RESUMEN
The amphiphilic alpha-helical peptide, Td3717, is a bi-functional synthetic peptide that acts as both a polycation for DNA binding and a ligand for targeted delivery to tumor cells. Td3717 forms a stable complex with plasmid DNA, and the complex maintained high transfection efficiency after storage at 4 degrees C for six months and after four freeze/thaw cycles. During the storage and freeze/thaw cycling, the particle size of the DNA/Td3717 complex remained less than 100nm. The size of the complex is an important factor for its internalization into cells via the endocytosis pathway; therefore, the stability of the particles will strongly contribute to high transfection efficiencies after storage and repeated freezing/thawing.
Asunto(s)
Proteínas Portadoras/química , Proteínas Portadoras/metabolismo , ADN/química , ADN/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Transfección/métodos , Secuencia de Aminoácidos , Animales , Proteínas Portadoras/síntesis química , Proteínas Portadoras/genética , Células Cultivadas , Chlorocebus aethiops , ADN/genética , Endocitosis , Congelación , Haplorrinos , Datos de Secuencia Molecular , Estructura Secundaria de Proteína , Manejo de Especímenes , Células VeroRESUMEN
A cationic peptide, Td3701, which was derived from factor VIII that has affinity with phosphatidylserine (PS), showed efficient transfection ability for cells that express PS on the cell surface. PS is exposed on tumor cell surfaces therefore we have focused on PS as the target molecule for tumor specific gene delivery. In this article, to improve transfection efficiency and specificity in targeting tumor cells, some amino acid residues of Td3701 were replaced. The resulting peptide, Td3717, shows higher transfection efficiency (more than 30 times that of Td3701). The transfection efficiency was dependent on the amount of PS on the cell surface, suggesting that Td3717 bound with plasmid DNA could recognize PS on the cell surface. Td3717 is expected to be useful as an efficient gene carrier molecule specific to PS-presenting tumor cells.
Asunto(s)
Técnicas de Transferencia de Gen , Vectores Genéticos/metabolismo , Péptidos/química , Péptidos/metabolismo , Fosfatidilserinas/metabolismo , Secuencia de Aminoácidos , Animales , Línea Celular Tumoral , Chlorocebus aethiops , Vectores Genéticos/genética , Humanos , Datos de Secuencia Molecular , Péptidos/síntesis química , Péptidos/genética , Células VeroRESUMEN
Since phosphatidylserine (PS) is known to translocate to the external face of the plasma membrane when the cell membrane becomes disordered, we decided to focus our attention on PS as a target molecule for gene delivery. In this paper, the novel peptide Td3701 was designed, synthesized, and characterized for its physico-chemico-biological properties. Td3701 simultaneously exhibited both characters as a DNA carrier and a sensor probe for active targeting, which seemed to be triggered by structural changes in the presence of PS. This is a very unique character among nonviral vectors, and it is believed that Td3701 could be used for selective gene delivery.