Radioimmune and Inorganic Chemistry Section, Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-1002, USA.
Bioconjug Chem. 2010 Dec 15;21(12):2305-12. doi: 10.1021/bc100336b. Epub 2010 Nov 12.
A water-soluble amine-reactive PEGylated analogue of near-infrared emitting dye indocyanine green (5) was synthesized and used to label the anti-HER1 antibody panitumumab (Vectibix) at various equivalents. These conjugates were compared with non-PEGylated analogue conjugate products and the solution speciation analyzed with UV-vis spectrophotometry, size exclusion HPLC, and SDS-PAGE. PEGylation of the bioconjugates was successful in preventing aggregation in solution, a phenomenon observed with the non-PEGylated bioconjugates presumably due to the hydrophobicity of indocyanine green. Competitive radioimmunoassay demonstrated that the targeting moiety of the PEGylated bioconjugates was conserved. Fluorescence microscopy also demonstrated membrane binding of the bioconjugate to HER1-expressing A431 cells. Hence, these bioconjugates are suitable candidates for the in vivo optical imaging of HER1-expressing tumors.
一种水溶性胺反应性聚乙二醇化近红外发射染料吲哚菁绿(5)的类似物被合成,并用于标记抗 HER1 抗体帕尼单抗(Vectibix)的各种等价物。将这些缀合物与非聚乙二醇化类似物缀合物进行比较,并通过紫外可见分光光度法、尺寸排阻 HPLC 和 SDS-PAGE 分析溶液形态。聚乙二醇化生物缀合物成功地防止了溶液中的聚集,这一现象在非聚乙二醇化生物缀合物中观察到,可能是由于吲哚菁绿的疏水性。竞争性放射免疫测定表明,聚乙二醇化生物缀合物的靶向部分得以保留。荧光显微镜还表明,生物缀合物与表达 HER1 的 A431 细胞的膜结合。因此,这些生物缀合物是用于 HER1 表达肿瘤的体内光学成像的合适候选物。