In conclusion, we demonstrated that plasma FBLN5, a component of elastic fibers, is a novel marker of liver fibrosis in patients with chronic hepatitis C. Liver FBLN5 colocalized with αSMA-positive HSCs, and in vitro experimentation confirmed that FBLN5 was upregulated in activated HSCs and secreted into cultured medium. Here, ACTA1 is linked to chronic hepatitis C virus infection.