HLA-B27 alters BMP/TGFβ signalling in Drosophila, revealing putative pathogenic mechanism for spondyloarthritis - Archive ouverte HAL Access content directly
Journal Articles Annals of the Rheumatic Diseases Year : 2019

HLA-B27 alters BMP/TGFβ signalling in Drosophila, revealing putative pathogenic mechanism for spondyloarthritis

(1, 2) , (2) , (1) , (2) , (1) , (1) , (1, 2) , (2) , (1) , (2) , (2) , (1)
1
2

Abstract

Objectives: The human leucocyte antigen (HLA)-B27 confers an increased risk of spondyloarthritis (SpA) by unknown mechanism. The objective of this work was to uncover HLA-B27 non-canonical properties that could explain its pathogenicity, using a new Drosophila model. Methods: We produced transgenic Drosophila expressing the SpA-associated HLA-B*27:04 or HLA-B*27:05 subtypes, or the non-associated HLA-B*07:02 allele, alone or in combination with human β2-microglobulin (hβ2m), under tissue-specific drivers. Consequences of transgenes expression in Drosophila were examined and affected pathways were investigated by the genetic interaction experiments. Predictions of the model were further tested in immune cells from patients with SpA. Results: Loss of crossveins in the wings and a reduced eye phenotype were observed after expression of HLA-B*27:04 or HLA-B*27:05 in Drosophila but not in fruit flies expressing the non-associated HLA-B*07:02 allele. These HLA-B27-induced phenotypes required the presence of hβ2m that allowed expression of well-folded HLA-B conformers at the cell surface. Loss of crossveins resulted from a dominant negative effect of HLA-B27 on the type I bone morphogenetic protein (BMP) receptor saxophone (Sax) with which it interacted, resulting in elevated mothers against decapentaplegic (Mad, a Drosophila receptor-mediated Smad) phosphorylation. Likewise, in immune cells from patients with SpA, HLA-B27 specifically interacted with activin receptor-like kinase-2 (ALK2), the mammalian Sax ortholog, at the cell surface and elevated Smad phosphorylation was observed in response to activin A and transforming growth factor β (TGFβ). Conclusions: Antagonistic interaction of HLA-B27 with ALK2, which exerts inhibitory functions on the TGFβ/BMP signalling pathway at the cross-road between inflammation and ossification, could adequately explain SpA development.
Fichier principal
Vignette du fichier
Ann Rheum Dis 2019_BGrandon_V acceptee.pdf (5.53 Mo) Télécharger le fichier
Origin : Files produced by the author(s)

Dates and versions

hal-02975533 , version 1 (11-12-2020)

Identifiers

Cite

Benjamin Grandon, Aurore Rincheval-Arnold, Nadège Jah, Jean-Marc Corsi, M Araujo, et al.. HLA-B27 alters BMP/TGFβ signalling in Drosophila, revealing putative pathogenic mechanism for spondyloarthritis. Annals of the Rheumatic Diseases, 2019, 78 (12), pp.1653. ⟨10.1136/annrheumdis-2019-215832⟩. ⟨hal-02975533⟩
73 View
259 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More