An essential step toward printing living tissues

A new bioprinting method developed at the Harvard School of Engineering and Applied Sciences (SEAS) and the Wyss Institute for Biologically Inspired Engineering at Harvard University creates intricately patterned, three-dimensional tissue constructs with multiple types of cells and tiny blood vessels. The work represents a major step toward a longstanding goal of tissue engineers: creating human tissue constructs realistic enough to test drug safety and effectiveness. The method also represents an early but important step toward building fully functional replacements for injured or diseased tissue that can be designed from CAT scan data using computer-aided design (CAD), printed in 3D at the push of a button, and used by surgeons to repair or replace damaged tissue. "This is the foundational step toward creating 3D living tissue," said Jennifer A. Lewis , senior author of the study, who is the Hansjörg Wyss Professor of Biologically Inspired Engineering at Harvard SEAS and a Core Faculty Member of the Wyss Institute. Along with lead author David Kolesky, a graduate student in SEAS with a fellowship from the Wyss Institute, Lewis' team reported the results February 18 in the journal Advanced Materials . Tissue engineers have tried for years to produce lab-grown vascularized human tissues robust enough to serve as replacements for damaged human tissue. Others have printed human tissue before, but they have been limited to thin slices of tissue about a third as thick as a dime.