Advances in tissue engineering

The clinical goals of tissue engineering are to restore, repair, or replace damaged or lost tissues in the body. Significant progress has been made in recent years, which includes the use of cells or polymer scaffolds as well as combinations of cells and polymers for engineering three-dimensional tissue constructs. However, major challenges still need to be addressed in order for these studies to progress into their clinical applications. The challenges include (1) developing functional polymers, (2) exploring more sources of human cells, and (3) finding ways to keep the engineered construct viable in vitro and in vivo. In addition to clinical applications, tissue engineering can provide new tools for studying cell and developmental biology by providing approaches for cell and tissue growth in three-dimensional environments. In this review we describe recent attempts in addressing some of the challenges of tissue engineering and discuss how such approaches may provide new insights into regulation of cell growth and differentiation. (C) 2004, Elsevier Inc.