WEDNESDAY, Feb. 1 (HealthDay News) -- Treating stroke patients
with stem cells taken from their own bone marrow appears to safely
help them regain some of their lost abilities, two small new
Indian researchers observed mixed results in the extent of
stroke patients' improvements, with one study showing marked gains
in daily activities, such as feeding, dressing and movement, and
the other study noting these improvements to be statistically
insignificant. But patients seemed to safely tolerate the
treatments in both experiments with no ill effects, study authors
"The results are encouraging to know but we need a larger, randomized study for more definitive conclusions," said Dr. Rohit Bhatia, a professor of neurology at the All India Institute of Medical Sciences in New Delhi, and author of one of the studies. "Many questions -- like timing of transplantation, type of cells, mode of transplantation, dosage [and] long-term safety -- need answers before it can be taken from bench to bedside."
The studies are scheduled to be presented Wednesday and Thursday
at the American Stroke Association's annual meeting in New
Stem cells -- unspecialized cells from bone marrow, umbilical
cord blood or human embryos that can change into cells with
specific functions -- have been explored as potential therapies for
a host of diseases and conditions, including cancer and
In one of the current studies, 120 moderately affected stroke
patients ranging from 18 to 75 years old were split into two
groups, with half infused intravenously with stem cells harvested
from their hip bones and half serving as controls. About 73 percent
of the stem cell group achieved "assisted independence" after six
months, compared with 61 percent of the control group, but the
difference wasn't considered statistically significant.
In the other study, presented by Bhatia, 40 patients whose
stroke occurred between three and 12 months prior were also split
into two groups, with half receiving stem cells, which were
dissolved in saline and infused over several hours. When compared
to controls, stroke patients receiving stem cell therapy showed
statistically significant improvements in feeding, dressing and
mobility, according to the study. On functional MRI scans, the stem
cell recipients also demonstrated an increase in brain activity in
regions that control movement planning and motor function.
Neither study yielded adverse effects on patients, which could
include tumor development.
But Dr. Matthew Fink, chief of the division of stroke and
critical care neurology at New York-Presbyterian Hospital/Weill
Cornell Medical Center, said that the therapy's safety is the only
thing the two studies seemed to demonstrate.
"The thing to keep in mind is that these are really phase one trials," said Fink, also a professor of neurology at Weill Cornell Medical College. "I'm concerned that people get the idea that now stem cell treatment is available for stroke, and that's not the case."
Fink noted that the cells taken from study participants' hip
bones can only be characterized as "bone marrow aspirates" since
the authors didn't prove that actual stem cells were extracted.
"They haven't really analyzed if they're stem cells and what they turn into when they go into circulation," he added. "The best way to look at this is, it's very preliminary . . . when patients come to me to talk about it, I'm going to tell them it's years away before we know if this is going to work."
Studies presented at scientific conferences should be considered
preliminary until published in a peer-reviewed medical journal.
The U.S. National Institutes of Health has more information on