Stem Cells Getting Healthier
Over the past decade, stem cells have been a hot news item. Here are some late breaking news stories about them.
How they work: Researchers in the Netherlands found a new way to culture mouse embryonic stem cells in vitro. They found to their surprise, according to Science Daily, that the stem cells seem to be “on hold,”, their gene expression inhibited, rather than actively transcribing genes as previously believed. “From this state, the ES cells can efficiently specialize,” the article said.
Embryonic self-sacrifice: Researchers at the North Carolina School of Medicine found that embryonic stem cells will commit suicide rather than risk DNA damage. A protein called Bax, responsible for programmed cell death, is activated but kept in a safe place in the Golgi apparatus for the crucial days of embryonic development. If DNA damage occurs, Bax migrates to the mitochondrion, where it initiates cell death. PhysOrg titled its report, “Stem cells poised to self-destruct for the good of the embryo,” as if they will fall on their swords for the good of the organism rather than let DNA damage propagate.
Safe adult cells: Techniques for inducing pluripotent stem cells from tissues (iPS) continue to improve. PhysOrg reported that researchers at Johns Hopkins verified that iPS cells contain no more genetic changes than normal cells. This adds confidence that therapies developed from them will be safe, not adding cancer risk.
Skipping a step: According to Science Daily, researchers at Duke University were able to generate heart muscle tissue from scar tissue without going through a stem cell stage by programming microRNAs to turn scar cells back into heart muscle cells. By eliminating the need for a stem cell transplant, this promises to improve the hopes of damage repair for heart attack patients.
Dystrophy hope: It seems like forever that people have raised money for muscular dystrophy patients. Is any progress being made? Yes; according to PhysOrg, researchers at the University of Minnesota have demonstrated a therapy using iPS cells that has “been shown to be effective in the treatment of muscular dystrophy.” The mouse model sets the stage for human clinical trials. Researchers were able to deliver muscle progenitor cells from iPS cells. “Upon transplantation into mice suffering from muscular dystrophy, human skeletal myogenic progenitor cells provided both extensive and long-term muscle regeneration which resulted in improved muscle function,” the article said.
The good work continues to come from adult stem cells and iPS cells which, unlike embryonic stem cells (ES), are ethically sound (not involving the destruction of a human embryo). The ES promoters offer hope with hype. “Due to these unique properties, expectations for the use of ES cells in the clinic are high, but ES cells therapies have not yet been developed to full potential,” the first Science Daily article stated. If iPS cells do better with fewer problems and no moral concerns, why is there a dispute? Let human embryos develop into human beings, but let adult tissue cells be reprogrammed to heal.