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Biomedical subjects

M Vierbuchen

Publications and source records attributed to M Vierbuchen.

At least 55 records · Page 3Linked to original sources
PubMed1986

Comparative histological, histochemical, immunohistochemical and biochemical studies on oestrogen receptors, lectin receptors, and Barr bodies in human breast cancer.

The present study performed on a total of 567 cases of human female breast cancer compares the results of the biochemical assay (dextran-coated charcoal assay = DCC) for oestrogen receptor (ER) with those of several morphological methods developed for the detection of the ER or for the prediction of prognosis by use of other systems (FSA = fluorescent ligand binding assay, ER-ICA = monoclonal antibody assay for ER, LRA = lectin receptor assay using peanut agglutinin, and Barr body estimation). Whereas no correlation at all was observed among the results of the DCC and those of the FSA and Barr body estimation, the ER-ICA and the LRA showed an unanimous tendency towards higher values of ER with increasing intensity of the staining product. The results of the ER-ICA may be expressed by an immuno-reactive score (IRS) calculated from the staining intensity (SI) and the percentage of positive cells (PP). The morphological methods are evaluated with special regard to their correlation with the DCC, their theoretical basis, and their practical application. In summary, the ER-ICA appears to be the sole method directly visualizing the ER protein and--in contrast to the DCC--is therefore completely independent of the content of endogenous or exogenous oestrogens in the tumor tissue. The LRA provides valuable additional information concerning tumour differentiation and possible response to endocrine therapy, whereas the FSA and Barr body estimation should be considered as obsolete and should therefore be abandoned.

Antibodies, Monoclonal↗
PubMed1986

Immuno- and histochemical studies on galactan and human blood group-related receptors in the bovine lung.

Using a monoclonal anti-galactan antibody and streptococcus B type II antibody, the distribution of lung galactan could be demonstrated for the first time in a vertebrate organ. In addition to the immunochemical demonstration of the bovine lung galactan, a human blood group A-like glycoprotein is detectable by lectinological methods in the bovine lung tissue. Various other lectin-receptors, for instance those of the peanut lectin (PNA) or for lectins with L-fucose (UEA) and N-acetyl-lactosamine (ECA) specificity show a typical staining pattern in bovine lung.

Amino Sugars↗
PubMed1986

Lectin-binding sites in human parathyroid tissue.

The aim of this study was to demonstrate several lectin-binding sites in human parathyroid tissue and to correlate these results with functional activity. The following lectins were tested for binding sites with certain carbohydrates (in parentheses): Arachis hypogea (PNA) (galactose), Ulex europaeus I (UEA) (fucose) and concanavalin A (ConA) (mannose). In addition to normal parathyroids used as controls (13 cases), we examined adenomas associated with a clinical picture of primary hyperparathyroidism of differing severity (31 cases), atrophic glands contralateral to a hyperfunctioning adenoma (7 cases), and secondary (renal) hyperplasia (12 cases). Use of PNA (with and without neuraminidase treatment) and UEA yielded negative staining in normal glands, a wide variety of reactions in adenomas, and frequent dense precipitates in atrophic parathyroids, whereas ConA yielded positive staining in all kinds of parathyroid tissue. Assessment of functional activity of adenomas by clinical parameters (pre-operative serum levels of calcium and parathormone) displayed a significant correlation with the semiquantitative grading of the histochemical reactions after PNA and UEA. Lectin-binding sites in parathyroid chief cells of adenomas are believed to indicate some of the cell structures or products directly involved in the secretory process, including degradation. Although ConA may recognize constituent parathyroid glycoproteins, the binding sites for PNA and UEA are thought to be partially associated with secretory glycoprotein (SP-I), as is known from animal experiments. The positive reaction of the atrophic gland may result from degradation enforced by exposure of primarily non-terminal carbohydrate components.

Adenoma↗
PubMed1984

Characterization of glycoconjugates of human gastrointestinal mucosa by lectins. I. Histochemical distribution of lectin binding sites in normal alimentary tract as well as in benign and malignant gastric neoplasms.

Labeled lectins with binding specificity to the hexose components of mucus glycoproteins (HPA, RCA I, PNA, Con A, WGA, and UEA I) were used to demonstrate structural differences in the glycoprotein composition of various cell types of the normal, benign and malignant gastrointestinal mucosa. While in the RCA I, UEA I, and WGA binding of normal mucus secreting cell types only quantitative differences were observed, the mucus in the surface epithelial cells of gastric mucosa and in the colonic goblet cells was characterized by the absence of PNA, Con A, and PNA, HPA binding sites, respectively. These lectins, however, showed a strong binding to the supranuclear, Golgi-region in the undifferentiated or activated forms of these cells. Even the staining intensity of the luminal membrane surfaces of the non mucinous parietal and chief cells was often stronger by PNA, HPA, and RCA I lectins than that of the mucus secretions in the highly differentiated mucus cells. These results indicate the existence of either heterogeneous glycoprotein components or mucus molecules with variations in the degree of glycosylation of their oligosaccharide chains in the different cells. The latter seems more likely since in benign and malignant alterations lectin binding sites appear in great density, which were found to be characteristic of the undifferentiated mucus cells or for the non mucinous cells of the normal gastric mucosa. Similarly in some gastric cancers which do not stain with the periodic acid-Schiff reaction at all, large amount of free or neuraminic acid substituted PNA binding sites can be detected.

Adenocarcinoma↗
PubMed1984

Characterization of glycoconjugates of human gastrointestinal mucosa by lectins. II. Lectin binding to the isolated glycoproteins of normal and malignant gastric mucosa.

Using affinity chromatography on HPA-, PNA-, Con A, and WGA-agarose columns only a part (10-30%) of the high molecular weight mucous glycoproteins could be isolated from the Triton X-100 solubilized components of normal as well as carcinomatous gastric mucosa. The main part of the mucus was not bound by the lectins, which corresponds to our earlier lectin histochemical observations on paraffin-embedded tissue sections. The lectin-bound mucous glycoproteins had a relatively lower molecular weight, ranging from about 250-1,000 kilodaltons, as indicated by polyacrylamide gradient gel electrophoresis and by gel filtration on Biogel A 1.5 m column. In gas chromatographic analysis the molar ratio of aminohexoses to galactose was found to be much higher (3:1) in the lectin-bound mucous substances than in the whole high molecular weight mucus (1:1). This finding indicates that lectins have a higher affinity to the hexosamine rich components of mucus, which may be special forms of mucous glycoprotein molecules or the incompletely glycosylated core and backbone regions of the oligosaccharide chains of mucus. Extremely high hexosamine values (10:1) were found in the PNA isolated mucus of gastric adenocarcinoma. Since it is known that PNA binds to the terminal disaccharide, beta-galactose-(1-3)-N-acetylgalactosamine, which is localized at the reducing end of the oligosaccharide chains of mucus, it is highly probable that the elongation of the oligosaccharide side chains is disturbed in gastric cancer cells.

Binding Sites↗
PubMed1983

The significance of lectin receptors for the evaluation of hormone dependence in breast cancer.

Benign and malignant breast diseases were histochemically investigated with regard to their secretory function. Thereby, the labelled lectin from peanut (peanut agglutinin = PNA) which possesses a high affinity for D-galactosyl-(1-3)-N-acetyl-D-galactosamine, showed a binding pattern partly indicating disturbed secretory cell mechanisms. Further studies with a labelled antibody directed against a milk fat globule membrane glycoprotein, which was isolated by PNA affinity chromatography from human milk, confirmed the PNA receptor as a marker of a milk protein in breast carcinomas. Additionally, two other monoclonal antibodies which were raised against other components of the milk fat globule membrane were used for a more detailed characterization of the functional situation of mammary carcinomas. These immuno- and lectin-histochemical investigations revealed that tumors with a high secretory activity responded in about 80% to endocrine treatment, whereas breast carcinomas that exhibited no secretory function failed to respond to endocrine therapy. Thereby, the hormone dependence of tumor tissue showed an inverse correlation with the proliferative activity, as determined by the mitosis index.

Arachis↗
PubMed1983

Histochemical tumor markers for evaluation of hormone dependence in breast cancer.

Lectin from the peanut (peanut agglutinin = PNA) possesses a high affinity for D-galactosyl-(1-3)-N-acetyl-D-galactosamine, used for histochemical investigations on formalin-fixed tissue sections of normal mammary gland as well as of benign and malignant breast diseases. Thereby, a lectin-binding pattern was found that partly exhibited secretory malfunction. Additional studies with a labeled antibody directed against a milk fat globule membrane glycoprotein, which was isolated by PNA affinity chromatography from human milk, confirmed the PNA receptor as a marker of a milk protein in breast carcinomas. The most important clinicopathological finding, however, was that in accordance with the secretory activity about 77% of PNA-positive tumors responded to endocrine treatment, whereas PNA-negative mammary carcinomas usually failed to show any response to hormonal therapy. These results also correlated with the hormone receptor content of tumor tissue.

Breast Neoplasms↗
PubMed1983

Peanut agglutinin (PNA) binding sites: a useful marker for hormonal dependence in experimental breast cancer.

Histochemical studies were performed with the labeled lectin from Arachis hypogaea (peanut agglutinin, PNA) to detect the occurrence, distribution, and amount of this lectin receptor in N-nitrosomethylurea-induced rat mammary carcinomas. Since in normal rat mammary tissue, the formation and secretion of PNA binding sites are controlled by the combined action of estrogen and prolactin, the amount of secretion-associated PNA binding sites was correlated with tumor response to either ovariectomy or antiestrogenic treatment with tamoxifen. Free as well as sialic acid-substituted PNA binding sites which were represented by the disaccharide beta-D-Gal(1-3)NAcGal occurred in the apical cytoplasm of tumor cells and within the secretions of acinar and tubular structures. In contrast the whole tumor cell membrane contained predominantly sialic acid-substituted PNA binding sites. All of the tumors investigated contained some secretion-associated PNA binding sites. The values showed a continuum from very low to very high amounts. The number of PNA binding sites associated with secretory activity was lower in hormone-independent than in hormone-dependent tumors. Furthermore, there was an inverse relationship between mitotic and secretory activities with positive PNA staining. In conclusion, these studies revealed that the secretory PNA index, mitotic index, and especially the ratio of secretory PNA index to mitotic index represent useful parameters to select tumors for endocrine therapy in this experimental model.

Animals↗
PubMed1983

Histochemical demonstration of neuraminidase effects in pneumococcal meningitis.

In three cases of pneumococcal meningitis the in vivo action of pneumococcal neuraminidase could be demonstrated. The removal of sialic acid was demonstrated in necrospy material by the use of labeled peanut agglutinin, which has a high specific affinity for the subterminal disaccharide beta-D-galactopyranosyl-(1-3)N-acetyl-D-galactosamine, thereby exposed. Furthermore, this lectin was used for a rapid in vitro histochemical assay of neuraminidase activity in cerebrospinal fluid and culture medium taken from these cases. From the clinical point of view the exposure of the disaccharide which represents the immunodominant group of the Thomsen-Friedenreich antigen may induce immunologic reactions, because all human sera contain antibodies to this cryptic antigen. Thereby, neuraminidase can contribute to the poor prognosis of pneumococcal meningitis.

Choroid Plexus↗
PubMed1983

Lectin binding properties of glycoproteins in cells of normal gastric mucosa and gastric cancers: a comparative histochemical and biochemical study.

The different binding of labeled lectins to the individual cell types of the normal mucosa indicates differences in glycoprotein composition of the: a) surface epithelial cells showing various degrees of differentiation; b) cell types lying above and below the generative cell zone; c) specific membrane systems of the parietal and chief cells. The enhanced peanut agglutinin (PNA) binding of activated, hyperplastic isthmus cells, of goblet cells in intestinal metaplasia, and even of the majority of gastric cancer cells may be indicative for their common origin and for their similar functional states in glycoprotein synthesis. Lectins demonstrate differences also in the mucus structure of the main types of gastric cancers. Adenocarcinomas show similar lectin binding patterns to activated isthmus cells, but the subtypes of signet ring cells resemble mucus neck cells or intestinal and colonic goblet cells, respectively. Glycoproteins which can be isolated by the lectins in a pure form allow further detailed studies in these fields.

Binding Sites↗
PubMed1982

[The pathogenetic importance of peanut lectin binding sites in infectious, toxic and neoplastic processes].

Labelled lectins are generally used for identification of mono-, oligo- and polysaccharides in histochemistry. The aim of this work is to demonstrate in addition the importance of the labelled (FITC and peroxidase) lectin from peanut (peanut agglutinin = PNA) with regard to the pathogenesis of some infectious and neoplastic diseases. Thereby, PNA-binding sites have been shown as differentiation marker in embryonic kidneys and in dysontogenetic.

Arachis↗
PubMed1980

The significance of lectin receptors in the kidney and in hypernephroma (renal adenocarcinoma).

Normal kidney tissue as well as hypernephromas were examined histochemically for the occurrence of lectin receptors. FITC- and rhodamine-labeled peanut agglutinin (PNA) and Ricinus communis agglutinin (RCA) were used for labeling different carbohydrate residues which may be of interest in the evaluation of the histogenesis of hypernephromas and possibly for concepts regarding the immunotherapy of these tumors. By using fluorescence microscopy, the receptor for PNA was found on the epithelial cells of the thin limb, distal convoluted tubules, and the collecting ducts. These binding sites occurred in a free as well as in a sialic-acid-substituted form and were mainly exposed on the luminal surface of the epithelial cells. They were absent, however, in the proximal convoluted tubules. This finding contrasts with the demonstration of RCA receptors in the brush border of these tubules. Moreover, RCA reacted with the epithelial cells of all tubules. The hypernephromas showed a wide range in the distribution and the quality of the lectin receptors, which were localized within the cytoplasm as well as in the cell membrane of the tumor cells. As demonstrated by our histochemical investigations, these kidney neoplasms may originate from any part of the tubules, and not only from the epithelial cells of the proximal convoluted tubules, as was suggested by earlier findings that employed antibodies against the brush-border antigens. In addition, the demonstration of sialic-acid-substituted and, in particular, of free PNA-receptors, which represent the immunodominant group of the Thomsen-Friedenreich antigen, may supply useful information on an immunotherapy concept.

Adenocarcinoma↗
PubMed1980

Isolation, characterization and implications of anti-TF (Thomsen-Friedenreich) agglutinins from different sources.

Anti-TF agglutinins from peanut (Arachis hypogaea) and from vertebrate sera of different species have been successfully isolated by affinity chromatography on acid-activated Sepharose 4 B. The proteins were characterized by immunoelectrophoresis, polyacrylamide gel electrophoresis in the presence of SDS and with respect to their carbohydrate binding specificities. Anti-TF substances from sera showed one precipitin arc in immunoelectrophoresis, but quantitative immunoprecipitation revealed our human anti-TF to be a mixture of the three Ig-classes IgG, IgA and IgM. This finding was confirmed on SDS gel electrophoresis, where high molecular weight aggregates were found before reduction. Hemagglutination inhibition revealed that all isolated anti-TF compounds exhibit an exceptionally high affinity for the immunodominant group of the TF-antigen, namely the beta-D-galactosyl-(1 leads to 3)-N-acetyl-D-galactosamine disaccharide. On examination of formalin-fixed and neuraminidase treated tissue sections (kidney, mammary gland), fluorescein-labelled anti-TF from horse serum showed a virtually identical pattern when compared with fluorescein labelled peanut lectin. Likewise isolated IgA-class myeloma J 539, which shows specificity against beta-(1 leads to 6)-galactans, only bound to the appropriate Gal-beta-(1 leads to 6)-Gal structures, such as those found on bovine lung or the albumin gland of Helix pomatia. Rabbit anti-VCN (Vibrio cholerae neuraminidase) activity could be selectively abolished by beta-galactosyl-containing inhibitors, whereas papain F(ab) fragments from rabbit anti-VCN immunoglobulin did not compete with anti-TF for binding sites on VCN-treated human red cells. Anti-TF, on the other hand, did not compete with anti-VCN for active VCN.

Agglutinins↗