Local delivery of a collagen-binding FGF-1 chimera to smooth muscle cells in collagen scaffolds for vascular tissue engineering.
We investigated the delivery of R136K-CBD (a collagen-binding mutant chimera of fibroblast growth factor-1) with a type I collagen scaffold as the delivery vehicle to smooth muscle cells (SMCs) for vascular tissue engineering. The binding affinity of R136K-CBD to 3-D collagen scaffolds was investigated both in the presence and absence of cells and/or salts. 2-D and 3-D visualization of delivery of R136K-CBD into SMCs were accomplished by combined fluorescent and reflection confocal microscopy. The mitogenic effect of collagen-immobilized R136K-CBD on SMCs in 3-D collagen was studied by Cyquant assay at different time intervals. In the group devoid of salt and cells, no detectable release of R136K-CBD into overlying culture media was found, compared with burst-and-continuous release of R136K and FGF-1 over a 14-day period in all other groups. The release rate of R136K-CBD was 1.7 and 1.6-fold less than R-136K and FGF-1 when media was supplemented with 2m salt (P<0.0001), and 2.6 and 2.5-fold less in cell-populated collagen hydrogels (P<0.0001), respectively. R136K-CBD showed essentially uniform binding to collagen and its distribution was dependent on that of the collagen scaffold. Internalization of R136K-CBD into SMCs was documented by confocal microscopy. 3-D local delivery of collagen-immobilized R136K-CBD increased the proliferation of SMCs in the collagen matrix to significantly greater levels and for a significantly greater duration than R136K or FGF-1, with 2.0 and 2.1-fold more mitogenicity than R136K and FGF-1 respectively (P<0.0001) at day 7. The results suggest that our collagen-binding fusion protein is an effective strategy for growth factor delivery for vascular tissue engineering.
Department of Surgery, Loyola University Medical Center, Maywood, IL 60153, USA.
Yonggang
Y
Pang
Xiaoli
X
Wang
Areck A
AA
Ucuzian
Eric M
EM
Brey
Wilson H
WH
Burgess
Kathryn J
KJ
Jones
Thomas D
TD
Alexander
Howard P
HP
Greisler
D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D040761:Biomimetic Materials / Q000737:chemistry; D001808:Blood Vessels / Q000254:growth & development; D018929:Cell Culture Techniques / Q000379:methods; D002478:Cells, Cultured; D003094:Collagen / Q000737:chemistry*; D003460:Crystallization / Q000379:methods; D004285:Dogs; D004337:Drug Carriers / Q000737:chemistry*; D016220:Fibroblast Growth Factor 1 / Q000008:administration & dosage* / Q000737:chemistry; D008422:Materials Testing; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D010316:Particle Size; D013499:Surface Properties; D023822:Tissue Engineering / Q000379:methods
D001672:Biocompatible Materials; D004337:Drug Carriers; D016220:Fibroblast Growth Factor 1; D003094:Collagen