Perilla frutescens leaf extract inhibits mite major allergen Der p 2-induced gene expression of pro-allergic and pro-inflammatory cytokines in human bronchial epithelial cell BEAS-2B.

Perilla frutescens has been used in traditional medicine for respiratory diseases due to its anti-bacterial and anti-inflammatory activity. This study aimed to investigate effects of Perilla frutescens leaf extract (PFE) on expression of pro-allergic and pro-inflammatory cytokines in airway epithelial cells exposed to mite major allergen Der p 2 (DP2) and the underlying mechanisms. Our results showed that PFE up to 100 µg/mL had no cytotoxic effect on human bronchial epithelial cell BEAS-2B. Further investigations revealed that PFE dose-dependently diminished mRNA expression of pro-allergic cytokine IL-4, IL-5, IL-13 and GM-CSF, as well as pro-inflammatory cytokine IL-6, IL-8 and MCP-1 in BEAS-2B cells treated with DP2. In parallel to mRNA, the DP-2-elevated levels of the tested cytokines were decreased. Further investigation showed that DP2-indued phosphorylation of p38 MAPK (P38) and JNK, but not Erk1/2, was also suppressed by PFE. In addition, PFE elevated cytosolic IκBα level and decreased nuclear NF-κB level in DP2-stimulated BEAS-2B cells. Taken together, these findings revealed that PFE significantly diminished both mRNA expression and protein levels of pro-allergic and pro-inflammatory cytokines in response to DP2 through inhibition of P38/JNK and NK-κB activation. These findings suggest that PFE should be beneficial to alleviate both allergic and inflammatory responses on airway epithelium in response to aeroallergens.

Can volatile organic metabolites be used to simultaneously assess microbial and mite contamination level in cereal grains and coffee beans?

A novel approach based on headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-ToFMS) was developed for the simultaneous screening of microbial and mite contamination level in cereals and coffee beans. The proposed approach emerges as a powerful tool for the rapid assessment of the microbial contamination level (ca. 70 min versus ca. 72 to 120 h for bacteria and fungi, respectively, using conventional plate counts), and mite contamination (ca. 70 min versus ca. 24 h). A full-factorial design was performed for optimization of the SPME experimental parameters. The methodology was applied to three types of rice (rough, brown, and white rice), oat, wheat, and green and roasted coffee beans. Simultaneously, microbiological analysis of the samples (total aerobic microorganisms, moulds, and yeasts) was performed by conventional plate counts. A set of 54 volatile markers was selected among all the compounds detected by GC×GC-ToFMS. Principal Component Analysis (PCA) was applied in order to establish a relationship between potential volatile markers and the level of microbial contamination. Methylbenzene, 3-octanone, 2-nonanone, 2-methyl-3-pentanol, 1-octen-3-ol, and 2-hexanone were associated to samples with higher microbial contamination level, especially in rough rice. Moreover, oat exhibited a high GC peak area of 2-hydroxy-6-methylbenzaldehyde, a sexual and alarm pheromone for adult mites, which in the other matrices appeared as a trace component. The number of mites detected in oat grains was correlated to the GC peak area of the pheromone. The HS-SPME/GC×GC-ToFMS methodology can be regarded as the basis for the development of a rapid and versatile method that can be applied in industry to the simultaneous assessment the level of microbiological contamination and for detection of mites in cereals grains and coffee beans.

Fluorescent labeling of disulfide proteins on 2D gel for screening allergens: a preliminary study.

An experimental protocol was established to detect disulfide proteins as fluorescent spots on 2D gel. In summary, free sulfhydryl groups in a protein mixture were capped with nonfluorescent iodoacetamide, followed by chemical reduction of disulfide bonds, and labeling of newly exposed sulfhydryl groups with the fluorescent probe, monobromobimane. Disulfide proteins were detectable as fluorescent spots under the UV lamp. As accumulating evidence suggests that disulfide bonds are responsible for the allergenicity of many proteins, we sought to use this protocol to find new allergens. In a model experiment using soybean trypsin inhibitor, a well-known allergen with disulfide bonds, and myoglobin, which has a free sulfhydryl group, only the former was labeled with fluorescence. Application of the protocol to mite and pollen extracts facilitated detection of known allergens or putative allergens exhibiting sequence similarities to known allergens. In this note, we report the protocol as a complementary tool for screening allergens, which is now solely dependent on immunological recognition.

Effectiveness of specific immunotherapy in the treatment of asthma: a meta-analysis of prospective, randomized, double-blind, placebo-controlled studies.

BACKGROUND: Despite decades of positive experience with specific immunotherapy (SIT) in the treatment of asthma, outcomes associated with SIT have not been evaluated. OBJECTIVE: This meta-analysis was conducted to compare the effects of SIT plus medical treatment with those of SIT without medical treatment in patients with asthma. METHODS: All studies of SIT in patients with asthma published in English between the years 1966 and 1998 were identified through a MEDLINE search. All prospective, randomized, double-blind, placebo-controlled studies of SIT identified by the search were included in the meta-analysis. One author (R.N.R.) extracted data from these studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a random-effects model. RESULTS: Data were extracted from 24 identified studies of the clinical effectiveness of SIT in the treatment of asthma, involving 962 asthmatic patients with documented allergy. Immunotherapy was judged effective in 17 (71%) of the 24 studies, ineffective in 4 (17%), and equivocal in 3 (12%) (chi2 = 15.25, df = 2, P = 0.0005). Symptoms of asthma were more likely to improve in patients who received SIT than in patients who received placebo (OR 2.76, 95% CI 2.22 to 3.42). Results also favored the immunotherapy group for improvement in pulmonary function (OR 2.87, 95% CI 1.82 to 4.52), protection against bronchial challenge (OR 1.81, 95% CI 1.32 to 2.49), and reduced need for medications (OR 2.00, 95% CI 1.46 to 2.72). CONCLUSION: The findings of this meta-analysis support the conclusion that SIT is effective in a population of patients with allergen-triggered asthma.

[Diversity of antigenic fractions of allergenic extracts and importance of the Western blot technique]. / Diversité des fractions antigéniques des extraits allergéniques et intérêt de la technique du Western blot.

The Phast-system groups together the techniques of electrophoresis and transfer. When applied to allergen extracts it allows identification of the allergenic protein fractions and shows their reactivity against sera from allergic patients. The Phast-system is indicated for the choice of the appropriate allergen for specific immunotherapy. If it is not possible to do it systematically, it should be done whenever there is a check to specific immunotherapy.