华亿体育（中国）游戏平台

Release date：2019-06-26

JACI

[IF:13.1]

Dissection of the IgE and T-cell recognition of the major group 5 grass pollen allergen Phl p 5
DOI: https://doi.org/10.1016/j.jaci.2013.08.038
Background
The major timothy grass pollen allergen Phl p 5 belongs to the most potent allergens involved in hay fever and asthma.
Objective
This study characterized immune-dominant IgE- and T-cell–recognition sites of Phl p 5.
Methods
Seven peptides, P1 to P7 with a length of 31 to 38 amino acids that spanned the Phl p 5 sequence, were synthesized, characterized by circular dichroism spectroscopy, and tested for IgE reactivity, basophil activation, and T-cell reactivity. Carrier-bound peptides were studied for their ability to induce IgG antibodies in rabbits which recognize Phl p 5 or cross-reactive allergens from different grass species. Peptide-specific antibodies were tested for the capability to inhibit IgE reactivity to Phl p 5 and allergen-induced basophil activation of patients with allergy.
Results
The peptides exhibited no secondary structure and showed no IgE reactivity or relevant allergenic activity, indicating that Phl p 5 IgE epitopes are conformational. Except for P3, peptide-specific IgG antibodies blocked IgE binding to Phl p 5 of patients with allergy and cross-reacted with temperate grasses. IgE inhibition experiments and molecular modeling identified several clustered conformational IgE epitopes on the N- as well as C-terminal domain of Phl p 5. P4, which stimulated the strongest T-cell and cytokine responses in patients, was not part of the major IgE-reactive regions.
Conclusion
Our study shows an interesting dissociation of the major IgE- and T-cell–reactive domains in Phl p 5 which provides a basis for the development of novel forms of immunotherapy that selectively target IgE or T-cell responses.
All Authors:
Margarete Focke-Tejkl Raffaela Campana Renate Reininger Christian Lupinek Katharina Blatt Peter Valent Tea Pavkov-Keller Walter KellerWalter KellerRudolf Valenta

2019-5-17 Article