*2.1. Materials*

Pluronic® F68 and Tetronic® 908 were generously provided by BASF (Ludwigshafen, Germany). The pro-inflammatory cytokines (IL-1β, TNF-α) were obtained from Prepotech (Hamburg, Germany). The anti-SOX9 (C-20) antibody was purchased at Santa Cruz Biotechnology (Heidelberg, Germany) and the anti-type-II collagen (II-II6B3) antibody at DSHB (Iowa, IA, USA). Biotinylated secondary antibodies and the ABC reagent were obtained from Vector Laboratories (Alexis Deutschland GmbH,

Grünberg, Germany). Alcian blue 8GX was from Sigma (Munich, Germany). The Cell Proliferation Reagent WST-1 was obtained from Roche Applied Science (Mannheim, Germany).
