Controlled release of growth factors on allograft bone in vitro.
Allografts are important alternatives to autografts for treating defects after major bone loss. Bone growth factors have both local autocrine and paracrine effects and regulate the growth, proliferation, and differentiation of osteoprogenitor cells. To study the effects of prolonged, continuous, local delivery of growth factors on bone growth, we developed a new microelectromechanical system (MEMS) drug delivery device. Bone marrow cells from mice were seeded on mouse allograft discs and cultured in osteogenic media with osteogenic protein 1 (OP-1) and/or basic fibroblast growth factor (FGF-2) delivered from MEMS devices for 6 weeks. We monitored bone formation by changes of bone volume using micro-CT scanning and release of osteocalcin using ELISA. The data suggest the MEMS devices delivered constant concentrations of OP-1 and FGF-2 to the media. Bone marrow cells grew on the allografts and increased bone volume. Addition of OP-1 increased bone formation whereas FGF-2 decreased bone formation. Local delivery of growth factors over a prolonged period modulated the differentiation of osteoprogenitor cells on allograft bone.
Huang
Zhinong
Z
Department of Orthopaedic Surgery, Stanford University Medical Center, Edwards Building R116, 300 Pasteur Drive, Stanford, CA 94305, USA. Zhinong@stanford.edu
Ryu
Wonhyoung
W
Ren
Peigen
P
Fasching
Rainer
R
Goodman
Stuart B
SB
D000818:Animals; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage*; D016025:Bone Transplantation; D002478:Cells, Cultured; D003470:Culture Media; D016222:Fibroblast Growth Factor 2 / Q000008:administration & dosage; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016212:Transforming Growth Factor beta / Q000008:administration & dosage*; D014184:Transplantation, Homologous
D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D003470:Culture Media; D016212:Transforming Growth Factor beta; D016222:Fibroblast Growth Factor 2