title: Delivering bioactive molecules as instructive cues to engineered tissues.
abstract: BACKGROUND
  Growth factors and other bioactive molecules play a crucial role in the creation of functional engineered tissues from dissociated cells.
  
  
  METHODS
  This review discusses the delivery of bioactive molecules - particularly growth factors - to affect cellular function in the context of tissue engineering. We discuss the primary biological themes that are addressed by delivering bioactives, the types of molecules that are to be delivered, the major materials used in producing scaffolds and/or drug delivery systems, and the principal drug delivery strategies.
  
  
  CONCLUSIONS
  Drug delivery systems have allowed the sustained release of bioactive molecules to engineered tissues, with marked effects on tissue function. Sophisticated drug delivery techniques will allow precise recapitulation of developmental milestones by providing temporally distinct patterns of release of multiple bioactives. High-resolution patterning techniques will allow tissue constructs to be designed with precisely defined areas where bioactives can act. New biological discoveries, just as the development of small molecules with potent effects on cell differentiation, will likely have a marked impact on the field.
authors.affiliation: Children's Hospital Boston, Harvard Medical School, Division of Critical Care Medicine, Department of Anesthesiology, Laboratory for Biomaterials and Drug Delivery, 300 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: Doris
authors.initials: D
authors.lastname: Gabriel
authors.forename: Tal
authors.initials: T
authors.lastname: Dvir
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Kohane
mesh_terms: D000893:Anti-Inflammatory Agents / Q000008:administration & dosage; D002470:Cell Survival; D003692:Delayed-Action Preparations / Q000008:administration & dosage; D016503:Drug Delivery Systems / Q000379:methods*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000008:administration & dosage*; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry; D055672:Static Electricity; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry
chemical_list: D000893:Anti-Inflammatory Agents; D003692:Delayed-Action Preparations; D036341:Intercellular Signaling Peptides and Proteins; D011108:Polymers