Researchers at Swansea University are exploring the use of a novel 3D-bioprinting technology to make living tissue structures. This research is being focused not towards fuelling the excitement of organogenesis, but instead towards producing heterogeneous biological support tissues for use in reconstructive surgery. Currently this is focusing on producing tracheal tissues, which if successful may be an initial step towards producing tissues for abdominal and breast reconstruction, following cancer.
This research concentrates on using the natural self-organising properties of cells in order to produce a functional tissue which have measurable mechanical, metabolic and functional properties. Through utilising stem-cell differentiation this can lead to the fabrication of vascularised and innervated tissues. This 3D-bioprinting technique works by depositing a biologically active gel containing twenty million chondrocyte cells per millilitre, together with alginate, hyaluronic acid, transforming growth factor β1, antibiotics and gelatine. This biologically-centred method of bioprinting has been developed to allow for a wider level of experimentation at a both a University and clinical level, by building upon classic 3D tissue culture methods. It is hoped that this approach could see a greater adoption of this technology and further innovation in the short-term by enabling researches in the field to effectively produce experimental tissues, initially starting with cartilage.
A tracheal pre-tissue produced using 3D Bioprinting and the resulting Chondrocyte-based tissue after two days of maturation.
When a bioprinted pre-tissue is transferred to an incubator then this cell-based biogel matures into a tissue. Critically, hyaluronic acid has to be added to the biogel to limit the loss of proteoglycans during tissue maturation. This is critical towards the formation of structural and biochemical support material - extra-cellular matrix (ECM) during tissue maturation, and as the research team have found without ECM then a tissue will not form correctly.
3D-bioprinting used to generate heterogeneous tissues using a printable bioactive gel which matures into a tissue.
Although this is yet another step in the paradigm of bioprinting. It is hoped that in the long-term this research will develop bioprinting as a process that can be used to produce multiple tissue types for use operative repair materials or in the short-term for pharmaceutical trials. This next step in the development of this process could one day transform the field of reconstructive medicine which may lead to direct bio-engineering replacement human tissues on-demand for transplantation.
3D Bioprinting - Tracheal tissue
Dr. Dan Thomas is a research scientist, writer, editor and advocate for education. He holds degrees in Engineering and Science and is speaker on diverse topics such as sustainability, environmental engineering and nanotechnology.