Abstract
Anti-endothelial cell antibodies (AECAs) have been identified in patients with systemic sclerosis (SSc) with and without pulmonary arterial hypertension (PAH) and in patients with idiopathic pulmonary arterial hypertension (iPAH). However, their target antigens remain poorly identified.
Sera from 24 patients with SSc without PAH, 20 patients with SSc with PAH, 30 with iPAH and 12 healthy controls were collected. Target antigens were identified by two-dimensional electrophoresis and immunoblotting in protein extracts of human umbilical vein endothelial cells. Targeted antigens were identified by mass spectrometry.
Serum immunoglobulin G from patients with SSc with or without PAH and patients with iPAH specifically recognised 110, 82 and 37 protein spots, respectively. Among others, target antigens of AECAs included lamin A/C, tubulin β-chain and vinculin. One-dimension immunoblotting experiments confirmed the identification of lamin A/C and tubulin β-chain.
In conclusion, our results confirm the presence of AECA in patients with systemic sclerosis with and without pulmonary arterial hypertension and in those with idiopathic pulmonary arterial hypertension, and provide evidence for the identification of target antigens of these autoantibodies including lamin A/C and tubulin β-chain.
Footnotes
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Support Statement
H. Dib received financial support from AMPLI and ARMIIC (Association pour la Recherche en Médecine Interne et en Immunologie Clinique). M.C. Tamby received a grant from Pfizer and a Contrat d'Investigation et de Recherche Clinique (PHRC National Auto-HTAP). We thank Pfizer and the Direction de la Recherche Clinique of the Assistance Publique-Hôpitaux de Paris for supporting the project CIRC 05066, HTAP-Ig. G. Bussone received a financial support from AMPLI (Avenir Mutualiste des Professions Libérales et Indépendantes), the Société Nationale Française de Médecine Interne (SNFMI), the Fonds d'Etudes et de Recherche du Corps Médical des Hôpitaux de Paris and the Direction Régionale des Affaires Sanitaires et Sociales d'Ile-de-France. A. Regent received financial support from the Direction Régionale et Départementale des Affaires Sabitaires et Sociales de Champagne-Ardennes et de la Marne and the SNFMI. We also thank the Association des Sclérodermiques de France, the Groupe Français de Recherche sur la Sclérodermie and the Unité de Recherche Clinique Paris Centre.
Statement of Interest
Statements of interest for M.C. Tamby, A. Berezné, L. Guillevin, G. Simonneau, M. Humbert and L. Mouthon, and for the study itself can be found at www.erj.ersjournals.com/site/misc/statements.xhtml
- Received November 25, 2010.
- Accepted September 22, 2011.
- ©ERS 2012