Search results for "keratin"
showing 10 items of 303 documents
Uptake and presentation of exogenous antigen and presentation of endogenously produced antigen by skin dendritic cells represent equivalent pathways …
2008
Gene gun-mediated biolistic DNA vaccination with beta-galactosidase (betaGal)-encoding plasmid vectors efficiently modulated antigen-induced immune responses in an animal model of type I allergy, including the inhibition of immunoglobulin E (IgE) production. Here we show that CD4(+) as well as CD8(+) T cells from mice biolistically transfected with a plasmid encoding betaGal under the control of the fascin promoter (pFascin-betaGal) are capable of inhibiting betaGal-specific IgE production after adoptive transfer into naïve recipients. Moreover, suppression of IgE production was dependent on interferon (IFN)-gamma. To analyse the modalities of activation of CD4(+) and CD8(+) T cells regardi…
The human gene encoding cytokeratin 20 and its expression during fetal development and in gastrointestinal carcinomas
1993
The differentiation of the predominant cell types of the mucosal epithelium of the mammalian gastrointestinal tract is characterized by increasing amounts of an intermediate-sized filament (IF) protein designated cytokeratin (CK) 20 which is a major cellular protein of mature enterocytes and goblet cells. Here we report the isolation of the human gene encoding CK 20, its complete nucleotide sequence and the amino acid sequence deduced therefrom that identifies this polypeptide (mol. wt. 48553) as a member of the type I-CK subfamily. Remarkable, however, is the comparably great sequence divergence of CK 20 from all other known type I-CKs, with only 58% identical amino acids in the conserved …
Type I keratin cDNAs from the rainbow trout: independent radiation of keratins in fish
2002
Five different type I keratins from a teleost fish, the rainbow trout Oncorhynchus mykiss, have been sequenced by cDNA cloning and identified at the protein level by peptide mass mapping using MALDI-MS. This showed that the entire range of type I keratins detected biochemically in this fish has now been sequenced. Three of the keratins are expressed in the epidermis (subtype Ie), whereas the other two occur in simple epithelia and mesenchymal cells (subtype Is). Among the Is keratins is an ortholog of human K18; the second Is polypeptide is clearly distinct from K18. We raised a new monoclonal antibody (F1F2, subclass IgG1) that specifically recognizes trout Is keratins, with negative react…
Different patterns of cytokeratin expression in the normal epithelia of the upper respiratory tract
1985
The distribution and type of cytokeratins present in the normal human epithelia of the nasopharynx, oropharynx, tongue, palatine tonsil, epiglottis, vocal cord, and laryngeal ventricle were studied using immunohistochemical techniques and by gel electrophoresis of cytoskeletal proteins microdissected from frozen tissues. Noncornifying stratified epithelia covering the oropharynx, tongue, surface of the palatine tonsil, pharyngeal surface of the epiglottis, and vocal cord were all found to contain cytokeratins nos. 4, 5, 6, 13, 14, and 15, together with minor amounts of cytokeratin no. 19, i.e., a pattern similar to that previously reported for esophageal epithelium. The immunohistochemical …
Expression of cytokeratin 17 mRNA in oral squamous cell carcinoma cells obtained by brush biopsy: preliminary results.
2009
Background: The aim of this study was to determine the detection of cytokeratin (CK) mRNA in oral squamous cell carcinoma (OSCC) cells and to evaluate the CK relevance for OSCC diagnosis in a brush biopsy test. Methods: Fifty-two pairs of OSCC cells and normal oral mucosal cells were obtained by brush biopsy from OSCC patients. mRNA was extracted from cell pellets for real-time quantitative reverse transcriptase polymerase chain reaction (RT-qPCR). The over-expression levels of CK 17, CK 19 and CK 20 mRNA in OSCC cells were examined by SYBR green real-time RT-qPCR. Results: Compared to normal mucosal cells, the over-expression of CK 17 mRNA was detectable in 40 OSCC cells (76.9%), that o…
Interclonal heterogeneity in a human epithelioid-sarcoma cell line (Gru-1)
1994
Three clonal sub-populations, GRU-IA, GRU-IB, and GRU-IC, isolated from the human epithelioid sarcoma cell line GRU-I, were characterized morphologically, cytogenetically and with regard to proliferation kinetics. Immunocytochemically, major differences became evident in the expression of cytokeratin 18 and neurofilament proteins, which are indicative for epithelial and neural differentiation respectively. Vimentin, a mesenchymal differentiation marker, however, could be detected in all tumor cells of each sub-population. Laminin, a major compound of basement membranes, formed abundant intercellular network-like patterns in GRU-IB and GRU-IC, whereas GRU-IA was characterized by a diffuse in…
Cytoskeletal differences between human neuroendocrine tumors: A cytoskeletal protein of molecular weight 46,000 distinguishes cutaneous from pulmonar…
1985
The cytoskeletons of various human neuroendocrine (NE) tumors were analyzed immunohistochemically using antibodies against intermediate-filament (IF) proteins as well as by two-dimensional gel electrophoresis of proteins from microdissected tissue samples. All of the tumors studied were found to contain cytokeratin filaments and are therefore referred to as 'NE tumors of the epithelial type'. In addition, neurofilaments were found in most cutaneous and some pulmonary NE tumors, as well as in medullary carcinomas of the thyroid and in pancreatic islet cell tumors. The neurofilament staining was frequently concentrated in cytoplasmic IF aggregates. Gel-electrophoretic analyses showed that all…
A new cell line (8701-BC) from primary ductal infiltrating carcinoma of human breast
1989
A cell line, designated 8701-BC, was established in culture from tissue fragments of primary ductal infiltrating carcinoma of human breast. The cell cultures after the sixth passage were devoid of contaminating fibroblasts as judged by the positive staining of all cells with the specific epithelial cell markers carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA) and cytokeratin 8. The epithelial nature of these cells was confirmed by ultrastructural analyses which demonstrated the retention of specific structural properties characteristic of the original tumour. The cells possessed an abnormal karyotype with 55-60 chromosomes per cell with numerous rearrangements. They do not e…
Identification of Merkel cells in human skin by specific cytokeratin antibodies:
1984
Merkel cells are special neurosecretory cells which, in adult human skin, are usually very scarce. By immunofluorescence microscopy using antibodies to human cytokeratin polypeptide no. 18, we localized distinct non-keratinocyte cells in the glandular ridges of human fetal and adult plantar epidermis. Using electron and immunofluorescence microscopy, these cells were identified as Merkel cells containing typical neurosecretory granules as well as bundles of intermediate-sized filaments and desmosomes. Two-dimensional gel electrophoresis of the cytoskeletal fractions of microdissected epidermal preparations highly enriched in Merkel cells indicated the presence of cytokeratin polypeptides no…
cDNA sequences of the authentic keratins 8 and 18 in zebrafish
2003
From the zebrafish Danio rerio, we have cDNA cloned and sequenced a novel type II and a novel type I keratin, termed DreK8 and DreK18, respectively. We identified DreK8/18 as the true orthologs of the human keratin pair K8/18 as follows: (i) MALDI-MS assignment to the biochemically identified K8 and K18 candidates that are co-expressed in simple epithelia and absent in epidermal keratinocytes; (ii) multiple sequence alignments and phylogenetic tree analysis, showing that DreK8, within the phylogenetic tree of type II keratins, forms a highly bootstrap-supported branch together with K8 from goldfish and rainbow trout, whereas DreK18, within the phylogenetic tree of type I keratins, groups wi…