Preparation of VEGF165 Multimodal Molecular Imaging Probes and Its Targeting Imaging
Studies in Vitro and in Vivo
YOU Xiaoguang1, PENG Mingli2, TU Rong1, WEN Lijun3
1. The First Affiliated Hospital of Hainan Medical University, Haikou Hainan 570102, China; 2. Northwest University, Xian Shaanxi
710127, China; 3. School of Pharmacy, Hainan Medical University, Haikou Hainan 571100, China
Abstract：Objective To build multimodal molecular probe CY5.5 VEGF165-Aptamer-USPIO targeting tumor vascular endothelial
growth factor 165 (VEGF165), and to observe its combining capacity with VEGF165 in vivo and in vitro. Methods USPIO and
CY5.5-VEGF165-Aptamer were connected using EDC and NHS crosslinking agent, and the binding ability between CY5.5-VEGF165-
Aptamer and VEGF165 in vitro was tested with enzyme-linked immunosorbent assay (ELISA). BEL-7402 oxter hepatic carcinomaburdened
rat model was built, and these model rats were divided into the experimental group and the control group. Tail-intravenous
injection of CY5.5-VEGF165-Aptamer-USPIO was designed in the experimental group, and CY5.5-USPIO was used in the control
group. Images were acquired in multiple point-in-time manner, and the fluorescence intensity was measured in the region of interest.
The similarities and differences between the two groups were observed. The experimental group and the control group were designed
to undergo MR scans and multiple point-in-time enhanced scanning, and the changes of optical and MRI signal intensity between the
two groups were observed. Results The physicochemical properties of CY5.5-VEGF165-Aptamer-USPIO probe met the requirement
of the contrast agent, and the perticle size was less than 30 nm. The intensity of saturation magnetization was 35 emus/g approximately,
and the emission peak of CY5.5 was around 707 nm. ELISA showed that CY5.5-VEGF165-Aptamer-USPIO could only combine
with VEGF165 rather than VEGF121. Fluorescence images showed that mild reinforcement occurred in 1 h after caudalis intravenous
administration of the rats in the experimental group, peak reinforcement occurred after 3 h, and the enhancement disappeared after
6 h. MRI images showed that tumor-bearing rats in the experimental group suffered significantly negative enhancement at 3 h, and
the enhancement disappeared at 6 h, whereas there was no enhancement effect of rats at the corresponding time points in the control
group. Conclusion CY5.5-VEGF165-Aptamer-USPIO can specifically bind to VEGF165 in vivo and in vitro, and it is expected to be
used for VEGF165 targeted fluorescent and MRI imaging in vivo.
尤晓光1，彭明丽2，涂蓉1，文丽君3. 靶向VEGF165多模态分子成像探针制备与体内外靶向成像研究[J]. 中国医疗设备, 2019, 34(4): 41-46.
YOU Xiaoguang1, PENG Mingli2, TU Rong1, WEN Lijun3. Preparation of VEGF165 Multimodal Molecular Imaging Probes and Its Targeting Imaging
Studies in Vitro and in Vivo. China Medical Devices, 2019, 34(4): 41-46.
