Transplanting scalp cells shows promise for baldness.

Scientists transplanted scalp cells from one person to another and, for the first time ever, grew new hair on a human without the use of drugs. The approach could someday enable just about any head to sprout hair, researchers said. It also raises hopes of someday spurring the growth of new tissue or even whole organs inside patients, such as cartilage in arthritic joints. In the new work, scientists at Durham University in northern England transplanted cells from a male hair follicle and grafted them on to a woman_s arm. Within five weeks, the transplanted tissue - no bigger than the head of a pin - made a total of five fully grown hairs in the woman_s arm. Although the research was designed to test whether the graft would be rejected by the unrelated woman, the researchers were pleased by the surprising results. "It does show the potential of being able to induce new hair follicles in human skin which I don_t think has been done before," said study head Colin Jahoda. Jahoda said normally the foreign cells would be rejected by the recipient. But the scientists suspect the cells taken from the base of follicle may have some type of immune privilege which allows them to mix with foreign cells. So instead of being cast out by the woman_s immune system, the male cells interacted with her cells to create new follicles. "The cells have got instructions to tell other cells to create the structure," explained Jahoda. "These cells instructed the host cells to make a new follicle." DNA samples taken from the newly sprouted hair contained the Y male chromosome, proving that the new hair was from the man_s cells.
As would be epxected with male hair, the new hair was longer, thicker and darker than arm hair, but it combined some characteristics of both donor and recipient. Such success had been achieved before only in animal experiments.