Serum levels of folate, 25-hydroxyvitamin D3 and cobalamin during UVB phototherapy: findings in a large prospective trial.

BACKGROUND: Narrowband UVB phototherapy (NB-UVB) is a mainstay in the treatment of numerous inflammatory dermatoses. Whereas, a wealth of studies has shown that NB-UVB treatment increases 25-hydroxyvitamin D3 (25(OH)D) levels, only sparse and controversial data exist on its effect on serum folate and cobalamin. OBJECTIVES: To determine whether exposure to NB-UVB alters serum folate or cobalamin levels. METHODS: A single-centre, prospective, open observational study on 101 patients subjected to NB-UVB phototherapy between late fall and early spring. Serum folate, 25(OH)D and cobalamin levels were measured after 0, 12, 24 and 36 NB-UVB exposures. RESULTS: After 12 NB-UVB exposures a significant decrease of mean serum folate (-1.0 nmol/L; P = 0.03) and cobalamin (-14.5 pmol/L, P = 0.03) levels was observed whereas serum levels of 25(OH)D showed a significant increase (35.4 nmol/L, P < 0.0001). CONCLUSIONS: A standard course of NB-UVB induces a small but significant decrease of serum folate and cobalamin levels.

The conformational IgE epitope profile of soya bean allergen Gly m 4.

BACKGROUND: Birch pollen-related soya allergy is mediated by Gly m 4. Conformational IgE epitopes of Gly m 4 are unknown. OBJECTIVE: To identify the IgE epitope profile of Gly m 4 in subjects with birch pollen-related soya allergy utilizing an epitope library presented by Gly m 4-type model proteins. METHODS: Sera from patients with (n = 26) and without (n = 19) allergy to soya as determined by oral provocation tests were studied. Specific IgE (Bet v 1/Gly m 4) was determined by ImmunoCAP. A library of 59 non-allergenic Gly m 4-type model proteins harbouring individual and multiple putative epitopes for IgE was tested in IgE binding assays. Primary, secondary and tertiary protein structures were assessed by mass spectrometry, circular dichroism and nuclear magnetic resonance spectroscopy. RESULTS: All subjects were sensitized to Gly m 4 and Bet v 1. Allergen-specific serum IgE levels ranged from 0.94 to > 100 kUA /L. The avidities of serum IgE were 5.06 ng (allergic) and 1.8 ng (tolerant) as determined by EC50 for IgE binding to Gly m 4. 96% (46/48) of the protein variants bound IgE. Model proteins had Gly m 4-type conformation and individual IgE binding clustered in six major surface areas. Gly m 4-specific IgE binding could be inhibited to up to 80% by model proteins harbouring individual IgE binding sites in an epitope-wise equimolar fashion. Receiver operating curve analysis revealed an area under fitted curve of up to 0.88 for model proteins and 0.66 for Gly m 4. CONCLUSION AND CLINICAL RELEVANCE: Serum levels and avidity of Gly m 4-specific IgE do not correlate with clinical reactivity to soya. Six IgE-binding areas, represented by 23 amino acids, account for more than 80% of total IgE binding capacity of Gly m 4. Model proteins may be used for epitope-resolved diagnosis to differentiate birch-soya allergy from clinical tolerance.

Effect of a phytogenic feed additive on the susceptibility of Onchorhynchus mykiss to Aeromonas salmonicida.

In recent years, feed additives have increasingly been adopted by the aquaculture industry. These supplements not only offer an alternative to antibiotics but have also been linked to enhanced growth performance. However, the literature is still limited and provides contradictory information on their effectiveness. This is mainly due to the wide variety of available products and their complex mechanisms of action. Phytogenic feed additives have been shown to have antimicrobial effects and can improve growth performance. In the present study, we investigated the susceptibility of several fish pathogenic bacteria to a phytogenic essential oil product in vitro. In addition, we determined the protective effect of a commercial phytogenic feed additive containing oregano, anis and citrus oils on the resistance of rainbow trout Oncorhynchus mykiss to infection by Aeromonas salmonicida. The bacterium was administered through 3 different routes: intra-peritoneal injection, immersion in a bacterial solution and cohabitation with infected fish. Mortality rates were significantly lower in infected rainbow trout that had received the feed additive: the overall mortality rate across all routes of infection was 18% in fish fed a diet containing the additive compared to 37% in fish that received unsupplemented feed. The route of infection also significantly impacted mortality, with average mortality rates of 60, 17.5 and 5% for intra-peritoneal injection, immersion and cohabitation, respectively. In general, fish were better protected against infection by immersion than infection by injection.

Neuroimaging and neuromodulation approaches to study eating behavior and prevent and treat eating disorders and obesity.

Functional, molecular and genetic neuroimaging has highlighted the existence of brain anomalies and neural vulnerability factors related to obesity and eating disorders such as binge eating or anorexia nervosa. In particular, decreased basal metabolism in the prefrontal cortex and striatum as well as dopaminergic alterations have been described in obese subjects, in parallel with increased activation of reward brain areas in response to palatable food cues. Elevated reward region responsivity may trigger food craving and predict future weight gain. This opens the way to prevention studies using functional and molecular neuroimaging to perform early diagnostics and to phenotype subjects at risk by exploring different neurobehavioral dimensions of the food choices and motivation processes. In the first part of this review, advantages and limitations of neuroimaging techniques, such as functional magnetic resonance imaging (fMRI), positron emission tomography (PET), single photon emission computed tomography (SPECT), pharmacogenetic fMRI and functional near-infrared spectroscopy (fNIRS) will be discussed in the context of recent work dealing with eating behavior, with a particular focus on obesity. In the second part of the review, non-invasive strategies to modulate food-related brain processes and functions will be presented. At the leading edge of non-invasive brain-based technologies is real-time fMRI (rtfMRI) neurofeedback, which is a powerful tool to better understand the complexity of human brain-behavior relationships. rtfMRI, alone or when combined with other techniques and tools such as EEG and cognitive therapy, could be used to alter neural plasticity and learned behavior to optimize and/or restore healthy cognition and eating behavior. Other promising non-invasive neuromodulation approaches being explored are repetitive transcranial magnetic stimulation (rTMS) and transcranial direct-current stimulation (tDCS). Converging evidence points at the value of these non-invasive neuromodulation strategies to study basic mechanisms underlying eating behavior and to treat its disorders. Both of these approaches will be compared in light of recent work in this field, while addressing technical and practical questions. The third part of this review will be dedicated to invasive neuromodulation strategies, such as vagus nerve stimulation (VNS) and deep brain stimulation (DBS). In combination with neuroimaging approaches, these techniques are promising experimental tools to unravel the intricate relationships between homeostatic and hedonic brain circuits. Their potential as additional therapeutic tools to combat pharmacorefractory morbid obesity or acute eating disorders will be discussed, in terms of technical challenges, applicability and ethics. In a general discussion, we will put the brain at the core of fundamental research, prevention and therapy in the context of obesity and eating disorders. First, we will discuss the possibility to identify new biological markers of brain functions. Second, we will highlight the potential of neuroimaging and neuromodulation in individualized medicine. Third, we will introduce the ethical questions that are concomitant to the emergence of new neuromodulation therapies.

IgE recognition patterns in peanut allergy are age dependent: perspectives of the EuroPrevall study.

BACKGROUND: We tested the hypothesis that specific molecular sensitization patterns correlate with the clinical data/manifestation in a European peanut-allergic population characterized under a common protocol. METHODS: Sixty-eight peanut-allergic subjects and 82 tolerant controls from 11 European countries were included. Allergy to peanut and lowest symptom-eliciting dose was established by double-blind placebo-controlled food challenge in all but anaphylactic subjects. Information of early or late (before or after 14 years of age) onset of peanut allergy was obtained from standardized questionnaires. IgE to peanut allergens rAra h 1-3, 6, 8-9, profilin and CCD was determined using ImmunoCAP. RESULTS: Seventy-eight percent of peanut allergics were sensitized to peanut extract and 90% to at least one peanut component. rAra h 2 was the sole major allergen for the peanut-allergic population. Geographical differences were observed for rAra h 8 and rAra h 9, which were major allergens for central/western and southern Europeans, respectively. Sensitization to rAra h 1 and 2 was exclusively observed in early-onset peanut allergy. Peanut-tolerant subjects were frequently sensitized to rAra h 8 or 9 but not to storage proteins. Sensitization to Ara h 2 ≥ 1.0 kUA /l conferred a 97% probability for a systemic reaction (P = 0.0002). Logistic regression revealed a significant influence of peanut extract sensitization and region on the occurrence of systemic reactions (P = 0.0185 and P = 0.0436, respectively). CONCLUSION: Sensitization to Ara h 1, 2 and 3 is usually acquired in childhood. IgE to Ara h 2 ≥ 1.0 kUA /l is significantly associated with the development of systemic reactions to peanut.

A controlled trial on the effect of feeding dietary chestnut extract and glycerol monolaurate on liver function in newborn calves.

Beginning in the fall of 2010, an increasing and alarming number of cases of calves suffering from liver dystrophy were reported in the south of Germany. An epidemiological investigation was carried out by the authors between November 2010 and July 2011, leading to the implication of a commercial dietary supplement as the potential cause for this outbreak. The components of this product were first tested in a cell culture model and two of them (dietary chestnut extract and glycerol monolaurate) showed a cytotoxic effect. The objective of this study was therefore to evaluate the effect of supplemental feeding of both components alone or in combination on liver function in newborn calves on a commercial dairy farm. Ten calves were enrolled in each of the three treatment groups and the control group (group O) following a blocked design. Treatment consisted of supplementation with chestnut extract at 0.02% of birth body mass (BM) (group C), supplementation with glycerol monolaurate at 0.006% of BM (group G) or a combined treatment (group CG) for five consecutive days. The effect of treatments on liver function was evaluated clinically and by measurement of glutamate dehydrogenase (GLDH) and aspartate aminotransferase (AST) activities as well as the determination of the concentrations of glucose, L-lactate and total bilirubin in serum. There was a significant increase in GLDH and AST activities and a significant decrease in glucose concentration in treatment groups C and CG compared with the control group (p ≤ 0.035), whereas no difference was shown for group G. Survival was significantly decreased in groups C (p = 0.029) and CG (p = 0.001) compared with both group G and the control group. These results suggest that dietary chestnut extract in an amount of 0.02% of BM alone or in combination has a toxic effect on liver function in newborn calves.

Dietary probiotic supplementation modulated gut microbiota and improved growth of juvenile rainbow trout (Oncorhynchus mykiss).

In aquaculture, infectious diseases are the major cause of economic losses. Probiotic supplementation may change the microbiota of the digestive tract and modulate the immune defences and nutritional performance. This study was conducted to evaluate the dietary supplementation of multi-species (A: Bacillus sp., Pediococcus sp., Enterococcus sp., Lactobacillus sp.) and single-species probiotics (B: Pediococcus acidilactici) on growth performance and gut microbiota of rainbow trout (Oncorhynchus mykiss). A basal diet was supplemented with probiotic A or B, at two concentrations each (A1, A2, B1 and B2) or not supplemented (control treatment). Diets were distributed to 30 groups of 20 fish, 3 times a day. The gut microbiota was analysed at the end of the feeding trial (96 days) with 16S rDNA denaturing gradient gel electrophoresis (16S-DGGE). Changes in gut microbial community were assessed by Shannon index (H´) and number of operational taxonomic units (OTUs). After 56 days of feeding, weight gain was significantly improved in fish fed diet A1 when compared to the control group. Dietary probiotic supplementation changed the gut microbial composition. Number of OTUs (R) was higher in fish fed A1 (multi-species at lower concentration) than in control group, while H´ was higher in fish fed A1, B1 and B2.

Airborne olive pollen counts are not representative of exposure to the major olive allergen Ole e 1.

Pollen is routinely monitored, but it is unknown whether pollen counts represent allergen exposure. We therefore simultaneously determined olive pollen and Ole e 1 in ambient air in Córdoba, Spain, and Évora, Portugal, using Hirst-type traps for pollen and high-volume cascade impactors for allergen. Pollen from different days released 12-fold different amounts of Ole e 1 per pollen (both locations P < 0.001). Average allergen release from pollen (pollen potency) was much higher in Córdoba (3.9 pg Ole e 1/pollen) than in Évora (0.8 pg Ole e 1/pollen, P = 0.004). Indeed, yearly olive pollen counts in Córdoba were 2.4 times higher than in Évora, but Ole e 1 concentrations were 7.6 times higher. When modeling the origin of the pollen, >40% of Ole e 1 exposure in Évora was explained by high-potency pollen originating from the south of Spain. Thus, olive pollen can vary substantially in allergen release, even though they are morphologically identical.

[High incidence of jaundice in young calves in Southern Germany]. / Häufung von Ikterus bei jungen Kälbern in Süddeutschland.

OBJECTIVE: Between September, 2010, and August, 2011, a series of cases of jaundice of unknown origin in young calves was detected in a number of farms in Southern Germany. This paper describes the syndrome on the basis of 57 cases, and the approach taken to discover the cause. MATERIAL AND METHODS: The clinical course of the disease is described in 19 patients. Using a case definition (calves aged 1-3 weeks, total serum bilirubin > 20 µmol/l and/or serum glutamate dehydrogenase [GLDH] activity >50U/l and/or autopsy findings with striking liver pathology [jaundice, liver dystrophy, cirrhosis]), 36 farms were included in an epidemiological survey. In a feeding trial, two batches of a dietary supplement feed, previously used in diseased calves on farms, were fed at the dosage recommendations of the manufacturer to four clinically healthy calves over 5days. Four other calves served as controls. The calves were clinically monitored daily, and blood samples were investigated using clinical chemistry and haematology. RESULTS: Clinical examination revealed behavioural alterations (weakness, tonic-clonic seizures and bawling just before death), recumbency, jaundice and discolouration of faeces. In less severe cases without clinical signs, there was an increase in serum bilirubin concentration and/or GLDH activity. In the epidemiological survey of affected farms, the feeding of a diet supplement feed was registered in 54 of 57 cases. The feeding of two batches of that diet supplement feed to four clinically healthy calves resulted in a significant (p<0.05) increase in bilirubin and lactate concentrations, as well as the GLDH activity in serum, but without serious impairment of the general condition, whereas in control calves, no comparable changes were observed. CONCLUSION: The results of the epidemiological survey and the feeding trial suggest a causal involvement of a dietary supplement feed. The toxic principle is unknown. CLINICAL RELEVANCE: Knowledge of the clinical picture and the probable feed-related context is important to detect this disease early. The suspected dietary supplement feed has been taken off the market, but with other products similar problems may arise.

Component-resolved in vitro diagnosis of carrot allergy in three different regions of Europe.

BACKGROUND: Carrot is a frequent cause of food allergy in Europe. The objective of this study was to evaluate a panel of carrot allergens for diagnosis of carrot allergy in Spain, Switzerland and Denmark. METHODS: Forty-nine carrot allergic patients, 71 pollen allergic but carrot-tolerant patients and 63 nonatopic controls were included. Serum IgE to carrot extract, recombinant carrot allergens (rDau c 1.0104; rDau c 1.0201; rDau c 4; the isoflavone reductase-like proteins rDau c IFR 1, rDau c IFR 2; the carrot cyclophilin rDau c Cyc) were analyzed by ImmunoCAP. RESULTS: The sensitivity of the carrot extract-based test was 82%. Use of the recombinant allergens increased the sensitivity to 90%. The Dau c 1 isoforms were major allergens for Swiss and Danish carrot allergic patients, the profilin rDau c 4 for the Spanish patients. The rDau c IFR 1 and rDau c IFR 2 were recognized by 6% and 20% of the carrot allergics, but did not contribute to a further increase of sensitivity. Among pollen allergic controls, 34% had IgE to carrot extract, 18% to each of rDau c 1.0104, rDau c 1.0201 and rDau c 4, 8% to rDau c IFR 1 and 7% to rDau c IFR 2. Sensitization to rDau c Cyc occurred in one carrot allergic patient and one nonatopic control. CONCLUSION: Component-resolved in vitro analyses revealed a significant difference in IgE sensitization pattern between geographical regions and in the prevalence of sensitization to carrot components between carrot allergic and carrot-tolerant but pollen sensitized patients.

Establishment of recombinant major allergens Bet v 1 and Phl p 5a as Ph. Eur. reference standards and validation of ELISA methods for their measurement. Results from feasibility studies.

The potency of allergen extracts is determined as total allergenic activity without consideration of their composition and the units differ from one manufacturer to another, making it very difficult to compare the different products. Recently, purified major allergens have been obtained by recombinant DNA technology and produced under Good Manufacturing Practice (GMP) conditions. In principle, such recombinant allergens could be established as reference standards and could help for the standardisation of the major allergen content of allergen extracts. Two recombinant major allergens, one from birch pollen, rBet v 1, and one from Timothy grass pollen, Phl p 5a, have been selected at the end of the CREATE programme as a potential starting point for the establishment as European Pharmacopoeia (Ph. Eur.) Reference Standards through a project run by the Biological Standardisation Programme (BSP) of the European Directorate for the Quality of Medicines & HealthCare (EDQM). To this end, bulk candidate recombinant materials, produced under GMP conditions, were procured from two European manufacturers and subsequently formulated and lyophilised. Four ELISA systems from three different manufacturers were included in the project, two for Bet v 1 and two for Phl p 5a with the aim of establishing reference methods for determination of the respective major antigens both in natural allergen extracts as well as in recombinant allergen products. The project was run in 3 phases: a preparatory and preliminary testing phase (feasibility phase or Phase 1), an extended feasibility phase carried out in 3 laboratories (Phase 2) to confirm the transferability of the methods and an international collaborative study with a large number of participating laboratories (Phase 3). This article describes the work done in Phase 1 and Phase 2, i.e. the physico-chemical and biological characterisation of the recombinant candidate reference standards, the assessment of their suitability for the intended purpose as well as the evaluation of the candidate ELISA systems. The results show that both candidate reference standards are suitable for the intended purpose. In addition, three out of the four ELISA systems that were included in the preliminary phase were found to be appropriate for further evaluation in the collaborative study which was organised in 2011. The results of the collaborative study will be published separately.

Resistance to Alternaria solani in hybrids between a Solanum tuberosum haploid and S. raphanifolium.

Early blight of potato (Solanum tuberosum), caused by the foliar fungal pathogen Alternaria solani, is a major cause of economic loss in many potato-growing regions. Genetic resistance offers an opportunity to decrease fungicide usage while maintaining yield and quality. In this study, an early blight resistant clone of the diploid wild species S. raphanifolium was crossed as a male to a haploid (2n=2x) of cultivated potato. Hybrids were backcrossed to both parents. Eight families were created and evaluated for early blight resistance in the field. Families created by backcrossing to the wild species parent exhibited significantly lower relative area under the disease progress curve means than those from backcrossing to the cultivated parent, leading to the conclusion that S. raphanifolium contributes genes for early blight resistance. The mechanism of resistance in S. raphanifolium is unique because A. solani could not be recovered from lesions. Clones were identified with high levels of resistance and adaptation to the photoperiod of a temperate production region.

Mindfulness-based cognitive therapy for bipolar disorder: a feasibility trial.

BACKGROUND: The present open study investigates the feasibility of Mindfulness-based cognitive therapy (MBCT) in groups solely composed of bipolar patients of various subtypes. MBCT has been mostly evaluated with remitted unipolar depressed patients and little is known about this treatment in bipolar disorder. METHODS: Bipolar outpatients (type I, II and NOS) were included and evaluated for depressive and hypomanic symptoms, as well as mindfulness skills before and after MBCT. Patients' expectations before the program, perceived benefit after completion and frequency of mindfulness practice were also recorded. RESULTS: Of 23 included patients, 15 attended at least four MBCT sessions. Most participants reported having durably, moderately to very much benefited from the program, although mindfulness practice decreased over time. Whereas no significant increase of mindfulness skills was detected during the trial, change of mindfulness skills was significantly associated with change of depressive symptoms between pre- and post-MBCT assessments. CONCLUSIONS: MBCT is feasible and well perceived among bipolar patients. Larger and randomized controlled studies are required to further evaluate its efficacy, in particular regarding depressive and (hypo)manic relapse prevention. The mediating role of mindfulness on clinical outcome needs further examination and efforts should be provided to enhance the persistence of meditation practice with time.

The BDNF Val66Met polymorphism impacts parahippocampal and amygdala volume in healthy humans: incremental support for a genetic risk factor for depression.

BACKGROUND: The role of the brain-derived neurotrophic factor (BDNF) in the pathogenesis of affective disorders such as depression has been controversial. Mounting evidence comes from structural imaging, that the functional BDNF Val66Met polymorphism influences the hippocampal volume with carriers of the 66Met allele (Val/Met and Met/Met group) having smaller hippocampi. Given that stress-induced atrophy of the hippocampus is associated with the pathogenesis of affective disorders, the functional BDNF Val66Met polymorphism could be an incremental risk factor. METHOD: Eighty-seven healthy Caucasian participants underwent structural imaging and were genotyped for the BDNF Val66Met polymorphism. Data were analysed by means of voxel-based morphometry (VBM). RESULTS: Region of interest (ROI) analyses revealed an association between the 66Met allele and smaller parahippocampal volumes and a smaller right amygdala. In addition, the whole-brain analysis showed that the thalamus, fusiformus gyrus and several parts of the frontal gyrus were smaller in 66Met allele carriers. CONCLUSIONS: This study demonstrates that the impact of the BDNF Val66Met polymorphism is not confined to the hippocampus but also extends to the parahippocampal gyrus and the amygdala.

Clinical effects of immunotherapy with genetically modified recombinant birch pollen Bet v 1 derivatives.

BACKGROUND: Birch pollen and pollen from related trees of the Fagales order are a major cause of allergic rhinitis, conjunctivitis, and asthma through the spring season in northern and central Europe. OBJECTIVE: To investigate the clinical effects of injection immunotherapy with genetically modified derivatives of major birch pollen allergen Bet v 1 on pollen-induced allergic symptoms. METHODS: A three-arm double-blind placebo-controlled immunotherapy study was conducted with one pre-seasonal course of treatment using two derivatives of Bet v 1, namely a recombinant Bet v 1 trimer and an equimolar mixture of two recombinant Bet v 1 fragments together representing the whole protein sequence. Analysis of local and systemic adverse events was performed for 124 patients who had received at least one dose of medication. Clinical efficacy was monitored by symptom medication scores and interval scoring in the per protocol-treated population (n=84). In addition, skin and nasal provocation responses and allergen-specific antibodies were assessed. RESULTS: There were trends towards improvement in the subjects' well-being and clinical symptoms (nasal scores), although comparisons with a placebo group did not show statistical significance in the main end-point, the combined symptom medication score. Reductions in skin and nasal sensitivity were observed for some subjects with a trend for the Bet v 1 trimer to be more effective than the fragments. Treatment induced strong IgG1 and IgG4 allergen-specific antibody responses. Local injection-site reactions were most frequent in the trimer group affecting 59.5% of patients as opposed to 37.8% and 30.6% in the fragment and placebo groups, respectively. Systemic reactions were elicited more frequently by fragments. A large proportion of adverse side-effects appeared hours following injections, and might be attributable to concurrent exposure to related pollens. CONCLUSION: Single courses of injection immunotherapy with Bet v 1 allergen derivatives showed trends towards improved well-being and reduced reactivity to specific allergen provocation, but did not yield significant improvement in the combined symptom medication score in this study.

Characterization of a hypoallergenic recombinant Bet v 1 variant as a candidate for allergen-specific immunotherapy.

BACKGROUND: Recombinant allergens and especially their hypoallergenic variants are promising candidates for a more effective and safer specific immunotherapy. METHODS: Physicochemical and immunological characteristics of a folding variant of recombinant Bet v 1 (rBet v 1-FV) were investigated in comparison to natural Bet v 1 (nBet v 1) and the correctly folded recombinant Bet v 1 (rBet v 1-WT) by SDS-PAGE, size exclusion chromatography, multi-angle light scattering, circular dichroism, immunoblotting and enzyme allergosorbent test inhibition assay for detection of IgE reactivity and ELISA with Bet v 1-specific monoclonal antibodies. The functional IgE reactivity of the different Bet v 1 proteins was investigated using basophil activation in terms of CD203c expression and histamine release. T cell reactivity was investigated using T cell lines raised from birch pollen-allergic subjects against nBet v 1. Immunogenicity was investigated in mice. RESULTS: Physicochemical characterization revealed purity, homogeneity and monomeric properties of rBet v 1-FV. Unlike nBet v 1 and rBet v 1-WT, rBet v 1-FV showed almost no IgE binding in immunoblots. The reduction of allergenicity was further proved by IgE-binding inhibition assays, basophil activation and histamine release. T cell reactivity was completely conserved, as demonstrated by proliferation of Bet v 1-specific T cell lines with multiple epitope specificities. rBet v 1-FV showed strong immunogenicity in mice. CONCLUSIONS: Due to its reduced IgE reactivity and decreased capacity to activate basophils, but retained T cell reactivity and strong immunogenicity, rBet v 1-FV proved to be a very promising candidate for specific immunotherapy in birch pollen-allergic subjects.

Strategy for allergenicity assessment of 'natural novel foods': clinical and molecular investigation of exotic vegetables (water spinach, hyacinth bean and Ethiopian eggplant).

BACKGROUND: Foods not commonly consumed in the European Union must be proven safe before being brought to market, including an assessment of allergenicity. We present a three-stepwise strategy for allergenicity assessment of natural novel foods using three novel vegetables, namely, water spinach, hyacinth bean, Ethiopian eggplant. METHODS: First, vegetable extracts were analyzed for the presence of pan-allergens [Bet v 1 homologous proteins, profilins, nonspecific lipid transfer proteins (LTP)] by immunoblot analysis with specific animal antibodies. Secondly, the IgE-binding of the food extracts was investigated by EAST (Enzyme-allergosorbent test) and immunoblot analysis using sera with IgE-reactivity to known pan-allergens or to phylogenetically related foods from subjects (i) allergic to birch, grass and mugwort pollen, (ii) with food allergy to soy, peanut, tomato, multiple pollen-related foods and (iii) sensitized to LTP. Thirdly, the clinical relevance of IgE-binding was assessed in vivo by skin prick testing (SPT) and open oral food challenges (OFC). RESULTS: Profilin and LTP were detected by animal antibodies in all vegetables, a Bet v 1 homologue selectively in hyacinth bean. IgE-binding to LTP, profilin and a Bet v 1 homologue was proven by immunoblot analysis and EAST. Positive SPT and OFC results were observed for all vegetables in pollen-allergic patients. CONCLUSIONS: Our stepwise procedure confirmed the presence and IgE-binding capacity of novel vegetable proteins homologous to known allergens in endemic vegetable foods. In vivo testing proved the potential of the novel vegetables to elicit clinical allergy. Hence, our described algorithm seems to be applicable for allergenicity testing of natural novel foods.

Enhancement of hazelnut extract for IgE testing by recombinant allergen spiking.

BACKGROUND: Hazelnuts are a common cause of food allergic reactions. Most hazelnut allergic individuals in central and northern Europe are sensitized to Cor a 1, a member of the PR-10 protein family, while the lipid transfer protein Cor a 8 acts as a major allergen in the south of Europe. Other allergens, including profilin and seed storage proteins, may be important in subgroups of patients. Reliable detection of specific IgE in the clinical diagnosis of food allergy requires allergen reagents with a sufficient representation of all relevant allergen components. Some reported observations suggest that natural hazelnut extract may not be fully adequate in this respect. METHODS: The capacity of immobilized natural hazelnut extract to bind Cor a 1-, Cor a 2- and Cor a 8-specific IgE and IgG antibodies was investigated by serum adsorption and extract dilution experiments and by the use of allergen specific rabbit antisera. All measurements were performed with the ImmunoCAP assay platform. RESULTS: The experimental results revealed an incomplete capacity of immobilized hazelnut extract to capture IgE antibodies directed to the major allergen Cor a 1. Spiking of hazelnut extract with recombinant Cor a 1.04 prior to solid phase coupling gave rise to significantly enhanced IgE antibody binding from Cor a 1 reactive sera. The spiking did not negatively affect the measurement of IgE to extract components other than Cor a 1. CONCLUSION: A hazelnut allergen reagent with enhanced IgE detection capacity can be generated by supplementing the natural food extract with recombinant Cor a 1.04.

Performance and preference for ACE stimulation rates obtained with nucleus RP 8 and freedom system.

Cochlear recently released the Nucleus Freedom System which has been based on the Nucleus Research Platform 8. Both systems make use of the same implant, the CI24RE, which includes expanded total stimulation rates up to 32 kHz. In this study the performance of the ACE strategy at 500, 1200 and 3500 pps/channel was investigated using an ABC-CBA design. At the end of each period speech tests were performed. In the CBA phase the patients completed a comparative questionnaire to determine the subjective rate preference. Preliminary results in 13 recipients indicate no differences in for the ACE strategy at rates ranging from 500 pps to 3500 pps/channel.

Generation of a low immunoglobulin E-binding mutant of the timothy grass pollen major allergen Phl p 5a.

BACKGROUND: Immunotherapy of grass pollen allergy is currently based on the administration of pollen extracts containing natural allergens. Specifically designed recombinant allergens with reduced IgE reactivity could be used in safer and more efficacious future therapy concepts. OBJECTIVES: This study aimed to generate hypoallergenic variants of the timothy grass major allergen Phl p 5a as candidates for allergen-specific immunotherapy. METHODS: Three deletion mutants were produced in Escherichia coli and subsequently purified. The overall IgE-binding capacity of the mutants was compared with the recombinant wild-type allergen by membrane blot and IgE-inhibition assays. The capacity for effector cell activation was determined in basophil activation assays. T cell proliferation assays with allergen-specific T cell lines were performed to confirm the retention of T cell reactivity. Structural properties were characterized by circular dichroism analysis and homogeneity by native isoelectric focusing. The deletion sites were mapped on homology models comprising the N- and C-terminal halves of Phl p 5a, respectively. RESULTS: The double-deletion mutant rPhl p 5a Delta(94-113, 175-198) showed strongly diminished IgE binding in membrane blot and IgE-inhibition assays. Both deletions affect predominantly alpha-helical regions located in the N- and C-terminal halves of Phl p 5a, respectively. Whereas deletion of Delta175-198 alone was sufficient to cause a large reduction of the IgE reactivity in a subgroup of allergic sera, only the combination of both deletions was highly effective for all the sera tested. rPhl p 5a Delta(94-113, 175-198) consistently showed at least an 11.5-fold reduced capacity to activate basophils compared with the recombinant wild-type molecule, and the T cell proliferation assays demonstrated retention of T cell reactivity. CONCLUSION: The mutant rPhl p 5a Delta(94-113, 175-198) fulfils the basic requirements for a hypoallergenic molecule suitable for a future immunotherapy of grass pollen allergy; it offers substantially reduced IgE binding and maintained T cell reactivity.