(a) Fluorescent microscope images of osteoblasts two days after transfection with MC encoding for GFP using the same transfection conditions as used for BMP-2. Transfection efficiency approximately 15%, as determined by GFP+ cells per high power field (b) Western blot and quantification of BMP-2 protein expression by osteoblasts transfected with MC encoding for BMP-2 relative to GFP MC (**p<0.01). Data are normalized to β-actin expression. (c, d) qRT-PCR for BMP-2 expression on day 0 (***p<0.001) and osteocalcin expression on day 0 (**p<0.01), day 7 (**p<0.01), and day 14 (*p<0.05) following osteoblast transfection with MC encoding for BMP-2 or GFP. Data are presented as mean±standard deviation and all data are normalized to GFP MC day 0, with n=3 wells for each group. Bright-field images of Alizarin Red stained osteoblasts 14 days after transfection with MC encoding for (e) GFP or (f) BMP-2. (g) Quantification of Alizarin Red stained osteoblasts (h) demonstrating amount of extracellular mineralization after 14 days in vitro (*p<0.05). Data are presented as mean±SD, n=3.