The effect of manufacturing methods of PLGA scaffold on the osteogenic differentiation of bone marrow stem cells

A key component in tissue engineering for bone regeneration is the scaffold that serves as a template for cell interaction and the formation of bone-extracellular matrix to provide structural support to the newly formed tissue. In this study, poly(L-Lactide-co-glicolide)(PLGA) scaffolds were prepared by solvent casting/salt-leaching, ice particle-leaching and gas-forming/salt-leaching. Cellular viability and proliferation were assayed by 3-(4,5-dimeth-ylthiazole-2-yl)-2,5-diphenyltetrazolium-bromide(MTT) test. Osteogenic differential cells were analyzed by ALP activity. Through RT-PCR analysis, we observed ALP and osteocalcin m RNA expression. Scaffold with BMSCs were implanted into the back of athymic nude mouse to observe in vivo behavior. Thin section were cut from paraffin embedded tissues and histological sections were stained by trichrome, immunohistochemical, von kossa staining. The cell proliferation and ALP activity of BMSCs in the scafoolds was the highest in the scaffolds using solvent casting/salt-leaching method. In RT-PCR results, in the all type of scaffolds observed specific gene expression of ALP, osteocalcin. By histological staining, we could observed collagen and calcification region in scaffolds by solvent casting/salt leaching method. Thus Solvent casting/salt-leaching method provided highly porous structure with good interconnections between each pores, which can support the surface of cell proliferation, differentiation. This result indicates that solvent casting/salt-leaching is useful for osteogenesis of BMSCs.