doi:10.1038/nindia.2009.253 Published online 23 July 2009
Researchers have designed nano-sized non-viral carriers for DNA delivery to specific tumour cells1. The tiny carriers were made by mixing an organic compound with a polysaccharide. The carrier is less toxic and safer to ferry DNA to desired target cells.
A gene carrier loaded with DNA helps cross the cell barrier and relocates the DNA into the nucleus of target cells thereby expressing the desired protein with therapeutic roles. Though viral gene carriers are smart, they are not safe. In recent years, non-viral carriers such as liposomes and nanoparticles have drawn much attention.
The researchers chose polyethylenimine (PEI) as a safe non-viral carrier. On its own it is toxic for the cells. To overcome this, they designed nano-sized carriers by blending chondroitin sulfate (CS), a polysaccharide, with PEI thus making it compatible for cells.
The carriers delivered DNA successfully to various cultured cells, Ehrlich ascites tumour (EAT) in mice and cervical and liver cancer cells. The water-loving surface of the carriers prevents polymer aggregation and non-specific adhesion to the cell surface, resulting in lower toxicity.
"Since our technique for the preparation of non-viral gene carriers is simple, it should facilitate both basic and clinical research and a potential alternative to gene therapy of tumour," says lead researcher Kailash C. Gupta.
The authors of this work are from: Institute of Genomics and Integrative Biology (CSIR), Delhi University Campus; Institute of Nuclear Medicine and Allied Science, New Delhi; Department of Pharmaceutical Sciences, Dr. Harisingh Gour Vishwavidyalaya, Sagar, M.P. and Indian Institute of Toxicology Research, Lucknow, U.P., India