The researchers used interferon (IFN) gamma to excite a certain group of multipotent stem cells to metamorphose into bone cells. Multipotent stem cells are immature cells that can grow into many, but not all, types of mature, specialized cells.
“We have identified a new pathway, centered on IFN gamma, that controls the bone remodeling process both in vivo and in vitro,” said Gustavo Duque, the study’s lead author and director of the Aging Bone Research Center at the Nepean Clinical School. “More studies are required to describe it more precisely, but we are hopeful that it could lead to a better understanding of the underlying causes of osteoporosis, as well as to innovative treatments.”
In the study, Duque and his team stimulated cultured stem cells to turn into osteoblasts, or bone cells, in vitro.
“We realized that this differentiation process involved IFN gamma-related genes, but also that these bone-cells precursors could both be stimulated by IFN gamma and produced IFN gamma,” said Duque, who is also an associate professor at the University of Sydney.
They then tested interferon gamma’s action in an animal, blocking the effect of the hormone by inactivating its receptors. Bone-density tests similar to the DXA scans used in humans then found that interferon-gamma-inactivated animals had a much lower bone mass than healthy animals. The researchers said this confirms that interferon gamma plays a key role in these stem cells’ differentiation into bone cells.
Since interferon gamma – or another molecule involved in its biochemical pathway – is crucial for bone growth, the door has now been opened for possible drugs to be formulated to remedy osteoporosis, once further research has illuminated the entire chemical process.