Il 6 blocking antibody

An in vitro invasion assay was performed in triplicate using Growth Factor Reduced BD BioCoat Matrigel Invasion Chambers (BD Biosciences) according to the manufacturer’s instructions. Briefly, 3 × 10⁴ cells were seeded in the upper chamber with conditioned medium from PrSC treated with or without 100ng ml^-1 rFABP4, and the presence or absence of 10  μg ml^-1 of IL-8 blocking antibody, IL-6 blocking antibody, control goat IgG, or control mouse IgG (R&D Systems, Minneapolis, MN, USA). In the siRNA experiments, cells were treated with 50 nM FABP4 siRNAs for 24 hours before being seeded in the chambers. Subsequently, 20% FBS DMEM was placed in the lower chamber, followed by incubation for 24 hours. In some experiments, 1 × 10⁴ PrSC were seeded in the lower chamber with optimal medium. Sera from mice were collected, clarified by filtration (SLGV004SL; Millipore, Billerica, MA, USA), and used for ex vivo cell invasion assays. Briefly, 3 × 10⁴ cells were seeded in the upper chamber with medium containing 5% FBS or 5% mouse serum with or without 10  μg ml^-1 of IL-8 blocking antibody or 30 μM of BMS309403. DMEM with 20% FBS was placed in the lower chamber. Then, the non-invading cells in the upper chamber were removed and the membranes were stained with a Diff-Quik cell-staining kit (Sysmex, Kobe, Japan) to count the invading cells. The experiments were performed twice each in triplicate.