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C J Wiedermann

Publications and source records attributed to C J Wiedermann.

144 records · Page 8Linked to original sources
PubMed1987

High-affinity substance P binding sites in rat esophagus plexus submucosus.

Substance P receptors were investigated in rat esophagus using 125I-Bolton-Hunter substance P as a labeling probe. Autoradiographic studies show that esophageal submucosa contains clusters of high-affinity substance P binding sites [maximum binding (Bmax) 4.2 +/- 0.28 fmol/mg protein; dissociation constant (Kd) 0.1 +/- 0.01 X 10(9) M]. The receptor distribution pattern is typical for submucous neurons. These data suggest that substance P may act as a neurotransmitter in rat esophagus.

Animals↗
PubMed1986

Bombesin in human and guinea pig alveolar macrophages.

Bombesin found in neuroepithelial bodies and oat cell carcinoma of the lung, is thought to play an important role in normally developing and malignant lung. Monocytes-macrophages and human small cell lung carcinoma cells share several features, including macrophage-specific surface markers and the expression of functional receptors for bombesin-like neuropeptides and growth factors. Because small cell lung carcinoma cells synthesize immunoreactive bombesin, we investigated the possibility that alveolar macrophages also contain bombesin, a plausible hypothesis considering the many reports of neuropeptide production by immune cells and cells of bone marrow origin. Adherent human peripheral blood mononuclear cells as well as human and guinea pig alveolar macrophages were found to contain bombesin. The peptide was detected by radioimmunoassay, immunohistochemistry, high-pressure liquid chromatography with the use of different monospecific antibodies.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Chromatographic analysis of gastrin-releasing peptide in heat-inactivated fetal calf serum.

Gastrin-releasing peptide and the carboxyterminal fragments gastrin-releasing peptide [14-27] and [18-27] are found by radioimmunology and high performance liquid chromatography to be present in heat-inactivated fetal calf sera. Peptides containing the carboxyterminal sequence of gastrin-releasing peptide are known to display mitogenic activity. Thus, gastrin-releasing peptide represents a new class of mitogenic factors that are present in heat-inactivated fetal calf serum.

Animals↗
PubMed1986

Substance P receptors in rat spleen: characterization and autoradiographic distribution.

The interaction of substance P with intact lymphatic tissue was quantified and autoradiographically visualized, using slide-mounted tissue sections of rat spleen. Radiolabeled substance P binds rapidly to an apparently single class of noninteracting high affinity sites (Kd = 2.4 nmol/L; Bmax = 9.4 fmol/mg protein). The ligand selectivity pattern suggests that substance P binding sites are similar to substance P receptors found in other tissues, including the brain, T lymphocytes, and macrophages. Substance P receptors are highly concentrated in the antigen-trapping spleen marginal zone, with low densities being found in the red pulp. No specific binding of radiolabel to T cell-dependent immunologic domains of the spleen is seen. The distribution of substance P receptors suggests that substance P is probably involved in the control of sensory functions of the immune system.

Animals↗
PubMed1985

Plasma catecholamines in arterial and capillary blood.

Adrenaline and noradrenaline concentrations in arterial and simultaneously collected "arterialised" capillary plasma (vasodilated ear-lobe) obtained from unmedicated resting subjects (n = 9) were measured radio-enzymatically and found to be indistinguishable (adrenaline: 112 +/- 42 ng/l versus 109 +/- 52 ng/l; noradrenaline: 378 +/- 174 ng/l versus 410 +/- 219 ng/l; mean +/- SD; paired t-test: P greater than 0.10). The fitted regression lines did not differ significantly from the line of identity (slope = 1). The correlation coefficient was 0.969 for adrenaline and 0.945 for noradrenaline. Adrenaline and noradrenaline concentrations in plasma from freely flowing capillary blood (non-hyperaemic fingertip) were very similar to those in arterial plasma (adrenaline: 101 +/- 89 ng/l versus 90 +/- 72 ng/l;noradrenaline: 399 +/- 240 ng/l versus 395 +/- 240 ng/l; n = 13 each; paired t-test: P greater than 0.10). The correlation coefficient was 0.981 and 0.917 for adrenaline and noradrenaline, respectively. Adrenaline concentrations in capillary plasma (vasodilated earlobe), however, were significantly higher than those in venous (forearm) plasma (100 +/- 51 ng/l versus 61 +/- 23 ng/l; n = 15; P less than 0.01; capillary-venous difference = 35 +/- 18%) while noradrenaline concentrations did not differ significantly. We conclude that capillary plasma resembles arterial plasma in its catecholamine content and we show that arterial catecholamine levels may be determined in capillary, especially "arterialised" specimens, eliminating the need for arterial blood sampling.

Adult↗
PubMed1984

Biochemical and functional properties of large and small dense-core vesicles in sympathetic nerves of rat and ox vas deferens.

A comparative study of the noradrenaline storing vesicles in vas deferens from ox and rat was performed. Microsomal fractions were subjected to density gradient centrifugation. In rat, noradrenaline and dopamine beta-hydroxylase were mainly present in the upper fractions of the gradient, which is consistent with the predominance of light (small dense-core) vesicles in this species. In ox, noradrenaline, dopamine and dopamine beta-hydroxylase were found in the gradient in a bimodal distribution. This is consistent with the presence of about equal numbers of small and large dense-core vesicles in this species. On the other hand, chromogranin A, immunologically related proteins and enkephalin-like immunoreactivity were only present in the dense (large dense-core) vesicle population. In order to study the capability of light and dense vesicles to synthesize noradrenaline we "pulse-labelled" ox vasa deferentia with [3H]tyrosine. Already 3.5 min after the pulse both types of vesicles contained [3H]noradrenaline and [3H]dopamine. During longer "chase" periods the amount of [3H]dopamine gradually declined. We conclude that dense (large dense-core) vesicles contain chromogranin A, immunologically related proteins and enkephalin-like immunoreactivity whereas light (small dense-core) vesicles are devoid of these components. Both types of vesicles contain dopamine beta-hydroxylase and can synthesize noradrenaline from dopamine under in vivo conditions.

Animals↗
PubMed1983

[Significance of quantitative enzyme-cytochemical studies for hematologic cytology].

Enzyme-cytophotometrical investigations allow evaluation of enzyme activity within single, morphologically classified cells. Special problems like development of blood cells, bone marrow cells or of macrophages may thus be studied. Knowledge about the kinetics of granulopoiesis allows a better understanding of altered functional characteristics of abnormally developed blood cells. Enzyme cytochemical microdensitometry promises to be a useful tool in haematological cytology.

Acid Phosphatase↗
PubMed1983

Investigation of granulocytopoietic kinetics by microdensitometric evaluation of primary granule naphthol-AS-D-chloroacetate esterase activity.

Using a scanning microscope photometer we determined quantitatively the enzymecytochemical reaction product for naphthol-AS-D-chloroacetate esterase in neutrophilic granulocytes and their precursors in man. Evaluation of neutrophilic cells from three healthy donors resulted in a logarithm-normal distribution. After subdivision of these cells in their morphologically defined maturational stages no statistically bimodal distribution was shown within the single cell groups. Myelocytes showed twice the amount of the polymorphonuclear neutrophil absorption values. The highest promyelocyte obsorptions were double the values of the myelocyte absorptions. The standard deviation of the absorbance obtained with promyelocytes (which encompass cells already producing granules up to cells reaching their maximal granule content) was significantly higher than the standard deviation of the myelocytes. As already known, primary granules are only synthesized at the promyelocyte stage and - according to the present knowledge - their chloracylesterase and peroxidase activities are not lost during further maturation. Consequently, our results indicate that only enzyme-rich, late promyelocytes undergo mitosis transforming into myelocytes. Correspondingly, their absorption value was halved. Since the absorbance from myelocytes to polymorphonuclears is again halved, myelocytes divide only once. Metamyelocyte absorptions in part correspond to that of myelocytes. This indicates that no distinction can be made between myelocytes with mitotic capacity and "true" if only the size and the nuclear shape are considered metamyelocytes which are not longer capable of undergoing mitosis.

Adult↗
PubMed1982

[Quantitative-cytochemical evaluation of acid phosphatase activity in skin window macrophages (author's transl)].

The acid phosphatase activity (acP) of developing skin window macrophages topically treated with 6-methyl-prednisolone (6-MP) has been evaluated by a quantitative-cytochemical technique (SMP 05/PDP 12-20). The following conclusions can be drawn: 1. The degranulation of migrated monocytes can be inhibited by local application of 0.1 to 10.0 micrograms of 6-MP per skin window lesion. 2. The increase of acP-activity associated with the physiologic transformation of monocytes into macrophages and the concomitant activation of the lysosomal system was clearly inhibited by 0.05 to 10.0 micrograms per skin window lesion. 3. 6-MP alters the morphology of the developing macrophages and alters the intracellular distribution of acP. 4. It can be concluded that 6-MP inhibits the development of monocytogenic macrophages. This effect is observed with amounts of 6-MP which correspond to those obtained by systemic application of 6-MP in usual dosages. The antiphlogistic effect of 6-MP probably is due to a considerable proportion by the direct influence on the inflammatory cells.

Acid Phosphatase↗
PubMedDate not supplied

Superoxide anion release from neutrophils in growth hormone deficient adults before and after replacement therapy with recombinant human growth hormone.

The observations that growth hormone primes neutrophils and stimulates various activities of monocytes suggested that it plays a role in the regulation of leukocyte biology. The in vivo reduction of growth hormone levels may be responsible for to the functional impairment of leukocytes observed in growth hormone deficient children. Whether leukocyte function is impaired in growth hormone deficient adults is not known as yet. We therefore studied superoxide anion release from neutrophils and chemotaxis of monocytes in 15 patients with adult-onset growth hormone deficiency before and after a period of 6 months of replacement therapy with recombinant human growth hormone. Analyses were performed by comparing functions of the leukocytes from these patients with those from age and sex-matched healthy control subjects. Before growth hormone treatment, patients received appropriate replacement therapy with thyroid, adrenal and gonadal hormones. The dose of recombinant human growth hormone was 0.25-0.5 U/kg/week (0.013-0.026 mg/kg/day) throughout the whole period of replacement therapy. In growth hormone deficient subjects, formylpeptide-triggered release of superoxide anions from neutrophils was significantly suppressed by about 40% before treatment as compared to healthy control subjects. After 6 months of replacement therapy, neutrophil superoxide anion release was similar in patients and healthy individuals. Neither before nor after replacement therapy, however, was there a difference in monocyte migration between control and growth hormone deficient subjects. These data indicate that neutrophil function is somehow altered in growth hormone deficient patients, even when receiving appropriate therapy with thyroid, adrenal and gonadal hormones, but that neutrophil function can be restored to near normalcy by growth hormone replacement therapy. This would suggest that suppressed neutrophil respiratory burst is due to the deficiency in growth hormone.

Adult↗
PubMedDate not supplied

Autoradiographic analysis of binding sites for 125I-Bolton-Hunter-substance P in the human eye.

Substance P is known to exert potent effects in peripheral tissues, and is thought to be important for ocular function. The mechanism of action of substance P in the human eye is not known. As a basis for biochemical characterization specific binding of 125I-Bolton-Hunter-substance P was demonstrated in the human eye using autoradiographic methods. Biochemical characterization on slide-mounted tissue preparations showed that binding was saturable with a KD of 0.27 +/- 0.1 nmol/l. Specific binding occurred at comparable autoradiographic densities to both human retina and choroid. Substance P and its carboxyterminal fragment, substance P(3-11), were shown to be highly potent in binding competition experiments against 125I-Bolton-Hunter-substance P. Similar concentrations of substance P(1-9), neurokinin A and neurokinin B failed to significantly alter specific binding of 125I-Bolton-Hunter-substance P. The results indicate expression of high affinity substance P binding sites in human retina and choroid.

Autoradiography↗
PubMedDate not supplied

Visualization of cholecystokinin receptors on a subset of human monocytes and in rat spleen.

Direct radioreceptor binding experiments and Scatchard analysis reveal CCK receptors on elutriator purified human peripheral blood monocytes, but not on purified human T cells. The monocyte receptors have a single class of high (0.1 nM) affinity binding sites. A structure-function analysis of monocyte binding by different CCK analogs correlates well with previously demonstrated chemotactic responses in monocytes and receptors in brain tissue. Biochemical cross-linking indicates that the monocyte CCK recognition molecule is comparable in molecular size to that in brain membranes. Utilizing a novel fluoresceinated Texas Red-CCK conjugate we have visualized that up to 20% of human peripheral monocytes bear receptors for CCK. A discrete and anatomically significant distribution of CCK receptors in rat spleen is shown by film autoradiography of tissue sections. A more detailed microscopic analysis identifies a dendritic population of monocyte-derived cells within the periarteriolar lymphocyte sheath (PALS) of the white pulp as the CCK receptor-bearing cell in spleen. The anatomical localization of receptor-bearing cells within the PALS region suggests a role for CCK in the antigen processing and sensitization phases of the immune response via regulatory effects of this peptide on a specific, local macrophage-related cell population.

Amino Acid Sequence↗
PubMedDate not supplied

Influence of neuropeptides on neutrophil adhesion and transmigration through a lung fibroblast barrier in vitro.

The lung is richly supplied with peptidergic nerves that store and secrete substance P (SP), vasoactive intestinal peptide (VIP), and other neuropeptides known to potently modulate leukocyte function in vitro and airway inflammation in vivo. We examined the effect of SP, VIP and the novel sensory neuropeptide secretoneurin (SN), as well as of interleukin (IL)-8, IL-6, IL-1 beta, transforming growth factor (TGF)-beta, and tumor necrosis factor (TNF), all associated with acute lung injury, on human neutrophil migration across a 5-mu pore polycarbonate filter system covered by human lung fibroblast monolayers. Additionally, we tested the ability of these neuropeptides to elicit neutrophil adhesion to fibroblast monolayers. SP, but not VIP and SN, may be important in directly influencing neutrophil adhesion to and subsequent migration across a subendothelial barrier of fibroblasts and extracellular matrix towards lung inflammatory sites. The effect was mainly mediated by neurokinin (NK)-1 receptors, as evaluated by a specific NK-1 antagonist, [[(S,S)Pro-Leu(spiro-y-lactam)]9,10, Trp11]substance P (1-11), whereas a specific NK-2 receptor antagonist, [Tyr5, D-Trp6,8,9, Lys10]neurokinin A (4-10), was ineffective. The SP analog septide and the NK-1 receptor agonist ([Sar9 Met(O2)11)SP were comparably effective. Furthermore, the SP effect was concentration and time dependent. However, the other tested neuropeptides might also affect neutrophil recruitment in inflammatory lung by modulating other lung cell functions. Additionally, all tested cytokines stimulated neutrophil transfibroblast migration in vitro, except IL-6. In conclusion, SP in concert with proinflammatory cytokines may regulate neutrophil interstitial accumulation and their traffic to the alveolar space in lung inflammation.

Cell Adhesion↗
PubMedDate not supplied

CD40 ligand-dependent maturation of human monocyte-derived dendritic cells by activated platelets.

Atherosclerosis is defined as an inflammatory immunological disease that is triggered by platelet activation, endothelial injury and consequent innate and adaptive immune processes. Dendritic cells are critical for the cell-mediated arm of the immune response as they activate naïve T cells after maturation. Platelets play a crucial role in thrombus formation in the injured vessel walls. We investigated the role of resting and thrombin-activated platelets in dendritic cell maturation in vitro using platelets and monocyte-derived dendritic cells from healthy donors. Resting platelet supernatants did not affect maturation, whereas supernatants from thrombin-activated platelets induced dendritic cell maturation as demonstrated by FACS analysis of HLA-DR expression. This effect was inhibited by anti CD40 ligand antibody, but not by aspirin pretreatment of platelets. Supernatants of platelet-dendritic cell co-cultures induced augmented monocyte migration when platelets were activated by thrombin, again reversible by blocking CD40 ligand. These data show that activated platelets trigger dendritic cell maturation independent of cyclooxygenase-derived arachidonic acid metabolites by mechanisms involving CD40 ligand, which is also involved in monocyte chemotactic mediator release from platelets and dendritic cells. The results of this study suggest a role of CD40 ligand from activated platelets in connecting innate and adaptive immunity.

Blood Platelets↗
PubMedDate not supplied

Attenuation of leukocyte beta 2-integrin expression by antithrombin-III.

Antithrombin-III exerts antiinflammatory effects via ligation of heparan sulfate proteoglycans. Here we show in vitro that recombinant human antithrombin-III attenuates CD11b/CD18 expression of activated neutrophils and monocytes in whole blood ex vivo. As leukocyte integrin expression is triggered by extracorporeal circulation, this observation may be of relevance for pharmacological treatment during cardiopulmonary bypass.

Adult↗
PubMedDate not supplied

Regulation of myeloid phagocyte development and function by growth hormone: a review.

Growth hormone (GH) has previously been implicated in T cell development and function, and here we review its efficacy in promoting development and function of myeloid cells. Evidence obtained from both in vitro and in vivo studies suggests that, in animals as well as in man, GH augments proliferation and differentiation of erythroid, megakaryocytic and myeloid progenitor cells. Mechanisms of hemopoietic actions probably involve induction of insulin-like growth factor-1, which is under GH control. Effects are mostly, though not exclusively, seen in GH deficiency states. Like other hemopoietic factors currently undergoing clinical trials for modulation of mature phagocyte function, GH is found in vitro and in vivo to stimulate potently monocyte migration and to prime neutrophils and macrophages for enhanced activation by second stimuli. Activation of neutrophils is mediated by GH action on the neutrophil prolactin receptors. The detailed mechanism of macrophage activation is currently unknown. GH action on myeloid phagocytes may help to explain protective effects of GH observed in experimental infection as well as its promotive effect on wound healing.

Animals↗
PubMedDate not supplied

Decrease of respiratory burst in neutrophils of patients with ankylosing spondylitis by combined radon-hyperthermia treatment.

OBJECTIVE: To define the respiratory burst activity of neutrophils, the total anti-oxidative status of plasma, and the parameters of systemic inflammation in patients with ankylosing spondylitis (AS) before and after a combined radon-hyperthermia treatment in the thermal tunnels of Böckstein-Bad Gastein in Austria. METHODS: In 20 patients with AS the effects of a total of 15 hours of radon-hyperthermia-treatment spread over a period of three weeks were studied. The respiratory burst activity of neutrophils was measured fluorometrically using dichlorofluorescein diacetate, the total anti-oxidant status was measured using azinodiethyl-benzthiazoline-sulphonate, and inflammation parameters were determined by routine laboratory assays. RESULTS: Before treatment, the basal neutrophil respiratory burst in patients (n = 20) was 409 +/- 62 fluorescence arbitrary units (AU; mean +/- SEM) and 359 +/- 37 AU in controls (n = 9; p > 0.5); the stimulated respiratory burst (fMet-Leu-Phe, 10(-6) M) was 1,027 +/- 133 AU in patients and 1,152 +/- 218 AU in controls (p > 0.5). After treatment, the basal neutrophil respiratory burst in patients (n = 19) was 137 +/- 16 and in controls it was 174 +/- 35 AU (n = 8; p > 0.1); the stimulated respiratory burst was 670 +/- 66 and 1,305 +/- 82 AU, in patients and controls respectively (p < 0.001). No effects of treatment on the total anti-oxidant status of the plasma or on the parameters of inflammation were detected. CONCLUSION: Combined radon-hyperthermia treatment reduces the respiratory burst activity of the blood circulating neutrophils in patients with AS. If respiratory burst activity from the neutrophils plays a role in the pathophysiology of ankylosing spondylitis, the observed reduction may be related to the beneficial effects of radon-hyperthermia treatment.

Adult↗