title: The repair of osteochondral defects using baculovirus-mediated gene transfer with de-differentiated chondrocytes in bioreactor culture.
abstract: Baculovirus has emerged as a promising gene delivery vector. Hereby de-differentiated rabbit chondrocytes were transduced ex vivo with a recombinant baculovirus expressing BMP-2 (Bac-CB), seeded to scaffolds and cultured statically for 1 day (Bac-w0 group) or in a rotating-shaft bioreactor (RSB) for 1 week (Bac-w1 group) or 3 weeks (Bac-w3 group). Mock-transduced constructs were cultured statically for 1 day to serve as the control (Mock-w0 group). We unraveled that Bac-CB transduction and increasing culture time in the RSB yielded more mature cartilaginous constructs in vitro. Eight weeks after implanting into the rabbit osteochondral defects, Mock-w0 constructs failed to repair the lesion while Bac-w0 constructs resulted in augmented, yet incomplete, repair. Bac-w1 constructs yielded neocartilage layers rich in glycosaminoglycans and collagen II, but the integration between the graft and host cartilages was not complete. In contrast, Bac-w3 constructs led to the regeneration of hyaline cartilages as characterized by cartilage-like appearance, improved integration, chondrocytes clustered in lacunae, smooth and homogeneous matrix rich in collagen II and glycosaminoglycans but deficient in collagen I. In conclusion, combining baculovirus-modified de-differentiated chondrocytes and RSB culture creates constructs that repair osteochondral defects, and in vitro culture time dictates the construct maturation and subsequent in vivo repair.
authors.affiliation: Department of Chemical Engineering, National Tsing Hua University, 101, Sec. 2 Kuang Fu Road, Hsinchu 300, Taiwan.
authors.forename: Huang-Chi
authors.initials: HC
authors.lastname: Chen
authors.forename: Yu-Han
authors.initials: YH
authors.lastname: Chang
authors.forename: Ching-Kuang
authors.initials: CK
authors.lastname: Chuang
authors.forename: Chin-Yu
authors.initials: CY
authors.lastname: Lin
authors.forename: Li-Yu
authors.initials: LY
authors.lastname: Sung
authors.forename: Yao-Horng
authors.initials: YH
authors.lastname: Wang
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Hu
mesh_terms: D000818:Animals; D016367:Baculoviridae / Q000378:metabolism*; D019149:Bioreactors; D001847:Bone Diseases / Q000235:genetics* / Q000628:therapy*; D002356:Cartilage / Q000378:metabolism; D054337:Cell Dedifferentiation; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology* / Q000378:metabolism; D005786:Gene Expression Regulation; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D009928:Organ Specificity; D019919:Prosthesis Implantation; D011817:Rabbits; D013997:Time Factors; D023822:Tissue Engineering; D014945:Wound Healing