The blood collection and measurement of sOX40L, as well as other serum factors were conducted as reported previously.[15] Briefly, peripheral blood samples (5 mL) were collected in tubes containing ethylenediaminetetraacetic acid (EDTA) to obtain monocytes or did not contain EDTA to obtain serum within 24 h of admission. Isopaque-Ficoll gradient centrifugation was conducted to obtain the peripheral venous blood mononuclear cells and monocytes were harvested and collected in RPMI1640 medium. Non-EDTA blood was immersed in ice and the supernatant was obtained after centrifugation with 1500 × g for 10 min at 4°C and then the supernatants were harvested and stored at −70°C. Enzyme-linked immunosorbent assay (ELISA) was subsequently performed using commercial ELISA kits (BD Biosciences, San Diego, CA) to determine the soluble serum levels of PGRN, sOX40L, IL-4, IL-6, and IL-10 following the manufacturer's protocols.