Scientists at the University of Manchester in England are trying to develop a technique through whichwill spray live human cells onto a patient. Ideally, this would speed up the healing process because doctors could seed a patient with replacement tissue that would grow to the size and shape required. The seed cells could also be grown from a previously harvested sample from the patient, thereby reducing the chances of donor rejection.
Brian Derby, professor,
University of Manchester
So far, the Manchester group has employed the technique to spray (and grow) human fibroblasts and osteoblasts, the cells responsible for forming, respectively, muscle tissue and bone, according to Brian Derby, professor of material science at the University of Manchester. They have also grown bovine chondrocytes, or cartilage cells.
"We are interested in tissue engineering cartilage, bone and blood vessels. Skin is an application but not our main focus even if the press have picked it up," Derby said in an e-mail. "My guess would be bone replacement as the first application."
Doctors might start using these techniques in five to 10 years, he noted. More near-term applications could involve developing tools for the biotech industry. Similar inkjet research is being conducted in Japan and at Clemson University in South Carolina.
So far, the technique hasn't been tried on a living patient. Instead, researchers have sprayed live cells into "wells" containing nutrients. The cells land intact and multiply within the first 24 hours. Derby's group has also used the inkjets to create scaffolds--tiny, fibrous structures containing cells that help start and control tissue regeneration.
Different cell types can likely also be mixed, which in turn would allow doctors to mimic more complex tissue functions.
The group is working with Xaar, a British inkjet manufacturer, to refine the equipment for human cell delivery. The cells, delivered in droplets of fluid, fly at about one foot per second and can accelerate at about 1,000 G-forces.
"It is surprising that cells do survive these conditions but they appear to do so. This needs a lot more work to ensure that the cells are not altered in some way by the delivery process," he wrote.