For the first time human embryonic stem cells (hESCs) have been used in a 3D printing process and retained the properties that make them unique.
Researchers working in the field of 3D printing - in which differently shaped objects are produced from digital models - had already used other stem cells in experimental techniques. hESCs, which are prized for their ability to develop into any other kind of cell in the body, are fragile and had not previously been used.
But scientists at Heriot-Watt University in Edinburgh used the cells like components of the ink in a conventional printer to produce 'spheroids' of defined shapes and sizes. Control of the dimensions of the spheroids is important as hESCs require tightly regulated conditions in order to function correctly.
Dr Will Shu, who led the study, said that the technology was 'gentle enough to maintain high stem cell viability, accurate enough to produce spheroids of uniform size, and most importantly, the printed hESCs maintained their pluripotency - the ability to differentiate into any other cell type'.
The study reports that 99 percent of the cells tested were considered viable after printing. The cells were originally sourced from an embryonic kidney and from a well-known embryonic cell line. After growing in culture they were housed in a reservoir - an 'inkwell' of sorts - before being pumped through the valves of the printer.
One of the possible eventual applications of this kind of technology would be in producing tissue samples for drug development that would reduce the need for animal testing. Further down the line, Dr Shu adds, 'we envisage the technology being developed to create viable 3D organs for medical implantation from a patient's own cells, eliminating the need for organ donation, immune suppression and the problem of transplant rejection'.
Jason King, business development manager at Roslin Cellab, a biotechnology company working with the university research team, called the study a 'scientific development which we hope and believe will have immensely valuable long-term implications for reliable, animal-free drug-testing and, in the longer term to provide organs for transplant on demand'.
The research is published in the journal Biofabrication.