Biomedical subjects

N Meissner

Publications and source records attributed to N Meissner.

6 recordsLinked to original sources

PubMed1999

Modified T-cell activation pattern during specific immunotherapy (SIT) in cat-allergic patients.

OBJECTIVE: The aim of the study was to analyse early effects of specific immunotherapy (SIT) on immune functions in cat-allergic patients. METHODS: Immunological responses of peripheral blood mononuclear cells from eight cat-allergic patients were analysed before and after SIT in comparison with 11 nonallergic controls. Cells were stimulated in vitro with either bacterial superantigen, mitogen, or cat allergen. Production of IL-12 and TH1/TH2 cytokines was analysed by ELISA and lymphocyte subset distribution was assessed by flow-cytometry. RESULTS: We found a significantly reduced secretion of IL-12 (P < 0.05) from cells of allergic individuals compared with the controls. This finding was associated with significantly lower IFN-gamma production after stimulation with allergen (P < 0.05) that did not increase during SIT. However, no significant differences were seen after stimulation with mitogen indicating an allergen specific IFN-gamma secretion response in allergic individuals. Prior to SIT IL-5 production was significantly higher in cells of allergic donors stimulated with allergen < 0.005 or mitogen (< 0.05). After reaching the maintenance dose for SIT, allergen-induced IL-5 production returned to normal levels, whereas it remained elevated after stimulation with mitogen. These changes were associated with a reduced frequency of CD45 RO T cells following SIT. CONCLUSION: These results suggest that SIT exerts early effects on allergen-specific T-cell responses with selective inhibition of the up-regulated TH2 immune response.

Allergens↗

PubMed1999

Combination of von Willebrand disease type 1 and partial factor XII deficiency in children: clinical evidence for a diminished bleeding tendency.

Factor XII deficiency can be associated with a thrombotic and VWF deficiency with a haemorrhagic clinical course. To study the potential influence of factor XII deficiency on bleeding tendency in patients suffering from VWD we retrospectively compared the clinical outcome of children with either an isolated factor XII deficiency, an isolated VWD, or a combination of both. Patients with the combined coagulation defect showed significantly fewer bleeding events when compared to patients with isolated VWD, although ristocetin cofactor activities were reduced to a comparable degree. As far as aPTT values are concerned, there were no significant differences among the three groups. Whether this combination of thrombophilic and haemorrhagic coagulation disorders is only coincidental or the result of an active modulation of one of the two counteracting coagulation factors is not known at present.

Adolescent↗

PubMed1997

A subset of CD8+ T cells from allergic patients produce IL-4 and stimulate IgE production in vitro.

BACKGROUND AND OBJECTIVE: A subset of IL-4 producing CD8+ T cells was recently identified in HIV patients. Based on these findings we examined whether IL-4 producing CD8+ T cells would also be present in allergic patients and what would be the functional relevance of this T-cell population. METHODS: We investigated the role of CD8+ T cells in IgE production of allergic diseases by analysing the cytokine profile of individual CD4+ and CD8+ T cells. RESULTS: In allergic patients about twice as many CD4+ T cells and six times as many CD8+ T cells produced IL-4 as in non-allergic controls. In contrast the frequency of IFNgamma+ T-cell subsets did not significantly differ between the allergic and non-allergic individuals. The frequency of IL4+ CD8+ T cells correlated with the level of serum IgE. Coculture experiments with T cells or purified CD8+ T cells together with autologous B cells indicated that CD8+ T cells enhanced IgE in vitro, but not IgM production, even when they were physically separated from B cells. This effect could be partially blocked by addition of an IL-4 binding protein, a soluble IL-4 receptor indicating that IL-4 is involved in CD8+ T-cell mediated IgE production. CONCLUSIONS: These data indicate a positive role of IL-4 secreting CD8+ T cells in IgE regulation in allergic patients.

Adult↗

PubMed1995

Relevance of mediators to cardiac parameters of isolated anaphylactic guinea-pig heart.

The release of histamine, eicosanoids and catecholamines were measured after induction of anaphylaxis in isolated guinea-pig hearts. The concentration-time profile of these mediators was compared with changes of cardiac parameters. The histamine and catecholamine levels of the coronary effluent were determined at 10 s intervals; thromboxane and prostacyclin levels at 60 s intervals. The release of histamine and norepinephrine were maximum between 20 and 30 s after the antigen challenge and decreased rapidly within 60 s. Thromboxane and prostacyclin increased to a maximum after 3 min and declined slowly within 10 min. The rise in histamine release was correlated with tachycardia. The release of thromboxane was correlated with the increase of coronary perfusion pressure. Cimetidine inhibited the tachycardia and clemastine reduced bradyarrhythmia. The inhibition of lipoxygenase and cyclooxygenase also reduced the rise in the perfusion pressure. These data suggest that different mediators are time-dependently involved in anaphylaxis-induced cardiac changes.

6-Ketoprostaglandin F1 alpha↗

PubMed1995

Role and modulation of T-cell cytokines in allergy.

Allergic sensitization and the development of effector functions are controlled by IL-4-secreting and IL-5-secreting type 2 T cells. Recent studies have provided new insights into the events triggering the development of type 1 and type 2 T cells, the discrimination of type 1 and type 2 effector T cells from various T-cell subsets, and the improvement of established and new therapeutic strategies, which are aimed at modulating such T-cell functions in the allergic patient.

Adjuvants, Immunologic↗

PubMedDate not supplied

Granulomatous cheilitis and Crohn's disease in a 3-year-old boy.

Granulomatous cheilitis and Crohn's disease are disorders of unknown etiology. There are case reports describing their coincidence and pointing out the necessity of ruling out systemic disorders once the diagnosis of granulomatous cheilitis is made. However, such reports are few and the causal association of both diseases is controversial in the literature. We report the youngest patient so far, a 3-year-old boy, who had granulomatous cheilitis and Crohn's disease simultaneously. This coincidence so early in life strongly suggests that both represent manifestations of the same disease.

Anti-Infective Agents↗