*4.7. ELISA*

RAW264.7 cells were seeded onto a 6 well plate (2.0 × 10<sup>4</sup> per well) in α-MEM containing 10% FBS. On the following day, 0, 1, 2.5, and 5 μM FX were added to the culture medium and incubated with sRANKL or TNF/IL-6 for 4 days. MMP-9 detection was performed using commercial ELISA kits according to the manufacturer's instructions.
