The ImmunoCAP ISAC molecular allergology approach in adult multi-sensitized Italian patients with respiratory symptoms

Clin Biochem. 2011 Aug;44(12):1005-11 Giovanni Melioli a,*, Floriano Bonifazi b, Sergio Bonini c, Enrico Maggi d, Michele Mussap e, Gianni Passalacqua f, Enzo Renato Rossi g, Angelo Vacca h, Giorgio Walter Canonica f, and on behalf of the Italian Board for ISAC (IBI) 1


a Dipartimento di Medicina Sperimentale, U.O. Laboratorio di Analisi, Istituto Giannina Gaslini, Genoa, Italy, b Dipartimento di Malattie Respiratorie ed Allergiche, U.O. Allergologia, Azienda Ospedaliera Umberto I, Torrette, Ancona, Italy, c Istituto di Neurologia e Medicina Molecolare, CNR, Rome and II Università di Napoli, Naples, Italy, d U.O. Immunoallergologia, Università degli Studi di Firenze, Policlinico Careggi, Florence, Italy, e U.O. Laboratorio di Analisi, Ospedale San Martino, Genoa, Italy, f U.O. Pneumologia e Malattie Allergiche, Università di Genova, Genoa, Italy, g Rete di Allergologia Regione Piemonte, Cuneo, Italy, h U.O. Allergologia e Immunologia Clinica, Università di Bari, Bari, Italy







Objectives: To evaluate the performances of an allergen microarray in multi-sensitized allergic patients with respiratory symptoms.


Design and methods: 321 patients and 92 controls were included in this study. Specific serum IgE were assayed using ImmunoCAP ISAC, a microarray containing 103 components derived from 47 allergens and results were compared with extract-based ImmunoCAP Allergens sIgE to 15 common airborne allergens.


Results: The reproducibility of ISAC was good. The Positive Percent Agreement (PPA) varied between 75% and 100% for sIgE levels above 1 kUA/l. For samples with sIgE levels below 0.1 kUA/l, the Negative Percent Agreement (NPA) ranged between 90% and 100%. Notably, 58% of respiratory allergy patients had IgE to foodspecific proteins and 52% resulted sensitized to cross-reactive pan-allergens.


Conclusion: ImmunoCAP ISAC detects allergen sensitization at component level and adds important information by defining both cross and co-sensitization to a large variety of allergen molecules.