Cambridge, MA (PRWEB) July 16, 2013
Damaged organs could be repaired in the near future with devices enabled by a manufacturing technique used today for components in mobile phones and other consumer electronics. Researchers at Draper Laboratory and MIT demonstrated a prototype device using this approach under contract to the National Institutes of Health (NIH). The long term goal for the research is to develop implantable, fully functioning artificial tissues and organs.
In an early view article published online by Advanced Materials, Lisa E. Freed, the principal investigator for the project at Draper Laboratory and MIT, and Martin E. Kolewe, a post doctoral associate at MIT, adapted a semi-automated layer-by-layer assembly method commonly used to build integrated circuits in the electronics packaging industry to instead stack porous, flexible, biodegradable elastomer sheets to form three dimensional (3-D) scaffolds on which tissues can be grown. The breakthrough allows researchers to build controlled 3-D pore networks that guide cells to grow in precise patterns, as is seen in highly specialized tissues like heart and skeletal muscle.
Cells in a human heart rely on a variety of spatial and chemical cues to form the hierarchical organization that results in a complete and functional organ. “Function follows form, especially when we try to create artificial tissue,” Kolewe said, explaining that the researchers first identified key structural cues that could guide specific cell growth patterns, and then replicated these cues in their scaffolds to grow specific tissue architectures. The researchers were able to grow contractile heart tissue from rat heart cells using their 3-D scaffolds.
Before this work, researchers intent on growing human tissues lacked the ability to precisely control the 3-D pore structure of scaffolds in many types of polymers, instead relying on 2-dimensional templates, random 3D pore structures, or amorphous gelatin. While relatively simple organs like bladders can be grown using such methods, for more complex tissues like the heart or the brain a 3-D structure to guide specialized cell growth patterns is necessary. “Scaffolds that guide 3-D cellular arrangements can enable the fabrication of tissues large enough to be of clinical relevance, and now we have developed a new tool to help do this,” Freed said.
Freed explains that this work is driven by “the shortage of human tissue in medicine,” explaining that this technology could be implemented to facilitate the growth or regrowth of specific tissues in people with congenital defects or traumatic damage to their tissues or organs. The flexible scaffolds could be implanted at the site of the injury to guide cellular growth, afterwards dissolving harmlessly into the body. Biomedical researchers can also take advantage of these scaffolds for purposes including studying tissue development and identifying key cues that prompt a blob of heart cells to grow into a fully functional, beating heart muscle, for example.
The new design paradigm of controlling the network pore structure marks a huge improvement on the current methods used to grow human tissues, and will enable researchers to explore innovative new treatments and research possibilities.
“This novel fabrication technology highlights how the NIH’s investment in regenerative medicine may soon improve the lives of patients with damaged or diseased organs,” noted Martha Lundberg, a program director at the NIH’s National Heart, Lung, and Blood Institute (NHLBI), which supported this study. “This work could be a potentially significant advance in tissue engineering that will lead to new tissue-based therapies aimed at restoring organ function.”
The work was funded by a grant to MIT from the NHLBI of the NIH under award number R01HL107503. Its content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. Other authors of the Advanced Materials paper were Hyoungshin Park and Caprice Gray from Draper and Xiaofeng Ye and Robert Langer from MIT. The authors dedicated the paper to the memory of MIT police officer Sean Collier.
Draper Laboratory, which celebrates 80 years of service to the nation in 2013, is a not-for-profit, engineering research and development organization dedicated to solving critical national problems in national security, space systems, biomedical systems, and energy. Core capabilities include guidance, navigation and control; miniature low power systems; highly reliable complex systems; information and decision systems; autonomous systems; biomedical and chemical systems; and secure networks and communications.