Figure 5
From: Tumor-penetrating peptide for systemic targeting of Tenascin-C
Systemic PL3-AgNPs home to U87-MG tumors. (A) In vivo imaging of U87-MG s.c. tumor-bearing mice injected with Alexa-647-labeled PL3-AgNPs (upper row), or with non-targeted AgNPs (lower row). The fluorescence imaging was performed using IVIS Lumina Imaging System at pre-injection and at 5 h post-injection. Three mice per group were i.v. injected with AgNPs; images after spectral un-mixing are shown. Note elevated tumor Alexa-647 signal in mice injected with PL3-AgNPs at 5 h post-injection. (B) Quantification of tumor Alexa-647AgNP fluorescence at pre-injection and at 5 h time points. The signal is expressed as Average Radiant Efficiency [p/s]/[µW/cm²]. Error bars: mean ± SEM (N = 3); P-values were determined using two-way ANOVA Fisher’s LSD test (ns, P > 0.05; ****P ≤ 0.0001). (C) The PL3-AgNP green signal was quantified from representative images using Fiji ImageJ. Error bars, mean ± SEM (N = 3 mice per group); scale bars: 20 μm; p-value was determined using Student unpaired t-test, two-tailed; ***p ≤ 0.001; ****p < 0.0001. (D) Effect of TNC-C and NRP-1 antibodies on tumor accumulation of PL3-AgNPs. PL3-AgNPs alone, or in combination with anti-TNC-C or anti-NRP1 antibodies, or a cocktail of both antibodies were i.v injected into mice bearing U87-MG xenograft tumors. Mice were perfused through the heart with PBS/DMEM 5 h after injection and organs were collected for cryosectioning and confocal microscopy. Colors: PL3-AgNPs (green), CD31-positive blood vessels (red) and DAPI (blue).control, we confirmed that preincubation of the antibody with recombinant TNC-C resulted in reduced staining (Fig. S10).
