Promotion of cell aggregation, keratocan expression and inhibition of α-SMA in HCF are dose-dependent and not mediated by integrin β1 signaling or cell death. Passage 3 HCF were seeded on plastic with or without immobilized HC-HA/PTX3 or soluble HC-HA/PTX3 for 1 day at the concentration of 0, 5, 10, or 20 µg/mL (A, Bar = 100 µm). HCF seeded on immobilized HC-HA/PTX3 in DMEM+10% FBS were switched to DMEM+ITS for 24 hours before being added with 10 ng/mL TGFβ1 for 72 hours before immunostaining to α-SMA (A, nuclear staining by Hoechst 33342, Bar = 100 µm). Expression of keratocan was determined in HCF on immobilized HC-HA/PTX3 (20 µg/ml) at Day 2 (B) while that of integrin β1 (activated) and pFAK (Tyr-397) at 15 minutes (C) by Western blot using β-actin and total FAK as the loading controls. Trypan blue staining was performed on HCF after cultured on immobilized HC-HA/PTX3 for 7 days and counted as stained cells in total cells (%) (D, n = 3, P > 0.05).