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Biomedical subjects

E Dabelsteen

Publications and source records attributed to E Dabelsteen.

At least 163 records · Page 9Linked to original sources

Changes in carbohydrate expression of lichen planus affected oral epithelial cell membranes.

The purpose of the present study was to examine possible epithelial cell membrane changes in lichen planus affected oral mucosa by the use of the lectins concanavalin-A and ricinus communis agglutinin fraction I. It was shown that these lectins in contrast to what was found in normal epithelium do not bind to the cell membranes of basal cells of lichen planus affected epithelium. The lack of binding of lectins suggests changes in exposed carbohydrates at the surfaces of the cells. The findings may support the hypothesis of antigenic changes in the lichen planus affected epithelium.

Cell Membrane↗

A method for studying epithelial-mesenchymal interactions in human oral mucosal lesions.

A system has been developed for examining connective tissue influence on keratinization of normal and leukoplakic human oral epithelia. Paired biopsy specimens of normal and leukoplakic mucosa were left intact or were incubated in 1 mM EDTA to permit epithelial-connective tissue separation and various recombinations of the epithelium and connective tissue. The tissues were transplanting to subdermal sites of "nude" (nu/nu) mice and were protected by polyethylene capsules. 44% of implants performed were recovered apparently vital. Preexisting structure was retained after epithelial-connective tissue separation and self-recombination. Cross-recombined specimens showed changes in patterns of keratinization including changes of keratinized leukoplakic epithelium to a non-keratinized type.

Animals↗

Demonstration of actin in the fibroblasts of healing palatal wounds.

The purpose of this study was to gain information which might be helpful in understanding the influence of palate surgery on abnormal maxillary growth. The finding of actin-rich cells in the granulation tissue of palatal wounds supports the hypothesis that one of the functions of those cells is contraction--and the latter subsequently leads to convergence of the wound margins and aberrations in growth of the underlying skeletal tissue. Much additional information is needed for final proof of that hypothesis. At present little is known about the initiation, regulation, or control of the proposed contractile phenomena, or the process of aberrent maxillary growth. Such information will be necessary for further development of clinical techniques that will allow normal maxillofacial growth after surgery on the palate at an early age.

Actins↗

Concanavalin A and ricinus communis receptor sites in normal human oral mucosa.

Fluorescein conjugates of concanavalin A (Con-A) and Ricinus communis fraction 120 (RCA120) were shown to bind to the cell surfaces of basal and spinous cell layers in oral buccal mucosa. Palatal epithelium showed distinct binding to basal and spinous cells; cell membranes in the granular layer occasionally bound Con-A and always RCA120. The ultrastructural localization of Con-A binding sites on exfoliated buccal cells was detected by the Con-A peroxidase staining method. The Con-A receptors were seen on the cell surface in association with the outer leaflet of the plasma membrane. The reaction products appeared as a homogeneous, electron-dense layer containing irregularly distributed globules.

Basement Membrane↗

Demonstration of actin in oral epithelial cells.

Two human sera with antibodies against smooth muscle were used to investigate the distribution of actin in moving oral epithelial cells by immunocytochemical methods. Epithelial outgrowths from explants of rat and human oral mucosa showed a constant positive staining in the peripheral parts of the marginal cells but not in the more central parts of the epithelial sheet. This is in agreement with theories of the importance of the marginal cells in the migratory behavior of the epithelial outgrowth. Subcultured epithelial cells from the human explants showed positive staining of fine fibers in the cytoplasm. During healing of experimental oral wounds from humans and monkeys actin fibers could be demonstrated in only one of 18 cases in the epithelial cells adjacent to the wound, though positive staining of various cells was seen in the underlying tissue. This is in contrast to the evidence presented in previous studies of cells taking part in the re-epithelialization process.

Actins↗

Serologic markers and chromosome variants in a pair of chimeric twins.

A pair of chimeric twins, T.S. (male) and M.R. (female) first examined in 1970 are reinvestigated in order to determine if the proportions of admixture of red cells in their blood are unchanged, and if erythrocytes and leukocytes show the same percentage of admixture. T.S., M.R. and their family are investigated for HLA, serum types, and erythrocyte antigens and enzymes. A quantitative determination of 'foreign' cell populations in the blood of each twin is attempted for the systems ABO, and HLA, and for sex chromosomes in PHA stimulated lymphocytes. The results for the ABO system obtained by agglutination technique and by a double-layer immunofluorescence technique indicate that the population of M.R. erythrocytes in T.S. has decreased during the 7-year period, and is now below half the size found in 1970. Erythrocytes and leukocytes show the same percentage of admixture in both twins.

ABO Blood-Group System↗

Expression of Ricinus communis receptors on epithelial cells in oral carcinomas and oral wounds.

The histological distribution of receptors for Ricinus communis Fraction 1 (RCA1) in oral carcinomas and in oral epithelial cells during wound healing has been studied by use of fluorescein-tagged RCA1. Biopsies from 15 human oral carcinomas and adjacent normal mucosa showed RCA1 receptors at the cell membranes in the basal and spinous layer of the normal epithelium, whereas receptors could not be demonstrated in invading islands of the tumors. In healing oral wounds from eight humans and three monkeys, RCA1 receptors were demonstrated both in normal epithelium adjacent to the wounds and in the epithelial outgrowth from the wound margin. Titrations, however, showed that the epithelial outgrowth reacted more weakly than did the normal adjacent epithelium. These results support previous in vitro studies showing changes in carbohydrate composition of moving normal cells and of malignant cells, a finding that may be of interest in relation to formation of metastases.

Animals↗

Intercellular and circulating antibodies in patients with dyskeratosis follicularis, Darier's disease.

Skin biopsies from 6 patients, and biopsies of the palatal mucosa of 4 of these patients with dyskeratosis follicularis (DF) (Dariers disease) were examined for in vivo bound antibodies by means of a direct immunofluorescence (IF) technique. Antibodies located in the intercellular substance of the epidermis were found in the skin lesions of all patients. Immunoglobulins of the classes IgG, IgA and IgM as well as C3 were found in all lesions. No antibodies reacting with the palatal mucosa were found. Sera from 6 patients with DF and 10 control persons were tested by an indirect IF technique for circulating antibodies. Guinea pig lip and normal oral mucosa and skin were used as antigens. All patients sera and one control serum reacted with the basal cell of the guinea pig lip. Three DF sera--but no control sera--reacted with the basal cells of human oral mucosa. None of the sera reacted with human skin.

Antibodies↗

Immunoelectrophoretic studies on pig intestinal brush border proteins.

Brush borders were prepared from pig intestinal mucosa and the membrane proteins solubilized with either Triton X-100 or papain. Proteins, thus released, were used as antigens to raise antisera in rabbits. The immunoglobulin G fractions were isolated and shown by the double layer immunofluorescence staining technique to react only with the brush border region of the enterocyte. The antibodies obtained were used in immunoelectrophoretic studies on the brush border proteins. Eight hydrolytic activities were identified by the use of histo-chemical staining methods. These were the microsomal aminopeptidase (EC 3.4.11.2), aspartate aminopeptidase (EC 3.4.11.7), dipeptidyl peptidase IV (EC 3.4.14.X), lactase (EC 3.2.1.23), glucoamylase (EC 3.2.1.3), sucrase (EC 3.2.1.48), isomaltase (EC 3.2.1.10) and alkaline phosphatase (EC 3.1.3.1). In addition, at least four faint immunoprecipitates were formed but none of these were identified.

Alkaline Phosphatase↗

Deposits of immunoglobulin G and complement C3 in recurrent aphthous ulcerations.

Deposits of immunoglobulin G (IgG) were demonstrated at the basement membrane zone in lesions from 14 out of 16 patients with recurrent aphthous ulcerations (RAU) by means of an immunofluorescent (IF) staining technique. Deposits of complement C3 were demonstrated at the same localization in lesions from 16 out of 16 patients with RAU. Similar deposits of C3 were demonstrated in 11 out of 12 experimentally produced oral wounds (EOW). Immunoglobulin deposits were not detected in the EOW. No deposits of immunoglobulin or C3 were revealed in 12 biopsies from normal oral mucosa (NOM). Further, the IF investigation demonstrated circulating autoantibodies against the cytoplasm of autologous oral epithelial cells in patients with RAU. The specificity of the present immunologic reactions and their possible role in the pathogenesis of RAU are discussed.

Adult↗

The relationship between expression of epithelial B-like blood group antigen, cell movement and cell proliferation.

Healing wounds in the oral mucosa of rhesus monkeys were examined by an immunofluorescence staining method to demonstrate the distribution of a blood group antigen cross reacting with human group B, and by labelling with tritiated thymidine to localize areas of cell proliferation. Within hours, blood group antigen reactivity was lost from epithelial cells adjacent to the wound margin. Reactivity was absent from the epithelial outgrowth into the wound, but returned with restoration of epithelial continuity. The zone of increased cell proliferation lay adjacent to, but outside of, the area of antigen loss. Antigen loss appeared to be associated with an area of increased cell movement, a finding of interest in relation to reports of antigen loss from epithelial tumors.

ABO Blood-Group System↗

Histological localization of two dipeptidases in the pig small intestine and liver, using immunofluorescence.

Antibodies were raised in rabbits against glycylleucine dipeptidase (EC 3.4.13.2) and proline dipeptidase (EC 3.4.13.9) purified from the pig. IgG fractions were isolated and purified by affinity chromatography on Sepharose (dipeptidase) columns and then used in histological studies on the small intestine and the liver from pig, using the double layer immunofluorescence-staining technique. In the small intestine the dipeptidases were predominantly localized in the cytoplasm of the enterocytes. A reaction was also seen in the leukocyte cytoplasm in the stroma of the small intestine. The dipeptidases were present in the villi but not in the crypts. In the liver the dipeptidases were localized in the cytoplasm of the hepatocyte, but strong fluorescence was also obtained in the epithelium of the bile ducts. Glycylleucine dipeptidase and proline dipeptidase have been isolated from liver tissue and they were shown to be immunologically identical with the purified intestinal dipeptidases.

Animals↗

Selective loss of blood group antigens during wound healing.

Frozen sections of healing wounds of the oral mucosa of 3 rhesus monkeys were examined by a double layer immunofluorescent technic for the presence of blood B-like antigens. Antigen activity was present in normal epithelium and in the epithelial outgrowth into the wounds but was absent from the outgrowth following treatment with lipid solvents. This finding suggests that glycoprotein but not glycolipid associated antigen is lost from the surface of epithelial cells during wound healing, a pattern of selective loss which may reflect a difference between regenerative and neoplastic lesions.

Animals↗

An improved technique in the diagnosis of pemphigus.

Pemphigus lesions are characterized by intraepithelial bullae. This phenomenon is used in a new practical procedure for obtaining specimens of diseased epithelium with a minimum of discomfort to the patient. This procedure makes it possible to demonstrate in vivo bound immunoglobulins in the epithelium without taking an ordinary biopsy for making the diagnosis of pemphigus.

Biopsy↗

Blood group antigens A and B in ameloblastomas, odontogenic keratocysts and non-keratinizing cysts.

The expression of blood group antigens A and B has been studied in 8 ameloblastomas, 16 odontogenic keratocysts from patients with basal cell nevus syndrome, 11 odontogenic keratocysts from patients without the syndrome, and 12 non-keratinizing odontogenic cysts, using a double layer immunofluorescence staining technique. The amount of antigen in the lesions was compared with the content of antigen in normal buccal mucosa from each patient. All ameloblastomas reacted negatively, three cysts from the patients with the basal cell nevus syndrome reacted negatively, and the odontogenic keratocysts from patients without the syndrome as well as the non-keratinizing odontogenic cysts all gave a positive reaction.

ABO Blood-Group System↗