With the help of biomimetic matrices, a research team has discovered how calcium phosphate can coax stem cells to become bone-building cells.
UC San Diego Jacobs School of Engineering professor Shyni Varghese and colleagues have traced a surprising pathway from these biomaterials to bone formation. Their findings will help them refine the design of biomaterials that encourage stem cells to give rise to new bone.
The researchers said their study may also point out new targets for treating bone defects and bone metabolic disorders such as major fractures and osteoporosis.
The materials are built to mimic the body’s own cellular niches, in which undifferentiated or “blank slate” stem cells from bone marrow transform into specific bone-forming cells.
“We knew for years that calcium phosphate-based materials promote osteogenic differentiation of stem cells, but none of us knew why,” Varghese said. “As engineers, we want to build something that is reproducible and consistent, so we need to know how building factors contribute to this end.”
The researchers found that when phosphate ions gradually dissolve from these materials, they are taken up by the stem cells and used for the production of ATP, a key metabolic molecule. An ATP metabolic product called adenosine then signals the stem cells to commit to becoming bone-forming cells.