Fig. 8
Characterization of miRFP670nano in vivo. a Comparison of miRFP670nano with miRFP670 in vivo. Fluorescence (top row) and bioluminescence (bottom row) images of living mice injected with 3 × 106 HeLa cells expressing miRFP670 (left) and miRFP670nano (right). Cells were co-transfected with Rluc8 (miRFPs:Rluc8 plasmid ratio is 10:1). The fluorescence images were obtained with excitation at 640 nm and emission at 680 nm using IVIS Spectrum instrument 72 h after cell transfection. b Brightness of injected HeLa cells expressing miRFP670 or miRFP670nano as shown in a. Mean fluorescence intensity was normalized to mean bioluminescence intensity. Error bars, s.d. (n = 3 experiments). c Minimal amount of detectable miRFP670nano cells. Fluorescence (top row) and bioluminescence (bottom row) images of living mice injected with various quantity of HeLa cells expressing miRFP670nano. Left mouse was injected with 3 × 106 (left) and 106 (right) cells; middle mouse was injected with 106 (left) and 3 × 105 (right) cells; right mouse was injected with 3 × 105 (left) and 105 (right) cells. Cells were co-transfected with Rluc8 (miRFPs:Rluc8 plasmid ratio is 10:1). The fluorescence images were obtained with excitation at 640 nm and emission at 680 nm 72 h after cell transfection. d Transfection efficiency of injected HeLa cells obtained by FACS analysis. e Two-color imaging of miRFP670nano and miRFP720 in vivo. Fluorescence images of living mice injected with 3 × 106 HeLa cells expressing miRFP670nano (top row) and miRFP720 (middle raw) and its overlay (bottom raw) are shown. The fluorescence images were obtained with excitation at 640 nm and emission at 680 nm for miRFP670nano and with excitation at 675 nm and emission at 720 nm for miRFP720 72 h after cell transfection
