“Virgin” Stem Cells

Embryonic stem cells can theoretically heal any type of tissue, offering potential treatments for a wide range of diseases. However, because they come from fertilized eggs, which have the potential for human life, some believe that sacrificing them for medical use is unethical. Now researchers have found that stem cells extracted from unfertilized eggs could yield some of the same benefits, bypassing the ethical dilemma.

A phenomenon known as “virgin birth” occurs in nature in certain species of animals – from aphids and worms to sharks and Komodo dragons – through a process known as parthenogenesis, in which the female forces the eggs to divide without needing to be fertilized. Although this does not occur naturally in mammals, scientists in a laboratory setting have been able to coax human eggs into dividing for up to a few days. After that, they die off, but stem cells extracted while they are still viable act just like stem cells taken from fertilized eggs and are able to become any type of cell.

So far, six Parkinson’s patients have been injected with the parthenogenetic cells. Preliminary results show some improvements in symptoms, however the effectiveness of the treatment will need to be measured with a larger placebo-controlled trial. Because fertilized cells have different patterns of chemical “imprinting,” the “virgin” stem cells may not have the same capacity for regenerating. Regardless, their capacity for becoming dopamine-making neurons has been successfully demonstrated in animals, suggesting that symptoms associated with low dopamine levels in the brain (like tremors) should be able to be lessened using the new treatment.