Transfection activity of polyamidoamine dendrimers having hydrophobic amino acid residues in the periphery
Transfection activity of polyamidoamine dendrimers having hydrophobic amino acid residues in the periphery
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DOI：
10.1021/bc049785e
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发表时间：
2005-01-01
影响因子：
4.7
通讯作者：
Harada, A
中科院分区：
文献类型：
--
作者：
Kono, K;Akiyama, H;Harada, A
我们设计了链末端带有苯丙氨酸或亮氨酸残基的聚（酰胺基胺）树枝状聚合物。因此，我们通过树枝状聚合物内部叔胺诱导的质子海绵效应和树枝状聚合物外围疏水氨基酸残基的疏水相互作用的协同作用，实现了细胞的高效基因转染。具有16、29、46和64个末端苯丙氨酸残基的树枝状聚合物通过胺封端的聚(酰胺基胺)G4树枝状聚合物和L-苯丙氨酸使用缩合试剂1,3-二环己基碳二亚胺的反应来制备。这些苯丙氨酸修饰的树枝状大分子对非洲绿猴肾细胞系CV1细胞的转染活性随着末端苯丙氨酸残基数量的增加而增加，但具有64个苯丙氨酸残基的树枝状大分子除外，其水溶性较差，在中性pH下很难与DNA形成复合物。然而，在弱酸性条件下，具有64个苯丙氨酸残基的树枝状聚合物与DNA形成复合物，从而实现高效转染。相反，L-亮氨酸残基的连接无法提高亲本树枝状聚合物的转染活性，可能是因为该氨基酸的疏水性相对较低。与一些广泛使用的转染试剂相比，苯丙氨酸修饰的树枝状聚合物表现出更高的转染活性和更低的细胞毒性。因此，苯丙氨酸修饰的树枝状大分子被认为是有前途的基因载体。
We designed poly(amidoamine) dendrimers with phenylalanine or leucine residues at their chain ends. Thereby, we achieved efficient gene transfection of cells through synergy of the proton sponge effect, which is induced by the internal tertiary amines of the dendrimer, and hydrophobic interaction by the hydrophobic amino acid residues in the dendrimer periphery. Dendrimers having 16, 29, 46, and 64 terminal phenylalanine residues were prepared by the reaction of the amine-terminated poly(amidoamine) G4 dendrimer and L-phenylalanine using condensing reagent 1,3-dicyclohexylcarbodiimide. Transfection activity of these phenylalanine-modified dendrimers for CV1 cells, an African green monkey kidney cell line, increased concomitant with the increasing number of the terminal phenylalanine residues, except for the dendrimer with 64 phenylalanine residues, which showed poor water solubility and hardly formed a complex with DNA at neutral pH. However, under weakly acidic conditions, the dendrimer with 64 phenylalanine residues formed a complex with DNA, thereby achieving highly efficient transfection. In contrast, the attachment of L-leucine residues was unable to improve the transfection activity of the parent dendrimer, probably because of the relatively lower hydrophobicity of this amino acid. The phenylalanine-modified dendrimer exhibited a higher transfection activity and a lower cytotoxicity than some widely used transfection reagents. For that reason, the phenylalanine-modified dendrimers are considered to be promising gene carriers.