Relationships between Levels of Serum IgE, Cell-Bound IgE, and IgE-Receptors on Peripheral Blood Cells in a Pediatric Population

Background: Elevated serum immunoglobulin (Ig) E is a diagnostic marker of immediate-type allergic reactions. We hypothesize that serum IgE does not necessarily reflect total body IgE because in vivo IgE can be bound to cell surface receptors such as FcεRI and FcεRII (CD23). The aim of this study was to analyze the relationships between levels of serum IgE, cell-bound IgE, and IgE-receptors on peripheral blood cells in a pediatric population. Methodology: Whole blood samples from 48 children (26 boys, 22 girls, mean age 10,3±5,4 years) were analyzed by flow cytometry for FcεRI, CD23, and cell-bound IgE on dendritic cells (CD11c+MHC class II+), monocytes (CD14+), basophils (CD123+MHC class II-) and neutrophils (myeloperoxidase+). Total serum IgE was measured by ELISA and converted into z-units to account for age-dependent normal ranges. Correlations were calculated using Spearman rank correlation test. Principal Findings: Dendritic cells, monocytes, basophils, and neutrophils expressed the high affinity IgE-receptor FcεRI. Dendritic cells and monocytes also expressed the low affinity receptor CD23. The majority of IgE-receptor positive cells carried IgE on their surface. Expression of both IgE receptors was tightly correlated with cell-bound IgE. In general, cell-bound IgE on FcεRI+ cells correlated well with serum IgE. However, some patients carried high amounts of cell-bound IgE despite low total serum IgE levels. Conclusion/Significance: In pediatric patients, levels of age-adjusted serum IgE, cell-bound IgE, and FcεRI correlate. Even in the absence of elevated levels of serum IgE, cell-bound IgE can be detected on peripheral blood cells in a subgroup of patients

Nanovesicles from Malassezia sympodialis and Host Exosomes Induce Cytokine Responses – Novel Mechanisms for Host-Microbe Interactions in Atopic Eczema

BACKGROUND: Intercellular communication can occur via the release of membrane vesicles. Exosomes are nanovesicles released from the endosomal compartment of cells. Depending on their cell of origin and their cargo they can exert different immunoregulatory functions. Recently, fungi were found to produce extracellular vesicles that can influence host-microbe interactions. The yeast Malassezia sympodialis which belongs to our normal cutaneous microbial flora elicits specific IgE- and T-cell reactivity in approximately 50% of adult patients with atopic eczema (AE). Whether exosomes or other vesicles contribute to the inflammation has not yet been investigated. OBJECTIVE: To investigate if M. sympodialis can release nanovesicles and whether they or endogenous exosomes can activate PBMC from AE patients sensitized to M. sympodialis. METHODS: Extracellular nanovesicles isolated from M. sympodialis, co-cultures of M. sympodialis and dendritic cells, and from plasma of patients with AE and healthy controls (HC) were characterised using flow cytometry, sucrose gradient centrifugation, Western blot and electron microscopy. Their ability to stimulate IL-4 and TNF-alpha responses in autologous CD14, CD34 depleted PBMC was determined using ELISPOT and ELISA, respectively. RESULTS: We show for the first time that M. sympodialis releases extracellular vesicles carrying allergen. These vesicles can induce IL-4 and TNF-α responses with a significantly higher IL-4 production in patients compared to HC. Exosomes from dendritic cell and M. sympodialis co-cultures induced IL-4 and TNF-α responses in autologous CD14, CD34 depleted PBMC of AE patients and HC while plasma exosomes induced TNF-α but not IL-4 in undepleted PBMC. CONCLUSIONS: Extracellular vesicles from M. sympodialis, dendritic cells and plasma can contribute to cytokine responses in CD14, CD34 depleted and undepleted PBMC of AE patients and HC. These novel observations have implications for understanding host-microbe interactions in the pathogenesis of AE

The RISAP-study: a complex intervention in risk communication and shared decision-making in general practice

General practitioners (GPs) and patients find it difficult to talk about risk of future disease, especially when patients have asymptomatic conditions, and treatment options are unlikely to cause immediate perceptible improvements in well-being. Further studies in risk communication training are needed. Aim:1) to systematically develop, describe and evaluate a complex intervention comprising a training programme for GPs in risk communication and shared decision-making, 2) to evaluate the effect of the training programme on real-life consultations between GPs and patients with high cholesterol levels, and 3) to evaluate patients' reactions during and after the consultations. Methods/Design The effect of the complex intervention, based around a training programme, will be evaluated in a cluster-randomised controlled trial with an intervention group and an active control group with 40 GPs and 280 patients in each group. The GPs will receive a questionnaire at baseline and after 6 months about attitudes towards risk communication and cholesterol-reducing medication. After each consultation with a participating high cholesterol-patient, the GPs will complete a questionnaire about decision satisfaction (Provider Decision Process Assessment Instrument). The patients will receive a questionnaire at baseline and after 3 and 6 months. It includes questions about adherence to chosen treatment (Morisky Compliance Scale), self-rated health (SF-12), enablement (Patient Enablement Instrument), and risk communication and decision-making effectiveness (COMRADE Scale). Prescriptions, contacts to the health services, and cholesterol level will be drawn from the registers. In each group, 12 consultations will be observed and tape-recorded. The patients from these 24 consultations will be interviewed immediately after the consultation and re-interviewed after 6 months. Eight purposefully selected GPs from the intervention group will be interviewed in a focus group 6 months after participation in the training programme. The process and context of the RISAP-study will be investigated in detail using an action research approach, in order to analyse adaptation of the intervention model to the specific context. Discussion This study aims at providing GPs and patients with a firm basis for active deliberation about preventive treatment options, with a view to optimising adherence to chosen treatment. Trial registration ClinicalTrials.gov Protocol Registration System NCT0118705

Modelling mammalian energetics: the heterothermy problem

Global climate change is expected to have strong effects on the world’s flora and fauna. As a result, there has been a recent increase in the number of meta-analyses and mechanistic models that attempt to predict potential responses of mammals to changing climates. Many models that seek to explain the effects of environmental temperatures on mammalian energetics and survival assume a constant body temperature. However, despite generally being regarded as strict homeotherms, mammals demonstrate a large degree of daily variability in body temperature, as well as the ability to reduce metabolic costs either by entering torpor, or by increasing body temperatures at high ambient temperatures. Often, changes in body temperature variability are unpredictable, and happen in response to immediate changes in resource abundance or temperature. In this review we provide an overview of variability and unpredictability found in body temperatures of extant mammals, identify potential blind spots in the current literature, and discuss options for incorporating variability into predictive mechanistic models

The Yugoslav successor states: from self-management socialism to political capitalism

This chapter argues that in some of the successor states of former Yugoslavia an economic system of political capitalism has replaced the former economic system of socialist self-management. The chapter focuses on the examples of Croatia and Serbia using a case-study approach. In the former country, the commanding heights of the economy were captured during the wars of the 1990s by new elites of returning emigres and managers without strong connections to the former communist party. In the latter the old elites were reproduced under the period of sanctions, sanctions-busting and the development of organised crime networks. Both are examples of variants of a system of political capitalism in which a ruling political elite dominates the economy, extracting quasi-rents and undermining productivity and economic growth. In contrast, in Slovenia, a form of coordinated market economy emerged from the old self-management system. It was not significantly affected by the Yugoslav conflicts and became an EU member state in 2004. These examples suggest that political capitalism is not a natural consequence of the transition from self-management, but rather a consequence mediated by the effect of war, conflict and sanctions