Fig 1.
FAM-tLyP-1 uptake in U87MG cells in vitro.
U87MG cells were incubated with different concentrations of FAM-tLyP-1 (0.0, 1.0, 5.0, 10.0, 20.0, and 40.0μM). The uptake of FAM-tLyP-1 in U87MG cells increases slightly in a dose dependent manner. FAM-tLyP-1: green; original magnification: ×200.
Fig 2.
Blocking FAM-tLyP-1 uptake with non-conjugated tLyP-1.
The uptake of FAM-tLyP-1 in U87MG cells is dramatically inhibited by incubation with an excessive quantity of non-conjugated tLyP-1 peptide. FAM-tLyP-1: green; original magnification: ×200.
Fig 3.
Representative images of FAM-tLyP-1 uptake in tumor tissue after 1 h in the U87MG tumor model.
(A) The nuclei of tumor cells were visualized by DAPI staining. (B) Frozen sections under a fluorescent microscope. FAM-tLyP-1: green; (C) The same frozen sections as in B stained with anti-NRP-specific antibody. Original magnification: ×200; scale bars: 100μm.
Fig 4.
Uptake of FAM-tLyP-1 in tumor and normal organ tissues.
(A) Tumor and normal organ tissues were removed and examined for fluorescence 1 h after FAM-tLyP-1 was intravenously injected into U87MG tumor bearing mice. (B) Uptake of FAM-tLyP-1 and FAM-control peptide in tumor and normal brain tissue.
Table 1.
Comparing the tumor/non-tumor (T/NT) ratios of FAM-tLyP-1 and FAM-control peptide in the subcutaneous U87MG glioblastoma xenograft model.
Fig 5.
Uptake of FAM-tLyP-1 can be inhibited in vivo by tLyP-1 in the U87MG tumor model.
(A) In vivo fluorescent imaging showing intense uptake of FAM-tLyP-1 in tumor tissue without inhibition by tLyP-1. (B) Minimal uptake of FAM-tLyP-1 in tumor tissue following administration of a 10-fold excess of non-conjugated tLyP-1 peptide. Images taken 1 h after administration of FAM-tLyP-1 by intravenous injection.
Fig 6.
In vivo detection of glioma tumors using 18F-tLyP-1.
In vivo microPET/CT MIP images in the U87MG tumor model at 30 min (A), 60 min (B) and 120 min (C) after injection of 18F-tLyP-1. The uptake of 18F-tLyP-1 in the tumor is intense, while minimal uptake is seen in the brain. MIP: maximum-intensity image.
Fig 7.
Biodistribution of 18F-tLyP-1 in U87MG tumor models.
The biodistribution of 18F-tLyP-1 is shown at 60 min and 120 min after injection (n = 5 mice).