Abstract

Polyamidoamine (PAMAM) dendrimer is an extensively studied polymer in the biomedical research because of its low polydispersity, distinct molecular structure, and surface functionalities. Generally, a high-generational PAMAM dendrimer is used for gene delivery because transfection efficiency is dependent on charge density; however, an increase in charge density induces disruption of the cellular membrane, and damage to the membrane results in cytotoxicity. In this study, we selected PAMAM generation 2 to reduce the cytotoxic effect and conjugated RRILH and RRLHL sequences, nuclear localization signals (NLS) derived from herpesviridae to PAMAM generation 2. The transfection efficiency of RRILH-PAMAM G2 and RRLHL-PAMAM G2 was similar to that of polyethylenimine (PEI) in Neuro2A, HT22, and HaCaT cells, whereas their transfection efficiency was much higher than that of PEI in NIH3T3 cells. RRILH-PAMAM G2 showed relatively lower cytotoxicity than did RRLHL-PAMAM G2 in all cell lines, but the transfection capacity of the two polymers was similar. Our study shows that low-generational PAMAM dendrimer conjugated with NLS sequences has potential as an alternative to PEI in gene delivery.

摘要

聚酰胺胺 (PAMAM) 树枝状聚合物因其低多分散性、独特的分子结构和表面功能而成为生物医学研究中一种广泛研究的聚合物。通常，高代 PAMAM 树枝状聚合物用于基因传递，因为转染效率取决于电荷密度；然而，电荷密度的增加会导致细胞膜的破坏，细胞膜的损伤会导致细胞毒性。在本研究中，我们选择了第 2 代 PAMAM 以降低细胞毒性作用，并结合 RRILH 和 RRLHL 序列、源自疱疹病毒科的核定位信号 (NLS) 到第 2 代 PAMAM。RRILH-PAMAM G2 和 RRLHL-PAMAM G2 的转染效率相似与 Neuro2A、HT22 和 HaCaT 细胞中的聚乙烯亚胺 (PEI) 相比，而它们在 NIH3T3 细胞中的转染效率远高于 PEI。RRILH-PAMAM G2 在所有细胞系中显示出比 RRLHL-PAMAM G2 相对较低的细胞毒性，但两种聚合物的转染能力相似。我们的研究表明，与 NLS 序列结合的低代 PAMAM 树枝状聚合物在基因传递中具有替代 PEI 的潜力。