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Pathophysiology of merkel cell.

Munde PB, Khandekar SP, Dive AM, Sharma A - J Oral Maxillofac Pathol (2013)

Bottom Line: MC carcinoma (MCC) is an uncommon and often aggressive malignancy and found mainly in elderly patients.Diagnosis is based on typical histological presentation on hematoxylin and eosin (H and E) stained slides together with the results of immunohistochemistry.Histologically, MCC has been classified into three distinct subtypes: Trabecular, intermediate and small cell type.

View Article: PubMed Central - PubMed

Affiliation: Departments of Oral and Maxillofacial Pathology, Vidya Shikshan Prasarak Mandal's Dental college and Research Centre, Nagpur, Maharashtra, India.

ABSTRACT
The objective of this review is to introduce Merkel cells (MCs), to provide a basic overview on the theoretical background of function, development and clinical importance of MCs. The origin of human MCs have been controversial. Some investigators believe that it is a neural crest derivate, whereas others have proposed that it is a differentiation product of the fetal epidermal keratinocytes. MCs are cells primarily localized in the epidermal basal layer of vertebrates and concentrated in touch-sensitive areas in glabrous, hairy skin and in some mucosa. In routine light microscopy, human MCs can hardly be identified. Cytokeratin 20 (CK20) is a reliable marker with highest degree of specificity. MCs can be also distinguished by electron microscopy. MC carcinoma (MCC) is an uncommon and often aggressive malignancy and found mainly in elderly patients. It occurs most frequently in the head and neck region. Diagnosis is based on typical histological presentation on hematoxylin and eosin (H and E) stained slides together with the results of immunohistochemistry. Histologically, MCC has been classified into three distinct subtypes: Trabecular, intermediate and small cell type.

No MeSH data available.


Related in: MedlinePlus

Electron micrograph of Merkel cell in the basal layer of oral epithelium. The cytoplasm of this cell is filled with small, dense vesicles situated close to an adjacent unmyelinated nerve axon. Arrowheads point to the site of the basal lamina. (Courtesy: Antonio Nanci Tencate's Oral histology- Development, Structure and function, 7 th ed. St. Louis: Missouri Mosby an imprint of Elsevier; 2008)
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Figure 2: Electron micrograph of Merkel cell in the basal layer of oral epithelium. The cytoplasm of this cell is filled with small, dense vesicles situated close to an adjacent unmyelinated nerve axon. Arrowheads point to the site of the basal lamina. (Courtesy: Antonio Nanci Tencate's Oral histology- Development, Structure and function, 7 th ed. St. Louis: Missouri Mosby an imprint of Elsevier; 2008)

Mentions: The surface of MCs appears to be attached to the basement membrane separating the epidermis from the dermis and hemidesmosomes can be observed with neurites located just below the basal lamina. MCs shows lobulations or spine-like protrusions sometimes called microvilli. These structures (up to 50 in MCs) may measure up to 2.5 mm in length (Moll et al., 2005).[8] The spine-like protrusions of highly variable length attached to the neighboring keratinocytes by relatively few, small desmosomes located on the cell body and occasionally on the dendritic processes. The ultrastructural characteristics of MCs are the dense-core secretory granules that are accumulated near the nerve fiber junction [Figure 2]. These granules have an electron-dense core, surrounded by a clear halo and a simple membrane. MCs’ granules measures about 80-120 nm (Winkelmann and Breathnach, 1973) or 100-140 nm in diameter.[11] The cytoplasm has low microscopic density and contains loosely arranged intermediate filament cytoskeleton.[14]


Pathophysiology of merkel cell.

Munde PB, Khandekar SP, Dive AM, Sharma A - J Oral Maxillofac Pathol (2013)

Electron micrograph of Merkel cell in the basal layer of oral epithelium. The cytoplasm of this cell is filled with small, dense vesicles situated close to an adjacent unmyelinated nerve axon. Arrowheads point to the site of the basal lamina. (Courtesy: Antonio Nanci Tencate's Oral histology- Development, Structure and function, 7 th ed. St. Louis: Missouri Mosby an imprint of Elsevier; 2008)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3927344&req=5

Figure 2: Electron micrograph of Merkel cell in the basal layer of oral epithelium. The cytoplasm of this cell is filled with small, dense vesicles situated close to an adjacent unmyelinated nerve axon. Arrowheads point to the site of the basal lamina. (Courtesy: Antonio Nanci Tencate's Oral histology- Development, Structure and function, 7 th ed. St. Louis: Missouri Mosby an imprint of Elsevier; 2008)
Mentions: The surface of MCs appears to be attached to the basement membrane separating the epidermis from the dermis and hemidesmosomes can be observed with neurites located just below the basal lamina. MCs shows lobulations or spine-like protrusions sometimes called microvilli. These structures (up to 50 in MCs) may measure up to 2.5 mm in length (Moll et al., 2005).[8] The spine-like protrusions of highly variable length attached to the neighboring keratinocytes by relatively few, small desmosomes located on the cell body and occasionally on the dendritic processes. The ultrastructural characteristics of MCs are the dense-core secretory granules that are accumulated near the nerve fiber junction [Figure 2]. These granules have an electron-dense core, surrounded by a clear halo and a simple membrane. MCs’ granules measures about 80-120 nm (Winkelmann and Breathnach, 1973) or 100-140 nm in diameter.[11] The cytoplasm has low microscopic density and contains loosely arranged intermediate filament cytoskeleton.[14]

Bottom Line: MC carcinoma (MCC) is an uncommon and often aggressive malignancy and found mainly in elderly patients.Diagnosis is based on typical histological presentation on hematoxylin and eosin (H and E) stained slides together with the results of immunohistochemistry.Histologically, MCC has been classified into three distinct subtypes: Trabecular, intermediate and small cell type.

View Article: PubMed Central - PubMed

Affiliation: Departments of Oral and Maxillofacial Pathology, Vidya Shikshan Prasarak Mandal's Dental college and Research Centre, Nagpur, Maharashtra, India.

ABSTRACT
The objective of this review is to introduce Merkel cells (MCs), to provide a basic overview on the theoretical background of function, development and clinical importance of MCs. The origin of human MCs have been controversial. Some investigators believe that it is a neural crest derivate, whereas others have proposed that it is a differentiation product of the fetal epidermal keratinocytes. MCs are cells primarily localized in the epidermal basal layer of vertebrates and concentrated in touch-sensitive areas in glabrous, hairy skin and in some mucosa. In routine light microscopy, human MCs can hardly be identified. Cytokeratin 20 (CK20) is a reliable marker with highest degree of specificity. MCs can be also distinguished by electron microscopy. MC carcinoma (MCC) is an uncommon and often aggressive malignancy and found mainly in elderly patients. It occurs most frequently in the head and neck region. Diagnosis is based on typical histological presentation on hematoxylin and eosin (H and E) stained slides together with the results of immunohistochemistry. Histologically, MCC has been classified into three distinct subtypes: Trabecular, intermediate and small cell type.

No MeSH data available.


Related in: MedlinePlus