The live cells are buoyant, enabling the researchers to separate them with a centrifuge. Black and colleagues reported last August using stem cells from the bone marrow of adults to generate nerve cells, a finding that was itself considered stunning. Gage is part of a team that previously demonstrated that people grow brain cells throughout life, overturning the dogma that humans are born with all the brain cells they'll ever have. Palmer said one goal of the new work is to develop a reliable technique for growing an essentially unlimited source of cells for use in medical therapies for traumatic brain injuries such as stroke and degenerative diseases such as Parkinson's, Huntington's and Alzheimer's. People would be asked to donate their brains in the same way they're asked to donate their organs after death.
Gage has other ideas, as well.
By studying the cells in the laboratory, he hopes to learn what factors activate the cells and induce them to assume different jobs. The goal is to induce the changes inside a living brain, eliminating the need for a transplant. Philip Schwartz, coordinator of the Brain and Tissue Bank for Developmental Disorders at Children's Hospital of Orange County, acquired most of the brains for the research, tapping hospitals along the West Coast. Although the brains were donated ahead of time by patients with incurable diseases, Schwartz said the handling of the postmortem tissues varied broadly, and that no special instructions were given to preserve the tissues. The use of cells from dead bodies seems to sidestep the ethical controversy surrounding the use of stem cells from embryos and fetuses, although some scientists argue that research is needed in all manner of stem cells.