A study has revealed that transplanted bone marrow cells can successfully regenerate damaged nerves and can be an important milestone in developing artificial nerves.
Scientists at the Kyoto University School of Medicine have shown that when transplanted bone marrow cells (BMCs) having adult stem cells are protected a 15mm silicon tube and nourished with bio-engineered materials, they successfully help regenerate damaged nerves. The research may in future be considered a breakthrough to develop artificial nerves.
The study was led by Tomoyuki Yamakawa, MD at the Kyoto University School of Medicine.
"We focused on the vascular and neurochemical environment within the tube," said Yamakawa
He added: "We thought that BMCs containing adult stem cells, with the potential to differentiate into bone, cartilage, fat, muscle, or neuronal cells, could survive by obtaining oxygen and nutrients, with the result that rates of cell differentiation and regeneration would improve."
The BMCs were nourished with bioengineered additives, such as growth factors and cell adhesion molecules. After 24 weeks these BMCs differentiated into cells with characteristics of Schwann cells (a variety of neural cell that provides the insulating myelin around the axons of peripheral nerve cells).
The new cells successfully regenerated axons and extended their growth farther across nerve cell gaps toward damaged nerve stumps, with healthier vascularity.
"The differentiated cells, similar to Schwann cells, contributed significantly to the promotion of axon regeneration through the tube. This success may be a further step in developing artificial nerves," explained Yamakawa.
The grafting of self-donated (autologous) nerve cells to damaged nerves has been widely practiced and considered the "gold standard." However, autologous cells for transplant are in limited supply.
Allologous cells, donated by other individuals, require the host to take heavy immunosuppressant drugs.
Artificial nerves being cultured from a variety of cells and transplanted to nerve damaged areas, have been considered as alternatives to nerve grafting.
Although, prior to this research, cells cultured for this purpose were usually not very successful in regenerating axons with adequate vascularity or length to bridge nerve gaps.
"This technique for implanting BMCs containing adult stem cells at damaged nerve sites as employed by the Kyoto researchers has opened up new possibilities for nerve regeneration," said Paul Sanberg, PhD, D.Sc., Distinguished Professor at University of South Florida Health and co-editor-in-chief of Cell Transplantation.
The study was published in the current issue of Cell Transplantation.