Fig. 3

Correlation between LS301 fluorescent signal with disease severity in individual limbs. C57BL/6 mice (n = 4 per group) with serum transfer arthritis (day 4 post disease induction) were injected intravenously with 6 nmol LS301. Whole body near-infrared fluorescence images were taken on the Pearl animal imaging system with λ = 820 nm. Regions of interest (ROIs) were drawn to quantitate LS301 near-infrared fluorescence in each limb (paws and ankles). Individual limbs of the mice were scored for paw edema and measured for ankle thickness by calipers. Fluorescence was plotted against clinical scores (A) and ankle thickness measurements (B). Pearson’s correlation coefficient was calculated by the standard equation using Microsoft Excel software