Bioengineers have developed an inkjet system that can direct how and where stem cells can grow, allowing the creation of multiple tissues from a single population of cells, researchers announced Sunday.

Carnegie Mellon University bioengineers and stem cell biologists from the University of Pittsburgh used the technique to direct muscle-derived stem cells from mice to differentiate into both muscle and bone cells.

"Previously, researchers have been limited to directing stem cells to differentiate toward multiple lineages in separate culture vessels," said Phil Campbell, research professor at Carnegie Mellon's Institute for Complex Engineered Systems.

"This is not how the body works; the body is one vessel in which multiple tissues are patterned and formed."

The ability to control the pattern and types of cellsis important if researchers are to engineer replacement tissues that might be used in treating disease, trauma or genetic abnormalities, the study said.

The researchers sprayed a complex pattern onto protein slides, using a "bio-ink"that could stimulate or inhibit growth factors in cells.

When the stem cells were placed on the slide in a culture dish, the cells differentiated into either bone or muscle cells depending on the bio-inkthey interacted with.

The technology is a first step "to learn more about not only the basic biology of how multiple cell types are patterned in the body … but also for translating adult stem cells into real therapies for patients in the future," said Carnegie Mellon researcher Julie Phillippi.

Embryonic stem cells have the unique potential to develop into different cell types to serve the body. Scientists see them as a key in creating treatments to repair damaged tissue and halt degenerative conditions such as Parkinson's disease.

The use of human stem cells obtained from embryos has remained a contentious issue around the world, because the embryos are destroyed in the process.

Under the Assisted Human Reproduction Act, scientists in Canada can only use embryos created by in vitro fertilization that are no longer wanted for reproductive purposes.