2.2.1. S100A6 Assay

Serum S100A6 levels were determined using commercial sandwich ELISA kit (ELH-S-100A6-1 Raybiotech, Peachtree Corners, GA, USA) according to the manufacturer's instructions. The intra-assay and inter-assay coefficient of variation were 10% and 12%. The minimum detectable concentration of S100A6 was 0.06 ng/mL.
