New Population Of Adult Stem Cells Found In Blood Vessels
In a promising finding for the field of regenerative medicine, stem cell researchers at Children's Hospital of Pittsburgh of UPMC have identified a source of adult stem cells found on the walls of blood vessels with the unlimited potential to differentiate into human tissues such as bone, cartilage and muscle.
The scientists, led by Bruno Peault, PhD, deputy director of the Stem Cell Research Center at Children's Hospital, identified cells known as pericytes that are multipotent, meaning they have broad developmental potential. Pericytes are found on the walls of small blood vessels such as capillaries and microvessels throughout the body and have the potential to be extracted and grown into many types of tissues, according to the study.
"This finding marks the first direct evidence of the source of multipotent adult stem cells known as mesenchymal stem cells. We believe pericytes represent one of the most promising sources of multipotent stem cells that scientists have been searching for in the quest to make regenerative medicine possible," Dr. Peault said. "The encouraging aspect of this source is that blood vessels are the one structure that all tissues in the human body have in common. These cells can be extracted easily and painlessly from convenient sources such as fat tissue, dental pulp, umbilical cord and placental tissue, then grown in culture to large numbers and, possibly, re-injected into the patient to heal a broken bone, a failing joint or an injured muscle."
Results of the study are published in the September issue of the journal Cell Stem Cell.
In their laboratory in the John G. Rangos Sr. Research Center, researchers were able to identify pericytes in all human tissues they analyzed, including muscle, fat, pancreas, placenta and many other samples. Through purification in the lab, these pericytes could then be coaxed into becoming whatever type of tissue the scientists desired. For instance, the researchers took pericytes from the pancreas and then reinjected them into an injured muscle. The cells immediately began regenerating muscle tissue.
Dr. Peault's research includes the identification, characterization and purification of several categories of human stem cells: hematopoietic stem cells, mesenchymal stem cells, endothelial stem cells, and pancreas and respiratory epithelium stem cells. He also is a scientist at the McGowan Institute for Regenerative Medicine. Prior to joining Children's Hospital and McGowan, Dr. Peault served as research director at the Centre National de la Recherche Scientifique and department head at the Institut National de la Sante et de la Recherche Medicale in Paris.