MTT cell proliferation assay

Cellular proliferation of PLum-AD and PLum-AI upon treatment with SB203580 or IL-6 was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cells were seeded in 96-well plates in triplicates and treated with SB203580 or IL-6 for 24, 48 and 72 hours. At each time point, cells were incubated with 10 μL of 5 mg/mL (in 1x PBS) MTT dye at 37°C, 5% CO₂ for 3 hours. Afterwards, media was aspirated and 100 μL of isopropanol was added to each well and incubated for at 37°C 15 minutes to solubilize the formazan crystals. Absorbance was measured on a Multiskan EX ELISA Reader at 595 nm. Cell proliferation was calculated using the percentage of the optical density (OD) ratio of treated cells relative to control (media without treatment). Data represents the average of three experiments.