Fig 2: Characterization of MSCs derived from rat bone marrow and transfection efficiency of MSCs with pEF1/His C::IGF-1::EGFP. (A) Expression levels of surface markers in the isolated MSCs were measured by flow cytometry for CD29-FITC, CD54-PE, CD90-FITC, CD45-PE and CD49d-FITC. The red histograms represent staining with respective surface marker antibodies and the black histograms represent staining with isotype controls. (B) Prior to FACS, the transfection efficiency of MSCs with pEF1/His C::IGF-1::EGFP and the nonviral carrier PAM-ABP was ~20% (P4). (C) Following FACS, transfected MSCs were collected and the purity was increased to 95.1%. Therefore, approximately all MSCs expressed a green fluorescent signal and IGF-1. CD, cluster of differentiation; EGFP, enhanced green fluorescence protein; IGF, insulin-like growth factor; MSC, mesenchymal stem cells; FACS, fluorescence-activated cell sorting cell sorting; FITC, fluorescein isothiocyanate; PE, phycoerythrin.