Department of Neurosurgery, Guangdong Academy of Medical Sciences, Guangdong General Hospital & Guangdong Institute of Neuroscience, Guangzhou, China.
Cell Mol Neurobiol. 2011 Jul;31(5):687-94. doi: 10.1007/s10571-011-9665-6. Epub 2011 Mar 9.
The purpose of the study was to examine the nanoscale distribution and density of the VEGFR-2 membrane receptor on the endothelial cell surface of glioma microvasculature. Immunofluorescence and atomic force microscopy combined with immunogold labeling techniques were used to characterize and determine the position of the glioma microvasculature endothelial cell surface receptor VEGFR-2. We aimed to indirectly detect the distribution of VEGFR-2 on the cell membrane at the nanoscale level and to analyze VEGFR-2 quantitatively. Immunofluorescence imaging showed a large amount of VEGFR-2 scattered across the endothelial cell surface; atomic force microscopy imaging also showed two globular structures of different sizes scattered across the endothelial cell surface. The difference between the average diameter of the small globular structure outside the cell surface (43.67 ± 5.02 nm) and that of IgG (44.61 ± 3.19 nm) was not statistically significant (P > 0.05). The three-dimensional morphologies of the small globular structure outside the cell surface and IgG were similar. The difference between the average diameter of the large globular structure outside the cell surface (74.19 ± 9.10 nm) and that of IgG-SpA-CG (74.54 ± 15.93 nm) was also not statistically significant (P > 0.05). The three-dimensional morphologies of this large globular structure outside the cell surface and IgG-SpA-CG were similar. The total density of these two globular structures within the unit area was 92 ± 19 particles μm(2). No globular structures were seen on the cell surface in the control group. The large globular structure on the surface of glioma microvascular endothelial cells was categorized as a VEGFR-2-IgG-SpA-CG immune complex, whereas the small globular structure was categorized as a VEGFR-2-IgG immune complex. The positions of the globular structures were the same as the positions of the VEGFR-2 molecules. A large amount of VEGFR-2 was scattered across glioma microvascular endothelial cell surfaces; the receptor density was about 92 per square micron.
本研究旨在研究胶质瘤微血管内皮细胞表面 VEGFR-2 膜受体的纳米级分布和密度。采用免疫荧光和原子力显微镜结合免疫金标记技术，对胶质瘤微血管内皮细胞表面受体 VEGFR-2 进行了特征描述和定位。我们旨在间接检测细胞膜上 VEGFR-2 在纳米级水平上的分布，并对其进行定量分析。免疫荧光成像显示大量 VEGFR-2 散布在细胞表面；原子力显微镜成像也显示两个大小不同的球形结构散布在细胞表面。细胞表面外小球形结构的平均直径（43.67 ± 5.02nm）与 IgG 的平均直径（44.61 ± 3.19nm）之间的差异无统计学意义（P > 0.05）。细胞表面外小球形结构和 IgG 的三维形态相似。细胞表面外大球形结构的平均直径（74.19 ± 9.10nm）与 IgG-SpA-CG 的平均直径（74.54 ± 15.93nm）之间的差异也无统计学意义（P > 0.05）。细胞表面外大球形结构和 IgG-SpA-CG 的三维形态相似。单位面积内这两种球形结构的总密度为 92 ± 19 个颗粒 μm(2)。对照组细胞表面未见球形结构。胶质瘤微血管内皮细胞表面的大球形结构被归类为 VEGFR-2-IgG-SpA-CG 免疫复合物，而小球形结构则被归类为 VEGFR-2-IgG 免疫复合物。球形结构的位置与 VEGFR-2 分子的位置相同。大量的 VEGFR-2 散布在胶质瘤微血管内皮细胞表面；受体密度约为每平方微米 92 个。
