Molecular diagnosis for allergen immunotherapy.

The extensive use of allergen molecules in birth cohort studies revealed that atopic sensitization is a sequential IgE response to distinct non-cross-reacting molecules from the same allergenic source (ie, molecular spreading), starting with an initiator molecule. This phenomenon reaches different degrees of progression (monomolecular, oligomolecular, and polymolecular) according to the individual atopic propensity and allergen exposure, thus producing an extreme heterogeneity of IgE sensitization profiles in patient populations. In patients with allergic rhinitis, the broader the IgE molecular sensitization profile, the greater is the risk of asthma and other allergic comorbidities, such as oral allergy syndrome. Hence it has been proposed to anticipate immunologic intervention at disease onset (early allergen immunotherapy) or even earlier during the preclinical sensitization stage (allergen immunoprophylaxis). Diagnostic algorithms based on singleplex or multiplex molecular IgE tests allow the discrimination of genuine from cross-reacting sensitization and the selection of the right extracts for allergen immunotherapy composition. Patients with extreme molecular poly-sensitization and greater risk of asthma or other IgE-mediated comorbidities, can be easily identified by means of allergen microarray or macroarray procedures and might benefit from anti-IgE treatment. IgE molecular tests have opened the era of precision allergology, and their routine use should aim at cost-effectiveness, according to the principles of the Choosing Wisely initiative.

Application of immuno-PCR assay for the detection of serum IgE specific to Bermuda allergen.

In vivo and in vitro tests are the two major ways of identifying the triggering allergens in sensitized individuals with allergic symptoms. Both methods are equally significant in terms of sensitivity and specificity. However, in certain circumstances, in vitro methods are highly preferred because they circumvent the use of sensitizing drugs in patients. In current study, we described a highly sensitive immuno-PCR (iPCR) assay for serum IgE specific to Bermuda allergens. Using oligonucleotide-labelled antibody, we used iPCR for the sensitive detection of serum IgE. The nucleotide sequence was amplified using conventional PCR and the bands were visualized on 2.5% agarose gel. Results demonstrated a 100-fold enhancement in sensitivity of iPCR over commercially available enzyme-linked immunosorbent assay (ELISA) kit. Our iPCR method was highly sensitive for Bermuda-specific serum IgE and could be beneficial in allergy clinics.