3D printer uses sugar to create liver

BBC reveals.

Scientists have long been experimenting with the 3D printing of cells and blood vessels, building up tissue structure layer by layer with artificial cells.

But the synthetically engineered cells often die before the tissue is formed. The technology, in which a 3D printer uses sugar as its building material, could one day be used for transplants.

Although tissue engineering has made great strides in recent years, it is still impossible to recreate the complex 3D blood vessel networks that are present in naturally grown organs, Medical News Today notes.

Writing in the 1 July online issue of Nature Materials, researchers from the University of Pennsylvania and Massachusetts Institute of Technology in the US, say their 3D sugar printing method is a significant step in the right direction and is also free of some of the problems that arise when trying to make 3D tissue and its internal vasculature by other means.

For instance, one common approach that bioengineers use is to grow the tissue and its vascular network layer by layer, but this has a significant problem in that the nutrient fluid can push open the seams between the layers.

For the past decade, tissue engineers have looked for ways to build a 3D tissue in such a way that vessels are immediately available to feed growing cells, Chemistry World writes.

One way to create these vessels uses a tiny silicon template to pattern grooves in a sheet of cell-containing gel. Covering these cut outs with another sheet of engineered tissue creates enclosed channels. While these sheets can be layered to build up a tissue, the vessels only extend through the tissue in two dimensions, unlike the 3D network in our bodies.

Scientists can also print tissues using an inkjet printer to layer drops of cellular ink, leaving gaps for vessels. But they have to optimise the print settings for each cell type and supporting matrix.