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B Schutte

Publications and source records attributed to B Schutte.

At least 73 records · Page 4Linked to original sources
PubMed1988

Effect of short-term dietary administration of butylated hydroxyanisole on cell kinetic parameters in rat gastro-intestinal tract, assessed by immunocytochemistry and flow cytometry.

Groups of five male Wistar rats weighing 306 +/- 17 g were fed a diet containing 2% 2-(3)-tert-butyl-4-hydroxyanisole (BHA) or basal diet (control group) for 2 weeks. Subsequently, rats received an i.p. injection of 25 mg/kg bromodeoxyuridine (BrdU), a thymidine analogue, and were killed after 4 h. The gastro-intestinal tract was removed and fixed in 70% ethanol. After pepsin digestion of the fixed tissues, labelled cell nuclei were visualized by means of a monoclonal anti-BrdU antibody technique. Cell kinetic parameters were determined by means of bivariate BrdU/DNA analysis using flow cytometry. Mean labelling index and potential doubling time of forestomach cells were significantly increased (P less than 0.002) in the 2% BHA group as compared to control rats. Cell kinetic parameters in other organs--glandular stomach, ileum, caecum and colon--were not affected by short-term consumption of BHA.

Animals↗
PubMed1988

The cytokinetic behavior of donor hepatocytes after syngenic hepatocyte transplantation into the spleen.

The cytokinetic behavior of isolated hepatocytes transplanted into the spleen of syngenic normal Wistar rats was studied. Hepatocyte transplantation (HTX) was performed by the intrasplenic injection of 10(7) isolated hepatocytes. The proliferation index (PI) of intrasplenic donor hepatocytes was assessed by immunocytochemical visualization of DNA-synthesizing cells after pulse-labeling with bromodeoxyuridine (BrdU), a thymidine analogue. A method for determination of intrasplenic liver mass based on tissue glutamate dehydrogenase content was developed. The spontaneous PI of donor hepatocytes at 12 and at 20 weeks post-HTX amounted to around 3%. A significant increase of intrasplenic liver mass was demonstrated between the 12th and 20th week post-HTX (from 8.1 +/- 0.8% to 10.8 +/- 0.8% of spleen weight, P less than 0.05). After partial hepatectomy (PH) at 12 weeks post-HTX, the PI of liver cells in the spleen showed a transient increase up to about 10%, which rapidly declined to the "spontaneous" level of 3%. However, PH did not cause an additional increase in intrasplenic liver mass. This study shows that continuous mitotic activity of intrasplenic hepatocytes results in an actual increase of liver mass in spleen. Although a short-lived increase of proliferative activity of ectopically grafted hepatocytes was shown to occur after PH in the HTX-treated rat, this procedure did not result in an additional increase of intrasplenic liver tissue.

Animals↗
PubMed1988

Influence of implantation site on growth, antigen expression and metastatic potential of human colonic cancer HT29 and 5583 xenografts in nude mice.

In order to study the interaction between tumors and host environmental factors, we xenografted cells from the human colonic carcinoma cell lines HT29 and 5583-S in the subcutis, cecum, spleen and liver of nude mice and compared growth characteristics, metastatic potential and some phenotypic features of the xenografts in these sites. No remarkable differences were observed between the tumors at different inoculation sites in regard of their expression of carcinoembryonic antigen and secretory component or type of mucin produced. Also the proportion of DNA synthesizing cells as determined by bromodeoxyuridine incorporation appeared to be comparable in the studied implantation sites. Local invasive growth characteristics and metastatic potential, however, showed marked differences. Subcutaneous and cecal xenografts frequently showed tumor cell invasion into the surrounding tissue, vasoinvasive growth and discontinuous basement membrane deposition, whereas splenic and hepatic implants demonstrated more encapsulation, no invasion of blood vessels and more continuous basement membrane deposition. Subcutaneous xenografts produced no metastasis. With HT29 cells liver and lymph node metastases occurred frequently from the splenic as well as the cecal xenografts. 5583 cells regularly produced liver metastases from the splenic xenografts, whereas no metastasis from cecal xenografts were observed. We conclude that although the patterns of invasive growth and the metastatic potential differ for various implantation sites, antigen expression and cell kinetic features of tumor implants are hardly influenced by the site of inoculation.

Animals↗
PubMed1987

7-Ethoxyresorufin-O-deethylase activity in human hair roots: a potential marker for toxifying species of cytochrome P-450 isozymes.

Assay systems for the evaluation of carcinogen interaction with human tissues are essential for assessing cancer risk. Human hair roots (HHR) are a readily obtainable epithelial tissue source that have been employed for investigating inherited enzyme activities. In this study HHR were found to possess cytochrome P-450-dependent 7-ethoxyresorufin-O-deethylase (ERD) activity which measures cytochrome P-450 isoenzymes that are highly specific (in the order of greater than 95%) markers for the metabolic activation of many environmental carcinogenic substances such as the polycyclic aromatic hydrocarbons (PAHs). Topical application of PAHs (in liquor carbonis detergens) to the scalp of human volunteers was found to enhance the activity of this enzyme in freshly plucked hair roots. Oral and topical administration of ketoconazole to the same subjects resulted in an appreciable (up to 73%) inhibition of detectable enzyme activity. Our data suggest that measurement of ERD in HHR may be a useful marker for the study of toxifying species of cytochrome P-450 isozymes in human populations.

Carcinogens↗
PubMed1987

Retrospective analysis of the prognostic significance of DNA content and proliferative activity in large bowel carcinoma.

In the present study we have evaluated the prognostic significance of ploidy levels and proliferative activity in 279 cases of large bowel carcinomas which were included in a surgical prospective randomized trial. Ploidy levels and proliferative activity were determined on nuclei isolated from paraffin-embedded tissues of 279 colorectal carcinoma patients, with a mean follow-up of 51.9 months. Product limit survival analysis demonstrated a borderline significant association (P = 0.0689 by generalized Breslow; P = 0.0336 by generalized Savage) between ploidy and survival, with a 75th quantile survival of 49.8 months for patients with diploid tumors and 35.9 months for patients with aneuploid tumors. After stratification for staging, Dukes' C cases showed a statistically significant association between tumor ploidy and survival (P = 0.0224 by generalized Breslow, P = 0.0110 by generalized Savage). Product limit survival analysis for proliferative activity and survival showed a similar outcome with the strongest association in Dukes's C stage of disease (75th quantile survival of 38.9 months for low proliferative and 18.0 months for high proliferative tumors).

Aneuploidy↗
PubMed1987

Comparison of phenotypic and genotypic features in human primary large bowel carcinomas and lymph node metastases.

In order to test the contention that metastasis is a selective process and that therefore metastases might show a more restricted pattern of phenotypic and genotypic characteristics than primary tumors, we compared the expression of carcinoembryonic antigen, Ca 19-9, secretory component, serotonin, and mucin production as well as flow cytometric data on DNA content and percentage of S-phase cells in 87 primary large bowel carcinomas and their lymph node metastases. In a majority of the cases primary tumors and their metastases were largely identical with regard to the examined phenotypic features. In discrepant cases, however, metastases did not invariably show a more restricted pattern than primary tumors, indicating high differentiational plasticity of primary and metastatic colorectal cancer cells. In contrast, in a number of cases genotypic discrepancies were observed. We conclude that phenotypic characteristics of colorectal cancer cells cannot be used to study the pathogenesis of lymph node metastasis. Genotypic studies, however, suggest that lymphogenic metastasis may be a selective event.

Antigens, Neoplasm↗
PubMed1987

An improved method for the immunocytochemical detection of bromodeoxyuridine labeled nuclei using flow cytometry.

A new staining protocol is described for the immunocytochemical detection of BrdUrd labeled nuclei. Pepsin treatment of ethanol fixed cells or tissue, followed by DNA denaturation at low pH, resulted in increased sensitivity of BrdUrd staining comparable to the thermal denaturation protocol, and decreased background binding. This technique is applicable to cell suspensions, including cultured cells and bone marrow cells. Furthermore, pepsin digestion of ethanol fixed tissue fragments resulted in a high recovery of nuclei in which incorporated BrdUrd could be detected. This possibility, together with the high sensitivity, make this method especially suitable for cell kinetic studies of human solid tumors in vivo.

Acids↗
PubMed1987

Recognition of rat dendritic cells by a monoclonal antibody.

A mouse monoclonal IgM antibody reactive with dendritic cells (DC) from the Brown Norway (BN) rat was prepared. This antibody (1F119) binds to a membrane-bound antigen present on DC from thoracic duct lymph, spleen, thymus, and lymph node. The antigen is present only in low density on 5% of splenic macrophages (M phi) and absent from peritoneal M luminal diameter. In situ, the antibody exhibits a strong reactivity towards DC in the thymic medulla, whereas no reaction is observed with cortical cells. Furthermore, cells positive for 1F119 can be identified in T-cell areas of spleen, lymph node, and Peyers' patches. 1F119 was genetically restricted in that a strong reactivity was found with DC from rats of the RT1n and RT1u haplotypes, an intermediate reactivity with the RT1c haplotype, only a weak reactivity with the RT1l and RT1b haplotypes, and no reactivity with the RT1a and RT1k haplotypes. The relatively weak reactivity of 1F119 with respect to the RT1l haplotype also appeared from a weak binding of 1F119 to DC from Lewis rats, as was assessed by FACS analysis. This result was comparable to the binding of OX3 (RT1.Bl and RT1.Bu) to DC from BN rats. Studies performed on thymus sections of recombinant rat strains indicate that 1F119, despite its apparent specificity for DC, reacts with a polymorphic RT1.B product.

Animals↗
PubMed1987

Effect of tissue fixation on anti-bromodeoxyuridine immunohistochemistry.

We investigated the influence of various fixatives on monoclonal anti-BrdUrd antibody binding of BrdUrd-substituted DNA in tissue sections of routinely processed mouse small intestine after in vivo administration of BrdUrd. For denaturing fixatives such as ethanol or Carnoy's fluid, a standard denaturation protocol showed specific crypt cell labeling. With cross-linking agents such as formalin and glutaraldehyde, a remarkable increase in staining intensity was obtained after tissue digestion with pepsin before acid denaturation. The optimal pepsin concentration was determined for maximal immunoreactivity combined with acceptable morphology.

Animals↗
PubMed1987

Studies with anti-bromodeoxyuridine antibodies: II. Simultaneous immunocytochemical detection of antigen expression and DNA synthesis by in vivo labeling of mouse intestinal mucosa.

We developed a rapid and convenient immunocytochemical method for simultaneous detection of antigen expression and S-phase cells by means of anti-bromodeoxyuridine (BrdUrd) antibodies. Immunocytochemical detection of BrdUrd after in vivo administration in mice was compared with autoradiography using [3H]-BrdUrd. Both the sensitivity and specificity of the technique were high. For the dual peroxidase staining technique, DAB color modification by cobalt ions was used. We showed that antigen localization was not affected by the BrdUrd staining protocol. The technique we describe here can be performed on frozen or paraffin-embedded tissue and on cytocentrifuge preparations for analysis of the cytokinetics of phenotypically defined cells in heterogeneous populations.

Animals↗
PubMed1985

Flow cytometric determination of DNA ploidy level in nuclei isolated from paraffin-embedded tissue.

Nuclei, isolated from paraffin-embedded tissue, were stained with propidium iodide (PI) and found suitable for DNA analysis by flow cytometry (FCM). DNA-derived fluorescence intensity, however, was always decreased and had a much higher intersample variability as compared to results obtained with fresh material. Using chicken red blood cells (CRBC) as a model system, we found the lower fluorescence intensity to be due to the formalin fixation step in tissue processing. The intersample variability was found to be at least partly caused by variations in the duration of fixation. Overnight trypsinization improved the fluorescence intensity but did not reduce the intersample variability. Under all conditions tested PI binding to CRBC appeared to be saturable. Since fresh diploid or red blood cells could not be used to standardize DNA histograms, an alternative approach was developed in which nuclei from paraffin-embedded normal and tumor tissue of the same specimen were mixed. With this method DNA indices (DI) of 24 colorectal cancers were found to be closely correlated (r = 0.9877, P less than 0.001) with DI obtained with fresh tumor tissue from the same patients. The correlation of the percentages of S-phase nuclei between paraffin-extracted and fresh samples (r = 0.5875, P less than 0.05) was as high as could be expected, taking sampling differences into account. This method is an important tool for the retrospective analysis of FCM-derived DNA parameters in relation to diagnosis and prognosis of neoplasms.

Animals↗
PubMed1985

Immunofluorescence detection of liver cell membrane autoantibodies using PLC/PRF/5 cells.

Detection of liver cell membrane autoantibodies is routinely performed by immunofluorescence testing of patient sera on rabbit hepatocyte suspensions. We have investigated the possible use of cells from the PLC/PRF/5 human hepatoma cell-line. These cells were employed as substrate in an immunofluorescence test which was compared with the conventional rabbit hepatocyte assay. We found a close correlation between the results obtained with these different substrates on visual reading. We furthermore compared visual reading of immunofluorescence preparations with flow-cytometrical analysis of immunostained cell suspensions. The results with these different methods were largely confirmatory. The PLC/PRF/5 cells are easily available and should therefore be regarded as a highly valuable new substrate for detection of liver cell membrane autoantibodies. Flow cytometry appears to be a technically simple and reliable method for quantitative analysis.

Animals↗
PubMed1985

Class II antigens on canine T lymphocytes.

A panel of crossreactive anti-human, -mouse and -rat MHC class II monoclonal antibodies (Mabs) was used to examine MHC class II antigen expression on canine T lymphocytes by cytofluorometry. The presence of MHC class II antigens was demonstrated on activated T lymphoblasts as well as on non-stimulated peripheral blood T lymphocytes. A number of anti-MHC class II Mabs reacted only with activated T lymphoblasts. Immunoprecipitation studies confirmed the Ia-like or MHC class II molecular character of the antigens on canine T cells. The expression of MHC class II antigens on peripheral blood T lymphocytes appeared to be not induced by stimulation of the T cells, as purified T lymphocytes of specific pathogen free dogs reacted with anti-MHC class II Mabs. Moreover, the study indicates that MHC class II antigen expression is present in the neonatal thymus. Lectin stimulated and allogeneically stimulated T lymphoblasts showed a stronger expression of MHC class II antigens in comparison with non-stimulated T cells.

Animals↗
PubMed1984

Increased numbers of suppressor-cytotoxic cells in a patient with carbamazepine hypersensitivity.

A patient is presented with a clinical syndrome of erythroderma, fever, liver function abnormalities, eosinophilia and atypical lymphocytosis due to carbamazepine hypersensitivity. Immunological analysis of peripheral blood mononuclear cells was performed using mouse monoclonal antibodies against T-cell and Ia antigens. A 12-fold increase in the absolute numbers of suppressor-cytotoxic T-cells was found, resulting in a reversed helper/suppressor ratio. Also the number of Ia-positive cells was greatly increased. Carbamazepine may induce a reversible proliferation and activation of the suppressor-cytotoxic subset of T-cells. Implications and pathogenetic possibilities are briefly discussed.

Antibodies, Monoclonal↗
PubMed1983

Monoclonal antibody (1116 NS 19-9) defined monosialoganglioside (GICA) in colorectal carcinoma in relation to stage, histopathology and DNA flow cytometry.

Immunoreactivity of 1116 NS 19-9 monoclonal antibody defined monosialoganglioside (gastrointestinal cancer-associated antigen, GICA) has been studied in a series of colorectal carcinoma patients of a multicentre prospective controlled trial in order to assess its correlation with parameters such as localization, stage histopathological characteristics and DNA flow cytometry. GICA could be detected in 60% of the carcinomas, but no correlation was observed between its status of immunoreactivity and any of the parameters studied. It is concluded that, though study of the expression of the monosialganglioside may be worth while in relation to fundamental aspects of behaviour of colorectal carcinomas, the significance of its immunohistochemical detection in a diagnostic or prognostic sense is limited.

Antibodies, Monoclonal↗
PubMedDate not supplied

Prognostic value of cytokinetic parameters in lung cancer after in vivo bromodeoxyuridine labelling.

BACKGROUND: To improve the overall survival rate in lung cancer by adjustment of treatment protocols on basis of tumour characteristics of individual patients, independent predictive parameters are required. Therefore, we evaluated the prognostic value of cytokinetic parameters such as bromodeoxyuridine (BrdU) labelling index (LI), S-phase fraction (SPF), unlabelled S-phase fraction (USPF), S-phase duration (Ts) and potential tumour doubling time (Tpot), next to more established parameters. MATERIALS AND METHODS: To this end a series of 92 bronchoscopic specimens of in vivo BrdU labelled lung cancer patients, 72 presenting with non-small cell lung carcinoma (NSCLC) and 20 patients with small cell lung carcinoma (SCLC), were analysed flow cytometrically. Clinical as well as cytokinetic data were collected and related to survival times over a follow-up period of 2 to 7 years. RESULTS: We found that Tpot was a significant independent discriminator of good and poor prognosis in NSCLC. In particular, in non-squamous NSCLC a short Tpot, short Ts and high LI predicted for shorter survival time. In squamous cell carcinoma, a high USPF may predict a shorter survival period, although the correlation was only borderline-significant. CONCLUSIONS: We conclude that these parameters may in future be of use in drawing up more adequate treatment schedules for individual lung cancer patients.

Adult↗