Protein transduction domain of membrane penetrating peptide can efficiently deliver DNA and protein into mouse liver for gene therapy.

Background: The development of a harmless and efficient nonviral gene delivery system that can facilitate the penetration of nucleic acids through the plasma membrane is a key to successful gene therapy. The aim of this study was to test a nonviral gene transferring vector's function of delivering DNA into liver cells to provide an important clue for gene transfer in liver gene therapy.

Methods: The complex of DNA and DNA delivering protein was injected into mice through their tail veins. Then the mice were killed and their liver tissue was sectioned. The gene transferring results were detected using a confocal laser scanning microscope.

Results: Fluorescence analysis indicated that both DNA-membrane penetrating peptide (MPP) complex and DNA- hepatocyte specific receptor binding domain (HSRBD)-MPP complex could go into liver cells. The fluorescence value of liver cells in the DNA- HSRBD-MPP group was higher than that in the DNA-MPP group.

Conclusions: MPP can successfully deliver DNA and protein into cells, and MPP with a HSRBD can specifically deliver DNA into liver cells. These have laid a foundation for further study on the nonviral liver cell gene delivering system.