BALTIMORE, Aug. 22 (UPI) -- Scientists have developed a gel laced with adult stem cells derived from bone marrow that appears to be capable of giving rise to cartilage in the body.
The research has been carried out with goat stem cells and although human testing may remain years away, it could lead to effective treatments for cartilage-destroying arthritis and other conditions, Jennifer Elisseeff, a biomedical engineer at Johns Hopkins University, told United Press International.
The technique consists of injecting a light-sensitive gel containing stem cells -- capable of giving rise to many different tissue types -- into regions of the body with damaged tissue. Once in the body, the gel is exposed to ultraviolet light, which causes it to harden and form a matrix upon which the cells can grow.
Preliminary research indicates the stem cells will develop into cartilage that could replace damaged tissue, Elisseeff said. The cells that have grown in the gel have all the characteristics of hyaline cartilage, the type that is destroyed in arthritis, she said.
Because the therapy uses adult stem cells derived from bone marrow -- and not the more controversial embryonic stem cells -- the cells could be extracted from the patient's own body. This will help avoid rejection of the tissue, which can happen when cells are transplanted from one person into another.
The research appears promising enough that the biotech company Genzyme has expressed interest in collaborating with Elisseeff and funding her research. Genzyme, of Cambridge, Mass., manufactures a cartilage-replacing product called Carticel, which involves taking cartilage cells from a patient's own body and growing them in the lab and then re-injecting them back into the patient.
"We still need a lot of research on the stem cell gel" to show that it replaces damaged cartilage and that the new tissue is viable and remains viable, Genzyme's Sue Long told UPI.
Long said the technique could be useful for replacing cartilage lost due to a traumatic injury but she doubted it could be used to treat arthritis. The reason for this is arthritis in a joint involves inflammation and other processes that make it inhospitable for the survival of cells.
Bob Langer, a biomedical engineer at MIT, told UPI the research looks "very promising in general for cartilage replacement." He said it is too early to tell if it will prove useful for treating arthritis.
Elisseeff's lab will soon begin testing the gel in knees of human cadavers. One of the main barriers is getting the gel to stick to the slippery cartilage surface in the knee, she said. But they have developed polymers that seem to overcome this, she said.
The stem cell gel could also be used to regenerate facial body parts for cosmetic reconstructive surgery, Elisseeff said. It would be useful for injecting underneath the skin to replace nose tissue, jawbone tissue lost to a tumor and cartilage in the tempero-mandibular or jaw joint, she said.
Christopher Williams, a plastic surgeon working in conjunction with Elisseeff, soon will begin experimenting with the gel in mice, she said. The stem cells also have been coaxed into becoming a type of cell called an osteoblast, which can give rise to bone.
Elisseeff said she has submitted the research for publication in a peer-reviewed journal but has not received acceptance yet.
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(Reported by Steve Mitchell, UPI Medical Correspondent, in Washington)
