Human embryonic stem cells (hESCs) are the primitive, undifferentiated ancestors of all the cells that make up an embryo. This characteristic, called pluripotency is the subject of interest in many recent pieces of research that use tissue engineering to grow tissue.
This application of hESCs also interested researchers from the University of Southampton who have recently published an article in Scientific Reports outlining their success in growing cartilage tissue from the precursor cells.
According to the research, the need for growing cartilage tissue arises from the non-regenerative characteristic of articular hyaline cartilage. This means that damage to the cartilage causes progressive wear leading to loss of movement, pain, and inflammation.
While previously, open surgery was the only way to treat articular cartilage damage, new techniques like using hydrogels laden with chondrocytes are gaining attention in the research community.
These techniques, however, require the use of scaffolding to shape the chondrocytes for repair. They are also usually derived from mesenchymal stem cells or human articular chondrocytes which are harvested through highly invasive procedures. These chondrocytes’ reparative capabilities also seem to deteriorate as time goes on.
Therefore, the team from Southampton focused on using easily available Human embryonic stem cells, which they stimulated into differentiation. The resultant cartilage tissue contained abundant chondrocytes, surrounded by an extracellular matrix that had a significant amount of Type II collagen.
The researchers let the tissue grow and checked its progress intermittently for 19 weeks. At 4 weeks, they found a tissue diameter of 1 mm. By the end of the 19 weeks, it grew to around 3mm.
What’s interesting is that the biomechanical properties of this synthesized tissue were comparable to the strength of natural articular cartilage. This was an important finding as it shows that the tissue is strong enough to replace articular cartilage.
Furthermore, the cartilage does not need scaffolding to shape it.
According to lead author Dr. Rahul Tare from the Faculty of Medicine at the University of Southampton:
“This tissue-based approach of replacing ‘like-for-like’ has the potential to constitute a step-change improvement in current cell-based surgical approaches for repairing damaged cartilage and improve long-term patient outcomes.”
The researchers are now looking forward to scaling up this tissue generation technique so that the tissues can be made commercially available to be used in articular cartilage replacement.
Source: University of Southampton