In a promising finding for the field of regenerative medicine, McGowan Institute faculty member Bruno Péault, PhD (pictured), deputy director of the Stem Cell Research Center at Children’s Hospital of Pittsburgh of UPMC, and a team of stem cell researchers 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 Dr. Péault, professor in the departments of pediatrics and cell biology at the University of Pittsburgh, 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. Péault 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.”
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. Péault’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. Prior to joining Children’s Hospital and McGowan, Dr. Péault served as research director at the Centre National de la Recherche Scientifique and department head at the Institut National de la Santé et de la Recherche Médicale in Paris.
In addition to Dr. Peault, McGowan Institute faculty members Stephen Badylak, DVM, PhD, MD, professor in the department of surgery, a deputy director of the McGowan Institute, and Director of the Center for Pre-Clinical Tissue Engineering within the Institute, and Johnny Huard, PhD, professor in the departments of orthopaedic surgery, molecular genetics, biochemistry, bioengineering, and pathology, director of the Stem Cell Research Center, the Henry J. Mankin Endowed Chair in Orthopaedic Surgery Research, and deputy director for cellular therapy at the Institute, are authors on the paper.
In a preview of Dr. Peault’s manuscript, Dr. Arnold Caplan, Case Western Reserve University, notes that this is a “landmark paper which presents a large body of work that defines, refines, confirms, establishes, and validates both the in situ and in vitro links between adult mesenchymal stem cells and perivascular cells, summarily referred to as pericytes.”
Dr. Caplan also notes that “although my colleagues and I have been working with marrow mesenchymal stem cells for over 20 years…we and others have never performed a comprehensive and detailed comparison of the in situ and in vitro traits and pericytes. The team led by Bruno Peault provides a solid set of observations that clearly links the mesenchymal stem cells and the pericyte.”
Illustration: McGowan Institute for Regenerative Medicine.
Children’s Hospital of Pittsburgh of UPMC News Release (09/22/08)
Science Daily (09/22/08)
Genetic Engineering & Biotechnology News (09/22/08)
Pittsburgh Post-Gazette (09/23/08)
Bio: Bruno Péault, Phd
Bio: Stephen Badylak, DVM, PhD, MD
Bio: Johnny Huard, Phd
Abstract (Cell Stem Cell; Vol. 3, 301-313 (09/11/08))