Future of regenerative medicine: challenges and hurdles.

Tissue regeneration strategies such as tissue engineering, growth factor administration, and stem cell-based therapies have undergone significant development over the past two decades. Most notably, we are much closer to realizing the engineering of whole organs and tissue with complex architecture than we were 5 years ago. A major driving force has been the demand placed by the scientific community at large and the public to go beyond simple engineering of tissues and demonstrate functionality in engineered tissues and functional recovery upon transplantation. Some recent advances include de novo engineering of bone, engineering of fully functional bladder, and vascularization of skeletal muscle constructs. Notwithstanding, several challenges lie ahead in making regenerative medicine a viable science of the future, the key being the evolution of programs and policies that promote a close relationship among government agencies, private sector, and academia, more specifically between materials scientists, biologists, and clinicians.