Figure 8.

In vitro labeling of TVECs with CL-PEG-MnFe₂O₄.

Notes: Prussian blue staining (200×) of control group (A), TVECs labeled with CL-PEG-MnFe₂O₄ (B), PEG-b-PCL-MnFe₂O₄ (C) and the mixture of CL-PEG-MnFe₂O₄ and CL 1555 peptides (D). It showed that the uptake of CL-PEG-MnFe₂O₄ was high, while few PEG-b-PCL-MnFe₂O₄ was engulfed into TVECs. Blocking CD105 with the free CL 1555 peptides also effectively reduced the amount of blue granules in the cytoplasm of TVECs. (E–H) showed the T2-weighted MR images of the four groups of cells. Correspondingly, the cells co-cultured with CL-PEG-MnFe₂O₄ (F) showed a more noticeable signal intensity drop than that with PEG-b-PCL-MnFe₂O₄ (G) and blocking with the free CL 1555 peptides (H).

Abbreviations: MR, magnetic resonance; PEG-b-PCL, polyethylene glycol-block-poly(ε-caprolactone); TVECs, tumor vascular endothelial cells.