Figure 6.

Blood circulation, excretion and organ biodistribution profile of membrane-labelled B16F10 exosomes in melanoma-bearing NSG mice. Animals were injected with 1x10¹¹ [¹¹¹In]DTPA-Exo_B16 (0.5-1MBq). (A) Blood circulation profile of [¹¹¹In]DTPA-Exo_{B16 in} NSG mice. Blood (5 µl) was taken via tail bleeding at 2 min, 5 min, 10 min, 30 min, 1 h, 4 h and 24 h following intravenous injection of exosomes. (B) Excretion profile of [¹¹¹In]DTPA-Exo_B16 in NSG mice where urine and faeces were collected from the animals 24 h post-injection. For (A) and (B), the values are plotted in comparison with that of C57BL/6 presented in Fig. 5. (C) Organ biodistribution of [¹¹¹In]DTPA-Exo_B16 in NSG mice. Animals were culled at 1 h, 4 h and 24 h post-injection, perfused with saline and their organs were excised for analysis by gamma counting. Inset shows the zoomed-in tumour accumulation values for each group. (D) Comparison of organ biodistribution of [¹¹¹In]DTPA-Exo_B16 in C57Bl/6 and NSG mice 24 h post-injection, where inset shows zoomed-in tumour accumulation values for each group. Values are normalised to organ weight and expressed as mean ± SD, where n=3 for each group. For (C) and (D), statistical analyses were done on liver, spleen, kidneys and tumour (p*<0.05, p** < 0.01, p*** <0.001).