New Research Sheds Light On Early Embryonic Stem Cell Development Through First Time Birth Of Chimeric Monkeys From Stem Cells Taken From Two Separate Embryos

Conducted to gain a better understanding of the differences between natural stem cells residing in early embryos and their cultured embryonic stem cell  counterparts, the new work also determined that stem cell functions and abilities differ between primates and rodents.

The first cels studied were those that were totipotent – cells from the early embryo that have the ability to divide and produce all of the differentiated cells in the placenta and the body of an organism. These were compared with pluripotent cells – cells derived from the later stage embryo that have the ability to produce all body parts except those necessary for reproduction.

In mice, either totipotent or pluripotent cells from two different animals can be combined to transform into an embryo that later becomes a chimeric animal. However, the current research demonstrated that for reasons yet unknown, chimeric animals can only develop from totipotent cells in a higher animal model: the rhesus macaque. OHSU showed this to be the case by successfully producing the world's first primate chimeric offspring, three baby rhesus macaques named Roku, Hex and Chimero.

"This is an important development - not because anyone would develop human chimeras - but because it points out a key distinction between species and between different kinds of stem cells. This is knowledge that will impact our understanding of stem cells and their future potential in regenerative medicine," explained Shoukhrat Mitalipov, Ph.D., an associate scientist in the Division of Reproductive and Developmental Sciences at Oregon National Primate Research Center.

"Stem cell therapies hold great promise for replacing damaged nerve cells in those who have been paralyzed due to a spinal cord injury or for example, in replacing dopamine-producing cells in Parkinson's patients who lose these brain cells resulting in disease. As we move stem cell therapies from the lab to clinics and from the mouse to humans, we need to understand what these cells do and what they can't do and also how cell function can differ in species."

Adapted from the Oregon national Primate Research Center announcement.