Cell migration imaging and its functional analysis

In this study, a new type of cell-cultivation system based on laser processing has been developed for the on-chip cultivation of living cells. We introduce a "laser cell-chip". A sheet prepared from epoxy resin was processed by KrF excimer laser (248 nm, 1.6 J/cm²) for preparation of microgrooved surfaces with various groove width, spacing, and depth. A laser cell-chip can make kinetic studies of cell migration depending on the concentration gradient of a chemoattractant. In this study, megakaryocytes were used for the migration on a groove of laser cell-chip by the concentration gradient of the stromal cell derived factor 1 (SDF-1/CXCL12). SDF-1/CXCL12 plays an important and unique role in the regulation of stem/progenitor cell trafficking. A megakaryocyte was migrated on a groove of laser cell-chip depending on the optical concentration gradient of SDF-1/CXCL12. However, SDF-1-induced cell migration was inhibited by the pretreatment of phosphatidylinositol 3-kinase (PI3K) inhibitor, wortmannin and LY294002, suggesting that PI3K is likely involved in SDF-1-induced megakaryocyte migration. It is concluded that "laser cell-chip" was useful for the screening assay for migratory/antimigratory compounds.