BALTIMORE—Deep in the brain, buried in the hippocampus and subventricular zone, reside adult neural stem cells, cells that retain the ability to become other types of neural cells and could serve as possible treatments for ailments ranging from vision impairment to Parkinson's to spinal cord injuries. Doctors, scientists and patients, however, are understandably hesitant to go digging around for them, their location being "a great deterrent," Sally Temple, founder of the New York Neural Stem Cell Institute, said at the 2009 World Stem Cell Summit here on Wednesday.

Researchers, therefore, are anxious to uncover other, more accessible neural stem cell candidates. Temple and her team have turned their sights to the retinal pigment epithelium (RPE), a layer of tissue at the base of the retina that comes into being within 30 to 50 days of conception, before many other parts of the neural system differentiate. Cells from this area of the eye can be easily harvested from retinal fluid that is usually discarded during retinal surgery, she explained.

BALTIMORE—In the decades-long war on cancer, as of late, researchers had been making little progress in comparison to colleagues treating other conditions, such as cardiac or infectious diseases. "Cancer research has really plateaued out," William Matsui, an associate professor of oncology at Johns Hopkins University's School of Medicine, said at the 2009 World Stem Cell Summit here on Tuesday. But pushing cancer stem cell research "gives us a novel way to study cancer," said Matsui, who also runs a lab at the university's Sidney Kimmel Comprehensive Cancer Center.

Cancer and stem cells have had a fraught relationship—not in the least because of early concern that stem cell treatments could in fact spur on cancer through their encouragement of undifferentiated cell growth. But cancer stem cells themselves have gained a more solid toe-hold in the past several years as a potential new target for cancer research.

Thanks to a little mouse named Tiny, researchers have now shown that full, living mammals can be grown from so-called induced pluripotent stem cells—cells from an adult that act in many ways like embryonic stem cells. 

Xiao Xiao, as the rodent is called in its native Chinese, was one of dozens created from induced pluripotent stem cells (iPS cells) and born to a surrogate mother. The process is described in a study published yesterday in Nature (Scientific American is part of Nature Publishing Group).

Researchers used a virus to deliver four genes into fibroblast cells taken from adult mice, triggering the change to iPS cells. These cells were then implanted into an embryo that didn’t have the requisite genetic information for it to develop beyond a placenta. That these implanted embryos developed into full baby mice proved that these cells could indeed do all the work of natural embryonic stem cells.

The National Institutes of Health (NIH) today released draft guidelines that permit federal funding for research on stem cells from human embryos set to be discarded by fertility clinics.

Under the new regs, the agency would fund studies on embryos created in test tubes — but no longer needed — for reproductive purposes, adult stem cells and induced pluripotent stem cells (skin or other adult cells that are nudged back into their pluripotent state, when they have the potential to become any cell type). Fertility patients would have to consent to their leftover embryos being donated for research.

Patients recently diagnosed with type 1diabetes who received transplants of their own immune stem cells were able to go without insulin injections for nearly five years after the procedure, scientists report today.

In type 1 diabetes, the immune system attacks islet cells in the pancreas that the body depends on to make insulin, a hormone that converts glucose into energy. Treatment typically includes injections or infusions of insulin. Now, research in the new Journal of the American Medical Association shows that the transplant technique — autologous nonmyeloablative hematopoietic stem cell transplantation, in which a patient is infused with immune system stem cells from  his or her own blood — enabled 20 of 23 recipients to thrive without insulin injections for up to 58 months. Twelve were able to stay off insulin continuously, while the rest had to periodically receive treatment.

Think girls are born with all the eggs they'll ever have? New research in mice suggests that long-held notion may be false.

Chinese researchers, reporting in Nature Cell Biology, say they found stem cells in the rodents' ovaries that could be nudged into becoming eggs that produced offspring. Physicians — not to mention would-be moms wondering when it's too late to get pregnant — have operated on the assumption that the supply of eggs a girl is born with is all she'll ever have and that it depletes with age. If the new finding is  confirmed in humans, though, it could broaden infertility  treatments to include the extraction and stockpile of the stem cells for future use, or drugs that would stimulate the cells to become eggs, the Washington Post notes.

DOHA, QATAR—Futuristic health technologies often first benefit patients in the U.S. and Europe. Now an ambitious plan backed by high-flying entrepreneur Richard Branson to start a national public-private cord blood bank in the Arab emirate of Qatar might help to ensure that the evolving science of regenerative medicine will also be able to find applications quickly within the Middle East.

The newly formed Virgin Health Bank will collect and store stem cells drawn from the umbilical cords of infants, with the permission of their mothers. A portion of those cells will be banked for that infant’s future use in the event of medical need, with the remainder going to a national public bank for research and assistance to any patient with a matching tissue type.

WASHINGTON, D.C. (March 10, 2009)—Stem cells have long been touted as potential cures or treatments for a variety of ailments from paralysis to Parkinson's disease. After all, these cells (found in bone marrow, for instance, and also in human embryos, making their use a subject of much controversy) can potentially turn into a wide variety of cells with specific functions. Or, they can throw off proteins—such as growth factors—that help other cells grow. Stem cells injected into a paralyzed patient’s spine, for instance, might help regenerate nerve tissue.

But while the flexibility of these cells is the key to their usefulness, they might not be quite as flexible as we once thought, says Julia Dory Ransohoff, 17, one of 40 finalists in the Intel Science Talent Search here in Washington this week for the competition’s final rounds. (We've been on hand to live-Twitter and to profile a few projects, everything from Splenda in drinking water to whether parents should discuss their drinking with their kids to cellulosic ethanol.)

President Obama today lifted an eight-year-old ban on embryonic stem cell research, signing an executive order that he called "an important step in advancing the cause of science in America."

"We will vigorously support scientists who pursue this research," Obama said at a signing ceremony in the White House. "And we will aim for America to lead the world in the discoveries it one day may yield."

Obama's order ends former President George W. Bush's limit on federally funded embryonic stem-cell research to cell lines created before Aug. 9, 2001. Congress tried twice to reverse that ban, and his National Institutes of Health (NIH) director, Elias Zerhouni, urged an end to the restrictions, but Bush vetoed the legislation both times.

President Obama is reportedly set to sign an executive order Monday lifting the Bush administration ban on federal funding of embryonic stem cell research. The move is being heralded by scientists, who charge the limit has hobbled research efforts that hold the promise of new treatments and even cures for spinal injuries and debilitating disease such as Parkinson's, Alzheimer's and cancer.

CNN reports that the White House is planning an 11 a.m. ceremony to repeal President George W. Bush's executive order limiting federal funding to research on 21 cell lines extracted from embryos prior to Aug. 9, 2001. Researchers say that most – if not all – of those lines have been compromised or contaminated and are no longer suitable for research.