Researchers at the University of California, Irvine have reversed Alzheimer's-like symptoms in a mouse model of the disease with injections of neural stem cells. The mice used in this study mimicked the human disease, showing learning and memory defects and accumulating both beta-amyloid plaques and tau protein tangles within the brain, the two hallmark pathologies of the disease. Mice that received injections of mouse neural stem cells performed significantly better in memory tests than mice that received control injections. The stem cells did not replace cells lost to the disease.
Researchers at the University of California, San Francisco have pinpointed a protein that is critical for maintaining a stem cell's full potential to self-renew and to differentiate. Stem cells lacking the protein were impaired in their ability to divide and make identical copies of themselves, called self-renewal. These cells also lost their capacity to differentiate into key cell types, such as cardiac muscle. The protein, Chd1, acts to keep chromosome strands loosely wound, which permits widespread gene activation in the cell's nucleus.
Researchers at the University of California, Los Angeles have found genetic differences that distinguish induced pluripotent stem (iPS) cells from embryonic stem cells. These differences diminish over time, but never disappear entirely. iPS cells are created when adult cells, such as those from the skin, are reprogrammed to look and behave like embryonic stem cells. But until now, scientists didn't know if the two types of stem cells were actually identical at a molecular level. This latest research shows that iPS and embryonic stem cells differ in which genes they have turned on or off.
Researchers at the University of California, Irvine have found that neurons derived from embryonic stem cells were able to repair some damage in a mouse model of multiple sclerosis. In people with MS, the immune system attacks the insulation â called myelin â that covers and protects neurons of the brain and spinal cord. The transplanted cells caused a response in the animals that allowed the myelin coating to be repaired on damaged cells. In humans, repairing the myelin would likely also repair the function of those nerves, bringing back feeling and motor control in people with MS.
Researchers at the University of California, San Francisco have designed a safer technique for reprogramming adult cells into a state that resembles embryonic stem cells. This method takes advantage of genetic molecules called microRNAs, which regulate the activity of genes. The original 2007 method for creating reprogrammed cells, called induced pluripotent stem (iPS) cells, relied on inserting four genes, some potentially tumor-causing, into the DNA of an adult cell such as a skin cell.
Researchers at the University of California, Los Angeles have matured induced pluripotent stem (iPS) cells into what appear to be normal motor neurons. This work shows that iPS cells can mature into cells that appear similar to those derived from human embryonic stem cells â a finding that has important implications for people hoping to create new therapies based on iPS cells. These cells are created by reprogramming adult cells back into a pluripotent state that resembles embryonic stem cells.
Researchers at the University of California, Davis have coaxed cells from the brain to mature into the minute hair cells in the ear that are required for hearing. For many people with hearing loss, these tiny hair cells have died, leaving people unable to sense vibrations caused by sound. Regrowing functional hair cells that will sway in response to sound and send appropriate signals to the brain has been a major goal for stem cell researchers.
Researchers at UC, Los Angeles have created cells that go on to form normal T cells out of human embryonic stem cells. What's more, these cells were grown in the absence of animal feeder cells, which are usually needed to sustain embryonic stem cells. Avoiding potential contamination by such feeder cells is an important step in generating cells that can be transplanted into people. The researchers describe a series of steps that drive human embryonic stem cells to begin developing as T cells.
Researchers at the Stanford University School of Medicine found that cells derived from human embryonic stem cells could repair damage in a mouse model of heart attack. The researchers first looked at which genes were active at every stage between the human embryonic stem cells and early heart muscle cells. The cells they implanted mirrored the genes that are active in the hearts of 20 week old fetal mice.
Researchers at UC, San Diego verified a suspect gene mutation in blood-forming stem cells was by itself necessary and sufficient to cause a class of severe blood diseases called myeloproliferative disorders. They then worked with a team of researchers from other academic institutions and from the San Diego pharmaceutical company TargeGen to conduct animal tests of a compound TargeGen had already isolated and shown to inhibit that same genetic pathway. As a result of this broad collaboration, human clinical trials for this potential therapy began in February, 2008.