An in vitro model to evaluate regulatory mechanisms of antigen expression by normal pulmonary vessel endothelial cells.
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Antigens↗
Biomedical subjects
M Ghazizadeh
Publications and source records attributed to M Ghazizadeh.
Angiogenesis and phenotypic alteration of alveolar capillary endothelium in areas of neoplastic cell spread in primary lung adenocarcinoma.
Normal alveolar capillary endothelium is quiescent in nature and displays anticoagulant thrombomodulin (TM) on its surface. The cytoplasms of these endothelial cells are ultrastructurally non-fenestrated type, and they barely express von Willebrand factor (vWf). Alveolar fibrosis is accompanied by a capillary endothelium reactive for vWf, and a loss of TM expression. In primary lung adenocarcinoma, neovascularization occurs in association with alveolar fibrosis. In order to study basic factors related to angiogenesis and phenotypic changes of the capillaries located in tumor-bearing alveolar walls, we examined 37 primary lung adenocarcinomas with electron microscopy and confocal laser scanning microscopy with antibodies for TM, vWf, vascular endothelial growth factor (VEGF), and its receptors (KDR and Flt-1), and proliferating markers (Ki-67/proliferating cell nuclear antigen). Tissues microdissected specifically from alveolar walls were used for reverse transcription-polymerase chain reaction (RT-PCR) to assess expressions of mRNA isoforms of VEGF and its receptors. New capillary branching was found by ultrastructural study in the alveolar walls in 12% of the patients. Nuclei of the capillary endothelial cells were reactive for proliferating cell markers. Endothelial fenestrae were developed in 65% of the patients, TM reactivity was lost in the alveolar capillaries, and their cell cytoplasms obtained a reactivity for vWf through a transitional mosaic-like distribution pattern of both antigens. Besides cytoplasmic VEGF expression in neoplastic cells, tumor-bearing alveolar walls showed significant expression of mRNA of VEGF165 and KDR. These findings imply that angiogenesis and phenotypic changes of the alveolar capillaries are closely related to a higher expression of tumor-associated VEGF165 and of KDR in the alveolar walls in primary lung adenocarcinoma.
Adenocarcinoma↗
Aerogenous spread of primary lung adenocarcinoma induces ultrastructural remodeling of the alveolar capillary endothelium.
To determine whether pulmonary alveolar capillaries manifest ultrastructural remodeling at areas of neoplastic invasion of primary lung adenocarcinomas, we examined 17 well-differentiated adenocarcinomas of lung (2 bronchioloalveolar and 15 papillary adenocarcinomas) by electron microscopy. The expression of vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen (PCNA) was demonstrated by immunohistochemical stainings. VEGF messenger RNA (mRNA) isoforms were detected by reverse-transcription polymerase chain reaction (RT-PCR) in alveolar walls microdissected from normal and tumor-associated tissues. Cytoplasm of neoplastic cells expressed VEGF protein in all patients. Endothelial cell nuclei of alveolar capillaries showed positive reaction for PCNA. Alveolar capillary lumina were distended like venules, and some intercellular junctions remained open. The cytoplasm of the capillary endothelial cells was enlarged and developed numerous organelles such as Weibel-Palade bodies and vesiculovacuolar organelles, in contrast to marked attenuation in their normal counterpart. Capillary sprouting occurred from proper alveolar capillaries in 2 patients. Cytoplasmic segments became extremely attenuated and developed diaphragm-like fenestrae in 65% of the patients. A relatively higher expression of diffusable isoforms of VEGF mRNA was seen in the tumor-bearing alveolar walls than in normal walls. Expression of KDR (one of the VEGF receptors) mRNA in tumor exceeded that in normal tissues. These results suggest that diffusable isoforms of VEGF mRNA released from the neoplastic cells are deeply involved in the induction of growth activity of alveolar capillary endothelial cells as much as in the characterization of tumor-associated microvessels in primary lung adenocarcinomas.
Adenocarcinoma, Bronchiolo-Alveolar↗
Apoptosis mediates decrease in cellularity during the regression of Arthus reaction in cornea.
BACKGROUND/AIMS: The Arthus type allergic reaction is characterised by inflammatory cell infiltration and marked neovascularisation in the cornea. During the healing stages, inflammatory cells and newly formed microvessels gradually disappear. The aim was to establish whether apoptosis affected the regression of inflammatory cells and newly formed microvessels, in order to define more clearly the cellular mechanisms involved in the pathobiology of corneal diseases. METHODS: Albino male rabbits were injected subcutaneously with 5 mg/ml bovine serum albumin (BSA) incorporated in Freund's complete adjuvant twice weekly. Under the anaesthesia, 30 microl of a 0.5 mg/ml BSA solution was injected into the central corneal stroma to induce an Arthus type allergic reaction. The injured corneas were collected at various time points ranging from 3 to 20 days. Apoptotic cells were identified by both light microscopy using in situ TdT-dUTP nick end labelling (TUNEL) method and electron microscopy. RESULTS: With increasing time after induction of the Arthus reaction, marked neovascularisation and infiltrated inflammatory cells such as polymorphonuclear cells (PMNs) and plasma cells were observed in the cornea. Thereafter, the inflammatory cells and newly formed microvessels gradually disappeared. Coincidently, the numbers of microvessel endothelial cells and infiltrated inflammatory cells undergoing apoptosis were increased. Apoptotic bodies were taken up by macrophages, PMNs, as well as myofibroblasts derived presumably from transformation of migrated keratocytes. CONCLUSIONS: These data demonstrate that regression of the cellular infiltrates and microvessel endothelial cells associated with the Arthus reaction in the cornea occurs via apoptosis. This finding adds insights into the cellular mechanisms regulating the pathobiology of corneal diseases.
Animals↗
Assessment of gene expression profile by cDNA microarray analysis.
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Cisplatin↗
Mosaic-like distribution of endothelial cell antigens in capillaries and juxta-alveolar microvessels in the normal human lung.
The distribution patterns of endothelial cell antigens, including thrombomodulin and von Willebrand factor (vWf), were studied in normal lung tissues obtained from distant areas of solitary nodules (seven adenocarcinomas and four hamartomas). By single immunoalkaline phosphatase and dual immunofluorescence stainings, the plasma membranes of alveolar capillary endothelium showed linear distribution of thrombomodulin, but their cytoplasm was rarely reactive for vWf (thrombomodulin-dominant pattern). Microvessels with a diameter larger than 10 microm located in the connective tissue zones demonstrated band-like reaction for vWf in their cytoplasm, and their plasma membranes often lacked reactivity for thrombomodulin (vWf-dominant pattern). The juxta-alveolar microvessels located along the borders between the alveolar- and connective-tissue zones showed mosaic-like pattern of distribution for these antigens. The pulmonary venules and peribronchial microvessels measuring up to 40 microm in diameter, demonstrated the expression of thrombomodulin along the plasma membrane, and that of vWf in the cytoplasm. Capillaries of the bronchial circulation were also characterized by mosaic-like pattern of distribution. Both antigens were often expressed in a single cytoplasmic segment. The heterogeneous distribution pattern of these antigens suggests topographic difference in endothelial cell function to maintain coagulatory and anticoagulatory balance in the normal human lung.
Adult↗
Prognostic significance of vascular endothelial growth factor expression in human ovarian carcinoma.
The influence of vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) on prognosis and the relationship between VEGF expression and MVD in ovarian carcinoma are not well defined. We studied VEGF expression in parallel with MVD by immunohistochemistry in 94 ovarian tumours (64 malignant, 13 borderline, and 17 benign) and correlated the results with the clinicopathologic prognostic factors of the disease to clarify their significance in this disease. Assessment of VEGF mRNA isoforms by RT-PCR was also performed. Of the malignant, borderline, and benign ovarian tumours respectively, two (3%), four (31%) and 16 (94%) were negative, 31 (48%), seven (54%) and one (6%) had low expressions, and 31 (48%), two (15%) and none (0%) had high expressions of VEGF. There were significant associations between the VEGF expression and disease stage (P= 0.002), histologic grade (P= 0.0004), and patient outcome (P= 0.0002). MVD did not correlate significantly with the clinicopathologic parameters. Likewise, no correlation was found between MVD and VEGF expression. The survival of patients with high VEGF expression was significantly worse than that of patients with low and negative VEGF expression (P = 0.0004). Multivariate analysis revealed that disease stage and VEGF expression were significant and independent prognostic indicators of overall survival time (P = 0.008 and P = 0.006 respectively). These findings suggest that in conjunction with the established clinicopathologic prognostic parameters of ovarian carcinoma, VEGF expression may enhance the predictability of patients at high risk for tumour progression who are potential candidates for further aggressive therapy.
Adult↗
Heterogeneous distribution of thrombomodulin and von Willebrand factor in endothelial cells in the human pulmonary microvessels.
Laser scanning confocal fluorescence microscopy techniques were used to study the localization of von Willebrand factor (vWf; Factor VIII-related antigen) and thrombomodulin (transmembrane receptor for thrombin) in the microvascular endothelial cells in the normal human lung. Tissues were obtained from lobectomy specimens resected for solitary nodules (7 adenocarcinomas and 4 hamartomas) from 11 patients. The plasma membranes of the capillary endothelial cells in the alveolar zones (A-zones) showed red linear fluorescence for thrombomodulin. However, their cytoplasm was mostly unreactive for vWf. The microvessels which were located in the connective tissue (C-zones), including peribronchial, and subpleural areas and large vascular walls, consistently demonstrated band-like green fluorescence for vWf in their cytoplasm, and their plasma membranes usually lacked reactivity for thrombomodulin. Only a limited number of peribronchial capillaries measuring <10 microm in diameter showed a mosaic-like appearance, in which red fluorescence along the plasma membranes was found together with green fluorescence in the subjacent cytoplasm. In the juxtaalveolar (J-zones) microvessels located along the borders between A- and C-zones, and measuring up to 40 microm in diameter, the endothelial cells showed a mosaic-like pattern of distribution of the two antigens. However, the localization of thrombomodulin in the J-zone microvessels was separate and independent from that of vWf. The thrombomodulin-reactive cells were directly connected to the alveolar capillary endothelial cells. Heterogeneous patterns of distribution of thrombomodulin and vWf suggest that topographic differences of endothelial function occur to maintain a balance of coagulation and anticoagulation in the normal human lung.
Adult↗
Comparative genomic hybridization analysis of cisplatin-resistant ovarian carcinoma cells.
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Carcinoma↗
Ultrastructural characteristics of myocardial and coronary microvascular lesions in Kawasaki disease.
Kawasaki disease (KD) is an acute febrile mucocutaneous lymph node syndrome with multisystemic vasculitis affecting mainly infants and children. Although several studies on cardiovascular lesions in KD have been done at the light microscopic level, the ultrastructural characteristics and incidences of these lesions have not been well defined. In order to investigate the myocardial and coronary microvascular sequelae in KD, we performed an ultrastructural study on endomyocardial biopsy specimens obtained during follow-up from 54 patients who had typical clinical manifestations of KD, of whom 47 had associated coronary aneurysms as demonstrated by coronary arteriography (CAG) or two-dimensional echocardiography in the acute or healed stage. The average age of onset was 2.2 years old and the duration of illness was from 2 months to 23 years. Follow-up CAG showed that the coronary aneurysms persisted in 33 of the 47 patients (8 with associated stenosis) and resolved in the remaining 14 patients. Ultrastructurally, the myocardial changes revealed hypertrophy, various degrees of degeneration, proliferation and abnormality of mitochondria, infiltration of a small number of lymphocytes, and fibrosis. The coronary microvascular lesion was characterized by microvascular dilatation, endothelial cell injury, platelet aggregation with thrombosis, and stenotic lumen with thickened walls in the small arterioles. It persisted after convalescent stage even up to 23 years and closely correlated with the myocardial sequelae. Moreover, significantly increased incidences of myocardial and coronary microvascular lesions were found in patients with coronary artery lesion. These findings suggest the coronary microvascular lesion as a possible underlying factor of persistent sequelae in KD.
Adolescent↗
Specific role of T and Tn tumor-associated antigens in adhesion between a human breast carcinoma cell line and a normal human breast epithelial cell line.
The possibility that tumor-associated antigens T and Tn act as adhesion molecules between normal and malignant breast epithelial cells at the early stages of recognition in the metastatic pathway was examined in vitro. The adhesive specificity of the antigens was assessed by means of in vitro adhesion tests between a carcinomatous breast cancer cell line (ZR75-30) and a normal epithelial breast cell line (HLB100) using both monoclonal antibodies and lectins specific as well as nonspecific for each antigen. Adhesion assay was performed using monolayers of the normal cell line prepared on plastic culture plates and the tumor cell line labeled with a fluorescent dye as a probe. The adhesion between the two cell types occurred with significant specificity via T and Tn antigens (P<0.001), and was temperature-dependent. The results suggest that at the early stages of recognition by tumor cells in the metastatic process, T and Tn antigens play a role as adhesion molecules between the tumor cells and adjacent normal cells.
Antibodies, Monoclonal↗
Contact-angle analysis of intraocular lenses.
PURPOSE: To present contact-angle measurements of commercially available intraocular lenses (IOLs) in air and in water to facilitate the understanding of how various IOLs might interact in different environments. SETTING: Laboratory. METHODS: Five commercially available IOLs were studied: AMO DuraLens PS-59NB. AMO PhacoFlex SI-26NB, AMO PhacoFlex II SI-30NB, Chiron ChiroFlex C10UB, and Alcon AcrySof MA60BM. The AMO soft acrylic model AR40, currently under clinical study, was also evaluated. Contact-angle measurements were made in air and in water using sessile drop and captive bubble methods. RESULTS: The sessile drop method indicated that all materials were hydrophobic in air. The captive bubble method differentiated materials based on their polar and dispersive forces. CONCLUSION: Contact-angle measurements differed depending on the test conditions. Proper choice of contact-angle measurement method can generate useful information about a material surface and its potential biomaterial interactions.
Acrylates↗
Immunohistochemical and ultrastructural studies of basal cells, Clara cells and bronchiolar cuboidal cells in normal human airways.
Immunohistochemical studies were made of the distribution of various cytokeratins (CK), Clara cell secretory protein (CC10), surfactant protein A (SP-A) and type VII collagen in normal human airways. Electron microscopic studies were made to identify hemidesmosomes and anchoring fibrils on the basal surfaces of the epithelial cells. CK19 was detected in all epithelial cells, and CK17 in all basal cells. CK14 was coexpressed in a few basal cells, and this coexpression was decreased in the distal airways. Two types of basal cells were recognized. One type, found mainly in large airways, was characterized by abundant intermediate filaments and well-developed hemidesmosomes and anchoring fibrils. The second type contained few intermediate filaments and poorly developed hemidesmosomes and anchoring fibrils. Reactivity for type VII collagen was found along the basement membrane throughout the airways, but not in the alveoli. Clara cells were reactive for CC10 and CK17, but not for CK14 and SP-A. The bronchiolar cuboidal cells in the respiratory bronchioles were positive only for CK19. Surfactant protein A was present only in type II alveolar epithelial cells. Thus, two types of basal cells are present in airways, and the bronchiolar cuboidal cells appear distinct from these basal cells, Clara cells and type II alveolar epithelial cells.
Adult↗
Interphase cytogenetic and AgNOR analyses of hydatidiform moles.
AIM: To determine the potential value of interphase cytogenetic and argyrophilic nucleolar organiser region (AgNOR) analyses in the diagnosis and classification of hydatidiform moles. METHODS: Serial tissue sections from 37 hydatidiform moles, histologically classified as 11 complete and 15 partial, and from 11 hydropic abortuses were examined by in situ hybridisation using digoxigenin labelled probes specific for chromosomes 1, X, and Y, and a one step silver staining method. The percentages of diploid and triploid nuclei, and the mean number of AgNORs for each tissue were determined. RESULTS: Interphase cytogenetics showed that eight of the 11 cases (73%) each of complete mole and hydropic abortus had diploid pattern and the three remaining cases (27%) of each group were triploid. Two of the triploid complete moles and one of the triploid hydropic abortuses were revised to partial moles and one remaining triploid complete mole was revised to hydropic abortus. Of the 15 partial moles, nine (60%) were triploid, and six (40%) were diploid. These diploid cases were revised to three complete moles and three hydropic abortuses. There was a significant difference (p < 0.0001) between the mean (SD) AgNOR count in partial mole (5.11 (0.91)) versus hydropic abortus (3.79 (0.90)) and complete mole (3.39 (0.97)). The total of 15 triploid cases showed a high mean AgNOR count of 5.24 (0.73). Also, after reclassification, eight of the nine partial moles (89%) had a mean AgNOR count of > or = 5. The results of analyses by the two methods were closely correlated. CONCLUSIONS: Interphasecytogeneticanalysis using chromosome specific probes and AgNOR count provides a valuable approach for ploidy analysis in histological sections of hydatidiform moles and helps to resolve difficult cases.
Analysis of Variance↗
Mucin carbohydrate antigens (T, Tn, and sialyl-Tn) in human ovarian carcinomas: relationship with histopathology and prognosis.
Altered glycosylation of mucins leading to the expression of T, Tn, and sialyl-Tn antigens has been shown in ovarian carcinoma, but its relationship with prognosis is still unclear. We investigated immunohistochemically the expression of these antigens in 38 (17 serous and 21 mucinous) ovarian carcinomas to assess their potential prognostic value as compared with stage of disease, histopathology of tumors, and survival time of patients. Eight benign ovarian tumors (four serous and four mucinous), and four normal ovarian tissues also were studied. Of the 38 carcinomas, 25 (66%) expressed T, 27 (71%) expressed Tn, and 33 (87%) expressed sialyl-Tn antigens. Most cases (83%) expressed two or all of the three types of antigens simultaneously. Normal ovarian epithelia showed no staining for these antigens, and benign ovarian tumors were either negative or occasionally expressed weak staining in less than 25% of epithelial cell areas. Statistical analyses showed strong associations between Tn and sialyl-Tn antigen expressions and disease stage as well as histological grade. In 19 ovarian carcinoma patients with available survival data, the overall survival times of patients with high Tn or sialyl-Tn antigen expression were significantly worse than those of the patients with negative and low expression (P < .05 and P < .01). In multivariate stepwise regression analysis, disease stage (P = .000) and Tn antigen expression (P = .02) were found to be significant independent parameters associated with the overall survival time. These findings suggest that, with exception of T antigen expression, the expression of Tn and sialyl-Tn antigens in ovarian carcinomas may provide additional prognostic information on patient outcome.
Antigens, Tumor-Associated, Carbohydrate↗
Optimizing collagen antigen unmasking in paraffin-embedded tissues.
In order to optimize collagen antigen unmasking in paraffin-embedded tissue sections, the effects of various fixatives and duration of fixation in relation to enzyme pretreatment and microwave irradiation for collagen antigen unmasking were studied. A streptavidin-biotin-peroxidase complex method was used for the immunolocalization of type III and IV collagen antigens. Fixatives and fixation time had significant adverse effects on the immunoreactivity of the antigens. Enzyme pretreatment was found to be superior to microwave irradiation for collagen antigen unmasking. Fixation with paraformaldehyde required shorter enzyme pretreatment and yielded a more enhanced reaction than treatment with formalin and Bouin's fluid. The optimum conditions for type III and IV collagen unmasking were found to be fixation with 4% paraformaldehyde in 0.01 M phosphate-buffered saline, pH 7.4, for up to 3 weeks followed by enzyme pretreatment with 1 mg ml-1 pepsin in 0.01 N hydrochloric acid, pH 2.0, for 30 min (human tissues) or 60 min (rat tissues) at 37 degrees C. It is concluded that collagen antigen unmasking by enzyme pretreatment in tissue sections fixed for a long period of time can be successful if appropriate enzyme(s) and incubation time(s) are employed with regard to the antigen under study and fixative and fixation time used for tissue preparation.
Animals↗
Prognostic value of proliferative activity of ovarian carcinoma as revealed by PCNA and AgNOR analyses.
Proliferative activity of a malignant tumor is known to reflect its biologic aggressiveness. Proliferating cell nuclear antigen (PCNA) is a marker of cellular proliferation, and silver-stained nucleolar organizer regions (AgNORs) have been shown to correlate with ploidy and proliferative activity of cells depending on the method of assessment; the mean number of AgNORs per nucleus reflects ploidy, whereas the mean percentage of nuclei with five or more AgNORs per nucleus indicates proliferative activity. In ovarian carcinoma, the prognostic value of these markers has not been well defined. We studied PCNA expression and the AgNOR count in 43 ovarian carcinomas (25 serous, 13 mucinous, and 5 clear cell types) to assess their potential prognostic significance compared with the stage of disease and histopathologic features of the tumors. Eight benign (four serous and four mucinous) and six normal ovarian tissues were also evaluated. A standard colloidal silver staining and an immunohistochemical method were used. The mean percentage of PCNA positivity (PCNA index), the mean number of AgNORs per nucleus (mAgNOR), and the mean percentage of nuclei with more than five AgNORs per nucleus (pAgNOR) for each lesion were determined. In univariable analysis, PCNA indexes and mAgNOR and pAgNOR values were significantly higher in benign ovarian tumors compared with normal ovarian tissues and in adenocarcinomas compared with benign ovarian tumors. In multivariable analysis, PCNA indexes were significantly associated with histologic grade (P=.003), whereas associations of mAgNOR and pAgNOR values were highly significant with both histologic grade and disease stage (P=.0001). Histologic grade, but not subtype, was also associated with disease stage at a significant level (P=.008). Our findings indicate that differences in biologic behavior of ovarian carcinomas may, in part, be defined by differences in their ploidy and proliferative activity, and that whereas PCNA expression is of limited value, assessment of AgNORs holds promise in providing valuable prognostic information on the biologic behavior of the tumors.
Adenocarcinoma, Clear Cell↗
Silver-stained nucleolar organizer regions in hypertrophic and keloid scars.
Silver-stained nucleolar organizer regions (AgNORs) have been widely used as a marker of cellular activity and proliferation. In a retrospective study, we investigated the potential value of AgNORs in 12 hypertrophic and 24 keloid scar tissues. Ten normal skin tissues served as controls. A standard silver-staining method was used, and the mean AgNOR count of dermal fibroblastic cells in each tissue was determined. In normal skin, the mean AgNOR count of dermal fibroblasts was 1.79+/-0.55, whereas fibroblastic cells in hypertrophic and keloid scars had mean AgNOR counts of 3.18+/-0.56 and 5.10+/-0.97, respectively. There was a statistically significant difference between the mean AgNOR counts of fibroblastic cells from normal skin, hypertrophic scar, and keloid scar [one-factor analysis of variance (ANOVA), p < 0.0001]. Our findings suggest that AgNOR count may be a useful marker for assessment of fibroblastic cell activity in hypertrophic and keloid scars, which may have potential value for histologic and biologic characterization of the two lesions.
Analysis of Variance↗