Researchers at the University of California San Diego have come across an efficient method to get human pluripotent stem cells to regenerate bone tissue.
The researchers have done this by feeding the cells adenosine, a naturally occurring molecule in the body. The stem-cell bone tissue helped repair cranial bone defects in mice without developing tumors or causing an infection.
The results could help patients with bone defects by opening up new regenerative treatments. Not only that, but a pure population of bone-building cells could be manufactured in an inexpensive way.
Pluripotent stem cells can become any type of cell in the body, such as muscle, heart or bone, through a process called differentiation. This can lead to therapeutic uses to repair or regenerate various tissues and organs, but it’s not a simple task to get this process going. There are many steps involved that make things costly and inefficient.
Not only that, but it’s been a challenge to produce these tissues and organs without teratomas, tumors that contain a variety of tissues found in different organs, from forming. Teratomas come from some of the pluripotent stem cells going rogue and differentiating uncontrollably.
The researchers, led by Shyni Varghese, a bioengineering professor at UC San Diego, showed control over the differentiation of human pluripotent stem cells into functional osteoblasts (bone-building cells) by adding adenosine to their growth medium. The osteoblasts built bone tissues with blood vessels, which was transplanted into mice with bone defects to form new bone tissues in vivo without any signs of teratoma formation.
Varghese’s team is currently investigating exactly how adenosine signaling promotes bone formation. They’ve attributed the signaling to a receptor on the stem cells’ surface called the A2bR receptor, which bines to adenosine. However, this mechanism appears to require further study from Varghese and her team.