Setae from the pine processionary moth (Thaumetopoea pityocampa) contain several relevant allergens

BACKGROUND: Pine processionary larvae produce urticating hairs (setae) that serve for protection against predators. Setae induce cutaneous reactions in animals and humans. The presence of toxic or allergic mechanisms is a matter of debate. OBJECTIVES: To detect the presence of allergens in setae and to characterize them. MATERIALS AND METHODS: Setae extracts were characterized by gel staining and immunoblot, with sera from patients with immediate reactions and positive prick test reactions, as well as a rabbit antiserum raised against setae. Setae proteins were fractionated by high-performance liquid chromatography. The most relevant allergen was analysed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS), and its sequence was deduced from an expressed sequence tag bank. Results. Setae contained at least seven different allergens. The most intense detection corresponded to a protein of MW ~ 14,000 that was similar to thaumetopoein, a previously described protein with mast cell-degranulating properties. MALDI-MS-based de novo sequencing provided a partial amino acid sequence different from that of the previously described allergen Tha p 1, and it was named Tha p 2. This allergen was detected in 61% of patients, and it is therefore a new major caterpillar allergen. CONCLUSIONS: Penetration of the setae from the pine processionary caterpillar delivers their allergenic content in addition to causing mechanical or toxic injury.This work was supported by URTICLIM, a French project funded by the ‘Agence Nationale de la Recherche’ (ANR 07BDIV 013). Ana I. Rodriguez-Mahillo is a beneficiary of contract CA07/00046 from the Instituto de Salud Carlos III, Ministerio de Ciencia e Innovacion, Spain.S

Setae from the pine processionary moth (Thaumetopoea pityocampa) contain several relevant allergens

Background. Pine processionary larvae produce urticating hairs (setae) that serve for protection against predators. Setae induce cutaneous reactions in animals and humans. The presence of toxic or allergic mechanisms is a matter of debate. Objectives. To detect the presence of allergens in setae and to characterize them. Materials and methods. Setae extracts were characterized by gel staining and immunoblot, with sera from patients with immediate reactions and positive prick test reactions, as well as a rabbit antiserum raised against setae. Setae proteins were fractionated by high-performance liquid chromatography. The most relevant allergen was analysed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS), and its sequence was deduced from an expressed sequence tag bank. Results. Setae contained at least seven different allergens. The most intense detection corresponded to a protein of MW 3c 14 000 that was similar to thaumetopoein, a previously described protein with mast cell-degranulating properties. MALDI-MS-based de novo sequencing provided a partial amino acid sequence different from that of the previously described allergen Tha p 1, and it was named Tha p 2. This allergen was detected in 61% of patients, and it is therefore a new major caterpillar allergen. Conclusions. Penetration of the setae from the pine processionary caterpillar delivers their allergenic content in addition to causing mechanical or toxic injury. \ua9 2012 John Wiley & Sons A/S

<i>PRPH2</i>-Related Retinal Dystrophies: Mutational Spectrum in 103 Families from a Spanish Cohort

PRPH2, one of the most frequently inherited retinal dystrophy (IRD)-causing genes, implies a high phenotypic variability. This study aims to analyze the PRPH2 mutational spectrum in one of the largest cohorts worldwide, and to describe novel pathogenic variants and genotype–phenotype correlations. A study of 220 patients from 103 families recruited from a database of 5000 families. A molecular diagnosis was performed using classical molecular approaches and next-generation sequencing. Common haplotypes were ascertained by analyzing single-nucleotide polymorphisms. We identified 56 variants, including 11 novel variants. Most of them were missense variants (64%) and were located in the D2-loop protein domain (77%). The most frequently occurring variants were p.Gly167Ser, p.Gly208Asp and p.Pro221_Cys222del. Haplotype analysis revealed a shared region in families carrying p.Leu41Pro or p.Pro221_Cys222del. Patients with retinitis pigmentosa presented an earlier disease onset. We describe the largest cohort of IRD families associated with PRPH2 from a single center. Most variants were located in the D2-loop domain, highlighting its importance in interacting with other proteins. Our work suggests a likely founder effect for the variants p.Leu41Pro and p.Pro221_Cys222del in our Spanish cohort. Phenotypes with a primary rod alteration presented more severe affectation. Finally, the high phenotypic variability in PRPH2 hinders the possibility of drawing genotype–phenotype correlations