Biomedical Breakthroughs: Vascular Network Bioprinting

bioprintingThe ability to generate biological tissues using 3-D printing methods – aka. “bioprinting” – may one day help medical researchers and hospitals to create artificial, on-demand custom body parts and organs for patients. And numerous recent advancements – such as the creation of miniature kidneys, livers, and stem cell structures – are bringing that possibility closer to reality.

And now, according to a new study produced by researchers from the University of Sydney, it is now possible to bioprint artificial vascular networks that mimic the body’s circulatory system. Being able to bio-print an artificial vascular network would give us the ability to keep tissue and organs alive where previously it would not have been possible. The body’s vascular network enables it to transport blood and, therefore, oxygen and nutrients, to tissues and organs.

vascularIt also provides a means of transporting waste materials away from tissues and organs. Dr. Luiz Bertassoni. the lead author of the study explained:

Cells die without an adequate blood supply because blood supplies oxygen that’s necessary for cells to grow and perform a range of functions in the body. To illustrate the scale and complexity of the bio-engineering challenge we face, consider that every cell in the body is just a hair’s width from a supply of oxygenated blood. Replicating the complexity of these networks has been a stumbling block preventing tissue engineering from becoming a real world clinical application.

In order to solve this problem, the researchers used a bioprinter to create a framework of tiny interconnected fibers to serve as a mold. The structure was then covered with a “cell-rich protein-based material” and solidified using light. The fibers were removed to leave a network of tiny channels that formed into stable human blood-capillaries within just a week’s time.

stem_cells3According to the University of Sydney study, the technique demonstrated better cell survival, differentiation and proliferation compared to cells that received no nutrient supply. In addition, it provides the ability to create large, life-supporting three-dimensional, micro-vascular channels quickly and with the precision required for application to different individuals.

This is a major step forward for the bioprinting industry, according to Bertassoni:

While recreating little parts of tissues in the lab is something that we have already been able to do, the possibility of printing three-dimensional tissues with functional blood capillaries in the blink of an eye is a game changer.

bioprinter1In addition, Bertassoni claims that the ultimate aim of the research is for patients to be able to walk into a hospital and have a full organ printed with all the cells, proteins and blood vessels in the right place:

We are still far away from that, but our research is addressing exactly that. Our finding is an important new step towards achieving these goals. At the moment, we are pretty much printing ‘prototypes’ that, as we improve, will eventually be used to change the way we treat patients worldwide.

Bioprinting that uses a patient’s own DNA to generate custom-made organs and tissues offers a world of medical possibilities in which organ donors are no longer necessary, and the risk of rejection and incompatibility is negligible. Not only that, it will usher in a world where no injury is permanent and prosthetics are a thins of the past.

Sources: gizmag.com, sydney.edu.au

The Future is Here: 3-D Printed Eye Cells

printed_eyecells3In the past few years, medical researchers have been able to replicate real, living tissues samples using 3-D printing technology – ranging from replacement ears and printed cartilage to miniature kidneys and even liver cells. Well now, thanks to a team of researchers from the University of Cambridge, eye cells have been added to that list.

Using a standard ink-jet printer to form layers of two types of cells,  the research team managed to print two types of central nervous system cells from the retinas of adult rats – ganglion cells (which transmit information from the eye to the brain), and glial cells (which provide protection and support for neurons). The resulting cells were able to grow normally and remain healthy in culture.

printed_eyecells2Ink-jet printing has been used to deposit cells before, but this is the first time cells from an adult animal’s central nervous system have been printed. The research team published its research in the IOP Publishing’s open-access journal Biofabrication and plans to extend this study to print other cells of the retina and light-sensitive photoreceptors.

In the report, Keith Martin and Barbara Lorber – the co-authors of the paper who work at the John van Geest Centre for Brain Repair at the University of Cambridge – explained the experiment in detail:

Our study has shown, for the first time, that cells derived from the mature central nervous system, the eye, can be printed using a piezoelectric inkjet printer. Although our results are preliminary and much more work is still required, the aim is to develop this technology for use in retinal repair in the future.

printed_eyecellsThis is especially good news for people with impaired visual acuity, or those who fear losing their sight, as it could lead to new therapies for retinal disorders such as blindness and macular degeneration. Naturally, more tests are needed before human trials can begin. But the research and its conclusions are quite reassuring that eye cells can not only be produced synthetically, but will remain healthy after they are produced.

Clara Eaglen, a spokesperson for the Royal National Institute of Blind People (RNIB), had this to say about the breakthrough:

The key to this research, once the technology has moved on, will be how much useful vision is restored. Even a small bit of sight can make a real difference, for some people it could be the difference between leaving the house on their own or not. It could help boost people’s confidence and in turn their independence.

printed_eyecells1Combined with bionic eyes that are now approved for distribution in the US, and stem cell treatments that have restores sight in mice, this could be the beginning of the end of blindness. And with all the strides being made in bioprinting and biofabrication, it could also be another step on the long road to replacement organs and print-on-demand body parts.

Sources: news.cnet.com, singularityhub.com, cam.ca.uk, bbc.co.uk