The minor house dust mite allergen Der p 13 is a fatty acid‐binding protein and an activator of a TLR2‐mediated innate immune response. Issue 10 (29th April 2016)

• Record Type: Journal Article
• Authors: Satitsuksanoa, P.; Kennedy, M.; Gilis, D.; Le Mignon, M.; Suratannon, N.; Soh, W. T.; Wongpiyabovorn, J.; Chatchatee, P.; Vangveravong, M.; Rerkpattanapipat, T.; Sangasapaviliya, A.; Piboonpocanun, S.; Nony, E.; Ruxrungtham, K.; Jacquet, A.
• Other Names: Thantiworasit Pattarawat investigator.; Pulsawat Pinya investigator.; Daengsuwan Tassalalpa investigator.; Laisuan Wannada investigator.; Tongdee Malinee investigator.; Dchapaphapeaktak Nizchapha investigator.; Boonpiyathad Tadech investigator.
• Is Part Of: Allergy. Volume 71:Issue 10(2016:Oct.)
• Page Start: 1425
• Page End: 1434
• Publication Date: 2016-04-29
• Subjects: allergen -- Der p 13 -- house dust mite -- IgE reactivity -- innate immunity -- lipid‐binding protein -- TLR2; Allergy -- Periodicals; 616.97
• DOI: 10.1111/all.12899
• Languages: English
• ISSNs: 0105-4538

Abstract

Abstract: Background: The house dust mite (HDM ) allergen Der p 13 could be a lipid‐binding protein able to activate key innate signaling pathways in the initiation of the allergic response. We investigated the IgE reactivity of recombinant Der p 13 (rDer p 13), its lipid‐binding activities, and its capacity to stimulate airway epithelium cells. Methods: Purified rDer p 13 was characterized by mass spectrometry, circular dichroism, fluorescence‐based lipid‐binding assays, and in silico structural prediction. IgE‐binding activity and allergenic potential of Der p 13 were examined by ELISA, basophil degranulation assays, and in vitro airway epithelial cell activation assays. Results: Protein modeling and biophysical analysis indicated that Der p 13 adopts a β‐barrel structure with a predominately apolar pocket representing a potential binding site for hydrophobic ligands. Fluorescent lipid‐binding assays confirmed that the protein is highly selective for ligands and that it binds a fatty acid with a dissociation constant typical of lipid transporter proteins. The low IgE‐binding frequency (7%, n = 224) in Thai HDM‐allergic patients as well as the limited propensity to activate basophil degranulation classifies Der p 13 as a minor HDM allergen. Nevertheless, the protein with its presumptively associated lipid(s) triggered the production of IL‐8 and GM‐CSF in respiratory epithelial cells through a TLR2‐, MyD88‐, NF‐kB‐, and MAPK‐dependent signaling pathway. Conclusions: Although a minor allergen, Der p 13 may, through its lipid‐binding capacity, play a role in the initiation of the HDM‐allergic response through TLR2 activation.