesions (CGCL, n=5) were included. A higher MC density was observed in LCH (37.01), while CGCL exhibited the lowest density (n=8.14). There was a significant difference in MC density when all reactive lesions were compared to CGCL (p=0.001). The largest mean density of microvessels was observed in LCH (n=21.69). The smallest number was observed in CGCL (n=6.24). There was a significant difference in microvessel density when the reactive lesions were compared to CGCL (p=0.003). There was a significant and direct correlation between the density of MCs and microvessels only for IFH (p=0.048) and CGCL (p=0.005). A significant and direct correlation between the mean density of MCs and microvessels was observed when the reactive lesions were analyzed as a whole (p=0.005). Our results suggest that mast cells contribute to the connective tissue framework and angiogenic function, as well as the development, of reactive lesions of the oral cavity, including FH, IFH, LCH and PGCL.
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PMID:Involvement of mast cells and microvessels density in reactive lesions of oral cavity: A comparative immunohistochemical study. 2749 2