“…The cytotoxic effects on A549, RAW264.7, and THP-1 cells were assessed by performing the Cell Counting Kit-8 (CCK-8) assay following specific protocols (Beyotime, Shanghai, China). When the cells reached 80% to 90% confluence, the medium was discarded, and the cells were washed with PBS three times and cultured in the corresponding serum-free medium ( 48 – 50 ). Doxycycline (0 to 128 μg/mL) in combination with baicalein (2 to 250 μg/mL) was added to 96-well plates along with 1 × 10 4 cells, which were cultured for 24 h at 37°C.…”