Adult Stem Cells May Offer Hope to MS Patients

Milan, Italy -- Injecting adult stem cells into mice repairs damage similar to that seen in multiple sclerosis, according to Italian researchers who say their work could one day offer hope for treating the disease in humans.

Investigators at the San Raffaele Scientific Institute in Milan report in Thursday's issue of the journal Nature that brain stem cells injected into the brains or veins of mice with an experimental form of the disease repaired nerve damage and, in many cases, improved symptoms.

In multiple sclerosis, nerves in large parts of the brain and spinal cord lose their insulating myelin sheaths due to an abnormal immune system assault, which damages the conduction of electrical nerve impulses.

The resulting symptoms include muscle weakness, visual disturbances, lack of coordination, and abnormal skin sensations. About 1 million people worldwide have the disease, which occurs in twice as many women as men.

Dr. Gianvito Martino and Dr. Angelo L. Vescovi injected neural stem cells from adult mice into mice with an experimental form of multiple sclerosis.

Stem cells are immature cells that have the capacity to develop into a variety of mature cell types. Brain stem cells are now known to be present in adult brains, and in the study, the researchers used neural precursor cells collected from adult mice.

"Thirty percent of mice recovered, 70 percent improved significantly," Martino said at a press conference on Wednesday.

"The novelty of this study is the possibility to induce myelin repair in multiple areas of the brain and spinal cord by transplanting brain stem cells not only directly within the central nervous system, but also into the blood circulation."

Within 30 days of injection, the stem cells homed in on the damaged area and proceeded to mature into myelin-producing cells.

The researchers said that the stem cells reached damaged areas thanks to specific "adhesion molecules" on their surface, which allow them to sense danger signals, pass through the protective blood-brain barrier and repair damaged areas.

"We realized that the donated cells have a key to pass through the bloodbrain barrier and enter into the central nervous system. This was the  first step to other amazing discoveries," Martino told Reuters Health. "But there is more," he said. The results show that stem cells not only
repair damaged areas themselves. They also trigger naturally occurring myelin-producing cells to repair the lesions.

The researchers stressed that the work is at an early stage, but within two months, Martino and Vescovi plan to begin non-human primate studies. Potential therapeutic applications for humans might take five to 10 years, they said.

Source:   Reuters Health; April 16, 2003

Second Article....

New Research Shows Adult Stem Cells Could Fight MS, Alzheimers
Source:   Minnesota Daily; April 29, 2003

Minneapolis, MN -- A University of Minnesota research team has discovered new properties of adult stem cells that could eventually treat neurological diseases such as multiple sclerosis, Huntington's disease, Parkinson's disease and Alzheimer's disease. Their findings are published in the April 25 edition of Cell Transplantation.

Dubbed multipotent adult progenitor cells, these rare stem cells are responsible for producing new cells that have a particular body function, such as generating red or white blood cells.

Though still shrouded in mystery, these cells appear perhaps more useful and less controversial than embryonic stem cells, the only other stem cell variety known to generate all types of brain cells.

"One of the problems with embryonic stem cells is, when you transplant them, they often have a tendency to form teratomas -- uncontrolled growths of cells that develop into teeth, cartilage or hair, for example," said Walter C. Low, a University of Minnesota neurosurgery professor and the study's principal investigator. "This is something we would not want to see if we put stem cells into the brain."

Scientists are uncertain of the full capabilities of multipotent adult progenitor cells. Discovered only last year in Dr. Catherine Verfaillie's University of Minnesota lab, the cells' role in the body is unknown. Extremely rare -- on the order of one in every 1 million bone marrow cells -- they require complicated in vitro growth techniques that are still being refined.

There is also an ethical concern with human embryonic stem cells.

Since they come from human embryos, human embryonic stem cell use is restricted in most countries. Multipotent adult progenitor cells have no similar restrictions.

In the most recent experiment, researchers injected a single adult stem cell into early mouse embryos and allowed them to mature.

From days to weeks after birth, the mice were killed and examined. Based on earlier experiments, researchers expected to find new cells created by single stem cells throughout the mice. But most researchers were surprised when they examined the animals' brains.

"It was expected to find the cells there -- it was unexpected in the numbers that we found and how diverse they were," Keene said. "They were throughout the entire brain and fully incorporated as far as we could tell."

The transplanted stem cells produced not only neurons, the brain's primary communication cells, but also brain tissue cells and myelin-forming cells.

Myelin insulates nerves, allowing the conduction of impulses from one part of the body to another.

"These adult stem cells have the capability of developing into essentially all of the cells one finds in the mammalian brain," Low said. "We might be able to use them to form myelin-forming cells for patients with MS. We might be able to treat patients with Lou Gehrig's or maybe even Parkinson's patients."