Systemic sclerosis is a rare autoimmune rheumatic disease (incidence 7-33 per 100,000 individuals) that causes connective tissue sclerosis, vascular abnormalities, and atrophy of the skin and various internal organs. The condition is rare and invalidating and despite some patients have a “milder form” with solely involvement of skin and gastroenteric organs, others develop lung fibrosis, which is associated with high mortality. The treatment options are limited and there is no clear way to determine which patient will develop lung fibrosis. The only practice implemented into the clinics is measurements of specific autoantibodies, which are associated with an increased risk of developing lung fibrosis, although with low specificity. Hence, there is a great clinical need for easy-to-measure biomarkers to identify patients with high risk of developing lung fibrosis. The objective of this project is to run a pilot study to identify circulating biomarkers to predict the risk of developing lung fibrosis in patients with systemic sclerosis. To identify underlying biological pathways of severe disease progression that could help find drug targets and develop new therapies.