EXTRACELLULAR MATRIX MODULATES SMOOTH MUSCLE CELL PHENOTYPE AND MIGRATION
Toshiro Ohashi, Yasufumi Hagiwara
Hokkaido University, Japan
Adherent cells are known to adhere to their extracellular matrix at focal adhesions, where actin filaments are indirectly connected to integrins via multiple proteins and integrins are in contact with the extracellular matrix mediating various cellular signals. Expression of integrins is very specific to the types of extracellular matrix such as fibronectin, vitronectin, collagen, etc. With this background, it is speculated that different types of extracellular matrix may modulate cell physiological functions. In this study, cell migration assays are performed with different types of extracellular matrix on smooth muscle cells. Cells were seeded with DMEM + 10% FBS in tissue culture dishes where a polydimethylsiloxane (PDMS)-made block was placed in the center of the dishes. After removing the PDMS block, cell migration was observed. Prior to cell seeding, the dishes were coated with fibronectin, vitronectin, and type I collagen. Under all the three conditions, cells migrated towards the space where the PDMS block had been placed. The total cell migration length for fibronectin was significantly higher than those for vitronectin and type I collagen. Since it was found that fibronectin could change smooth muscle cell phenotypes from contractile type to synthetic type, it is indicated that fibronectin-modulated smooth muscle cells could enhance cell migration. In summary, different types of extracellular matrix-mediated smooth muscle cell phenotype might modulate cell physiological functions possibly via integrin formation in a different manner.