A comparative quantitative analysis of laminin-5 in the basement membrane of normal, hyperplastic, and malignant oral mucosa by confocal immunofluorescence imaging.

Laminin-5 (Ln-5) is a heterotrimeric basement membrane (BM) molecule (alpha3beta3gamma2). It is a principal protein constituent of the anchoring filaments, which connect the BM with the hemidesmosomes of the basal keratinocytes and possess a crucial function in keratinocyte adhesion. Confocal immunofluorescence imaging is introduced for a quantitative evaluation of the Ln-5 content in the BM of oral squamous epithelium. The BM of normal oral mucosa was used as a reference (100%) for comparative analysis and showed a nearly uniform Ln-5 immunofluorescence intensity (99-100%). In all hyperplastic lesions of oral mucosa, the Ln-5 immunofluorescence intensity was increased (107-141%). The increased Ln-5 content in the BM of hyperplastic lesions suggests an increased keratinocyte-BM adhesion, possibly resulting in a higher stability of the oral mucosa. In contrast, in the oral squamous cell carcinoma (OSCC) invasive front, the remaining BM segments were characterized by a decrease in Ln-5 immunofluorescence intensity (35-74%). A stronger decrease of Ln-5-linked kerationocyte-BM adhesion correlates with a higher tumor grade. Because in central areas of carcinoma BM segments with a normal Ln-5 content could be demonstrated, the fundamental Ln-5 diminution in BM segments of the invasive front should be considered as an invasion-associated phenomenon.

The association between tumour progression and vascularity in myxofibrosarcoma and myxoid/round cell liposarcoma.

Angiogenesis is an important factor in the morphological progression and metastasis of many solid tumours. We studied two homogeneous series of myxofibrosarcoma (MFS) and myxoid/round liposarcoma (MRLS), characterised by distinct vascular patterns and correlated the intratumoral microvessel density (IMD) with morphologic progression in both types of sarcoma. In our study, 43 cases of MFS and 42 cases of MRLS were graded according to established diagnostic criteria. For evaluation of IMD, representative sections were stained immunohistochemically for CD31. After selection of "neovascular hot spots", IMD was calculated by measuring the endothelial surface within twenty 200x fields in relation to the total analysed area. In addition to the correlation of IMD with histological grades of malignancy, a correlation of IMD with the inflammatory infiltrate in MFS was done. To determine whether vascular endothelial growth factor (VEGF) and its receptors, KDR and flt-1, may play a role in the progression of both types of sarcomas, we used mRNA in situ hybridisation (ISH) to study VEGF, KDR and flt-1 expression in selected cases. In addition, the expression of thrombospondin-1, which has been reported to inhibit angiogenesis, and of collagen type I was studied using mRNA ISH. Cases of MFS varied histologically from hypocellular, mainly myxoid, neoplasms (low-grade malignant, 18 cases) to intermediate-grade malignant lesions with increased cellularity and mitotic activity (13 cases), and high-grade malignant cases with marked pleomorphism, high proliferative activity and areas of necrosis in many cases (12 cases). Cases of purely low-grade myxoid liposarcoma (16 cases) were characterised by low-cellularity, mucin pooling and plexiform vasculature. In combined MRLS, these hypocellular areas were admixed with hypercellular, round cell areas (5-80% of the analysed tumour area; 23 cases), and in round cell liposarcoma (three cases) rounded tumour cells predominated (>80% of the analysed tumour area). The average IMD in intermediate and high-grade malignant MFS (4.03 and 4.09, respectively) was significantly higher than in low-grade malignant MFS (2.73). Correlation of vascularity with the inflammatory infiltrate in MFS showed increased IMD only in cases with abundant neutrophils; most of these cases were high-grade malignant neoplasms. In contrast, no statistical correlation between morphological progression and IMD was seen in myxoid liposarcoma (6.08), MRLS (6.57) and round cell liposarcoma (4.07). VEGF mRNA was expressed by tumour cells in all histological grades of MFS and MRLS. VEGF receptor mRNA was weakly expressed by endothelia of newly formed blood vessels in both entities. Interestingly, tumour cells of all analysed cases of MFS strongly expressed collagen type I and thrombospondin-1, while these proteins were not detected in tumour cells of MRLS. In conclusion, morphologic tumour progression in MFS is associated with increased IMD, whereas, in MRLS, no such correlation is seen. Whereas VEGF and VEGF receptor mRNA were expressed in both entities, a characteristic expression profile of collagen type I and thrombospondin-1 in MFS emerged. Further studies are necessary to correlate vascularity and clinical course in MFS and MRLS.

123I-antileukoproteinase scintigraphy reveals microscopic cartilage alterations in the contralateral knee joint of rats with "monarticular" antigen-induced arthritis.

OBJECTIVE: To assess the involvement of the contralateral knee joint in monarticular antigen-induced arthritis (AIA) by scintigraphy with the cationic (pI >10), 123I-labeled, serine proteinase inhibitor antileukoproteinase (123I-ALP) and to compare the scintigraphic findings with those of radiography and high-resolution ex vivo magnetic resonance imaging (MRI). METHODS: Lewis rats with chronic AIA were examined 2.5 months following arthritis induction (injection of 500 microg of methylated bovine serum albumin/saline into the ipsilateral [arthritic] knee joint and injection of phosphate buffered saline into the contralateral knee joint following systemic immunization). 123I-ALP was injected intravenously into normal rats (n = 4) or rats with AIA (n = 6). The ipsilateral and contralateral knee joints and both ankles were examined by scintigraphy and radiography. Joint cartilage was examined by high-resolution ex vivo MRI, histopathology, and measurement of tissue radioactivity. RESULTS: ALP accumulation (typically observed in normal articular cartilage) was lost in both the ipsilateral and the contralateral knee joints, but not in the clinically unaffected ankles of rats with AIA. In both knee joints, 123I-ALP target:background ratios and cartilage radioactivity correlated negatively with the loss of toluidine blue staining in cartilage, which documents the depletion of charged matrix molecules. Findings of histopathology confirmed mild alterations in the ipsilateral knee joint and even milder alterations in the contralateral knee joint, while the ankles were normal. Radiography and high-resolution ex vivo MRI failed to detect abnormalities in the contralateral knee joint. CONCLUSION: Loss of ALP accumulation appears to document proteoglycan depletion, even in the microscopically altered cartilage of the contralateral knee joint in AIA. These findings underscore the high sensitivity of 123I-ALP for in vivo detection of biochemical cartilage alterations in arthritis, and furthermore, question the use of the contralateral knee joint as a normal control in AIA.

[Laminin-5 in diseases of the oral cavity]. / Laminin-5 bei Erkrankungen der Mundhöhle.

The basement membrane molecule laminin forms a family of proteins. Laminin-5 was identified as key protein in the anchoring filaments of the basement membrane. The anchoring filaments connect the basement membrane to the epithelial cells and together form the epithelial adhesion complex. Disturbances in the epithelial adhesion complex result in subepithelial blistering dermatosis. Autoantibodies against laminin-5 are found in cicatricial pemphigoid. Mutations in genes of laminin-5 with loss of the protein cause epidermolysis bullosa Herlitz. It can be determined during prenatal genetic diagnostic testing. Laminin-5 supports migration of keratinocytes and forms the basis for migrating keratinocytes in oral wound healing. Positive re-epithelialization via laminin-5 has been the subject of experimental studies. Oral squamous cell carcinomas are found to have a focal loss of laminin-5 in conjunction with a loss of the cellular receptor, and increased synthesis of laminin-5 by budding tumor cells has been observed along with deposition of the protein in the stroma. As a result of these observations laminin-5 has been suggested as a route of invasion. Quantitative assessment of this phenomenon and the modulation of laminin-5-tumor cell interaction offer new and hopeful means of describing and affecting the invasive behaviour of oral squamous carcinoma.

Experimental studies on the stem cell concept of liver regeneration. II.

There is increasing evidence in support of the existence of a hepatic stem or progenitor cell system as well as its participation in the physiological as well as reparative regeneration of the liver and in carcinogenesis. In the present paper it will be demonstrated that under the condition of a simultaneous intoxication with allyl alcohol and tetrachlorcarbon a regenerative process occurs, which is composed of two distinct partial processes: 1. a "proliferative wave" of the persisting, non-necrotic differentiated hepatocytes of the acinus, starting at 24 h after intoxication and ending after >48 h, and 2. a proliferation of cells at the rim of the portal fields, which afterwards enter the acinus and differentiate into hepatocytes, starting at 48 h after intoxication. These results support the participation of a stem or progenitor cell system in the reparative regeneration of the liver.

Evaluation of microvessel density by computerised image analysis in human renal cell carcinoma. Correlation to pT category, nuclear grade, proliferative activity and occurrence of metastasis.

A high microvessel density is suspected to favour tumour progression and the occurrence of metastasis. To elucidate the significance of abundant vessels for the behaviour of human renal carcinomas, the microvessel density of 110 renal cell carcinomas was correlated to pT category, nuclear grade, proliferative activity, occurrence of metastasis and relapse-free survival interval. The microvessels were quantified using CD31 immunostaining of endothelial cells and computer-aided image analysis. The rules for reproducible microvessel counting, as defined by Weidner, were strictly observed. A statistically significant relationship between the microvessel density and nuclear grade, proliferative activity, occurrence of metastasis and relapse-free survival was found; only for tumour size could no such relation be seen. Perplexingly, there is a diminution of microvessel density in association with increasing nuclear grade, proliferative activity, relapse-free survival interval and frequency of metastasis. This finding is contradictory to the hypothesis that an increasing microvessel density indicates a worsening prognosis.

Experimental studies on the stem cell concept of liver regeneration. I.

There are increasing references for the existence of a hepatic stem or progenitor cell system as well as its participation in the physiological as well as reparative regeneration of the liver and in carcinogenesis. For the physiological regeneration the existence of a dynamic "cell-renewal" system finds increasing consideration and in the "streaming liver concept" (Zajicek et al. 1985) its functional expression. This concept is still under discussion. The present paper tries to check this animal-experimentally (Wistar rats) under use of two different thymidine analogues (3H-thymidine and Bromodeoxyuridine). In different time intervals after labelling (1 h, 14, 30, 60, 90, 120 d) a shift of the labelling bias or a migration of the hepatocytes in the liver acinus (Rapaport) in portovenous direction could be shown. The average migration speed is 0.575 microm or 0.0315 cell positions per day, the cell production rate is one in 31.5 days. The present paper results support the inclusion of a stem or progenitor cell system into the physiological regeneration of the liver and allow the classification into the "streaming liver concept" (Zajicek et al. 1985).

Radioimmunodetection of neuroblastoma cells with I-131-radiolabelled antibodies.

The murine anti-neuroblastoma monoclonal antibodies 15/7 and 19/1/4 should be tested for specific radiolocalization of neuroblastoma by immunoscintigraphic imaging of this tumour growing in mice. Radioiodination of both antibodies was done by chloramine-T method resulted in an immunoreactivity of 75%. The calculated specific activity varied from 51.1 to 126.2 kBq/microgram IgG. In each case, about 500 kBq of labeled antibodies were intraperitoneally injected into human neuroblastoma (SK-N-MC, SK-PN-DW and IMR 5) xenografted severe complete immunodeficient (SCID) mice. Whole-body scintigraphy was performed daily by a scintiscanner to localize the tumour site. After last scanning principal organs were removed and their I-131-uptake was determined by measuring the impulse rate. The best scintigrams were done with I-131-19/1/4 at the second day after antibody injection. Radioconjugates were accumulated at highest in the tumour at the third day after application of 15/7 and 19/1/4 with a tumour uptake of 0.4 and 2.2 per cent of injected dose per gram (%ID/g), respectively. The 15/7-moAbs was accumulated approximately 9-fold higher in the SK-N-MC and SK-PN-DW grafts than in principal organs, whereas the tumour/non-tumour-ratio of the 19/1/4 moAb was 3:1. The results indicate the efficacy of these two neuroblastoma antibodies in radiolabelling and their usefulness for tumour imaging of neuroblastoma engrafted SCID-mice.

Integrin receptors and their relationship to cellular proliferation and differentiation of oral squamous cell carcinoma. A quantitative immunohistochemical study.

The expression of extracellular matrix (ECM) proteins (fibronectin, laminin, collagen IV) and ECM receptors of integrin type (alpha 2 beta 1, collagen receptor; alpha 6 chain of the fibronectin receptor; alpha 6 chain of the laminin receptor) were examined in normal oral squamous epithelium and in invasive areas of squamous cell carcinomas with various differentiation and proliferation activities (Ki-67 antigen labelling), evaluating the presence, quantity (using an image analysis system) and distribution of the integrin subunits. In the mucosa, there was uniform immunostaining for alpha 2 beta 1 and alpha 6 concentrated at the cell membrane in the basal/supra basal cell zone, whereas, alpha 5 showed a discontinuous staining of the basal cell-basement membrane interface. alpha 2 and alpha 6 could be visualized in all carcinomas. alpha 5 showed low expression preferentially in less differentiated carcinomas. In contrast to normal mucosa, there was an increase in alpha 6 staining in well-differentiated carcinomas. Dedifferentiation of oral carcinomas was accompanied by an increase in cellular proliferation and with a decrease in alpha 2 beta 1 and alpha 6 staining. This reduction of alpha 6 staining was shown to be statistically significant, suggesting that this integrin may be a valuable grading parameter for oral squamous cell carcinoma.

Experimentally induced murine rhabdomyosarcomas--correlation between cellular contacts, matrix formation and cellular differentiation.

Rhabdomyosarcomas (RMSs) consist of a mixture of primitive mesenchymal cells as well as cells showing various stages of rhabdomyomatous differentiation. The qualitative and quantitative degree of the rhabdomyomatous differentiation of the cells, evaluated by their morphology and expression of defined structural and functional proteins, is accepted as the basis of diagnosis and is considered to be related to the biological behaviour of RMSs. Therefore we investigated solid experimentally induced murine RMSs, adherent (subconfluent, confluent) cell cultures obtained therefrom, and also suspension cultures and studied the expression of muscular differentiation markers (vimentin, desmin, myoglobin) and the formation of extracellular matrix components (fibronectin, laminin). When we compared solid tumours with adherent cell cultures of decreasing cell densities (confluent up to single cells) and with cells grown in suspension, we found a gradual decline of differentiation ("dedifferentiation"). This decline paralleled the decrease of cell-cell and cell-substrate contacts. In suspension cultures, cells were prevented from interacting with each other and the substratum, no rhabdomyomatous differentiation of the cells took place. If restoration of cellular contacts was allowed, either by adherent growth or by reinoculation into nude mice, the process of dedifferentiation was completely reversible. Consequently, it was demonstrated that the increase of cell-cell and cell-substrate contacts was strongly associated with the appearance or increasing expression of the desmin intermediate filament cytoskeleton and with formation of the extracellular matrix components fibronectin and laminin. The microfilament (F-actin) system was modulated from an impressive stress-fiber system in subconfluent to a dense network in confluent monolayers. The extent of cell-substrate contacts, mediated by extracellular matrix components, and the number of cell-cell interactions are responsible for the capability of a malignant mesenchymal cell, which is able to undergo rhabdomyomatous differentiation, to achieve the various stages of maturation.

[Proliferative activity of mesenchyme and epithelium in teratogen- affected palatogenesis]. / Die proliferative Aktivität von Mesenchym und Epithel in der teratogen beeinflussten Palatogenese.

In mesenchymal cells of the palatal shelves there are two maxima with a 3H-thymidine labelling index of more than 30%. In the teratogenically altered palatogenesis there is only one peak in the labelling index one day before horizontalization of the palatal shelves. In the proliferative rate of epithelial cells are no principal differences between normogenesis and teratogen altered palatogenesis.

[Effect of propyphenazone on drug biotransformation in the liver. A comparison with phenylbutazone using the aminopyrine breath test]. / Zum Einfluss von Propyphenazon auf die Arzneimittelbiotransformation in der Leber. Eine Vergleichsstudie mit Phenylbutazon unter Verwendung des Aminopyrin-Atemtestes.

By means of the aminopyrine breath analysis the influence of phenylbutazone, propyphenazone and of the combination preparation Wofapyrin "new" on the aminopyrine-N-demethylation, a hepatic microsomal performance of biotransformation in patients with diseases of the rheumatic circle of forms was examined. The enzyme-inducing effect of phenylbutazone known from literature could be confirmed. On the other hand despite a relatively highly dosed one-week treatment propyphenazone did not lead to changes of the demethylation capacity of the liver in the majority of the patients. In individual cases increases of the capacity are possible. In general, however, the doses of propyphenazone usual in the practice for the treatment of acute feverish infections no disturbing effects of induction or inhibition on the metabolic liver functions represented by the amino-N-demethylation are to be expected. The enzyme-inducing effect of Wofapyrin "new" is to be ascribed to the phenyl-butazone component.

[Quantitative histochemical studies of islands of Langerhans in the (Psammomys obesus) in the development of diabetes mellitus. II. Surface measurement of the islands]. / Quantitativ-histochemische Untersuchungen an Langerhansschen Inseln von Sandratten (Psammomys obesus) während der Ausbildung eines Diabetes mellitus. II. Flächenmessung der Inseln.

Measurement of the islet-area are pointed out in 30 sand rats. The animals are divided in 3 groups: 8 sand rats are the reference group, 11 animals are the IGT-group (impaired glucose tolerance), and the diabetic group consists also of 11 sand rats. The islet-area is in the IGT-group increased in 173.2%. It is concluded that the islet-volume is also increased. The diabetic group is characterized by the maximal increase of the islet area (431.4%). Hyperplasia of Langerhans' islets is detectable histologically. The sand rat is a biological model of the human non-insulin-dependent diabetes mellitus (NIDDM).

[Application possibilities of an automatic image analyzer ("Quantimet 720") in bone histomorphometry]. / Untersuchungen zur Einsatzfähigkeit eines automatischen Bildanalysegerätes ("Quantimet 720") in der Knochenhistomorphometrie.

By the way of proofing of the preventive estrogen effect on the ovariectomy osteoporosis in rats the authors collected experiences in measuring of two histomorphometric parameters "trabecular bone volume" and "trabecular bone surface" with the automatic image analyser Quantimet 720. This method demands thin bone polishes or cuts, a very rich in contrast and selective colouring. The measurement with this device spares time and gives reliable results for "trabecular bone volume", but less reliable values for "trabecular bone surface".

[Quantitative histochemical study of pancreatic islets of sand rats (Psammomys obesus) in diabetes mellitus I. Cytophotometric measurement of insulin content]. / Quantitativ-histochemische Untersuchungen an Langerhansschen Inseln von Sandratten (Psammomys obesus) während der Ausbildung eines Diabetes mellitus. I. Cytophotometrische Messung des Insulingehalts.

The insulin-content in islets of Langerhans on sand rats with disturbances of the carbon hydrate tolerance (reference-, impaired glucose tolerance-, and diabetic group) is measured cytophotometrically. In the IGT-group (impaired glucose tolerance) is a decrease of the insulin content in B-cells detectable. However in the diabetic group of sand rats is the insulin-content increased. This results demonstrate the stimulation of the B-cell function in the islets of Langerhans. The diabetes mellitus of sand rats is characterized by disturbed glucose tolerance hyperinsulinaemia, and elevated readiness to insulin secretion. That are characteristics of the human type-II-diabetes (insulin-independent). In conclusion, the sand rat is a biological model of the human type-II-diabetes (NIDDM).

[Effect of the photometric resolution on the precision of microphotometric measurements]. / Untersuchungen zum Einfluss der photometrischen Auflösung auf die Genauigkeit mikrophotometrischer Messungen.

From investigations on microautoradiographs of suitable biological structures, it is concluded, that for the determination of photometric quantities without loss of accuracy a photometric resolution of n = 10 intervals of optical density is sufficient. A low photometric resolution allows to represent the local distribution of substances more clear and the expense of analysis is reduced.

Interference microscopic determination of the section thickness of different paraffin-embedded organ tissues.

With respect to the significance of the section thickness in quantitative-morphological studies the thickness of different paraffin-embedded tissue sections was determined by interference microscopy. Within the range of 3-5 microns the measurements revealed accordance of the measured section thickness with that adjusted on the sliding microtome. In the range surpassing 5 microns the section thickness obtained was in all cases lower than that adjusted on the microtome. The deviations were up to 40%.

[Studies of the cell cycle of experimental animal tumors following X-ray treatment]. / Zellzyklusuntersuchungen an experimentellen Tiertumoren nach Röntgenbestrahlung.

With the aim to contribute to optimized radiotherapy the proliferation kinetic parameters in experimental animal tumors were determined. As compared to non-radiated tumors, a single X-ray dose of 3 Gy accelerated the time course of the mitotic cycle which may be interpreted as a repair response. In contrary, following a single irradiation with 12 Gy the mitotic phases were delayed in their temporal course. Surprisingly, fractionated irradiations of these tumors yielded significantly less favorable results (no tumor regression, shorter rates of survival) in comparison with those after a single high X-ray dose. Obviously, this is due to a great share of hypoxic tumor cell areas in solid Ehrlich carcinomas which cannot irreversibly be impaired by low radiation doses.