They look like nerve cells, and even act like them for a short time.
In fact, scientists at Duke University Medical Centre and a company called Artecel Sciences Inc think the cells they recently "grew" out of fat tissue left over from liposuction procedures could actually be nerve cells.
Growing totally different types of cells
"This is the first study in this field," says Dr Henry Rice, senior author of a paper appearing in the Biochemical and Biophysical Research Communications journal. "You don't want to overstate it, but it's pretty darn big."
Scientists had already succeeded in transforming human fat cells into cells of the same general category and embryonic origin - namely muscle, cartilage and other fat cells.
Neural cells, however, have a completely different origin than the cells found in human fat tissue.
"Basically, this is a big jump. We didn't know we could do this," Rice says. "What we have suggested is that we can differentiate cells into an entirely different lineage."
Other researchers have also managed to transform cells other than fat cells (for example, bone marrow cells) into nerve cells, but bone marrow cells are extremely difficult to harvest and therefore not a plentiful source.
"This is attractive because it's an alternative source of a similar cell, and America is not short of fat," Rice says. "There is tremendous potential to treat disease."
Helping nerve cells to re-grow
Human nerve cells are incapable of re-growing on their own. Right now, people suffering from spinal cord injuries, stroke, Alzheimer's disease and other conditions that involve death or damage to the neurons have no way of recovering.
"Once the injury happens, it's very hard to get cells to re-grow," says Rice, who is also a consultant to Artecel Sciences. "One strategy is to inject cells to do the cellular repair, but these cells are usually embryonic cells or a very rare population of true neural stem cells from deep in the brain, and both are impractical for clinical use."
The new technique, should it pan out in future research, would be clinically accessible. "Way down the road, if a person had a spinal cord injury, we could take some of their own fat, treat it, then put it back in. You wouldn't even have to worry about rejection," he says.
Creating sustainable cells
In this study, Rice and his colleagues took cells from human and mouse fat tissue, treated them with chemicals and growth factors and came up with something that behaves a lot like nerve cells. Although they can't be sure until they've put it into a human being and watched it function, these researchers are hopeful. First of all, the test-tube cells have a structure very similar to nerve cells. The investigators also demonstrated the presence in the cells of proteins that are found only in neurons.
After about four or five days, however, the newly differentiated cells started reverting to their old state of being. Within about two weeks, all the cells had died.
The newly grown cells would need to go through a whole series of higher-level tests to demonstrate they do indeed have the properties of neural cells, researchers say, and they'll have to prove themselves in animal models.
"It's interesting because it does demonstrate that there are sources that are easy to get to, such as fat tissue," says Paul Sanberg, director of the Centre for Ageing and Brain Repair at the University of South Florida College of Medicine in Tampa. "But it's important to see whether they can get a long-term demonstration, even in culture, and also whether they become different types of neurons."
"It's very early to say whether these cells really could be useful for neurodegenerative disease or stroke or anything like that," Sanberg adds. - HealthScout