Cell Invasion Assay. This assay employs a simplified Boyden chamber-like design that consists of two chambers separated by a filter coated with BME or different extracellular matrix components. The cell suspension is placed in the top chamber and incubated in the presence of test media containing specific chemoattractants in the bottom chamber. Cells migrate from the top chamber through the coated filter pores to the bottom of the filter. Detection of cell invasion is quantified using Calcein AM. Cell dissociation/Calcein AM solution is placed in the bottom chamber to dissociate the migrating cells from the filter. Calcein AM is internalized by the cells, and intracellular esterases cleave the acetomethylester (AM) moiety. Free Calcein fluoresces brightly and is used to quantitate the number of cells that have invaded or migrated by comparison with a standard curve.