Poly-epsilon-caprolactone/gel hybrid scaffolds for cartilage tissue engineering.
The aim of this study was to determine the suitability of hybrid scaffolds composed of naturally derived biopolymer gels and macroporous poly-epsilon-caprolactone (PCL) scaffolds for neocartilage formation in vitro. Rabbit articular chondrocytes were seeded into PCL/HA (1 wt % hyaluronan), PCL/CS (0.5 wt % chitosan), PCL/F (1:3 fibrin sealant plus aprotinin), and PCL/COL1 (0.24% type I collagen) hybrids and cultured statically for up to 50 days. Growth characteristics were evaluated by histological analysis, scanning electron microscopy, and confocal laser scanning microscopy. Neocartilage was quantified using a dimethyl-methylene blue assay for sulfated glycosaminoglycans (sGAG) and an enzyme-linked immunosorbent assay for type II collagen (COL2), normalized to dsDNA content by fluorescent PicoGreen assay. Chondrocytes were homogenously distributed throughout the entire scaffold and exhibited a predominantly spheroidal shape 1 h after being seeded into scaffolds. Immunofluorescence depicted expanding proteoglycan deposition with time. The sGAG per dsDNA increased in all hybrids between days 25 and 50. PCL/HA scaffolds consistently promoted highest yields. In contrast, total sGAG and total COL2 decreased in all hybrids except PCL/CS, which favored increasing values and a significantly higher total COL2 at day 50. Overall, dsDNA content decreased significantly with time, and particularly between days 3 and 6. The PCL/HA hybrid displayed two proliferation peaks at days 3 and 25, and PCL/COL1 displayed one proliferation peak at day 12. The developed hybrids provided distinct short-term environments for implanted chondrocytes, with not all of them being explicitly beneficial (PCL/F, PCL/COL1). The PCL/HA and PCL/CS hybrids, however, promoted specific neocartilage formation and initial cell retention and are thus promising for cartilage tissue engineering.
Schagemann
J C
JC
Cartilage and Connective Tissue Research Laboratory, Department of Orthopedic Research, Mayo Clinic College of Medicine, Rochester, Minnesota.
Chung
H W
HW
Mrosek
E H
EH
Stone
J J
JJ
Fitzsimmons
J S
JS
O'Driscoll
S W
SW
Reinholz
G G
GG
D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D002356:Cartilage / Q000166:cytology / Q000502:physiology; D018929:Cell Culture Techniques / Q000295:instrumentation / Q000379:methods; D019902:Chondrocytes / Q000378:metabolism / Q000648:ultrastructure; D004247:DNA / Q000032:analysis; D005782:Gels / Q000737:chemistry*; D006025:Glycosaminoglycans / Q000737:chemistry / Q000378:metabolism; D008422:Materials Testing; D011091:Polyesters / Q000737:chemistry*; D011817:Rabbits; D023822:Tissue Engineering / Q000295:instrumentation* / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
D001672:Biocompatible Materials; D005782:Gels; D006025:Glycosaminoglycans; D011091:Polyesters; C016240:polycaprolactone; D004247:DNA