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B C Adelmann-Grill

Publications and source records attributed to B C Adelmann-Grill.

At least 37 records · Page 2Linked to original sources

Chemotactic migration of normal dermal fibroblasts towards epidermal growth factor and its modulation by platelet-derived growth factor and transforming growth factor-beta.

During the repair phase of wound healing, fibroblasts migrate to the site of injury where they proliferate and synthesize constituents of the extracellular matrix of connective tissue. Their activity is regulated by mediators originating from cells of the blood clotting and inflammatory stage such as platelet-derived growth factor, epidermal growth factor, transforming growth factor-beta and other cytokines. This communication shows that chemotactic migration of normal dermal fibroblasts is elicited by epidermal growth factor in vitro and that platelet-derived growth factor and transforming growth factor-beta can down-regulate this activity. This suggests that in vivo these growth factors are part of an intricate network which connects and coordinates proliferation, protein synthesis and chemotactic migration of fibroblasts.

Cell Movement↗

Enzymatic collagen degradation in the pregnant guinea pig cervix during physiological maturation of the cervix and after local application of prostaglandins.

The role of enzymatic collagen degradation in prostaglandin-induced and physiological cervical ripening was studied in guinea pigs. The cervices were removed from (a) 8 non-pregnant guinea pigs, (b) 8 animals at day 45 of pregnancy, (c) 14 pregnant animals of comparable gestational age which had either an intracervical application of 0.2 ml 5% tylose or 10 micrograms sulprostone gel, and (d) 8 guinea pigs at day 63 to 65 of pregnancy. Collagenase activity was assayed in a highly specific and sensitive system using native collagen type I as substrate. Protease activity was measured by the method of Green and Shaw. Collagen fragments were identified by SDS-polyacrylamide electrophoresis (SDS-PAGE) of acetic-soluble fractions. Collagenase and protease activities were found in all extracts from the different groups. However, there were no differences in enzymatic activities between the non-pregnant, early-pregnant and late-pregnant cervical specimens. Prostaglandin pre-treatment of the cervix led to no significant increase in either collagenase or protease activity as compared to the control groups. The absence of typical collagen degradation products in the SDS-PAGE suggested that no significant collagen breakdown had taken place. In contrast to previously published literature, we conclude that enzymatic collagen degradation is unlikely to be a key factor in prostaglandin-induced and physiological cervical ripening.

Animals↗

Involvement of protein kinase C in signal transduction during fibroblast chemotaxis to platelet-derived growth factor and a fragment of fibronectin.

The involvement of protein kinase C in chemotaxis of normal dermal fibroblasts to a mitogenic and a non-mitogenic attractant was investigated. Neomycin, an inhibitor of phosphoinositide metabolism, H7, staurosporine, and sphingosine, inhibitors of protein kinase C, as well as amiloride, an inhibitor of the Na+/H+-antiport, all abrogated chemotaxis of fibroblasts to platelet-derived growth factor and to a chemotactically active fragment of fibronectin. Down-regulation of protein kinase C by phorbol ester likewise diminished the capacity of fibroblasts to move directionally to these attractants. Therefore, all three of these signal transduction steps are required for the chemotactic response of this type of cells.

Cells, Cultured↗

Collagenase activity in cervical tissue of the non-pregnant and pregnant human cervix.

Collagen degradation has been suggested to play an important role in the process of cervical ripening at term. After giving informed consent tissue samples were taken from the posterior lip of 10 non-pregnant women of child-bearing age, 10 women having a termination of pregnancy at 9-12 weeks' gestation and 12 women who had had normal spontaneous deliveries at term. Collagenase activity was measured by a specific technique using native, triple helical collagen. Proteolytic activity was determined with commercially available 14C-methaemoglobin as substrate. For identification of collagen fragments SDS-polyacrylamid-gel-electrophoresis was performed using a modified Laemmli-technique. Collagenase and protease activity were found in all extracts of the different groups. There was a marked increase in enzymatic activities in the postpartum tissue samples suggesting that significant collagen breakdown had taken place. The absence of typical collagen fragments in the SDS-electrophoresis seemed to be due to a very rapid further degradation of the fragments by proteases into small peptides which then readily left the cervix. The present findings confirm the essential role of proteolytic enzymes in cervical dilatation at term.

Adult↗

Inhibition of fibroblast chemotaxis by recombinant human interferon gamma and interferon alpha.

Interferons have recently been recognized as potent mediators in inflammatory processes, exerting profound effects on fibroblasts. The influence of interferons gamma and alpha on the chemotactic movement of fibroblasts toward various attractants was, therefore, investigated. Normal human adult and embryonal dermal fibroblasts, fibrosarcoma-derived fibroblasts and SV40-transformed fibroblasts were tested against conditioned medium from fibroblasts, the chemotactic peptide C-140 of fibronectin, platelet-derived growth factor, and leukotriene B4 as attractants in the presence or absence of the interferons. Interferons gamma and alpha inhibited chemotaxis in a dose-dependent manner and at concentrations at least as low as 10(-2) ng/ml. Inhibition was noticeable when the cells were exposed to interferon for as short a period as 60 minutes, and the effect was not readily reversible. Inhibition occurred when the cells came from sparse or dense cultures, but when platelet-derived growth factor was the attractant and the cells had been grown at low density there was no inhibition. It is concluded that this is a specific effect, not to be wholly explained by overall increase in membrane rigidity. Inhibition of fibroblast chemotaxis by interferons may be an important regulatory mechanism during wound healing or fibrosis and metastatic spread of tumor cells.

Adult↗

Collagen degradation in the pregnant human cervix at term and after prostaglandin-induced cervical ripening.

The role of enzymatic collagen degradation in prostaglandin-induced and physiological cervical ripening was studied by determining collagenase and other proteolytic activity in extracts of cervical biopsies. Collagenase activity was assayed in a highly specific and sensitive system using native collagen type I as substrate. The intracervical application of sulprostone gel prior to termination of 1st trimester pregnancy led to a marked improvement in cervical dilatability. Collagenase and proteolytic activity were found to be significantly higher in postpartum samples than in specimens obtained from the nonpregnant or early pregnant cervix. After sulprostone treatment enzymatic activities were only marginally elevated. Analysis of extractable peptides showed that sub partu collagen was degraded in preference to noncollagenous proteins into very small fragments, whereas in the process of prostaglandin-induced cervical ripening collagen degradation appears to be of minor importance.

Cervix Uteri↗

The role of collagenases and proteases in prostaglandin-induced cervical ripening.

Tissue samples were taken from the posterior lip of the cervix of 10 non-pregnant women, 10 women having a termination of pregnancy at 9-12 weeks' gestation and 16 women having a termination who had had an intracervical application of either 50 micrograms sulprostone gel or 2 ml 5% tylose 8-12 hours previously. The efficacy of cervical priming was demonstrated objectively by tonometric measurements. Collagenase activity was determined by a new highly specific technique using native, triple helical collagen. Protease activity was measured by a modified Anson-test. For identification of collagen fragments SDS-polyacrylamide electrophoresis was done on the acetic acid soluble fractions. The sulprostone gel induced effective cervical ripening in all of the patients. Collagenase and protease activity were found in all extracts from the different groups, however, PG-pretreatment of the cervix led to no significant increase in enzymatic activities. In addition, the absence of typical collagen cleavage products in the SDS-electrophoresis suggested that no significant collagen breakdown had occurred. In contrast to previously published literature we conclude that enzymatic collagen degradation does not play a predominant role in PG-induced cervical ripening.

Abortifacient Agents, Nonsteroidal↗

Follicular fluid contents as predictors of success of in-vitro fertilization-embryo transfer.

In order to establish criteria for selection of the best ova in in-vitro fertilization-embryo transfer (IVF-ET) programes we have examined the follicular fluid (FF) levels of plasminogen activator (PA), collagenolytic activity, progesterone (P) and alpha 2 macroglobulin (alpha 2M) and related them to the success of pregnancy. PA activity was similar in FF of pregnant and nonpregnant cycles, 13.8 +/- 3.9 mU/ml versus 14.6 +/- 2.9 (mean +/- SEM) respectively. By contrast, FF from pregnant cycles exhibited lower collagenolytic activity (49.6 +/- 3.9% versus 67.9 +/- 3.0; P less than 0.001). Likewise, in a semi-quantitative assay of alpha 2M, only 18.4% of the aspirates from pregnant cycles showed a precipitation line, whereas 76.8% of those from non-pregnant cycles were positive. Levels of P in aspirates from pregnant cycles were in the intermediate range, as compared with those from non-pregnant cycles (0.06-5.5 micrograms/ml versus 0.02-12.0 micrograms/ml). All these assays can be completed before ET and performed in IVF-ET programmes. In conclusion, it seems that a combination of follicular alpha 2M levels and collagenolytic activity, and to a lesser extent addition of P assay, may serve as good criteria for selecting the best embryos for establishment of pregnancy.

Cleavage Stage, Ovum↗

Inhibition of fibroblast chemotaxis by superoxide dismutase.

Superoxide radicals are known to be important mediators in chronic inflammatory and fibrotic processes, in which accumulation of fibroblasts is thought to play a major role in the pathogenetic events. The enzyme superoxide dismutase removes these radicals by a catalytic reaction. Chemotactic response of human fibroblasts and fibrosarcoma-derived cells (HT-1080) to fibroblast conditioned medium, fibronectin and platelet-derived growth factor was inhibited in a dose-dependent manner in the presence of superoxide dismutase, while random migration, cell proliferation, cell viability and synthesis of collagen and non-collagenous proteins was not altered. In contrast, phorbol myristate acetate, an inducer of superoxide generation, stimulated the chemotactic movement of fibroblasts to the attractants. Evidence for the formation of superoxide is provided by the reduction of tetrazolium salt by activated fibroblasts which could be inhibited by superoxide dismutase. Thus, it is concluded that superoxide in small amounts is involved in the mechanism of fibroblast chemotaxis. Superoxide dismutase may, therefore, reduce fibroblast migration into sites of injury or inflammation.

Catalase↗

Immunological safety evaluation of a haemostatic agent and wound dressing made of horse collagen fibrils.

A haemostatic agent and wound dressing made of horse collagen (Tachotop) was applied to guinea-pigs in such a way that the intended use of this material in humans was simulated, and cell-mediated and humoral immune responses of the animals were investigated. In addition, immune reactions were forcefully induced in guinea-pigs in order to validate the methodical approach and quantitate the observed reactions. Cell-mediated immunity was measured as delayed-type hypersensitivity skin reactions, and antibodies were detected by an enzyme-linked immunosorbent assay (ELISA). Simulation of the intended application of this haemostyptic material did not induce immune reactions in guinea-pigs even under critical conditions. The animals could only be immunized when the antigen was administered in solution or finely dispersed and together with adjuvant. Immune reactions thus induced were specific for collagen, no reaction was obtained against possible impurities such as albumin, immunoglobulin or fibronectin. It is concluded--in accordance with clinical experience--that this material is very unlikely to induce immune reactions upon clinical application to humans.

Animals↗

Collagenolytic cleavage products of collagen type I as chemoattractants for human dermal fibroblasts.

The chemoattractive properties of collagen in native (triple-helical) and denatured (random coil) conformation were compared in a Boyden chamber type assay to those of collagen fragments derived from cleavage with mammalian or bacterial collagenase using human embryonic dermal fibroblasts as target cells. Chemotaxis to native collagen required low collagen concentrations because fibril formation at high concentrations and at physiological pH and ionic strength prevented chemoattractiveness. Chemotaxis of denatured collagen was comparable to that of native collagen in solution. Cleavage of native collagen with mammalian collagenase increased, digestion with bacterial collagenase abolished its chemotactic activity. It is thought that these data may reflect the in vivo situation during inflammation and wound repair.

Cells, Cultured↗

Lung involvement in scleroderma.

Lung involvement (LI) was studied by lung function (LF) in 101 scleroderma patients (circumscribed scleroderma, n = 17; progressive systemic scleroderma [PSS], n = 84; with the subtypes I, acroscleroderma [n = 19]; 2, proximal ascending scleroderma [n = 61]; 3, trunk scleroderma [n = 4]). Eighteen percent of morphea, 32 percent of type 1, 56 percent of type 2, and 75 percent of type 3 patients had impaired LF. The LI was more frequent (57 percent vs 45 percent) and more severe (20 percent vs 3 percent) in PSS with systemic inflammation (form A) compared to those without (form B). Elevated lymphocytes/neutrophils in bronchoalveolar lavage (BAL) were found associated with form A and severe LI. The LF of patients showing an inflammatory cell pattern in initial BAL (n = 3) worsened, whereas those with normal BAL findings (n = 4) did not. Collagenase activity in BAL was significantly elevated in those with elevated lymphocytes/neutrophils in lavage. Patients with type 2 or 3 of PSS, especially form A, carry a higher risk of developing severe LI than circumscribed scleroderma, type 1, or form B patients. Differential cell count and collagenase activity in BAL is correlated with active disease and provides prognostic information.

Adolescent↗

Cryptogenic fibrosing alveolitis: prediction of fibrogenic activity from immunohistochemical studies of collagen types in lung biopsy specimens.

Collagen immunofluorescence studies were performed on biopsy specimens from 25 patients with cryptogenic fibrosing alveolitis. We studied the relationship of these results to the clinical, radiological, and physiological assessments of disease activity during six-month periods before and after the lung biopsy; to the appearances on routine histological examination; to the inflammatory cell proportions in bronchoalveolar lavage fluid; and to the response to treatment. Positive associations were observed between the presence of type III collagen and disease activity before (p less than 0.015) and after (p less than 0.02) lung biopsy. These were independent of clinical and routine histological features. The type-III-positive group also contained nine of the 11 responding to treatment. None of the type-III-positive patients had a quiescent or stable course. In contrast, most patients with no type-III-collagen fluorescence had a stable course over the time of this study and did not improve on treatment. It is suggested that collagen typing may be an additional useful method of assessing potentially reversible disease in cryptogenic fibrosing alveolitis.

Adult↗

[Mammalian collagenases: physiological and pathophysiological aspects].

Biochemical and cell biological aspects of synthesis, activation and action of mammalian collagenases are presented and discussed with respect to collagen resorption under normal and pathological conditions. Particularly emphasized are the regulatory mechanisms involved which operate at the level of synthesis of the proenzyme, during activation of the latent enzyme, and by the presence of inhibitors of the active collagenase as well as by substrate specificity for the various collagen types.

Animals↗

Independence of reciprocal attachment sites on denatured collagen and fibronectin from antigenic sites, and binding of gelatin-based plasma substitutes to plasma fibronectin.

Fibronectin and denatured collagen possess attachment sites for each other and, in addition, antigenic sites reacting with the respective antibodies. Using an enzyme linked immunosorbent assay it was shown that attachment sites and antigenic sites on fibronectin and on collagen reacted independently of each other. Gelatin-based plasma substitutes blocked the binding of fibronectin to denatured collagen thus showing that attachment sites for fibronectin are preserved in the gelatin preparations used for manufacturing these plasma substitutes. Antigenic sites, in contrast, were destroyed during the manufacturing process as shown with antibodies to denatured collagen raised in guinea-pigs. It is concluded that complex formation of gelatin-based plasma substitutes with plasma fibronectin may occur upon infusion of such plasma substitutes but that formation of antigen/antibody complexes in vivo is unlikely.

Animals↗

Immunohistochemical study of collagen types in human foetal lung and fibrotic lung disease.

Highly purified type-specific anti-collagen antibodies (prepared in animals to types I, II, III, and IV bovine collagen) were used in an indirect immunofluorescence method for the study of human lung collagen. The tissue localisation of each collagen type, and the apparent type I:III collagen ratio was assessed in normal foetal and adult lung and in fibrotic lung lesions. In the latter, the relationship of the findings to the natural history of the lesion was considered. This method was compared with routine connective tissue stains. The following observations were made. (1) Foetal lung in the canalicular phase of development proved a useful substrate for validating and standardizing the procedure. (2) Collagen fluorescence was more sensitive than connective tissue stains in detecting collagen in foetal tissues and sites of early fibrosis. (3) On the basis of collagen-type fluorescence, two distinctive patterns of fibrosis were recognised. Areas of mature collagen surrounding vessels and bronchi and in established scar tissue, for example in asbestotic pleural plaques, were virtually exclusively type I collagen. By contrast, areas of early active fibrosis like sarcoid nodules and organising pneumonia, which usually contained variable numbers of fibroblasts and chronic inflammatory cells, were characterised by an increased proportion of type III collagen and a greater intensity of both types I and III collagen fluorescence. The possible significance of this change in type III:I collagen ratio is discussed. Determination of the stage of fibrotic lesions by this method might have applications in the prediction of disease progression, and influence management of some conditions.

Adult↗

[Morphologic and biochemical aspects of prostaglandin-induced cervix ripening].

For examination by electron microscopy tissue samples were taken from the posterior lip of the cervix of 8 patients having a termination of pregnancy at 9-12th week gestation and 16 patients of comparable gestational age who had an intracervical application of either 2 ml 5% tylose or 50 micrograms sulprostone-tylose gel 8 hours before biopsy. The efficacy of cervical priming was demonstrated objectively by tonometric studies. In addition, collagenase and protease activities were determined in the cervical tissue extracts of the different treatment groups. For identification of typical collagen fragments SDS-polyacrylamide-gel-electrophoresis were carried out on the acetic acid soluble extracts. The local application of sulprostone gel induced a marked multifocal loosening of the collagenous framework; there was no evidence for leucocyte infiltration or necrosis caused by the prostaglandin (PG) pretreatment. In the areas of disorganized collagen fibres cervical fibroblasts seemed to be activated characterized by fine granular loosening of the cytoplasma, dilated cisternae of rough endoplasmatic reticulum, vacuolized enlarged mitochondria and an increased number of cytoplasmatic vesicles close to the cell surface. Collagenase and protease activities were found in all extracts of the different treatment groups, however, PG-application led to no significant increase in enzymatic activities. There was no evidence for the presence of typical collagen cleavage products in the SDS-electrophoresis. Contradictory to the hitherto published literature enzymatic collagen degradation does not play an essential role in PG-induced cervical ripening.

Abortifacient Agents↗