Search results for "Histochemistry"

Patterns of cytokeratin and vimentin expression in the human eye

1988

We studied the expression of the various cytokeratin (CK) polypeptides and vimentin in tissues of the human eye by applying immunocytochemical procedures using a panel of monoclonal antibodies as well as by performing biochemical analyses of microdissected tissues. Adult corneal epithelium was found to contain significant amounts of the cornea-specific CKs nos. 3 and 12 as well as CK no. 5, and several additional minor CK components. Among these last CKs, no. 19 was found to exhibit an irregular mosaic-like staining pattern in the peripheral zone of the corneal epithelium, while having a predominantly basal distribution in the limbal epithelium. Both the fetal corneal epithelium and the con…

Psammomatous malignant melanoma arising in an intradermal naevus

2001

Psammomatous malignant melanoma arising in an intradermal naevus Aims: A wide variety of differentiation patterns may be found in malignant melanoma. Schwannian features are unusual, and mostly present in the desmoplastic variant. We report the first description of psammoma bodies in malignant melanoma. Methods and results: A malignant melanoma arose in an intradermal naevus of the scalp in a 51-year-old woman, displaying focal neural-like features in the form of rosette-like pseudo-meissnerian alveolar nests, as well as numerous psammoma bodies grouped in a few areas. Tumour cell immunostaining for S100, HMB45, NKI-C3, and vimentin was detected. In addition, both malignant and benign melan…

Cutaneous sclerosing Pacinian-like perineurioma

2001

Cutaneous sclerosing Pacinian-like perineurioma Aims: The term perineurioma has been used to designate a variety of clinically and histologically different proliferations of perineurial cells based on immunohistochemical and/or ultrastructural characterization. There are two different groups of neoplasms derived from perineurial cells: extraneural or soft tissue perineuriomas, and intraneural perineuriomas. Recently, a sclerosing variant of cutaneous perineurioma has been described. Methods and results: We report a case of a cutaneous form of perineurioma, combining features of the intraneural and sclerosing varieties, as well as showing a Pacinian pattern of growth. In order to assess the …

The histochemistry of psoriasis.

1958

Intraepidermal formation of Merkel cells in xenografts of human fetal skin.

1990

An experimental transplantation model using human fetal skin was applied to approach the question of the embryologic origin of human Merkel cells. Palmar and plantar skin from five fetuses, between 8 and 11 weeks of estimated gestational age (EGA), was xenografted to subcutaneous beds of nude mice. After 4 or 8 weeks of growth, biopsies were taken from these xenografts and examined for the presence of Merkel cells, using immunocytochemistry with antibodies specific for simple epithelial-type cytokeratins and neuron-specific enolase (NSE) as well as using electron microscopy. Skin from the same fetuses at the time of transplantation was screened in the same way. In all fetuses, no (or very s…

Diffuse large B-cell lymphoma, not otherwise specified of the palate: A case report

2013

Diffuse large B-cell lymphoma (DLBCL) is the most frequent type of non-Hodgkin´s lymphoma found in oral and maxillofacial regions. A large number of cases may be biologically heterogeneous, which are commonly defined as DLBCL, not otherwise specified (NOS) by the World Health Organization (WHO-2008). The present case reports on an ulcer of raised and irregular edges, found on the border between the hard and soft palate, as the first and only manifestation of an extranodal non-Hodgkin lymphoma in an 85-year-old patient. Incisional biopsy was carried out, and the specimen revealed a proliferation of large lymphoid cells suggestive of diffuse large cell lymphoma. An immunohistochemical analysi…

Preservation of glial cytoarchitecture from ex vivo human tumor and non-tumor cerebral cortical explants: A human model to study neurological diseases

2007

For the human brain, in vitro models that accurately represent what occurs in vivo are lacking. Organotypic models may be the closest parallel to human brain tissue outside of a live patient. However, this model has been limited primarily to rodent-derived tissue. We present an organotypic model to maintain intraoperatively collected human tumor and non-tumor explants ex vivo for a prolonged period of time (similar to 11 days) without any significant changes to the tissue cytoarchitecture as evidenced through immunohistochemistry and electron microscopy analyses. The ability to establish and reliably predict the cytoarchitectural changes that occur with time in an organotypic model of tumor…

Evaluation of polysialic acid in the diagnosis of Wilms' tumor. A comparative study on urinary tract tumors and non-neuroendocrine tumors.

1988

The polysialic acid moiety of the neural cell adhesion molecule has been shown to represent an onco-developmental antigen which can be detected in both embryonic human kidney and Wilms’ tumor but not in normal adult human kidney. In the present comparative study, Wilms’ tumors, clear cell (bone-metastasizing) sarcomas of kidney, cystic nephromas, renal cell carcinomas, transitional cell carcinomas and papillomas of the renal pelvis, ureter and urinary bladder (as well normal transitional epithelium from these regions), Ewing sarcomas, hepatoblastomas, rhabdomyosarcomas, and carcinomas of the stomach, colon, exocrine pancreas, lung, and esophagus, were investigated immunohistochemically for …

A novel monoclonal antibody to a distinct subset of cutaneous dendritic cells.

1992

A monoclonal antibody was generated by immunizing rats with Langerhans cell (LC)–enriched epidermal cells obtained from BALB/c mouse earskin after epicutaneous application of the contact sensitizer 2,4-dinitrofluorobenzene (DNFB). The antibody 4F7 detects in normal mouse skin, few dermal cells showing the morphologic, phenotypic, and functional properties of accessory dendritic cells, but lacking Birbeck granules. The capacity to stimulate allogenic T cells in the mixed leucocyte reaction resembles that of freshly isolated LCs. After DNFB application, an increased number of 4F7+ dendritic cells are found in the dermis and, in addition, some labeled dendritic cells occur in the epidermis. So…

In vitro analysis of the phenotypical and functional properties of the 4F7+ cutaneous accessory dendritic cell

1995

The monoclonal antibody 4F7 detects a molecule on dermal and epidermal Ia+ dendritic cells (DCs), and some of these cells are Birbeck granule-containing cells. Here we report on the phenotypical and functional characteristics of these cells which were highly enriched by 4F7-labelled immunomagnetic beads. The ultrastructural, immunocytochemical and cytochemical analyses of these preparations showed cells with the typical characteristics of DCs. The cells were found to express the DC marker NLDC145, but not 33D1. The C3bi receptor and marker F4/80 were only expressed by epidermal 4F7+ cells. The capacity of freshly isolated 4F7+ epidermal and dermal DCs to activate allogeneic T cells in a mix…