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T F Orntoft

Publications and source records attributed to T F Orntoft.

82 records · Page 5Linked to original sources
PubMed1988

Dual-parameter flow cytometry of transitional cell carcinomas. Quantitation of DNA content and binding of carbohydrate ligands in cellular subpopulations.

Quantitative DNA measurements and estimates of blood group-related carbohydrate antigen expression have been used as predictive parameters in transitional cell carcinomas (Ca). To obtain an accurate quantitative characterization of cellular subpopulations on the basis of these parameters, the authors developed a dual-parameter flow cytometric method using a fluorescence-activated cell sorter. With this method single-cell suspensions from 26 transitional cell carcinomas were analyzed by means of propidium iodide (red fluorescence) as DNA ligand, and peanut agglutinin (PNA), wheat germ agglutinin (WGA), and anti-blood group A antibody (aBGA) as carbohydrate ligands. The latter ligands were visualized directly or indirectly by FITC (green fluorescence). The carbohydrate ligand binding was correlated to the DNA content of cell populations in the way that aneuploid populations showed a higher PNA binding (P less than 0.0002) and a lower WGA (P less than 0.01) and aBGA (P less than 0.04) binding than did diploid cell populations. The binding of PNA to aneuploid populations could be further increased (P less than 0.004) by neuraminidase treatments. Thus, aneuploid cells express both neuraminic acid substituted and unsubstituted PNA receptors. The carbohydrate ligand binding was cell cycle-dependent, as it was reduced (less than 0.008) in the G2-M phase. A low WGA (P less than 0.004) or aBGA (P less than 0.02) binding was correlated to tissue invasion. Immunohistochemistry with the carbohydrate ligands showed a good correlation between aBGA (P less than 0.0005) and PNA (P less than 0.004) binding to tumor cells and flow cytometric assay of these, as well as a correlation (P less than 0.003) between cellular location of WGA receptors and flow cytometric assay of these. It seems that dual-parameter flow cytometry represents an important tool in the characterization of bladder tumors.

Carcinoma, Transitional Cell↗
PubMed1988

Immunohistochemical demonstration of estrogen receptors (ER) in formalin-fixed, paraffin-embedded human breast cancer tissue by use of a monoclonal antibody to ER.

We describe an immunohistochemical method using a monoclonal antibody to localize estrogen receptors (ER) in formalin-fixed, paraffin-embedded tissue. The avidin-biotin-peroxidase complex method was used, preceded by trypsin treatment to expose antigenic sites. In 111 breast cancer specimens studied simultaneously by a dextran-coated charcoal (DCC) assay and the paraffin section method, agreement on receptor status was found in 101 (91%) specimens. Quantitative staining features showed a high degree of correlation with the results of the steroid binding assay (r = 0.81). Studies on the influence of fixation on ER localization done in rabbit uteri showed that fixatives mainly composed of coagulating reagents (Carnoy's, Zenker's, Bouin's, Lilly's AAF, Helly's, ethanol) precluded ER staining, whereas cross-linking fixatives (formaldehyde, glutaraldehyde) preserved antigenic sites, although the immunoreactivity of the receptor was somewhat decreased. Studies on the effect of enzyme preincubation showed this to increase antigenic expression of ER in formaldehyde-fixed breast tumors and in formaldehyde-, glutaraldehyde-, and Zamboni-fixed rabbit uteri.

Animals↗
PubMed1988

Blood group ABO and Lewis antigens in bladder tumors: correlation between glycosyltransferase activity and antigen expression.

Pronounced changes in the expression of ABO and Lewis antigens have been observed in transitional cell carcinomas compared with normal urothelium. These changes are associated with changes in the activity of blood-group gene-encoded glycosyltransferases. This paper describes the correlation between blood-group antigen expression and the activity of glycosyltransferases in transitional cell carcinomas. Examined individuals were A1A2BO, Lewis, and secretor typed by the use of blood and saliva. The activity of alpha-2-, and alpha-4-L-fucosyltransferases as well as the alpha-3-N-acetyl-D-galactosaminyltransferase were determined as p-moles of labelled sugar incorporated by Lacto-N-biose I and 2'-fucosyllactose, respectively, per 100,000 carcinoma cells. In 3 non-secretors whose erythrocytes types as Le(a+b-), the alpha-2-L-fucosyltransferase activity was similar to that in 3 secretors, and the Leb antigen could be demonstrated to be present by monoclonal antibodies, both by immunohistological and immunochemical means. In 11 tumors from A individuals, the A1-transferase was severely reduced in 9 individuals who showed a loss of A antigen expression, and present in 2 individuals with A antigen expression in cytoplasmic vesicles. In conclusion, we demonstrate a good correlation between individual glycosyltransferase activity and expression of blood group Leb and loss of expression of blood group A in transitional cell carcinomas. Immunostaining of neutral glycolipids separated by TLC showed the Leb-active glycolipids to be simple hexa-saccharides in both secretors and non-secretors.

ABO Blood-Group System↗
PubMed1988

Blood group ABO-related antigens in fetal and normal adult bladder urothelium. Immunohistochemical study of type 2 chain structures with a panel of mouse monoclonal antibodies.

Seven monoclonal antibodies with specificity for blood group antigens carried by type 2 chain core structures (N-acetyllactosamine, H, Le(x), LeY, A monofucosylated, A difucosylated (AleY), A type 3) were used to study the distribution of these antigens in normal human bladder urothelium. The urothelial samples were from 7 fetuses (aged 7 to 21 weeks), and 22 adults. By means of an immunohistochemical method applied to frozen and fixed tissues, localization of antigens in the 3 cell layers of urothelium was compared with individual ABO, Lewis, and Secretor type. During fetal development, N-acetyllactosamine, H, and LeY antigens were continuously expressed, whereas Le(x) varied with age. The A type 3 chain was present in fetal urothelium but A type 2 chain was not. In adults, we observed a unique blood group distribution: with complex antigens like LeY and ALeY in all cell layers, and a unique expression of most of the less complex antigens in the luminal cell layer. Pretreatment of tissue sections with neuraminidase proved that Le(x) and N-acetyllactosamine could be partly substituted by sialic acid A type 3 chain and most of N-acetyllactosamine antigens were present only in cytoplasm, whereas all other examined antigens could be present both in cytoplasm and on cell membranes. Blood group A antigen expression was related to erythrocyte A1 and A2 subtype, and a remarkable correlation was found between type 1 chain related secretor status and expression of Le(x), LeY, and A antigens.

ABO Blood-Group System↗
PubMed1987

Blood group ABO and Lewis antigen expression during neoplastic progression of human urothelium. Immunohistochemical study of type 1 chain structures.

The deletion of blood group ABO antigen expression in bladder carcinoma has attracted attention because of its potential as a prognostic parameter. Based on recently produced monoclonal antibodies against blood group antigens, it has become possible to elucidate the carcinoma-associated modulation of these antigens at a molecular level. In this study we have used a panel of monoclonal antibodies (H, Lea, Leb, A, ALeb) that are specific to type 1 chain structures. By the use of an immunohistochemical method, the histologic and cytologic location of these antigens in the urothelium was studied in 25 biopsies from transitional cell carcinomas and compared to 21 previously examined normal biopsies. Urothelial blood group reactivity was compared to Lewis and secretor status. The authors found a series of events associated with neoplastic progression of noninvasive urothelium: a disruption of the orderly stratification of blood group antigens in different cell layers; cytostructural relocation of cytoplasmic antigens to the cell surface; loss of correlation between urothelial blood group antigens and secretor status; and gradual deletion of antigens. In the invasive tissue these events were followed by a total deletion of A and H isoantigens and uniform expression of Lewis b and sialyted Lewis a antigen. These findings indicate that there is a complex modulation of blood group antigen biosynthesis associated with the neoplastic progression of the human urothelium.

ABO Blood-Group System↗
PubMed1987

Blood group ABO and Lewis antigens in fetal and normal adult bladder urothelium: immunohistochemical study of type 1 chain structures.

Five monoclonal antibodies specific for structural variants of type 1 chain blood group antigens (H, Lea, Leb, A, ALeb) were used to study the distribution of these particular antigens in normal bladder urothelium. The urothelium samples were taken from seven human fetuses (aged seven to 21 weeks) and 19 adults. The adults were blood group A and O individuals, and their antigen expression was compared to ABO, secretor, and erythrocyte Lewis status. Detailed data on the histological location of the antigens were obtained by means of immunohistochemical methods. In fetuses expression of Lewis a and A antigens was stage-dependent, whereas the Lewis b and H antigens were consistently present at all stages. In adults the urothelial blood group antigen expression seemed to be correlated to ABO and secretor status, but not to erythrocyte Lewis type. Secretors expressed primarily ABO isoantigens on their cell membranes, whereas non-secretors (four individuals) expressed inappropriate Lewis antigens. Examination of the histological distribution of the antigens showed results different from earlier examined epithelia. In adult bladder urothelium from A secretors, only the most complex antigens (Leb, A, ALeb) were present in the basal germinative cell layer, whereas the luminal umbrella cell layer expressed both these antigens and showed a unique expression of less complex precursor antigens (H, Lea), as well as sialylated Lewis a antigens.

ABO Blood-Group System↗
PubMed1987

Gynecomastia. Immunohistochemical demonstration of estrogen receptors.

Immunohistochemical estrogen receptor (ER) analysis using a monoclonal ER antibody was performed on a total of 30 specimens from 26 patients with gynecomastia. Twenty-six specimens were ER-positive, 3 were ER-negative, and the analysis failed in one case. Immunohistochemical analysis proved more sensitive than biochemical ER analysis in a group of 20 patients, and in a group of 6 patients, the immunohistochemical analysis correlated well with in vitro hormonal sensitivity of the gynecomastic tissue. Semi-quantified ER content was inversely correlated with patient age. There was no relationship between ER content and either histopathologic features or hormonal status. In conclusion, this study demonstrates that the intracellular ER responsible for estrogenic stimulation is present in most gynecomastic tissue specimens, supporting the general assumption that estrogen can be one of the hormones responsible for the development of gynecomastia.

Adult↗
PubMed1985

Comparative immunoperoxidase demonstration of T-antigens in human colorectal carcinomas and morphologically abnormal mucosa.

The T-antigen (Thomsen-Friedenreich antigen) is a well-characterized tumor-associated glycoprotein that is immunologically reactive in humans. In order to demonstrate the presence of T-antigens in colorectal tissue, benign and malignant tissue from 46 patients with colorectal cancer were examined by means of an immunoperoxidase method. Peanut agglutinin and a polyclonal immune rabbit antiserum were used to demonstrate T-antigens on 72% of formalin-fixed malignant specimens and on more than 92% of frozen malignant specimens. Both ligands bound to the cell membrane and secreted mucus, but only the rabbit serum showed routine staining of the cytoplasm. The T-antigen distribution was heterogeneous without relation to degree of differentiation. Transitional mucosa adjacent to malignant tissue showed a strong anti-T binding to secreted mucus. Slightly morphologically altered crypts remote from the carcinoma expressed T-antigens. Unexpectedly, both ligands bound to nerve cells of the enteric ganglia. These contain gangliosides with immunodominant oligosaccharides identical with those on the T-antigen. Therefore, cross-reactions might have occurred between the gangliosides and the used ligands. The T-antigens now seem to be present in various widespread cancers, and they probably occur early in malignant transformation.

Antibodies↗
PubMed1984

A method for T-antigen demonstration by a polyclonal antibody and peanut lectin; elimination of cross-reaction with naturally occurring antibodies.

Antisera and a lectin were used to demonstrate T-antigens in colorectal carcinomas. Rabbits were immunized with red blood cells on which the T-antigen had been exposed. The obtained polyclonal antiserum and a crude lectin (PNA) prepared from peanuts were used in an immunoperoxidase technique. The crude lectin and a chromatographic pure lectin showed the same staining specificity. Different fixatives, length of fixation and buffer compositions were tested on paraplast and frozen sections. Four per cent formaldehyde preserved the antigens well in paraplast embedded tissues when fixation was shorter than 48 h. In the immunoperoxidase technique the chromatogen used was 3-amino-9-ethyl-carbazole whose staining intensity was sensitive to the H2O2 concentration. Agglutination of T-exposed red blood cells was used to assess the anti-T titre of various sera. Normal animal serum contained anti-T antibodies, and the possibility of false positive reactions and methods to avoid it in immunohistochemistry is discussed.

Adenocarcinoma↗