The approach represents a potential way to overcome hurdles in delivering cargo to the interiors of cells, where they could be used as an alterative technology for gene therapy, said Rashid Bashir, a researcher at Purdue University´s Birck Nanotechnology Center.
The researchers attached nanoparticles to the outside of bacteria and linked DNA to the nanoparticles. Then the nanoparticle-laden bacteria transported the DNA to the nuclei of cells, causing the cells to produce a fluorescent protein that glowed green. The same method could be used to deliver drugs, genes or other cargo into cells.
"The released cargo is designed to be transported to different locations in the cells to carry out disease detection and treatment simultaneously," said Bashir. "Because the bacteria and nanoparticle material can be selected from many choices, this is a delivery system that can be tailored to the characteristics of the receiving cells. It can deliver diagnostic or therapeutic cargo effectively for a wide range of needs."
"For gene therapy, a big obstacle has been finding ways to transport the therapeutic DNA molecule through the nuclear membrane and into the nucleus," he said. "Only when it is in the nucleus can the DNA produce proteins that perform specific functions and correct genetic disease conditions." When the cargo-carrying bacteria attach to the recipient cell they are engulfed by its outer membrane, forming "vesicles," or tiny spheres that are drawn into the cell's interior. Once inside the cell, the bacteria dissolve the vesicle membrane and release the cargo.
The method might be used to take images of diseased tissues by inserting a cargo of fluorescent molecules into tumours that are ordinarily too small to be detected, said Demir Akin, a research assistant professor of biomedical engineering who specializes in nanomedicine.
MEDICA.de; Source: Purdue University