April 28, 2013

AllerTOP - a server for in silico prediction of allergens


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BMC Bioinformatics. 2013; 14(Suppl 6): S4.
Published online 2013 April 17. doi:  10.1186/1471-2105-14-S6-S4
PMCID: PMC3633022

AllerTOP - a server for in silico prediction of allergens

Abstract

Background

Allergy is a form of hypersensitivity to normally innocuous substances, such as dust, pollen, foods or drugs. Allergens are small antigens that commonly provoke an IgE antibody response. There are two types of bioinformatics-based allergen prediction. The first approach follows FAO/WHO Codex alimentarius guidelines and searches for sequence similarity. The second approach is based on identifying conserved allergenicity-related linear motifs. Both approaches assume that allergenicity is a linearly coded property. In the present study, we applied ACC pre-processing to sets of known allergens, developing alignment-independent models for allergen recognition based on the main chemical properties of amino acid sequences.

Results

A set of 684 food, 1,156 inhalant and 555 toxin allergens was collected from several databases. A set of non-allergens from the same species were selected to mirror the allergen set. The amino acids in the protein sequences were described by three z-descriptors (z1zand z3) and by auto- and cross-covariance (ACC) transformation were converted into uniform vectors. Each protein was presented as a vector of 45 variables. Five machine learning methods for classification were applied in the study to derive models for allergen prediction. The methods were: discriminant analysis by partial least squares (DA-PLS), logistic regression (LR), decision tree (DT), naïve Bayes (NB) and nearest neighbours (kNN). The best performing model was derived by kNN at = 3. It was optimized, cross-validated and implemented in a server named AllerTOP, freely accessible at http://www.pharmfac.net/allertop. AllerTOP also predicts the most probable route of exposure. In comparison to other servers for allergen prediction, AllerTOP outperforms them with 94% sensitivity.

Conclusions

AllerTOP is the first alignment-free server for in silico prediction of allergens based on the main physicochemical properties of proteins. Significantly, as well allergenicity AllerTOP is able to predict the route of allergen exposure: food, inhalant or toxin.

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Articles from BMC Bioinformatics are provided here courtesy of BioMed Central

Eosinophilic Inflammation in Allergic Asthma


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Front Pharmacol. 2013; 4: 46.
Published online 2013 April 17. doi:  10.3389/fphar.2013.00046
PMCID: PMC3627984

Eosinophilic Inflammation in Allergic Asthma

Abstract

Eosinophils are circulating granulocytes involved in pathogenesis of asthma. A cascade of processes directed by Th2 cytokine producing T-cells influence the recruitment of eosinophils into the lungs. Furthermore, multiple elements including interleukin (IL)-5, IL-13, chemoattractants such as eotaxin, Clara cells, and CC chemokine receptor (CCR)3 are already directly involved in recruiting eosinophils to the lung during allergic inflammation. Once recruited, eosinophils participate in the modulation of immune response, induction of airway hyperresponsiveness and remodeling, characteristic features of asthma. Various types of promising treatments for reducing asthmatic response are related to reduction in eosinophil counts both in human and experimental models of pulmonary allergic inflammation, showing that the recruitment of these cells really plays an important role in the pathophysiology of allergic diseases such asthma.
Keywords: airway remodeling, asthma, eosinophils, experimental models of asthma, inflammation, respiratory hypersensitivity

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Articles from Frontiers in Pharmacology are provided here courtesy of Frontiers Media SA

Determinants of Food Allergy


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Immunol Allergy Clin North Am. Author manuscript; available in PMC 2013 February 1.
Published in final edited form as:
PMCID: PMC3312744
NIHMSID: NIHMS363930

Determinants of Food Allergy

Madhan Masilamani, PhD,a,b Scott Commins, MD, PhD,c and Wayne Shreffler, MD, PhDd,*

SUMMARY

Much has been learned by identifying the molecules that can be recognized by IgE from patients with allergies. Increasingly, by correlating patterns of sensitization with clinical features, it has become possible to distinguish molecules responsible for primary sensitization (complete allergens) from those that are more likely cross-reactive targets. In the case of animal allergens, evolutionary distance seems to be an important factor in determining allergenicity. However, until more is understood regarding the mechanistic details of primary sensitization, including the participation of molecules that stimulate innate immune responses and the repertoire of T-cell antigens, molecules that may or may not themselves be important B-cell antigens, we will not be able to explain fundamental questions, such as why peanut allergy is more severe than soy allergy or why tick exposure is associated with clinically relevant sensitization to a carbohydrate epitope.
Keywords: Food allergy, Allergen, Plant food allergens, Animal food allergens, Peanut, Soy, Cross-reactive carbohydrate determinants, Alpha-gal

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Lactobacillus rhamnosus GG Supplementation for Preventing Respiratory Infections in Children

April 2013; Volume 50: Number 4


Lactobacillus rhamnosus GG Supplementation for Preventing Respiratory Infections in Children: A Meta-analysis of Randomized, Placebo-controlled Trials – Shan Liu, PengWei Hu, Xiaoxin Du, Tao Zhou and Xiaofang Pei377[PDF Format] [Web Table I] [Web Table II]


Clinical manifestations in the oral cavity in patients with hyper-IgE syndrome


Clinical manifestations in the oral cavity in patients with hyper-IgE syndrome.

Dorota Olczak-Kowalczyk, Anna Matosek, Edyta Heropolitańska-Pliszka, Ewa Bernatowska

(Centr Eur J Immunol 2013; 38 (1): 92-99)
DOI (digital object identifier): 10.5114/ceji.2013.34363
Introduction: Hyper-IgE syndrome is a rare an autosomal recessive or dominant manner due to gene mutations. This syndrome, from mutations in the STAT3 gene, is characterized by elevated levels of IgE > 2000 IU/ml, eczema, skin abscesses, recurrent respiratory infections, skeletal abnormalities, oral mucosal lesions, impaired eruption of permanent teeth and root resorption of deciduous teeth.

Aim of the study: Determine phenotypic characteristics of hyper-IgE syndrome in the oral cavity with regard to a modifying impact of environmental factors.

Results: Examination of the oral mucosa revealed white lichenoid lesions, atrophy of the lingual papillae, median schistoglossia, palatine fibrosis, erosions, ulceration and scarring, angular cheilitis. Candida albicans was identified, despite antimycotic treatment. Dental examination revealed caries, unerupted teeth, persistent deciduous teeth, and tooth wear. The phenotypic variability in the oral cavity might have been due to environmental factors.

Conclusions: Although the genetic causes of hyper-IgE have been identified, the pathogenesis of oral lesions in those patients remains to be clarified. The current knowledge allows associating the oral mucosal lesions, i.e., fungus infections, hyperkeratosis and fibrosis, with the STAT3 gene mutation.

It also helps to consider its role in odontogenic disorders, particularly in inhibiting eruption of permanent teeth and root resorption in deciduous dentition.

April 27, 2013

How molds can effect the immune system


Dr. Charles Barnes describes how molds can effect the immune system. Held on Feb 11, 2013.


About Conferences On-Line Allergy

The use of antiIgE for treating allergic disorders.



Dr. Tara Federly discusses the use of antiIgE for treating allergic disorders. Held on Feb 8, 2013.


About Conferences On-Line Allergy

Latest information on mast cells and mastocytosis.



Cem Akin, MD, PhD reviews the latest information on mast cells and mastocytosis. Held on Feb 11, 2013.


About Conferences On-Line Allergy