Feasibility of a polysaccharide isolated from Bletilla striata used as a gene vector administered through an interventional pathway

AIM: To research into the feasibility of a polysaccharide isolated from Bletilla striata as a gene vector administered through an interventional pathway. METHODS: Bletilla striata polysaccharide (BSP) was isolated from a Chinese medicinal herb Bletilla striata, from which we prepared the cationic BSP (BSP⁺) by reductive amination. We further tested the ability of the BSP⁺ to incorporate and protect plasmid DNA, and the ability of the BSP⁺/pDNA complex to transfect into HepG2 cells. Then, we investigated the transfected effect of the BSP⁺/pDNA complex in vivo using green fluorescence protein (GFP) gene as a reporter gene administered through the hepatic artery. RESULTS: The synthesized cationic Bletilla striata polysaccharide (BSP⁺) incorporated and protected plasmid DNA to avoid enzymolysis by DNase. The transfection ratio was lower in the liposome group than in BSP⁺ group (28.87% ± 3.27% vs 36.64% ± 6.87%, P < 0.05). The BSP⁺/ pDNA complex was transfected into HepG2 cells in vitro and host cell in vivo. CONCLUSION: The BSP⁺/pDNA complex could target transfect into liver cell in vivo when administered through the hepatic artery using the interventional method, which could produce a marked effect as a new-type polycation gene vector in gene therapy.