Fig. 3: MGV-based MMUS imaging for monitoring fibrosis in a human lung organoid model.
From: Magneto-acoustic protein nanostructures for non-invasive imaging of tissue mechanics in vivo
a, Schematic illustration showing microinjection of MGVs into a lung organoid and detection of stiffness change. b, Bright-field and merged fluorescence images of GVs and MGVs in lung organoids. n = 2 biological replicates examined in one experiment. c, Bright-field, B-mode and MMUS images and quantification of microinjected lung organoids with MNPs, GVs and MGVs. P (left–right) = 0.00000061, 0.00000062. n = 6 biological replicates examined in one experiment. d, Experimental timeline of the preparation of MGV-microinjected lung organoid models and MMUS imaging. e,f, Bright-field, B-mode, MMUS images (e) and SBR quantification (f) of MGV-microinjected lung organoids (normal and two fibrosis models). Images were taken from day 5 to day 16 after fibrosis induction. Quantification was conducted using relative MMUS SBR signal normalized to the day 5 value in normal and fibrosis groups. For day 7–16, P (grey, left–right) = 0.008486, 0.136217, 0.240127, 0.028171; P (black, left–right) = 0.002438, 0.036369, 0.032499, 0.012792. n = 3 biological replicates examined in two experiments. g, H&E staining of organoid sections in normal and fibrosis groups. Red arrows indicate the localization of MGVs in the organoids. n = 1 biological replicate examined in two experiments. h,i, Bright-field, B-mode, MMUS images (h) and SBR quantification (i) of MGV-microinjected lung organoids in the normal group, fibrosis group (50 ng ml−1 TGF-β) and drug-treated fibrosis group (50 ng ml−1 TGF-β + 10 μM nintedanib). Images were taken from day 5 to day 13 after fibrosis induction. Quantification was conducted using relative MMUS SBR signal normalized to the day 5 value in different organoid groups. For day 7–13, P (salmon, left–right) = 0.518531, 0.009231, 0.000368; P (purple, left–right) = 0.667557, 0.063610, 0.005257. n = 7 biological replicates examined in one experiment. Min and max on the parula (MMUS) and grey (B-mode) colour bars represent 0 and 20,000 arbitrary units. All lines and error bars represent mean ± s.d., and significance was determined using one-way ANOVA with Tukey’s multiple-comparisons test in c,f,i: *P < 0.05, **P < 0.01, ***P < 0.001.
