By embedding microfibrous sheets of an organic compound into a gelatin–nanohydroxyapatite matrix, researchers have synthesized a bone-regenerating composite scaffold1. This scaffold-aided differentiation and growth of bone cells could be used to replace bone tissues damaged by arthritis.

Nanohydroxyapatite is porous and its properties resemble those of natural bone-forming scaffolds. But, its brittleness makes it unsuitable for replacing worn-out load-bearing bone joints.

The researchers synthesized biodegradable microfibrous sheets from poly(L-lactic acid) and polyvinyl alcohol and incorporated these sheets into a gelatin–nanohydroxyapatite matrix. They then investigated the mechanical properties, cell infiltration, bone cell differentiation and bone regeneration of the scaffold by growing bone-forming human mesenchymal stem cells derived from adipose on it.

Embedding the microfibrous sheets into a gelatin–nanohydroxyapatite matrix reduced the scaffold’s brittleness. The scaffold accelerated the proliferation and differentiation of bone-forming stem cells and performed better than scaffolds lacking microfibrous sheets. The addition of the microfibrous sheets improved cellular infiltration towards the centre of the scaffold.

The scientists then surgically implanted the scaffold into defects in rabbit femur bone and found that the scaffold triggered cell infiltration and bone regeneration, so that bone defects healed within 4 weeks.

The researchers say that this porous, three-dimensional composite scaffold could potentially be used for bone regeneration in orthopaedics.