A novel allergen-adjuvant conjugate suitable for specific immunotherapy of respiratory allergy

作者：Fili Lucia; Vultaggio Alessandra; Cardilicchia Elisa; Manuelli Cinzia; Casini Andrea; Nencini Francesca; Maggi Laura; Pratesi Sara; Petroni Giulia; Boscaro Francesca; Guarna Antonio; Occhiato Ernesto G; Romagnani Sergio; Maggi Enrico; Parronchi Paola^*

来源：Journal of Allergy and Clinical Immunology, 2013, 132(1): 84-U168.

DOI：10.1016/j.jaci.2013.01.030

• Adjuvants
• immunotherapy
• allergy
• vaccines
• Toll-like receptors
• adenine derivatives
• T-H cells

Background: Several approaches to find a better adjuvant, focus immunomodulation, and reduce allergenicity are under investigation to improve the efficacy and safety of specific immunotherapy. %26lt;br%26gt;Objective: We performed an investigation of the in vitro and in vivo effects of a purified allergen chemically conjugated to a novel 8-OH modified adenine as an adjuvant. %26lt;br%26gt;Methods: Purified group 2 major allergen from house dust mite chemically conjugated to 4-(6-amino-9-benzyl-8-hydroxy-9H-purin-2-ylsulfanyl)-butyric acid succinimidyl ester was analyzed by using mass spectrometry. The adduct (nDer p 2-Conj) was assayed for Toll-like receptor activation on transfected HEK293 cells, stimulation of innate cells, and effects on the functional phenotype of specific T-cell lines and clones by means of flow cytometry, real-time PCR, and expression of T-H-related transcription factors. Lung cells and sera of nDer p 2-Conj-sensitized C57Bl/6 mice were studied by means of cytology, histology, real-time PCR, and ELISA. %26lt;br%26gt;Results: nDer p 2-Conj stimulated IL-12 and IFN-alpha production from monocytes and plasmacytoid dendritic cells, respectively, retaining the ability to trigger Toll-like receptor 7 exclusively, and expanded human allergen-specific lymphocytes with reduced ability to produce T(H)2-related cytokines and increased IFN-gamma levels, as based on GATA-3/T-bet expression. In vivo adduct-sensitized mice exhibited reduced eosinophil infiltration and IL-13 expression in the airways, IFN-gamma upregulation together with IgE downregulation, and an increase in allergen-specific IgG(2a) levels in sera. The conjugate exhibited reduced ability to activate human FceRI(+) cells without inducing T(H)17 cells or autoantibodies. %26lt;br%26gt;Conclusions: The codelivery of an allergen with a modified adenine as a conjugate inducing modulatory cytokines from innate cells redirects in vitro and in vivo pathogenic T(H)2 responses without eliciting harmful effects.

• 出版日期2013-7