- THURSDAY, Aug. 7 (HealthDay News) — Researchers in Massachusetts
have succeeded in generating several disease-specific stem cell lines
which should advance both research and, one day, treatment.

The lines will be made available to researchers around the world
through a Harvard Stem Cell Institute “core” facility being established at
Massachusetts General Hospital, institute co-director Doug Melton said
during a Wednesday teleconference.

The new lab is already up and running and is prepared to start shipping
lines as soon as a new paper is published in the Aug. 6 online edition of
Cell, added Dr. George Daley, senior author of the paper and a
principal faculty member at the institute.

“This is a broader and more important collection of degenerative
diseases for which there are no good treatments and, more importantly, no
good animal models,” Melton said. “The cells will allow researchers access
for the first time to cell types of interest, to watch the disease
progress in a dish, to watch what goes right or wrong. . . We'll see in
the years ahead that this opens the door to a new way of treating
degenerative disease.”

The cell lines will be distributed “virtually free,” Melton said, with
a nominal fee to cover costs.

Last week, another team of scientists from the institute announced that
they had transformed skin cells from patients with Lou Gehrig's disease
into motor neurons that are genetically identical to the patients' own
neurons. This will enable them to create unlimited numbers of cells to
study the disease process better.

Those scientists had originally planned to use somatic cell nuclear
transfer (SCNT) or “therapeutic cloning” for the feat. That process
involves removing the genetic material from a donated human oocyte and
replacing it with genetic material from the skin cells of patients. But
the approach has been hindered by political, ethical and other
obstacles.

Instead, those researchers took adult skin cells from two elderly
sisters with Lou Gehrig's disease and reprogrammed them into cells
resembling embryonic stem cells using a technique called induced
pluripotent stem (iPS) cells. Those stem cells were then transformed into
motor neurons.

The current paper in Cell describes a similar process, taking
cells from patients aged 1 month to 57 years and suffering from one of 10
conditions including Down Syndrome, Parkinson's, Huntington's disease,
muscular dystrophy and type 1 diabetes, and using iPS to produce
pluripotent, undifferentiated stem cells.

These cells, of course, will then have to be coaxed into tissues of
different types. “That is where all of the science will go on over the
next many, many years,” Daley said.

The recent successes will not likely obviate the need for controversial
stem cells, however, the scientists said.

“Even though the iPS methodology gives us a facile way for making
disease-specific lines, it does not eliminate the value or need for
continuing to study human embryonic stem cells,” Daley said. “Those are
really the gold standard for pluripotent stem cell types. They have no
genetic modifications and, at least for the foreseeable future, and I
would argue beyond that, are going to be extremely valuable tools. . .
Human embryonic stem cells allow you to ask questions that we never can
ask with iPS cells.”

The iPS method requires the use of viruses, limiting the therapeutic
potential of the lines.

“Whether or not we're going to be able to figure out how to do it
without viruses so we can use the cells therapeutically is, as of today,
an unanswered question,” Daley said. “I'm confident we're going to get
there and that within the next year or two, we will have several
strategies for reprogramming cells without viruses, and when that happens,
we may have cells in our hands that may be valuable for cell replacement
therapy.”

The number of lines ultimately generated will depend on a host of
factors.

“In these complex genetic diseases, we're so ignorant at the moment, we
don't even know if patients who get type 1 diabetes all get it the same
way. There could be 50 different ways to get type 1 diabetes,” Melton
said.

If there are 50 ways to get the disease, scientists are going to want
to develop more stem cell lines to reflect that variety. If there are only
one or two ways, then fewer lines will be needed.

More information

The National Institutes of Health has more on stem
cells.