Why shape matters in gene delivery

Gene therapies have been in development since the early 1970s, but delivery has always been an issue, and while viruses have been effective at getting the DNA inside cells, there have been concerns about health risks. Using microscopic polymer particles gets the DNA inside the cells without the issues of viral delivery, and changing the shapes of the nanoparticles alters how they travel through the body, according to research from Johns Hopkins and Northwestern universities. The results were published in Advanced Materials.

The researchers created nanoparticles with a core of DNA protected by a polymer shell. This shell is designed to shield the DNA from the immune system and then degrade inside the target cell, delivering its genetic payload. The cells can use the DNA as a template to produce the protein, replacing the missing or damaged protein.

"These nanoparticles could become a safer and more effective delivery vehicle for gene therapy, targeting genetic diseases, cancer and other illnesses that can be treated with gene medicine," said Hai-Quan Mao of Johns Hopkins' Whiting School of Engineering in a press release.

The way the particles move through the body depends on their shapes, and the researchers have used computer simulations to work out how the shapes form and how the ingredients of the particles can be manipulated to create the desired configuration. The shape also affects how the particles deliver DNA, and in animals, the team found that the worm-shaped particles triggered 1,600 times more gene expression in the liver cells than the other shapes.

"This means that producing nanoparticles in this particular shape could be the more efficient way to deliver gene therapy to these cells," said Mao.

- read the press release
- see the abstract