海藻膠+幹細胞3d列印 治療眼角膜受損 (失明)

3D-printed corneas could save millions' vision JULY 17, 2018 BY NANCY CROTTIBritish scientists have 3D printed the first human corneas, yielding a potential fix to the worldwide shortage of corneas for implantation. The Newcastle University researchers created a bio-ink using stem cells from a healthy donor cornea mixed with alginate and collagen. They used a simple, low-cost 3D bio-printer to extrude the bio-ink in concentric circles to form the shape of a human cornea. It took less than 10 minutes to print. The proof-of-concept research was published in May in Experimental Eye Research. "Many teams across the world have been chasing the ideal bio-ink to make this process feasible," said lead researcher Che Connon, a professor of tissue engineering in a prepared statement. "Our unique gel – a combination of alginate and collagen – keeps the stem cells alive whilst producing a material which is stiff enough to hold its shape but soft enough to be squeezed out the nozzle of a 3D printer. "The researchers previously kept cells alive for weeks at room temperature within a similar hydrogel. Their ready-to-use bio-ink containing stem cells, will allow users to start printing tissues without having to worry about growing the cells separately, Connon added. The scientists, including first author Abigail Isaacson from the university's Institute of Genetic Medicine, also demonstrated that they could build a cornea to match a patient's unique specifications. The dimensions of the printed tissue were originally taken from an actual cornea. By scanning a patient's eye, they could use the data to rapidly print a cornea which matched the size and shape.Several years of testing must occur before the 3D printed corneas may be used for transplant, according to Connon."However, what we have shown is that it is feasible to print corneas using coordinates taken from a patient eye and that this approach has potential to combat the worldwide shortage," he said. As the outermost layer of the human eye, the cornea has an important role in focusing vision. About 10 million people worldwide need surgery to prevent corneal blindness due to diseases such as trachoma, an infectious disease. Another nearly 5 million people suffer total blindness due to corneal scarring caused by burns, lacerations, abrasion or disease. Reducing the need for donor corneas would help some people living with vision loss to regain their sight, according to Neil Ebenezer, MD, director of research, policy and innovation at Fight for Sight, UK charity that funds research into the prevention and treatment of blindness and eye disease."This research highlights the significant progress that has been made in this area and this study is important in bringing us one step closer to reducing the need for donor corneas, which would positively impact some patients living with sight loss," Ebenezer said in the statement.