IgE and IgG4 Epitopes of Dermatophagoides and Blomia Allergens before and after Sublingual Immunotherapy.

Sublingual immunotherapy (SLIT) is used worldwide to treat house dust mites (HDM) allergy. Epitope specific immunotherapy with peptide vaccines is used far less, but it is of great interest in the treatment of allergic reactions, as it precludes the drawbacks of allergen extracts. The ideal peptide candidates would bind to IgG, blocking IgE-binding. To better elucidate IgE and IgG4 epitope profiles during SLIT, sequences of main allergens, Der p 1, 2, 5, 7, 10, 23 and Blo t 5, 6, 12, 13, were included in a 15-mer peptide microarray and tested against pooled sera from 10 patients pre- and post-1-year SLIT. All allergens were recognized to some extent by at least one antibody isotype and peptide diversity was higher post-1-year SLIT for both antibodies. IgE recognition diversity varied among allergens and timepoints without a clear tendency. Der p 10, a minor allergen in temperate regions, was the molecule with more IgE-peptides and might be a major allergen in populations highly exposed to helminths and cockroaches, such as Brazil. SLIT-induced IgG4 epitopes were directed against several, but not all, IgE-binding regions. We selected a set of peptides that recognized only IgG4 or were able to induce increased ratios of IgG4:IgE after one year of treatment and might be potential targets for vaccines.

Immunophenotypical Characterization of a Brazilian POIS (Post-Orgasmic Illness Syndrome) Patient: Adding More Pieces to Puzzle.

Post-orgasmic illness syndrome (POIS) is a rare condition characterized by post-ejaculatory symptoms. Here is reported the first Brazilian POIS patient. Immunological investigation did not confirm the previous hypothesis of a hypersensitivity reaction. Cell immunophenotyping comparing healthy individuals produced evidence of abnormalities not associated to clinical manifestations. The patient was submitted to specific immunotherapy with transient clinical response and was referred to a psychologist but did not demonstrate clinical improvement of symptoms. Therefore, etiology of POIS remains unclear.