Artificial bone sculpted with unprecedented detail

The creating of artificial bone which precisely matches natural bone – down to the microscopic detail of the tiny structures vital for stem cell differentiation and bone regeneration – is a holy grail for orthopaedics. This could open doors to improved disease modelling, in vitro cell research on targeted therapies, and drug screening.

The New York-based researchers have published a study detailing a system which allows them to sculpt the exact structures of bone tissue from a biocompatible material, with features smaller than the diameter of a proton.

Cells exist in environments within the human body which control their behaviour and support tissue regeneration via certain morphological and chemical signals at the molecular scale. Bone stem cells are embedded in a matrix of fibres within a very complex bone structure, which had previously eluded replication using standard methods.

The platform on which the new system is based is known as bio-thermal scanning probe lithography (bio-tSPL). It involves taking a “photograph” of the natural bone tissue, and then using this as reference for producing a replica.

The researchers demonstrated that it is possible to scale up bio-tSPL to produce bone replica on a size useful for biomedical studies and applications and at an affordable cost. These structures can support the growth of new bone cells from the patient’s own stem cells, hinting at new stem cell applications with very broad research and therapeutic potential, such as improved orthopaedic implants.

“tSPL is a power nanofabrication method that my lab pioneered a few years ago, and it is at present implemented by using a commercially available instrument, the NanoFrazor,” said Professor Elisa Riedo, who led the study. “However, until today, limitations in terms of throughput and biocompatibility of the materials have prevented its use in biological research.

“We are very excited to have broken these barriers and to have led tSPL into the realm of biomedical applications.”

Its time and cost effectiveness, as well as the cell compatibility and reusability of the bone replicas, could make bio-tSPL an ideal platform for producing surfaces which perfectly mimic any biological tissue with unprecedented precision and detail.

Giuseppe Maria de Peppo commented: “I am excited about the precision achieved using bio-tSPL. Bone-mimetic surfaces, such as the bone reproduced in this study, create unique possibilities for understanding cell biology and modelling bone diseases, and for developing more advanced drug-screening platforms.

“As a tissue engineer, I am especially excited that this new platform could also help us create more effective orthopaedic implants to treat skeletal and maxillofacial defects resulting from injury or disease.”