China
Africa
Explore chapters and articles related to this topic
Monoclonal Antibodies Used for the Diagnosis of the Small Round Cell Tumors of Childhood
Published in John T. Kemshead, Pediatric Tumors: Immunological and Molecular Markers, 2020
J.T. Kemshead, J. Clayton, K. Patel
Intermediate filament proteins can be divided into five different groups, namely vimentin, desmin, cytokeratin, glial fibrillary acidic protein (GFAP) and neurofilaments. Within these groups subdivisions have been made. For example many different forms of cytokeratins have been identified. The precise function of intermediate filament proteins has to be elucidated, but it is thought that they play a structural role in the integrity of the cell. These proteins are composed of polymorphic subunits, and the expression of a particular intermediate filament type is restricted to a subset of tissues. In general the specific pattern of intermediate filament expression is maintained during transformation making the proteins useful as markers for malignant disease.
Epithelial Cells
Published in Bruce S. Bochner, Adhesion Molecules in Allergic Disease, 2020
A variety of proteins and glycoproteins make up the different portions of the desmosome. Membrane glycoproteins, known as desmogleins or desmocollins, project into the intercellular space to form an intercellular adhesive structure (45). Three desmogleins have been identified (48): desmoglein I has a molecular weight of 150 kD, desmoglein II is a 110–120 kD protein, and desmoglein III is considerably smaller (22 kD). Although desmoglein I is also found in the desmosomal plaque (49), the cytoplasmic side of the desmosome is primarily composed of four nonglycosylated proteins called desmoplakins. Desmoplakins I and II (250 kD and 215 kD, respectively) are somewhat larger proteins than desmoplakins III and IV (83 kD and 78 kD, respectively) (50). Desmin, vimentin, and particularly cytokeratin, make up the tonofilaments (45). Cytokeratin expression is often used as a characteristic feature of epithelial cells.
Models of Toxicity Screening Using Cultured Cells
Published in John J. Lemasters, Constance Oliver, Cell Biology of Trauma, 2020
Roberta L. Grant, Daniel Acosta
Cytokeratin is an intermediate filament of the cytoskeleton found only in epithelial cells. The presence of these filaments was demonstrated in our culture system by indirect immunofluorescence. Transmission electron microscopy revealed the presence of junctional complexes, which are also characteristic solely of epithelial cells. Scanning electron microscopy revealed the presence of endocytic pits and of apical microvilli, demonstrating that normal cell polarization is maintained in culture.
Proteomic analysis shows that the main constituent of subepidermal localised cutaneous amyloidosis is not galectin-7
Published in Amyloid, 2021
Jessica R. Chapman, Anna Liu, San S. Yi, Enmily Hernandez, Maria Stella Ritorto, Achim A. Jungbluth, Melissa Pulitzer, Ahmet Dogan
Lichen or macular localised cutaneous amyloidoses have long been described as keratinic amyloidoses and believed to be due to the deposition of cytokeratin peptides from degenerating epidermal cells [7]. The keratin gene family consists of 54 distinct functional genes, but keratin expression is dependent upon the cell type, differentiation state of the cells, and can be modulated upon damage or infection [8]. Cytokeratins are expressed in the cytoplasm of epithelial cells. Proliferative basal keratinocytes are mitotically active and express keratin 5, 14, and small amounts of 15. Upon differentiation these cells stop dividing and start expressing keratin 1 and 10 as they migrate into the suprabasal layers. Immunohistochemistry (IHC) and immunofluorescence studies have shown that keratin 5 is the predominant cytokeratin protein in amyloid deposits and keratin 14 is less commonly localised to amyloid deposits [9,10].
Intestinal permeability, microbial translocation, changes in duodenal and fecal microbiota, and their associations with alcoholic liver disease progression in humans
Published in Gut Microbes, 2020
Luca Maccioni, Bei Gao, Sophie Leclercq, Boris Pirlot, Yves Horsmans, Philippe De Timary, Isabelle Leclercq, Derrick Fouts, Bernd Schnabl, Peter Stärkel
Cytokeratin 18 is released upon cell damage (necrosis, apoptosis) and has been considered as a liver-specific cell damage marker.32 Serum CK18-M65 increased significantly in AUD patients compared to healthy volunteers. When looking at the different clinical subgroups, high CK-M65 levels were found in AUD patients with progressive ALD but not in those with non-progressive forms of the disease (Figure 2). Receiver operating curve (ROC) analysis showed that serum CK18-M65 levels allowed to distinguish with high accuracy progressive ALD from the non-progressive forms of liver disease (AUROC = 0.8767; 95%CI: 0.7983–0.9551; p < .0001). We then identified the cutoff using the Youden’s statistics (416 U/L) with the best specificity and sensitivity profile (85.7% and 77.1%, respectively). Interestingly, CK18-M65 levels did not separate patients with steato-hepatitis from those with steato-fibrosis within the progressive ALD group (Supplementary Figure 1). Thus, CK18-M65 was associated with liver damage regardless of fibrosis.
Effects of progestin-only contraceptives on the endometrium
Published in Expert Review of Clinical Pharmacology, 2020
Carlo Bastianelli, Manuela Farris, Vincenzina Bruni, Elena Rosato, Ivo Brosens, Giuseppe Benagiano
One study dealt with the effect of the sustained release of LNG on members of the cytoskeletal intermediate filament protein family [153]. Specifically, cytokeratins 8, 18 and 19 were investigated in 37 Norplant users and in 65 controls. They observed a significantly stronger staining intensity in controls, where cytokeratins were mainly located in the apical region of epithelial cells; in contradistinction to this, in implant users they were equally distributed. It seems therefore that that long-term exposure to LNG can significantly reduce cytokeratin expression in endometrial epithelial cells. Another study [154] focused on the von Willebrand factor (vWF), a glycoprotein involved in hemostasis, investigating whether changes in its expression may influence bleeding patterns. To this end, they examined biopsies from 37 Norplant users (3 to 12 months) and from 73 controls at various phases of the normal menstrual cycle. No differences were found between control and Norplant users in the localization of vWF staining, but staining intensity in the endometrium of implants bearers was significantly lower than in controls at mid cycle. On the other hand, it remained significantly higher than in the late secretory and pre-menstrual endometrium. No correlation was found between vWF staining and endometrial histology, bleeding patterns, serum estradiol or P4. However, vWF staining was positively correlated to the number of bleeding/spotting days within a 90-day reference period prior to the biopsy.