Angiogenic T Cells: potential biomarkers for the early diagnosis of interstitial lung disease in autoimmune diseases?

Background: We explored, for the first time, the contribution of angiogenic T cells (TAng) in interstitial lung disease associated to autoimmune disease (AD-ILD+) as potential biomarkers of the disease, evaluating their role in the underlying vasculopathy and lung fibrosis. Additionally, the relationship of TAng with clinical manifestations and cellular and molecular endothelial dysfunctionrelated biomarkers was assessed. (2) Methods: We included 57 AD-ILD+ patients (21 with rheumatoid arthritis (RA)-ILD+, 21 with systemic sclerosis (SSc)-ILD+ and 15 with other AD-ILD+) and three comparative groups: 45 AD-ILD-- patients (25 RA-ILD-- and 20 SSc-ILD--); 21 idiopathic pulmonary fibrosis (IPF) patients; 21 healthy controls (HC). TAng were considered as CD3+CD184+CD31+ by flow cytometry. (3) Results: A similar TAng frequency was found between AD-ILD+ and IPF, being in both cases lower than that observed in AD-ILD- and HC. A lower TAng frequency was associated with negative Scl-70 status and lower FEV1/FVC ratio in SSc-ILD+, as well as with men in RA-ILD+ and non-specific interstitial pneumonia radiological pattern in other AD-ILD+. No relationship between TAng and endothelial progenitor cells, endothelial cells and vascular endothelial growth factor gene expression and protein levels was disclosed. (4) Conclusions: Our findings suggest TAng as potential biomarkers for the early diagnosis of ILD in AD. ; Funding: V.P.-C. and S.R.-M. are supported by funds of RETICS Program [RD16/0012/0009, Instituto de Salud Carlos III (ISCIII), co-funded by European Regional Development Fund (ERDF); FG is supported by funds of the RICORS Program (RD21/0002/0025) from ISCIII, co-funded by the European Union; OG is staff personnel of Xunta de Galicia (Servizo Galego de Saude (SERGAS) through a research-staff stabilization contract (ISCIII/SERGAS) and his work is funded by ISCIII and ERDF [RD16/0012/0014 (RIER) and PI17/00409]. He is the beneficiary of project funds from the Research Executive Agency of the European Union in the ...