Systemic and specific treatment for a global disease: allergen immunotherapy revisited

Sublingual immunotherapy in preschool children: an update

Allergen immunotherapy is a subject widely debated by allergists. Currently, there are controversial discussions focused on the sublingual route. Sublingual immunotherapy (SLIT) has so far been used in Europe, Asia and Australia for the treatment of allergic respiratory diseases. The minimum age to start specific immunotherapy with inhalant allergens in children has not been clearly established, and position papers discourage its use in children younger than 5 years of age. Nevertheless, it is known that SLIT efficacy is higher when SLIT is started at an earlier age. The aim of this review is to focus on studies in preschool children evaluating SLIT safety and efficacy, in order to improve this practice at an earlier age in childhood.

Profiling recombinant major birch pollen allergen Bet v 1a and carbamylated variants with CZE and CIEF

A preparation of recombinant birch pollen allergen of Betula verrucosa isoform 1a (Bet v 1a) containing chemically modified (carbamylated) variants has been analyzed by CZE and CIEF. In CZE, employing a 100 mmol/L MES buffer at pH 6.50, with 0.4 mmol/L tetraethylenepentamine (TEPA) added, allowed for the resolution of 17 protein fractions. The CIEF profiling of the allergen preparation required a combination of a wide-pH-range carrier ampholyte (CA) of pH 3-10 with two narrow-range CAs of pH 5-6 and 5-7. For CIEF, 91 mmol/L of glycine at pH 2.12 and 20 mmol/L of CHES at pH 10.00 were applied as anolyte and catholyte, respectively. The generated pH gradient was nonlinear with a flat slope for pH 4-6, thus providing an improved resolution. In CIEF, up to 18 protein fractions were distinguished as well. The pI of the target allergen Bet v 1a was 4.9 as determined by means of two pI marker compounds flanking the allergen. Relative purity of the target allergen within the preparation containing carbamylated variants was in accordance for both separation systems and varied between 40.7 and 42.8%.

Sublingual immunotherapy: the optimism and the issues

The acceptability of sublingual immunotherapy (SLIT) in guidelines or statements has recently increased. SLIT is currently used in Europe, Asia, and Australia for the treatment of allergic respiratory diseases. Four meta-analyses have shown that SLIT is an effective tool for the treatment of patients with asthma and/or rhinitis, and only conflicting results were reported for children with allergic rhinitis. Moreover, it offers logistic advantages and is safe. However, some unmet needs are to be faced, such as the difficulty of manufacturers to achieve the homogeneity of standardized vaccines, the magnitude of their clinical efficacy, and the pivotal question of an early intervention with SLIT in young children with IgE-mediated disorders. Altogether, SLIT has already given convincing results in respiratory diseases both in adults and children. In the future, this route of administration of allergic vaccines may improve even the treatment of patients with IgE-mediated food allergy. These patients indeed deserve better than allergen avoidance. The immunomodulatory treatment of allergic diseases probably has found a new tool; however, a more balanced understanding of this form of allergen immunotherapy is needed. This aim could be achieved through: (1) the improvement of products standardization quality; (2) an attempt to modify in children the natural course of allergic diseases; and (3) new research on mechanisms of action.