Thursday, October 09, 2008
Stem Cell Progress Is In The Bag.
"Earlier studies showed promise using so-called spermatogonial cells from the testes of mice. The new study used cells taken from biopsied tissue from 22 different men undergoing various medical treatments. The men ranged in age from 17 to 81.The story says that men could benefit more from this new source than women because the derived cells would come from the man's own body.
"Researchers found that after a few weeks of growth, the cells could differentiate into various types of cells just like those taken from embryos." (Here.)
"The new type of stem cells could be useful for growing personalized replacement tissues, according to a study in Thursday's issue of the journal Nature. But because of their source, their highest promise would apply to only half the world's population: men."Presumably this means immune rejection is avoided. However, immune rejection remains a problem with embryonic stem cells.
"Following experiments with mice, Stanford University scientists have announced that stem cell therapies which use human embryonic stem cells (hESCs) have a high probability of failing because of immune rejection. In these studies, mice that were injected with hESCs exhibited an immune response which is at least as severe as that triggered by organ transplantation. Consequently, all the transplanted stem cells were killed by the immune system within a week." (Here.)Thus, it doesn't appear definitive at this time that testicle-derived stem cells would be inferior to those derived from embryos or that they could only be used in men. But perhaps the best solution to overcoming immune rejection will come from research on reprogramming ordinary cells derived from tissues common to both men and women into stem cells. (Here and here.)