Search results for "Merkel cell"

Distribution and coexistence of chromogranin A-, serotonin-and pancreastatin-like immunoreactivity in endocrine-like cells of the human anal canal

1992

The comparative distribution and coexistence of chromogranin A (CGA)-, serotonin (5-hydroxytryptamine; 5-HT)- and pancreastatin (PST)-like immunoreactivity in endocrine-like cells of the human anal canal was investigated by light-microscopic immunocytochemistry. The largest population of colorectal endocrine-like cells consisted of CGA-immunoreactive (ir) cells, followed by the 5-HT-ir and PST-ir cell population. In the anal transitional zone (ATZ), CGA- and 5-HT-immunoreactivity was equally distributed; ir-PST was confined to a smaller endocrine-like cell population. In the squamous zone and the perianal skin, Merkel cells in the basal layer of the epidermis and hair follicles exhibited ir…

Electron microscopic immunogold cytochemistry reveals chromogranin A confined to secretory granules of porcine Merkel cells

1990

By ultrastructural immunohistochemistry using the immunogold technique, immunoreactive (ir) Chromogranin A (CGA) was found to be confined to the secretory vesicles of porcine Merkel cells. CGA was present predominantly in the periphery of the electron-dense core and on the clear halo. These findings indicate that CGA is a regular constituent of Merkel cell secretory granules but probably not exclusively responsible for their electron opacity.

Chromogranin A in the Mammalian Merkel Cell: Cellular and Subcellular Distribution

1989

Chromogranin-A (CGA), which accounts for more than half the soluble matrix protein in secretory granules of various neuroendocrine cells, has a wide spectrum of potential biological roles and is considered an important marker of the diffuse neuroendocrine system (DNES). Light and electron microscopic immunohistochemistry of mammalian skin revealed that Merkel cells are exclusively CGA-immunoreactive (ir) and that the immunoreaction is localized in the secretory granules. This finding supports the classification of the Merkel cell as a member of the DNES. The CGA immunoreactivity was restricted to Merkel cells of pigs and humans. In human embryonic skin, CGA was expressed in Merkel cells as …

Chapter 20 Multiple messenger candidates and marker substances in the mammalian Merkel cell – axon complex: a light and electron microscopic immunohi…

1988

Publisher Summary This chapter discusses multiple messenger candidates and marker substances in the mammalian merkel cell—axon complex. According to the APUD theory, cells of the diffuse neuroendocrine system (DNES) are essentially characterized by containing amines, peptides and marker substances like neuronspecific enolase (NSE) and chromogranin A (CGA). By the comparison of the histotopography of immunostained peptides, CGA and neuroendocrine markers, there was an expectation to find out the most appropriate immunohistochemical marker of the Merkel cell and to get further insight into the complex chemo-anatomy and possible functional spectrum of the Merkel cell -axon complex at various d…

Merkel cell carcinoma‐derived Erysipelas carcinomatosum

2019

S2k guidelines for Merkel cell carcinoma (MCC, neuroendocrine carcinoma of the skin) – update 2018

2019

Merkel cell carcinoma (MCC, ICD-O M8247 / 3) is a rare malignant primary skin tumor with epithelial and neuroendocrine differentiation. The neoplastic cells share many morphological, immunohistochemical and ultrastructural characteristics with Merkel cells of the skin. The diagnosis of MCC is rarely made on clinical grounds. Histological and immunohistochemical studies are usually required to confirm the clinical suspicion. Given the frequent occurrence of occult lymph node metastasis, sentinel lymph node biopsy should be performed once distant metastasis has been ruled out by cross-sectional imaging. Primary tumors without evidence of organ metastases are treated with complete surgical exc…

Brief S2k guidelines - Merkel cell carcinoma

2013

Jurgen C. Becker, Chalid Assaf, Dirk Vordermark, Sven N. Reske, Jorg Hense, Therese Dettenborn, Oliver Seitz, Stephan Grabbe (1) Division of General Dermatology, Graz University Hospital, Austria (2) Department of Dermatology, HELIOS Klinikum, Krefeld, Germany (3) Department of Radiotherapy, University Hospital Halle (Saale), Germany (4) Department of Nuclear Medicine, University Hospital Ulm, Germany (5) Department of Internal Medicine, University Hospital Essen, Germany (6) Department of Plastic Surgery, Hornheide Clinic, Munster, Germany (7) Department of Oral and Maxillofacial Surgery, University of Frankfurt Hospital, Germany (8) Department of Dermatology, Mainz University Hospital, Ge…