Proliferation and differentiation of rat bone marrow stromal cells on poly(glycolic acid)-collagen sponge

We studied the effects of dexamethasone ( Dex) and basic fibroblast growth factor ( bFGF) on proliferation and differentiation of rat bone marrow stromal cells ( RBMSCs), using three scaffolds: collagen sponge, poly( glycolic acid) ( PGA)-collagen sponge, and PGA-collagen ( UV) sponge. RBMSCs were seeded into the sponges, and cultured in primary medium, primary medium with Dex, and primary medium with bFGF and Dex. Three weeks after cultivation, we examined alkaline phosphatase ( ALP) activity and cell number in the sponges, and also performed macroscopic, light microscopic, and scanning electron microscopic ( SEM) observations. Collagen sponge shrank considerably, but PGA-collagen and PGA-collagen ( UV) sponges maintained most of their original shape. PGA-collagen ( UV) sponge supplemented with bFGF and Dex together had the highest ALP activity and cell number, followed by PGA-collagen sponge. Although collagen sponge showed cell proliferation only on the surface, the other two sponges showed cell proliferation in the interior. SEM showed the best cell attachment to PGA-collagen ( UV) sponge in the presence of bFGF and Dex, followed by PGA-collagen sponge. In conclusion, PGA-collagen ( UV) and PGA-collagen sponges proved to be much more useful as scaffolding for bone regeneration when combined with bFGF and Dex.