Mesenteric lymph node transcriptome profiles in BALB/c mice sensitized to three common food allergens

<p>Abstract</p> <p>Background</p> <p>Food allergy is a serious health concern among infants and young children. Although immunological mechanism of food allergy is well documented, the molecular mechanism(s) involved in food allergen sensitization have not been well characterized. Therefore, the present study analyzed the mesenteric lymph node (MLN) transcriptome profiles of BALB/c mice in response to three common food allergens.</p> <p>Results</p> <p>Microarray analysis identified a total of 1361, 533 and 488 differentially expressed genes in response to β-lactoglobulin (BLG) from cow's milk, ovalbumin (OVA) from hen's egg white and peanut agglutinin (PNA) sensitizations, respectively (p < 0.05). A total of 150 genes were commonly expressed in all antigen sensitized groups. The expression of seven representative genes from microarray experiment was validated by real-time RT-PCR. All allergens induced significant ear swelling and serum IgG1 concentrations, whereas IgE concentrations were increased in BLG- and PNA-treated mice (p < 0.05). Treatment with OVA and PNA significantly induced plasma histamine concentrations (p < 0.05). The PCA demonstrated the presence of allergen-specific IgE in the serum of previously sensitized and challenged mice.</p> <p>Conclusions</p> <p>Immunological profiles indicate that the allergen dosages used are sufficient to sensitize the BALB/c mice and to conduct transcriptome profiling. Microarray studies identified several differentially expressed genes in the sensitization phase of the food allergy. These findings will help to better understand the underlying molecular mechanism(s) of food allergen sensitizations and may be useful in identifying the potential biomarkers of food allergy.</p

Evaluation of the Allergenicity Potential of TcPR-10 Protein from Theobroma cacao

Background: The pathogenesis related protein PR10 (TcPR-10), obtained from the Theobroma cacao-Moniliophthora perniciosa interaction library, presents antifungal activity against M. perniciosa and acts in vitro as a ribonuclease. However, despite its biotechnological potential, the TcPR-10 has the P-loop motif similar to those of some allergenic proteins such as Bet v 1 (Betula verrucosa) and Pru av 1 (Prunus avium). The insertion of mutations in this motif can produce proteins with reduced allergenic power. The objective of the present work was to evaluate the allergenic potential of the wild type and mutant recombinant TcPR-10 using bioinformatics tools and immunological assays. Methodology/Principal Findings: Mutant substitutions (T10P, I30V, H45S) were inserted in the TcPR-10 gene by sitedirected mutagenesis, cloned into pET28a and expressed in Escherichia coli BL21(DE3) cells. Changes in molecular surface caused by the mutant substitutions was evaluated by comparative protein modeling using the three-dimensional structure of the major cherry allergen, Pru av 1 as a template. The immunological assays were carried out in 8-12 week old female BALB/c mice. The mice were sensitized with the proteins (wild type and mutants) via subcutaneous and challenged intranasal for induction of allergic airway inflammation. Conclusions/Significance: We showed that the wild TcPR-10 protein has allergenic potential, whereas the insertion of mutations produced proteins with reduced capacity of IgE production and cellular infiltration in the lungs. On the other hand, in vitro assays show that the TcPR-10 mutants still present antifungal and ribonuclease activity against M. perniciosa RNA. In conclusion, the mutant proteins present less allergenic potential than the wild TcPR-10, without the loss of interesting biotechnological properties. (Résumé d'auteur

Variability in childhood allergy and asthma across ethnicity, language, and residency duration in El Paso, Texas: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>We evaluated the impact of migration to the USA-Mexico border city of El Paso, Texas (USA), parental language preference, and Hispanic ethnicity on childhood asthma to differentiate between its social and environmental determinants.</p> <p>Methods</p> <p>Allergy and asthma prevalence was surveyed among 9797 fourth and fifth grade children enrolled in the El Paso Independent School District. Parents completed a respiratory health questionnaire, in either English or Spanish, and a sub-sample of children received spirometry testing at their school. Here we report asthma and allergy outcomes across ethnicity and El Paso residency duration.</p> <p>Results</p> <p>Asthma and allergy prevalence increased with longer duration of El Paso residency independent of ethnicity and preferred language. Compared with immigrants who arrived in El Paso after entering first grade (18%), lifelong El Paso residents (68%) had more prevalent allergy (OR, 1.72; 95% CI, 1.32 - 2.24), prevalent asthma (OR, 1.75; 95% CI, 1.24 - 2.46), and current asthma (OR, 2.01; 95% CI, 1.37 - 2.95). Spirometric measurements (FEV₁/FVC and FEF_25-75) also declined with increasing duration of El Paso residency (0.16% and 0.35% annual reduction, respectively).</p> <p>Conclusion</p> <p>These findings suggest that a community-wide environmental exposure in El Paso, delayed pulmonary development, or increased health of immigrants may be associated with allergy and asthma development in children raised there.</p