Show Scientists find a new source of stem cells Karen Kaplan Los Angeles Times Tunes Scientists have converted cells from human testes into stem cells that grew into muscle nerve cells and other kinds kinds' of tissue according to a study published Wednesday in hi the online edition of Nature The stem cells offer another potential alternative to embryonic stem cells for researchers who aim to treat diseases such as diabetes and Parkinson's by replacing damaged or malfunctioning cells with grown custom-grown replacements Scientists also have derived flexible adult stem cells from skin amniotic fluid and menstrual blood were created from sperm-making sperm cells obtained from testicular biopsies of 22 men They are theoretically superior to traditional embryonic stem cells because they can be obtained directly from male patients and used to grow replacement tissues that their bodies wont won't reject Sabine Conrad of the University of in f U I Germany and her colleagues wrote The cells also have an ethical advantage in that they do not require the destruction of human embryos Experiments in mice suggested that reproductive cells also known as germ cells were good candidates for making stem cells because they naturally express low levels of the genes that make embryonic stem cells so versatile said Renee Reijo Pera director of the Human Embryonic Stem Cell Research Center at Stanford University who was not involved in the study The German researchers obtained biopsies from men ages 17 to 81 They extracted the individual testicular cells and grew them in laboratory dishes After about three weeks some of the cells formed colonies that resembled embryonic stem cells the team reported They found that the so-called so stem cells grew nearly as fast h as embryonic stem cells and produced many of the specialized protein markers that are associated with embryonic stem cells Cells from eight of the patients were injected into mice where they grew into jumbles of tissue that included cartilage muscle nerve cells and other building blocks of glands and internal organs according to the study This would be a great way to produce stem cells said Kathrin Plath a researcher at atthe atthe atthe the Broad Center of Regenerative Medicine and Stem Cell Research at the University of California Los Angeles who was not involved in the study But she said it remains to be seen whether the stem cells are able to form as many kinds of functional cells as embryonic stem cells Reijo Pera said stem cells do not have a completely blank slate like embryonic stem cells or the reprogrammed skin cells known as induced stem cells 1 |