This could affect people disabled by osteoarthritis, which slowly destroys the tissue that cushions joints. Hundreds of thousands others damage cartilage through sports-related injuries and other accidents.
The new technique involves growing cartilage cells within a novel "designer" gel outside the body, then ultimately delivering the cell-seeded gel into a damaged joint. The idea is that the tissue will grow and integrate with the normal cartilage surrounding it while the gel slowly degrades, leaving behind a functioning tissue.
The researchers describe the first promising steps toward this goal in the issue of the Proceedings of the National Academy of Sciences published online the week of July 15-19. Although the engineered tissue has yet to be tested in animals, "it has mechanical and biochemical properties near to those of native cartilage," said Alan Grodzinsky, a professor with appointments in the Biological Engineering Division, the Department of Electrical Engineering and Computer Science and the Department of Mechanical Engineering.
"The implication is that the [new] gel provides a suitable environment for encapsulation of cartilage cells, with the goal of creating an implant that may be used to repair cartilage defects," said John Kisiday, first author of the paper and a graduate student in the Biological Engineering DIvision.
Kisiday and Grodzinsky's coauthors are former mechanical engineering graduate student Moonsoo Jin; Bodo Kurz; Han-Hwa Hung, a member of the research staff at MIT's Center for Biomedical Engineering (CBE); Carlos Semino, a CBE research scientist; and Shuguang Zhang, CBE associate director. Grodzinsky is director of the CBE.