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M Kasper

Publications and source records attributed to M Kasper.

At least 145 records · Page 8Linked to original sources
PubMed1992

Patterns of cytokeratins and vimentin in guinea pig and mouse eye tissue: evidence for regional variations in intermediate filament expression in limbal epithelium.

The anatomical distribution of different individual cytokeratin polypeptides and of vimentin was investigated by means of immunofluorescence with 41 monoclonal antibodies in guinea pig and mouse eyes. Simple epithelial type cytokeratins 7, 8, 18, and 19 selectively decorated conjunctival goblet cell clusters in mouse specimens and a continuous superficial cell layer of the corresponding part of guinea pig conjunctiva. A changed pattern of squamous epithelial type cytokeratins was found in the limbal region of the guinea pig eye as compared to the corneal epithelium. Cytokertains 3 and 17, which stained the entire corneal epithelium, were not detected, whereas cytokeratin 4, 5 and 13 were expressed. A focal vimentin and cytokeratin coexpression in the limbus of guinea pig is interpreted as indicating corneal stem cells. Similar patterns of expressions were found in the mouse ocular surface. In both species, a cytokeratin 4 staining of basal conjunctival epithelial cells could be detected. The neuroectodermally derived epithelia of the eye such as the retinal pigment epithelium and the ciliary body epithelia expressed solely the cytokeratin pair 8/18.

Animals↗
PubMed1992

Cytokeratin pattern of clinically intact and pathologically changed oral mucosa.

The various cytokeratin polypeptides in oral epithelia are expressed in dependence on site and formation of a stratum corneum. Certain cytokeratins occur permanently and others occasionally. In fibrous hyperplasia and Lichen ruber planus, patterns of cytokeratins did not deviate significantly from normal. In some but not all cases of squamous cell carcinoma and leukoplakia studied, marked aberrations of pattern were characterized by (i) appearance of cytokeratin No. 19, (ii) somewhat more frequent occurrence of cytokeratins Nos. 8 and 18, (iii) proteolytic modifications of cytokeratins, and (iv) partial loss of a few site-specific cytokeratins. The aberrations may be taken as additional diagnostic criteria for differentiation between non-aggressive and potentially aggressive leukoplakic lesion, even if they are not correlated with the conventional histological grading of dysplasia.

Adolescent↗
PubMed1992

[Immunohistochemical studies of intermediate filament type in the human hypophysis and in adenoma].

The paper describes the value of immunohistologically estimated differences in the intermediate filament protein composition of the different cell types of human adenohypophysis and the corresponding pituitary adenomas. Interestingly, some tumors failed to express any type of intermediate filament proteins, whereas other coexpress cytokeratins and vimentin/or neurofilament protein.

Adenoma↗
PubMed1991

Cytological detection of epithelial dysplasia in the oral mucosa using Feulgen-DNA-image cytometry.

Cytological scrape material of the oral mucosa from 114 patients with epithelial dysplasia and with oral cancer was stained with the Feulgen-reaction and investigated with an image analyzer. The size and the integrated optical density of cell nuclei, and four chromatin texture features were measured. All tumor slides contained cell nuclei with DNA greater than 5c, 16% of the slides had cell nuclei with DNA greater than 8c. A total of 14.5% of the tumor patients showed significantly increased DNA values in nuclei distant from the tumor. Two smears with severe epithelial dysplasia showed nuclei with DNA greater than 5c both in the tumor material and far from the tumor. Texture analysis allowed discrimination between benign, dysplastic and malignant smears. No correlation was found between DNA content and tumor staging. Image cytometry was a reliable method for detecting tumor cells. Epithelial dysplasia in areas distant from the tumor is probably due to "field canceration" of the epithelium.

Carcinoma, Squamous Cell↗
PubMed1991

Heterogeneity in the immunolocalization of cytokeratin specific monoclonal antibodies in the rat eye: evaluation of unusual epithelial tissue entities.

The immunocytochemical localization of cytokeratin and vimentin in rat eye tissues was investigated using a panel of 39 monoclonal antibodies specific for single or multiple of cytokeratin polypeptides and one polyclonal anti CK20 antiserum. The retinal and the ciliary body pigment epithelial only expressed cytokeratins 8 and 18, whereas the fetal retinal pigment epithelium and focally the adult epithelium, in the transition zone of retina and ciliary body, exhibited a reactivity for cytokeratin 19. In contrast, the non-pigmented ciliary epithelium was positive for vimentin only. In the rat conjunctiva distributed goblet cell clusters were selectively stained with cytokeratin 7, 8, 18 and 19 specific monoclonal antibodies. Among them a group of cytokeratin 8 and 18 specific monoclonal antibodies which stained the goblet cells as well as cytokeratin 8 and 18 positive internal controls did not react with either the cytokeratin 8 and 18 positive neuroectodermal cells of the rat eye nor the rat choroid plexus epithelium. This indicates differences in the phenotype e.g. conformational epitope changes, of neuroectodermal derived and other cytokeratins. The corneal and conjunctival epithelium showed a more complex distribution of squamous epithelium type cytokeratins. The limbal region as a transient zone connecting both epithelia exhibited a changing cytokeratin pattern. In general, the study emphasized the necessity to work with an enlarged antibody panel to avoid misleading results in the immunolocalization of cytokeratins.

Animals↗
PubMed1991

Changes in the distribution of intermediate filament proteins and collagen IV in fetal and adult human pancreas. I. Localization of cytokeratin polypeptides.

The expression patterns of individual cytokeratin polypeptides in foetal and adult human pancreatic tissues were examined using monoclonal antibodies. We demonstrated that human pancreatic epithelia in early stages of development (14 weeks of gestation) contain cytokeratins 7, 8, 18 and 19, which are typical of simple epithelia, as well as cytokeratin 4 and 17, which are characteristic of stratified epithelia. In the pancreatic ducts, most of these cytokeratins appeared to be expressed together. Cytokeratins 1, 5, 10, 13, 16 and 20 were not detectable. In contrast, the pancreatic parenchyma was only positive for cytokeratins 8 and 18, except a transient expression of cytokeratins 7 and 19 in pancreatic islets and acinar cells during the foetal development. A focal cytokeratin 7 staining of single acinar cells was seen in newborn and in adult islets. In the stromal tissue, vascular smooth muscle cells were partly reactive with cytokeratin 8 and 18 specific antibodies. The results are discussed in the light of differentiation-dependent changes in the expression of individual cytokeratin polypeptides in developing epithelia.

Cell Differentiation↗
PubMed1991

Expression of cytokeratin 7 in human glandular epithelium of fetal stomach.

Previously we reported the neo-expression of cytokeratin 7 in metaplastic and dysplastic stomach mucosa. In this study using immunohistochemistry and immunoblotting technique, we observed an cytokeratin 7 expression in the fetal and "infantile" human stomach, thus indicating an "oncofetal" behaviour of some simple epithelial type cytokeratins.

Fetus↗
PubMed1991

Detection of cancer metastases in regional lymph nodes: comparative histological and immunohistological investigations with the broad-range anticytokeratin monoclonal antibody A45-B/B3.

A total of 113 patients with carcinomas of breast, testis, stomach and colon were examined for lymph node metastases by means of an exact case-by-case comparison by conventional histology and by immunohistochemistry using the anticytokeratin monoclonal antibody A45-B/B3. Among 891 examined lymph nodes, 90% of metastases were recognized by both methods, about 2% by histology alone, and more than 10% by immunohistochemistry alone. The method can be applied for intraoperative frozen section diagnosis.

Breast Neoplasms↗
PubMed1991

[Prospective immunohistologic search for metastases using monoclonal anti-cytokeratin antibodies in gynecologic malignancies].

A higher prevalence of positive lymph node metastases can be found with immunohistological methods in comparison with conventional technique. We examined the lymph nodes from 20 patients with gynecological malignant tumors. We found in 304 lymph nodes with conventional technique 3.3% metastases. With immunohistological methods we showed in 9.9% of the lymph nodes metastases.

Antibodies, Monoclonal↗
PubMed1991

Cytokeratin expression in human spinal meninges and ependymal cells.

The expression of intermediate filament protein in human spinal cord arachnoid cells and ependyma was studied by immunohistochemistry and immunoblotting. Monoclonal antibodies specific for individual cytokeratin polypeptides indicated a developmental change in the presence of cytokeratin 8 and 18 in spinal leptomeninx and tanycytes of the spinal cord ependyma. While in fetal material cytokeratin 8 and 18 were abundant in arachnoid cells, in adults immunoreactivity was restricted to a few cells. Immunoblots prepared from adult as well as fetal arachnoid membranes showed significant amounts of cytokeratin 8. These findings indicate that although cytokeratin is represented in both fetal and adult arachnoid cells there is development regulation of its specific localization.

Adult↗
PubMed1991

Immunohistochemical studies on human pituitary gland and adenomas.

To study coexpression patterns in normal and adenomatous pituitaries, frozen (n = 4) and paraffin-embedded (n = 10), normal human glands and 34 pituitary adenomas were investigated, using immunoperoxidase and double-labeling immunofluorescence methods. Broad range monoclonal antibodies (mAB) against cytokeratins (CK) (lu-5, A45-B/B3, AE1/3, CAM 5.2) as well as anti-CK18 (DC10) and anti CK19 (A53-B/A2) were compared with mAB's against vimentin, epithelial membrane antigen (EMA), epithelial sialomucin (ESM 140 C1), GFAP (GF-2), neurofilament (2F11), Leu-7 (HNK-1) and polyclonal AB's against pituitary hormones (ACTH, FSH, LH, TSH, GH, PRL). CK and vimentin coexpressing endocrine cells, mainly of the ACTH type, were observed in the pars intermedia in 5 of 14 normal pituitaries. All hormone producing cells expressed CK. The mAB A53-B/A2 (CK19) stained selectively the folliculo-stellate cells in frozen and paraffin sections. EMA, sialomucin and Leu-7 antigen localized to different structures of normal pituitaries. 25 of 34 pituitary adenomas exhibited CK positive tumor cells. Coexpression of vimentin or neurofilament protein was rare (2 cases of each). 9 CK negative adenomas were also negative for other intermediate filament proteins. 6 hormone producing adenomas showed unusual positivity for CK19. Whereas EMA and sialomucin reactivity disappeared in adenoma tissues, an enhanced Leu-7 antigen expression in the GH and prolactin adenoma group was noted. The heterogeneity of antigen expression seen in normal and neoplastic pituitary cells calls for further functional studies and usage of a broad range of mAB's against intermediate filaments in immunohistochemical studies of the pituitary.

Adenoma↗
PubMed1990

Oral glutamine accelerates healing of the small intestine and improves outcome after whole abdominal radiation.

The healing effects of glutamine given orally for 8 days as a single amino acid nutrient after treatment with whole abdominal radiation (10 Gy) were studied. Rats received isonitrogenous and isovolumic diets containing 3% glutamine or 3% glycine. Control rats were not irradiated but were given identical diets. In irradiated animals, survival was 100% in animals receiving glutamine compared with 45% in animals receiving glycine. Glutamine ingestion diminished bloody diarrhea and the incidence of bowel perforation. Arterial glutamine level was higher in animals receiving glutamine in the diet, as were gut glutamine extraction (35% +/- 8% vs 12% +/- 7%) and intestinal glutaminase activity. These metabolic improvements were associated with a marked increase in villous height, villous number, and the number of mitoses per crypt in rats receiving glutamine. Glutamine was not beneficial in control nonirradiated animals. The data demonstrated that provision of oral glutamine after abdominal radiation supported gut glutamine metabolism, improved mucosal morphometrics, and decreased the morbidity and mortality associated with this abdominal radiation model.

Administration, Oral↗
PubMed1990

The expression of vimentin in epithelial cells from human nasal mucosa.

The results of an immunohistological study of the normal human nasal mucosa show that there are frequently vimentin-positive cells detectable in addition to cytokeratins in the respiratory epithelium. The vimentin cells are probably ciliated and/or goblet type in origin. Furthermore, some co-expressing cells were found in basal parts of the submucous glands.

Adult↗
PubMed1990

Absence of type IV collagen in the centre of the corneal epithelial basement membrane.

Type IV collagen is the basic structural component of all basement membranes (BM), and forms the backbone to which other BM components attach. We have found that in the centre of the adult human cornea the epithelium does not display a type IV collagen immunoreactive BM. In fetal corneas (14 and 22 weeks of gestation), however, the epithelial BM shows uninterrupted type IV collagen immunoreactivity. In similar experiments laminin immunoreactivity was observed in the entire corneal epithelial BM, in fetal as well as adult corneas. Ultrastructurally, a normal BM with a lamina lucida and a lamina densa can be observed in the conjunctiva. The adult corneal centre, however, shows epithelium without a lamina densa. Focal deposits of electron-dense material are observed in conjunction with hemidesmosomes and anchoring fibres. These observations indicate that in the development of the eye, the cornea is initially covered with an epithelium which attaches to a normal BM. Later on, however, the BM type IV collagen disappears from the corneal centre. Assuming that highly differentiated epithelium cannot produce a BM, this could be due to the high level of differentiation of central corneal epithelium, which is generated in the limbal proliferation zone. Alternatively, the acellular Bowman's layer might lack triggers to induce type IV collagen production by the epithelial cells.

Adult↗
PubMed1990

Detection of GFAP in vertebral fibrocartilage in human fetal and newborn tissue.

Previously we reported the coexpression of cytokeratin and vimentin in nucleus pulposus cells in fetal life and childhood (Stosiek et al. 1988). In this study, we observed also an unexpected reaction of an antibody against glial fibrillary acidic protein (GFAP) with some chondroblasts in fibrous cartilage, which will here be published using an enlarged panel of mono- and polyclonal antibodies specific for GFAP.

Antibodies, Monoclonal↗
PubMed1990

Expression of cytokeratins 8 and 18 in human Sertoli cells of immature and atrophic seminiferous tubules.

Tissues of human testes, either normal (23 specimens of various developmental stages), or affected by pathological conditions (19 specimens of dystopia, atrophia and/or oligospermia) were immunohistochemically examined for the expression of different cytokeratins, using mainly frozen material. Cytokeratins 8 and 18 were found in varying amounts in Sertoli cells of fetal, prepubertal and senile testes and in all cases of pathological alteration. Cytokeratins were completely absent only in normal, mature seminiferous tubules. Therefore, the immunohistochemical detection of cytokeratins in Sertoli cells seems to provide a sensitive marker for immature or damaged testes.

Adolescent↗
PubMed1990

Expression of cytokeratin 19 during human liver organogenesis.

Immunohistochemistry with monoclonal anti-cytokeratin antibodies has revealed the presence of cytokeratin 19 in embryonic and early fetal hepatocytes. With the differentiation of bile ducts at about the 10th week, cytokeratin 19 disappears from liver cells but remains in bile duct cells. This marks an important step in the organogenesis of the liver.

Antibodies, Monoclonal↗