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February 26th, 2012 
FAKE NEWS for the Zionist agenda SUNDAY, Feb. 26 (HealthDay News) — Researchers report that
they’ve isolated stem cells from adult human ovaries that can mature into
eggs that may be capable of fertilization.
The lab findings, which upend longstanding scientific theory, could
potentially lead to new reproductive technologies and possibly extend the
years of a woman’s fertility.
It was long believed that women were born with a lifetime supply of
eggs, which was depleted by menopause. But a growing body of research —
including a new paper from Massachusetts General Hospital — suggests egg
production may continue into adulthood. The study is published in the
March issue of Nature Medicine.
“Fifty years of thinking, in every aspect of experiments, of
interpreting the results, and of the clinical management of ovarian
function and fertility in women was dictated by one simple belief that
turns out to be incorrect,” said lead study author Jonathan Tilly,
director of the hospital’s Vincent Center for Reproductive Biology. “That
belief was the egg cell pool endowed at birth is a fixed entity that
cannot be renewed.”
Dr. Avner Hershlag, chief of the Center for Human Reproduction at North
Shore-LIJ Health System in Manhasset, N.Y., said the study is “exciting”
but emphasized the work is still very preliminary.
“This is experimental,” Hershlag said. “This is a beginning of perhaps
something that could bring in new opportunities, but it’s going to be a
long time in my estimation until clinically we’ll be able to actually have
human eggs created from stem cells that make babies.”
The same team at Mass General caused a stir in 2004 when it published a
paper in Nature reporting that female mice retain the ability to
make new egg cells well into adulthood.
In both mice and humans, the vast majority of egg cells die through a
process called programmed cell death, or apoptosis, the body’s way of
eliminating unneeded or damaged cells. For humans, that process is
dramatic. Female fetuses have about 6 to 7 million eggs at about 20 weeks’
gestation, a little more than 1 million at birth, and about 300,000 by
puberty.
Studying mice egg cells and follicles, the tiny sacs in which stem
cells become eggs, the Mass General researchers discovered something that
didn’t make mathematical sense.
Most prior research had focused on counting the healthy eggs in the
ovaries, and then made assumptions about how many had died from that,
Tilly said. But his lab looked at it the opposite way and focused on cell
death.
“We found far too many eggs were dying than could be accounted for by
the net change in the healthy egg pool,” Tilly said. “We reasoned that
maybe the field had missed something.” They wondered if stem, or precursor
cells, were repopulating the ovaries with new eggs.
Initially, the findings were met with skepticism, according to the
study authors, but subsequent research bolstered the conclusions.
Those included a 2009 study from a team in China, published in
Nature Cell Biology, that isolated, purified and cultured egg stem
cells from adult mice, and subsequently introduced them into mice ovaries
that were rendered infertile. The infertile mice eventually produced
mature oocytes that were fertilized and developed into healthy baby
mice.
Studies showing that women had the same capacity as mice were lacking,
however.
In this study, Tilly’s team used tissue from Japanese women in their
20s and 30s with gender identity disorder, who had their ovaries removed
as part of gender reassignment surgery.
The researchers isolated the egg precursor cells and inserted into them
a gene from a jellyfish that glows green, then inserted the treated cells
into biopsied human ovarian tissue. They then transplanted the human
tissue into mice. The green fluorescence allowed researchers to see that
the stem cells generated new egg cells.
Tilly said the process makes evolutionary sense. “If you look at this
from an evolutionary perspective, males have sperm stem cells that
continually make sperm. Because species propagation is so important, we
want to make sure it’s the best sperm, so don’t want sperm sitting around
for 60 years waiting to get used,” he said. It makes no sense from an
evolutionary perspective that “females will be born with all the eggs they
will have and let them sit there,” he noted.
Hershlag, meanwhile, said much remains to be overcome.
“Ultimately, in our field only one thing counts,” he said, “and that is
if you can make an egg that can make a healthy baby.”
More information
The U.S. National Library of Medicine has more on how human
embryos develop.
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