[16] or exposed to
just phosphate buffered saline (PBS). After 12 and 24 h of the
cultivation, 50 ml of the cell culture medium was collected, added
into 96-well plates, and analyzed for luciferase activity using
Ready-To-Glow secreted luciferase reporter assay kit (Clontech)
according to the manufacturer’s instructions. The signals of
lucuferase activity were measured in a Victor3 multilabel plate
reader (PerkinElmer).