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C Dahinden

Publications and source records attributed to C Dahinden.

At least 19 recordsLinked to original sources
PubMed1999

Distinct serum cytokine levels in drug- and measles-induced exanthema.

BACKGROUND: Macular or maculopapular skin reactions are frequent events in drug allergy as well as in viral infections. Clinically, the differentiation may be difficult in the absence of a clear relationship to drug intake or failure to detect virus-specific antibodies of the IgM class. Studies on drug-specific T cell lines and T cell clones isolated from drug-allergic patients have suggested that these cells may represent a significant source of IL-5. On the other hand, viral infections are frequently associated with elevated IFN-gamma levels. OBJECTIVE: Determination of serum-cytokine levels to differentiate between drug- and virally induced skin eruptions. PATIENTS: 18 patients suffering from acute drug allergy and 19 patients with acute measles, rubella or parvovirus infection. MEASUREMENTS: Cytokine-ELISA (IL-5, IL-4 and IFN-gamma) of sera collected during acute drug allergy or during acute measles, rubella or parvovirus infection. RESULTS: In 12/18 patients with drug allergy, IL-5 and/or IL-4 were elevated. A significant correlation (r(Spearman) = 0.84) between IL-5 serum levels and eosinophil counts in the blood was found. No correlation was detected between IL-4 and blood eosinophilia or between IL-4 and IL-5 levels. After remission, IL-5 and IL-4 decreased to undetectable levels. IFN-gamma on the other hand was not measurable in patients with drug allergy while elevated IFN-gamma serum levels were detected in 17/19 patients with measles, rubella or parvovirus infection; 2 patients with acute virus infection had elevated IL-5, and/or IL-4 and IFN-gamma levels. CONCLUSION: These data underline the distinct pathogenesis of these morphologically similar exanthemas and suggest that the combined analysis of eosinophilia in the blood, IL-4 and IFN-gamma might help in differentiating skin eruptions.

Adolescent↗
PubMed1998

[Effect of E. coli endotoxin on auto-/paracrine function and endothelial cell loss of donor corneas in organ culture].

Corneal cells are known to participate in the regulation of local inflammatory processes by secretion of cytokines. As the corneal endothelium may be exposed to endotoxin in organ culture and endotoxin is known to trigger inflammatory reactions, we investigated the effect of endotoxin from E. coli on organ cultured donor corneae with respect to autocrine and paracrine functions and the endothelial viability and density. 6 pairs of donor corneae were transferred to organ culture. Medium samples were taken prospectively from day 0 to day 20. On day 10 the medium was changed and one of each pair was incubated with 50 micrograms/ml of endotoxin while the other was immersed in standard organ culture medium. The samples were screened for IL-1, -2, -4, -5, -6, -8, -10, TNF alpha and GM-CSF by ELISA. In addition endothelial cell counts were performed at day 0, after 10 and after 20 days of organ culture, using the fixed frame technique. All endotoxin-incubated organ culture media showed significantly increased IL-6 and -8 levels compared to the fellow cornea and to pre-exposure levels (P < or = 0.004). In the endotoxin-treated corneae a significantly higher endothelial cell loss occurred (P = 0.007) and signs of degeneration were observed. None of the other cytokines (IL-1 alpha, IL-2, IL-4, IL-5, IL-10, GM-CSF and TNF alpha) were detected during either the first (1 to 10-day) or the second (11 to 20-day) phase of incubation. A correlation seems to exist between an increase in IL-6 and -8 induced by endotoxin, and endothelial cell loss in organ culture.

Adult↗
PubMed1997

Endotoxins modulate the autocrine function of organ cultured donor corneas and increase the incidence of endothelial cell death.

BACKGROUND/AIMS: Bacterial endotoxin is a potent inflammatory stimulator, the local and systemic responses thereby elicited being mediated via the release of cytokines from diverse cell types. Under physiological conditions, the corneal endothelium is protected from these toxins by the epithelial and vascular barriers, but in organ culture these safeguards are no longer operative, and such substances will therefore have ready access to this cell layer. The consequences of such exposure may take the form of overt damage to the endothelium and/or a more discreet influence on the cornea's immunological status, the effects of which may be realised only after transplantation, by its poor performance. The media bathing organ cultured donor corneas were monitored for the presence of various cytokine mediators of the inflammatory response before and after incubation with endotoxin, and these data compared with those pertaining to endothelial cell morphology and numerical density. METHODS: Six pairs of fellow donor corneas were cultured for an initial equilibration period of 10 days and then transferred to fresh medium; thereafter, one of each pair was incubated in the absence, and the other in the presence, of endotoxin (50 micrograms/ml = 25,000 units/ml), and culturing continued for a further 10 days. Samples of medium were withdrawn at regular intervals throughout the 20 days and screened for the cytokines IL-1, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, GM-CSF, AND TNF by ELISA; endothelial cell morphology and area density were assessed on days 0, 10, and 20. RESULTS: Spiking of organ culture media with endotoxin led to a substantial increase in the level of IL-8, and a smaller one in that of IL-6, but none of the other cytokines were detected. In five of the six stimulated corneas, these changes coincided with an increased incidence of endothelial cell loss, compared with that incurred by the fellow control, and the surviving population also evinced signs of degeneration not seen in the latter. CONCLUSION: Endotoxin induced increases in the levels of IL-6 and IL-8 appear to be correlated with endothelial cell loss. Since no adverse effects of this toxin on long term cultured monolayers of human corneal endothelial cells have been previously observed, the damage incurred in corneal organ culture may well be attributable to the influence of cytokines produced by other corneal cells or a non-intrinsic (passenger) cell population, such as macrophages, Langerhans cells or lymphocytes present under these latter conditions.

Autocrine Communication↗
PubMed1996

Severe osteoporosis due to systemic mast cell disease: successful treatment with interferon alpha-2B.

We describe a 33-year old man suffering from severe vertebral osteoporosis and urticaria pigmentosa due to systemic mast cell disease (SMCD). Because i.v. clodronate therapy could not prevent further vertebral fractures, an additional treatment with interferon alpha-2b was initiated. During 24 months of treatment, our patient had no further pain episodes, no new vertebral fractures were discovered, trabecular bone mineral density (BMD) increased significantly and urticarial symptoms improved. Nevertheless, the extent of skin lesions remained unchanged. On histological examination, a remarkable decrease of mast cells was observed in the bone marrow, but not in the skin. Five months after discontinuation of interferon alpha-2b, trabecular BMD decreased and urticarial symptoms deteriorated. These findings illustrate a beneficial effect of interferon alpha-2b on SMCD-induced osteoporosis as well as urticarial symptoms, and raise the question whether this treatment may have a diverse impact on mast cell population in different tissues.

Adult↗
PubMed1996

Influence of bee venom immunotherapy on degranulation and leukotriene generation in human blood basophils.

BACKGROUND: Rapid clinical tolerance can be induced over several hours by very fast bee venom immunotherapy (VIT) protocols. OBJECTIVE: To investigate the mechanisms underlying VIT we examined the changes of blood basophil responsiveness during VIT. METHODS: Seven bee venom allergic patients with a history of severe systemic reactions after a bee sting were investigated. A cumulative dose of 111.1 micrograms bee venom (BV) was administered sc over 3.5 h under intensive care conditions according to an ultra-rush protocol. The release of histamine and the formation of leukotrienes in response to BV, major BV allergen Phospholipase A2 (PLA), IgE receptor cross-linking with the use of monoclonal antibodies against IgE and IgE receptor, as well as IgE independent activation in response to C5a were determined in vitro before and after ultra-rush VIT. RESULTS: We demonstrated a decrease of total histamine in peripheral blood leucocytes just after VIT. Histamine release in response to all the stimuli used is not affected by ultra-rush VIT, if expressed as per cent release of total histamine. However, the absolute amount product released in response to stimulation was decreased, particularly with allergen (BV, PLA). We also found a significant reduction of LTC4 formation after VIT in samples stimulated with specific allergen (BV, PLA). CONCLUSION: Blood basophils are a target for VIT, which induces impaired release of both preformed and newly generated mediators. However, we believe the basic mechanisms of rapid clinical tolerance induced by ultra-rush VIT remain to be investigated.

Antibodies, Monoclonal↗
PubMed1995

Bee venom immunotherapy results in decrease of IL-4 and IL-5 and increase of IFN-gamma secretion in specific allergen-stimulated T cell cultures.

The mechanisms of bee venom immunotherapy (VIT) are largely unknown. The aim of this study was to follow the changes of T cell cytokine secretion during the course of VIT. Ten bee venom-allergic patients with a history of severe systemic reactions, positive skin tests, and bee venom (BV)-specific serum IgE Abs were treated as follows: on the first day, a cumulative dose of 111 micrograms, starting with 0.1 microgram, was administered s.c. under intensive care conditions. Further injections of 100 micrograms BV were given on day 7, day 21, and thereafter at intervals of 4 wk. Blood samples were obtained just before the initiation of VIT, after the last injection on the same day, and before the subsequent BV injections on days 7, 21, and 50 of VIT. Peripheral blood mononuclear cells (PBMC) were stimulated with phospholipase A (PLA), the major BV allergen, or with a control Ag tetanus toxoid (TT). Cytokine secretion was measured 24 h after restimulation of the cultures with solid-phase bound OKT3 F(ab')2 mAbs after 7 days of culture. In PLA-stimulated cultures, VIT resulted in decreased IL-4 and IL-5 and increased IFN-gamma secretion. In TT-stimulated cultures, we observed similar levels of cytokines before and during VIT. We conclude that ultra-rush VIT changes allergen-specific T cell reactivity.

Allergens↗
PubMed1993

Complement fragment C3a stimulates Ca2+ influx in neutrophils via a pertussis-toxin-sensitive G protein.

The signal pathways of neutrophils following stimulation with the complement fragment C3a (C3a) were studied in neutrophils and compared to the pathways activated by complement fragment C5a (C5a). Analysis of polyphosphoinositol lipid turnover showed that C5a, but not C3a, activated phosphatidylinositol-bisphosphate-3-kinase (PtdInsP2 3-kinase) indicating that different signal pathways are activated by the two anaphylatoxins. To examine whether C3a stimulated Ca2+ transients, cytosolic free Ca2+ levels were analyzed in Fluo-3-labelled neutrophils by flow cytometry. C3a stimulated a fast and concentration-dependent increase of cytosolic free Ca2+. Comparison of the C3a response with that of C5a revealed a more pronounced C5a-triggered Ca2+ rise. Addition of EGTA to the extracellular buffer prior to stimulation did not significantly alter the initial Ca2+ rise at low C5a concentrations, but reduced the time course of the Ca2+ transients at high concentrations. In marked contrast, EGTA completely blocked the Ca2+ response stimulated by C3a in neutrophils labeled with either Indo-1/AM or Fluo-3. Preincubation of neutrophils with pertussis toxin inhibited both C3a- and C5a-stimulated Ca2+ transients, indicating the involvement of guanine-nucleotide-binding proteins (G proteins) in these processes. In order to examine whether the C3a receptor is coupled to G proteins, binding of guanosine 5'-O-(3-[35S]thiotriphosphate) ([35S]GTP[S]) to purified neutrophil plasma membranes was studied. Both C3a and C5a stimulated high-affinity binding of [35S]GTP[S] up to 1.5-fold and 3-fold, respectively. These data suggest that the two anaphylatoxins activate pertussis-toxin-sensitive G proteins, which then trigger different signal transduction pathways. C3a specifically stimulated Ca2+ influx from the extracellular medium, whereas C5a additionally activated the PtdInsP2 3-kinase and stimulated Ca2+ mobilization from intracellular stores.

Calcium↗
PubMed1983

Granulocyte activation by endotoxin. II. Role of granulocyte adherence, aggregation, and effect of cytochalasin B, and comparison with formylated chemotactic peptide-induced stimulation.

PMN stimulation by endotoxin is heavily dependent on incubation conditions: although marked increase of PMN adhesiveness, enzyme release, and hexose monophosphate shunt activity, as well as superoxide production, occur when endotoxin-challenged cells are incubated in stationary petri dishes, absolutely no such response is observed with cells kept in suspension. Preincubation with cytochalasin B does not alter this reaction pattern. Hyperadhesiveness of endotoxin-challenged PMN is retained after thorough washing, eliminating the possibility that adhesion is due to absorption of endotoxin to petri dishes. In contrast to formylated chemotactic peptides that stimulate PMN adherence as well as aggregation, endotoxin elicits absolutely no aggregatory response (+/- cytochalasin B). Preexposure to endotoxin does not block the aggregatory response to subsequent addition of chemotactic peptides, whereas effects of endotoxin and formylated peptides on PMN in the stationary system are additive. These findings indicate that contact to surfaces is an essential primary event in PMN stimulation.

Cell Adhesion↗
PubMed1983

Granulocyte activation by endotoxin. I. Correlation between adherence and other granulocyte functions, and role of endotoxin structure on biologic activity.

Reminiscent of high concentrations of formylated chemotactic peptides, another group of bacteria-derived products, the lipopolysaccharides and lipid A, stimulate PMN adherence to petri dishes. Attachment and spreading of PMN is accompanied by intense release of secondary granule constituents and marked stimulation of the hexose monophosphate shunt activity. Dose-response studies with endotoxin preparations of diverse activity show that induction of PMN adherence, enzyme release, and respiratory burst activation are highly correlated, suggesting that this functional triad is mediated by a common mechanism. Hyperadhesiveness inducing concentrations of the chemotactically inert endotoxin lead to marked inhibition of PMN migration without affecting the direction-finding mechanism of the cell toward formylated peptides and C-derived chemotaxin(s). Endotoxin preparations at a lower grade of aggregation are more active, and the polysaccharide chains of the molecule are not essential with respect to PMN stimulation. Under our experimental conditions, endotoxin-induced stimulation of PMN is not inhibited by indomethacin, suggesting independence of cyclooxygenase-derived products. This type of PMN activation may play an important role in endotoxin-mediated tissue damage in vivo. Furthermore, hyperadhesion-induced inhibition of PMN migration to inflammatory sites during endotoxemia might hamper host resistance.

Arachidonic Acids↗
PubMed1983

Cyclic neutropenia: amplification of granulocyte oscillations by lithium and long-term suppression of cycling by plasmapheresis.

A patient with well documented cyclic neutropenia (CN) was given chronic lithium therapy as well as a short course of plasmapheresis with therapeutic intention. While on lithium therapy, an increase in the amplitude of the granulocyte oscillations was observed, but recurrent agranulocytotic periods persisted. A 2-wk course of plasmapheresis (total exchange 17 liters) resulted in a gradual decrease of granulocyte oscillations, with the granulocyte count remaining above 500/cu mm at all times, and the patient became asymptomatic. The improvements in the clinical state of the patient have now persisted for more than 9 mo. Quantitative analysis of the oscillation period and the phase lags between peak counts of the hematologic cell lines revealed a 20-day cycle for granulocytes, monocytes, reticulocytes, and platelets, but not for lymphocytes. The observed phase lags, together with the literature values for the intramarrow maturation times of the hematologic cell lines, suggest that the feedback regulation abnormality, believed to be at the basis of CN, primarily affects the stem cell that is still capable of differentiating into granulocytes and monocytes, but that the oscillations of reticulocytes and platelets are the result of a stem cell competition for uncommitted precursor cells by the primarily oscillating granulocyte and monocyte production.

Aged↗
PubMed1981

Glia cell response to bacterial lipopolysaccharide: effect on nucleotide synthesis, its genetic control and definition of the active principle.

Cell types sensitive to lipopolysaccharides (LPS) include macrophages, polymorphonuclear leukocytes, platelets, B-lymphocytes and fibroblasts. Earlier observations that during endotoxemia or intracerebral injection of LPS morphological and functional alterations of the central nervous system develop, suggest that LPS may also interact with brain cells. The effects of bacterial products on nucleotide synthesis of cultured murine glia cells are examined in this study. LPS extracted from the outer cell wall of gram-negative bacteria were found to cause an increased RNA synthesis and an inhibition of DNA synthesis in the cultured glia cells. The inhibitory effect of LPS on DNA synthesis is not due to an LPS-mediated increase of the cAMP content in the glia cells or contact inhibition of the monolayer culture. Within the structure of LPS lipid A was found to be the active part. On the basis of the LPS-induced increase of RNA synthesis, the glia cells of C3H/HeJ mice are low responders to low doses of LPS. We conclude that in the presence of fetal calf serum glia cells are sensitive to the lipid A part of LPS, the sensitivity being under genetic control.

Animals↗
PubMed1980

Receptor-directed inhibition of chemotactic factor-induced neutrophil hyperactivity by pyrazolon derivatives. Definition of a chemotactic peptide antagonist.

The two pyrazolon derivatives, phenylbutazone and sulfinpyrazone, selectively inhibit chemotactic peptide-induced effects on neutrophils. As they antagonize the induction of acute neutropenia in vivo and of cellular hyperadhesiveness, lysosomal enzyme release, hexose monophosphate shunt activity, and superoxide production in vitro, these effects occur with a specificity not shared with other prostaglandin biosynthesis inhibition by these drugs resembles the competitive type of antagonism and occurs at concentrations attainable in vivo under clinical conditions. The locomotory machinery, the direction-finding mechanisms, and the basic metabolic machinery of the cell are unaffected. These drugs interfere with specific binding of the formylpeptide to its receptor on neutrophils.

Agranulocytosis↗
PubMed1979

[Pharmacologic remobilization of hyperadhesive granulocytes: a new principle in "anti-inflammatory" therapy].

It is thought that the nonsteroidal anti-inflammatory drugs act through inhibition of cyclooxygenase (CO). The authors show that the pyrazolon derivatives phenylbutazone (P) and sulfinpyrazone (S) affect PMN function in a manner independent of CO inhibition. During inflammation PMN often show increased adhesiveness. Such adhesiveness can be provoked in vitro by high concentrations of chemotaxins. Preincubation (10--20 minutes) of platelet-free human PMN suspensions in heat-inactivated plasma with 100 micrograms P or S per ml completely abolished a submaximal adherence induction on Petri dishes from 4% adherent cells in the absence, to 23% in the presence, of 10(-7) M of the chemotaxin N-f-Met-Leu-Phe (FP). In vivo, premedication of rabbits with P or S prevented the FP-induced neutropenia, e.g. 10 mg/kg of S blocked a 5-minutes agranulocytosis. P and S also abrogated adherence-induced lysosomal enzyme release and FP-stimulated hexose monophosphate pathway (HMP) activity. FP-induced hyperadhesiveness impedes PMN locomotion. Preincubation of PMN with P or S reestablished random motility and allowed chemotactic migration toward activated C (as C5a) in spite of the presence of 'adhesive' concentrations of FP. The potent CO inhibitors indomethacin and aspirin had no effect on FP-induced adherence, enzyme release, neutropenia and HMP stimulation. In 3 selected patients with PMN hyperadhesiveness, correction of this adhesiveness by P paralleled clinical remission. It is concluded that P and S exert their antiinflammatory action at least in part by interfering with PMN hyperadhesiveness and lysosomal enzyme release. These effects are independent of the prostaglandin-thromboxane system, since other CO inhibitors are uneffective.

Cell Adhesion↗
PubMed1979

Modulating influence of chemotactic factor-induced cell adhesiveness on granulocyte function.

The importance of adhesion in regulating locomotion and accumulation of polymorphonuclear leukocytes (PMN) has remained vague. We found that the chemotaxis of human PMN resuspended in heat-inactivated plasma was maximal toward 1-10 nM N-formyl-met-leu-phe (f-Met-Leu-Phe), but fell below random motility toward >/= 100 nM. This impressive decrease of motility was paralleled by increased cell adherence on Petri dishes being minimal at 1 nM and maximal at >10 nM f-Met-Leu-Phe (6+/-1 and 37+/-2% [SE] adherent cells, respectively). Checked by phase-contrast microscopy, cells under stimulated adhesion lost the typical bipolar shape of moving PMN and became immobilized and highly flattened. PMN, preexposed to 250 nM f-Met-Leu-Phe and tested after washing, retained increased adhesiveness and showed extremely low random and chemotactic motility. In contrast, preexposure to 1 nM f-Met-Leu-Phe had no effect on chemotaxis. Supporting the concept that immobilizing hyperadhesiveness does not correspond to a general functional hyporesponsiveness of PMN, no depression of the initial ingestion rate was observed in the presence of 250 nM f-Met-Leu-Phe. Moreover, a close correlation was found between the induction of PMN adhesiveness and the stimulation of the hexose monophosphate pathway activity as well as of lysomal enzyme release (r >/= 0.98). Thus, "chemotactic deactivation" and "high-dose inhibition of chemotaxis" by N-formyl peptides is the consequence of increased cell adhesiveness. This phenomenon provides a mechanism for cell trapping at the inflammatory site. Conversely, if operative in circulating blood, e.g., in septicemia, it may impair PMN emigration to such sites.

Adult↗