Kyoto University researchers have found a way to use human skin cells to produce new types of cells faster than using stem cells, according to a study published Thursday in the U.S. online science journal Plos One.

A team at the university's Center for iPS Cell Research and Application used the so-called direct reprogramming method, where genes are implanted into skin cells, to produce a different type with the characteristics of cartilage cells.

The technique is expected to help treat cartilage damaged by disease or injury by reducing the time needed to produce new cells. The other method involves using artificially created induced pluripotent stem cells, which can grow into any type of human body tissue but take longer to produce.

The team, including professor Noriyuki Tsumaki, introduced three genes — c-MYC and KLF4 (which are needed to create iPS cells) and SOX9 (needed to develop cartilage cells) — into the skin cells of a newborn using a virus.

Within two weeks, cells bearing the features of cartilage cells were formed, the study said.

When these cells were transplanted into mice, they subsequently formed cartilage tissue, the team said, adding that no tumor was observed.

It only takes about two months to produce a sufficient amount of cells to transplant — about half the time required for the iPS cell technique, the team said.

Another advantage over the iPS cell technique is that the direct programming eliminates the possibility of contamination occurring from undivided cells that can develop into tumors, Tsumaki said.

Direct programming, however, still has hurdles to clear, he said.

"There are problems for its application in regenerative medicine, such as the use of a virus for transporting genes, and we want to overcome them," Tsumaki said.