Purpose

We tested polyplexes of a diblock polymer containing a pH-responsive, endosomolytic core (dimethylaminoethyl methacrylate and butyl methacrylate; DB) and a zwitterionic Poly (methacryloyloxyethyl phosphorylcholine) (PMPC) corona for the delivery of plasmid DNA (pDNA) to glioblastoma cells.

Methods

We studied the physicochemical characteristics of the DNA polyplexes such as particle hydrodynamic diameter and surface potential. Cytocompatibility of free PMPC-DB polymer and pDNA polyplexes with U-87MG and U-138MG glioma cell lines were evaluated using the ATP assay. The transfection activity of luciferase pDNA polyplexes was measured using a standard luciferase assay. Anti-proliferative, apoptotic, and cell migration inhibitory activities of PMPC-DB/Interferon-beta (IFN-β1) pDNA polyplexes were examined using ATP assay, flow cytometry, and wound closure assay, respectively.

Results

PMPC-DB copolymer condensed pDNA into nanosized polyplexes. DNA polyplexes showed particle diameters ranging from ca. 100–150 nm with narrow polydispersity indices and near electroneutral zeta potential values. PMPC-DB/Luciferase pDNA polyplexes were safe and showed an 18-fold increase in luciferase expression compared to the gold standard PEI polyplexes in U-87MG cells. PMPC-DB/IFN-β1 polyplexes induced apoptosis, demonstrated anti-proliferative effects, and retarded cell migration in glioblastoma cells.

Conclusion

The results described herein should guide the future optimization of PMPC-DB/DNA delivery systems for in vivo studies.

中文翻译：

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用于基因传递的基于磷酸胆碱的两性离子聚合物的 DNA 复合物。

目的

我们测试了一种二嵌段聚合物的复合物，该聚合物含有一个 pH 响应、内涵体溶解核心（甲基丙烯酸二甲氨基乙酯和甲基丙烯酸丁酯；DB）和一个两性离子聚（甲基丙烯酰氧基乙基磷酸胆碱）（PMPC）电晕，用于将质粒 DNA（pDNA）递送至胶质母细胞瘤细胞。

方法

我们研究了 DNA 复合物的物理化学特性，如粒子流体动力学直径和表面电位。使用 ATP 测定评估游离 PMPC-DB 聚合物和 pDNA 复合物与 U-87MG 和 U-138MG 胶质瘤细胞系的细胞相容性。使用标准荧光素酶测定法测量荧光素酶 pDNA 复合物的转染活性。PMPC-DB/干扰素-β (IFN-β1) pDNA 复合物的抗增殖、凋亡和细胞迁移抑制活性分别使用 ATP 测定、流式细胞术和伤口闭合测定进行了检测。

结果

PMPC-DB 共聚物将 pDNA 缩合成纳米级复合物。DNA 复合物的粒径范围从 ca。100–150 nm，具有窄多分散指数和接近电中性 zeta 电位值。PMPC-DB/萤光素酶 pDNA 复合物是安全的，与 U-87MG 细胞中的金标准 PEI 复合物相比，萤光素酶表达增加了 18 倍。PMPC-DB/IFN-β1 复合物可诱导细胞凋亡，表现出抗增殖作用，并延缓胶质母细胞瘤细胞的细胞迁移。

结论

本文描述的结果应指导未来优化 PMPC-DB/DNA 递送系统以进行体内研究。