Peptide Allergen Immunotherapy: A New Perspective in Olive-Pollen Allergy

Abstract

Allergic diseases are highly prevalent disorders, mainly in industrialized countries where they constitute a high global health problem. Allergy is defined as an immune response “shifted toward a type 2 inflammation” induced by the interaction between the antigen (allergen) and IgE antibodies bound to mast cells and basophils that induce the release of inflammatory mediators that cause the clinical symptoms. Currently, allergen-specific immunotherapy (AIT) is the only treatment able to change the course of these diseases, modifying the type 2 inflammatory response by an allergenic tolerance, where the implication of T regulatory (Treg) cells is considered essential. The pollen of the olive tree is one of the most prevalent causes of respiratory allergic diseases in Mediterranean countries, inducing mainly nasal and conjunctival symptoms, although, in areas with a high antigenic load, olive-tree pollen may cause asthma exacerbation. Classically, olive-pollen allergy treatment has been based on specific immunotherapy using whole-olive pollen extracts. Despite extracts standardization, the effectiveness of this strategy varies widely, therefore there is a need for more effective AIT approaches. One of the most attractive is the use of synthetic peptides representing the B- or T-cell epitopes of the main allergens. This review summarizes experimental evidence of several T-cell epitopes derived from the Ole e 1 sequence to modulate the response to olive pollen in vitro, associated with several possible mechanisms that these peptides could be inducing, showing their usefulness as a safe preventive tool for these complex diseases.

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

“…Regions that exclusively elicited IgG4 during treatment showed epitopes from 12 up to 33 residues. That length is in the middle of existing data for peptide vaccines, where IgE-mediated peptides are longer, being 20–40 amino acids and typically dependent on a folded tertiary structure [ 49 , 50 ]. Shorter peptides, 10–17 aa, are mainly T-cell epitopes which are designed to be recognized by MHC-class II molecules.…”

“…Shorter peptides, 10–17 aa, are mainly T-cell epitopes which are designed to be recognized by MHC-class II molecules. Furthermore, those shorter peptides should be unable to bind IgE-FcεRI on effector cells due to their small size [ 50 ].…”

Pre-pubertal sublingual immunotherapy is more effective than immunotherapy during puberty in allergic rhinitis and asthma

“…This therapy can alleviate respiratory symptoms, reduce the use of symptomatic medications, and improve patients' quality of life [19]. Immunotherapy is a diseasemodifying treatment modality that prevents the emergence of new allergies and modi es the course of respiratory allergic diseases [20]. Allergen-speci c immunotherapy has developed several routes of administration, of which subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) are the two most common modes of administration [21].…”

Capítulo 3. Alergia respiratoria

“…En modelos experimentales se ha demostrado la eficacia de la ITA basada en el alergeno Ole e 1. 50 Para Bet v 1 se llevaron a cabo estudios clínicos fase II y III.…”