Bone marrow stem cells can regenerate brain tissue, say researchers

DRAMATIC evidence that adult bone marrow cells can be used to regenerate neurons in humans was reported by scientists yesterday.

Researchers found marrow stem cells had transformed into brain tissue in three women.

The discovery points the way to using adult stem cells to treat degenerative brain disorders such as Parkinson’s disease.

Using cells from a patient’s own bone marrow would avoid the ethical objections to treatment with embryonic stem cells.

Stem cells are immature “master” cells that can be programmed to develop into different kinds of tissue.

Those extracted from early-stage embryos have the potential to become any type of cell in the human body. But using them entails cannibalising an embryo, which many people find unacceptable.

Previous research has suggested that, in some circumstances, adult bone marrow stem cells could be employed instead of embryonic stem cells.

Transplantation of human bone marrow cells has generated new nerve cells in the brains of mice. And a recent study showed adult marrow cells can be used to build new tissue in the cheeks of female patients.

For the new study, scientists in Florida examined post-mortem brain tissue from three women who received bone-marrow transplants to treat leukaemia.

All the transplants had come from male donors. The researchers found cells containing a Y chromosome, identifying them as of male origin, were present in the brains of all three women up to six years after their transplants.

In the survivor who lived longest, three types of brain tissue had the Y chromosome, including neurons.

The only place the Y chromosome cells could have come from was the bone marrow received from the male donors.

Dr Edward Scott, from the University of Florida Shands Cancer Centre in Gainsville, who led the team that reported the findings today in The Lancet medical journal, said: “This study suggests that bone marrow could be used as a therapeutic source of readily harvestable cells for the regeneration of nerve cells, with potential application to various neurodegenerative diseases and traumatic central nervous system damage.”