The aim of the present study was the direct covalent coupling of the epidermal growth factor receptor (EGFR)-specific monoclonal antibody (mAb) to the surface of poly(lactide)-co-glycolide (PLGA)-polyethylene glycol (PEG) nanoparticles in order to achieve a cell type-specific drug carrier system against pancreatic cancer. The PLGA-PEG-NH2 diblock copolymer was synthesized by coupling reaction via amide linkage between PEG-diamine and activated PLGA. PLGA and PLGA-PEG-NH2 nanoparticles loaded with gemcitabine were prepared using the double-emulsion solvent evaporation method. PLGA-PEG immunonanoparticles were prepared by glutaraldehyde mediated cross-linking method. The conjugated antibody was analysed by transmission electron microscopy and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE) analysis. Cell viability study was performed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and cell uptake study was performed on fluorescein isothiocyanate-loaded formulations using confocal microscopy. The PAGE results indicated that mAb integrity was remained intact in the formulations after conjugation. Biological activity was confirmed under cell culture conditions: antibody-conjugated nanoparticles showed specific targeting to EGFR-overexpressing MIA PaCa-2 cell lines as shown in fluorescence image using confocal microscopy. The obtained data provide the basis for the development of stable and biologically active carrier systems for direct targeting of tumour cells using antibody-conjugated PLGA-PEG nanoparticles. Direct covalent coupling of antibodies to nanoparticles using glutaraldehyde as a cross-linker is an appropriate method to achieve cell type-specific drug carrier systems based on PLGA-PEG nanoparticles and the anti-EGFR-decorated PLGA-PEG nanoparticles have potentials to be applied for targeted chemotherapy against EGFR positive cancers.

中文翻译：

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载有吉西他滨的PLGA-PEG免疫纳米颗粒用于胰腺癌的靶向化疗。

本研究的目的是表皮生长因子受体（EGFR）特异性单克隆抗体（mAb）与聚（丙交酯）-共-乙交酯（PLGA）-聚乙二醇（PEG）纳米颗粒表面直接共价偶联为了实现针对胰腺癌的细胞类型特异性药物载体系统。PLGA-PEG-NH2二嵌段共聚物是通过PEG-二胺与活化PLGA之间的酰胺键偶联反应而合成的。使用双乳液溶剂蒸发法制备了载有吉西他滨的PLGA和PLGA-PEG-NH2纳米颗粒。通过戊二醛介导的交联法制备PLGA-PEG免疫纳米颗粒。通过透射电子显微镜和十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（PAGE）分析了缀合的抗体。使用3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四唑鎓溴化物测定法进行细胞活力研究，并使用共聚焦显微镜对负载异硫氰酸荧光素的制剂进行细胞摄取研究。PAGE结果表明，结合后mAb完整性在制剂中保持完整。在细胞培养条件下证实了生物学活性：缀合抗体的纳米颗粒显示出针对过表达EGFR的MIA PaCa-2细胞系的特异性靶向，如使用共聚焦显微镜的荧光图像所示。获得的数据为开发稳定和具有生物学活性的载体系统提供了基础，该载体系统使用抗体偶联的PLGA-PEG纳米颗粒直接靶向肿瘤细胞。