Researchers Convert Human and Rat Bone Marrow Stem Cells to Neurons

Researchers at UMDNJ-Robert Wood Johnson Medical School developed the first successful procedure to convert cultured bone marrow stem cells exclusively into nerve cells. Ira B. Black, MD, chair of the Department of Neuroscience and Cell Biology, and his colleague Dale Woodbury, PhD, published the work in the August 15 issue of The Journal of Neuroscience Research. It was done in collaboration with Darwin Prockop and Emily Schwarz of MCP Hahnemann University in Philadelphia.

The research incorporates a number of important advances:

• The use of bone marrow cells provides a safe procedure, eliminating the high risk of obtaining stem cells from deep within the brain.

• Success with adult stem cells obviates the need for fetal tissue.

• The use of an individual's own (autologous) bone marrow cells eliminates the introduction of foreign cells and the need for toxic immunosuppressive drugs to avoid rejection.

• Rapid cellular growth and self-renewal in culture provides a virtually limitless source of cells and eliminates the need for immortalization and tumor-forming potential.

In addition, Black says that from a scientific point of view, the work suggests that presumed fixed gene mechanisms that determine cell fate can be changed by environmental signals.

"We are most excited about the future potential this finding holds for patients with spinal paralysis, stroke and degenerative brain diseases," he continues. "Research currently being conducted on rats with spinal paralysis suggests that stem cell transplants can encourage return of function.

"We know that neural stem cells migrate to areas in the brain that have been damaged. It appears that the cells can assume regional functions and actually improve function of the damaged systems."

For this study, the research team harvested the adult human and rat bone marrow stem cells and placed them in culture, where they were treated using the protocol developed specifically to induce conversion to neurons.

The researchers used time-lapse photography to study the differentiation process.

They identified specific neuronal gene products in the cells, confirming the conversion to neurons.

The team also performed a clonal analysis to determine whether each bone marrow stem cell had the capacity to generate neurons, or whether only a small sub-population participated.

"We found that each cell gave rise to neurons and new stem cells, providing a vast reservoir of source material," Black says. He and his team are already in the midst of the next stage of this research, which involves transplantation of these cells into the brain and spinal cord.