Researchers at Wake Forest University in North Carolina have successfully created fully functioning urethras out of cells grown in a lab—a feat that bodes well for the future of regenerative medicine. The scientists took tissue from five boys plagued with urethral defects, coaxed that tissue to grow on "tubularised polyglycolic acid scaffolds"—in other words, they turned the tissue into tubes—and successfully inserted the tubes into the boys. “Tubularised urethras can be engineered and remain functional in a clinical setting for up to six years,” said the researchers. “These engineered urethras can be used in patients who need complex urethral reconstruction." An account of their work was published Tuesday in The Lancet.