AIM: To study the optical property and biocompatibility of a tissue engineering cornea. METHODS: The cross-linker of N- (3-Dimethylaminoropyl)-N'ethylcarbodiimide hydrochloride (EDC)/ N-Hydroxysuccinimide (NHS) wa...AIM: To study the optical property and biocompatibility of a tissue engineering cornea. METHODS: The cross-linker of N- (3-Dimethylaminoropyl)-N'ethylcarbodiimide hydrochloride (EDC)/ N-Hydroxysuccinimide (NHS) was mixed with Type I collagen at 10% (weight/volume). The final solution was molded to the shape of a corneal contact lens. The collagen concentrations of 10%, 12.5%, 15%, 17.5% and 20% artificial corneas were tested by UV/vis-spectroscopy for their transparency compared with normal rat cornea. 10-0 sutures were knotted on the edges of substitute to measure the corneal buttons's mechanical properties. Normal rat corneal tissue primary culture on the collagen scaffold was observed in 4 weeks. Histopathologic examinations were performed after 4 weeks of in vitro culturing. RESULTS: The collagen scaffold appearance was similar to that of soft contact lens. With the increase of collagen concentration, the transparency of artificial corneal buttons was diminished, but the toughness of the scaffold was enhanced. The scaffold transparency in the 10% concentration collagen group resembled normal rat cornea. To knot and embed the scaffold under the microscope, 20% concentration collagen group was more effective during implantation than lower concentrations of collagen group. In the first 3 weeks, corneal cell proliferation was highly active. The shapes of cells that grew on the substitute had no significant difference when compared with the cells before they were moved to the scaffold. However, on the fortieth day, most cells detached from the scaffold and died. Histopathologic examination of the primary culture scaffold revealed well grown corneal cells tightly attached to the scaffold in the former culturing. CONCLUSION: Collagen scaffold can be molded to the shape of soft contact corneal lens with NHS/EDC. The biological stability and biocompatibility of collagen from animal species may be used as material in preparing to engineer artificial corneal scaffold.展开更多
Collagen-based biomaterials are used widely as tissue engineering scaffolds because of their excellent bioactivity and their similarity to the natural ECM.The regeneration of healthy bone tissue requires simultaneous ...Collagen-based biomaterials are used widely as tissue engineering scaffolds because of their excellent bioactivity and their similarity to the natural ECM.The regeneration of healthy bone tissue requires simultaneous support for both osteoblasts and,where angiogenesis is intended,endothelial cells.Hence it is important to tailor carefully the biochemical and structural characteristics of the scaffold to suit the needs of each cell type.This work describes for the first time a systematic study to gain insight into the cell type-specific response of primary human osteoblast(hOBs)and human dermal microvascular endothelial cells(HDMECs)to insoluble collagen-based biomaterials.The behaviour was evaluated on both 2D films and 3D scaffolds,produced using freeze-drying.The collagen was cross-linked at various EDC/NHS concentrations and mono-cultured with hOBs and HDMECs to assess the effect of architectural features and scaffold stabilization on cell behaviour.It was observed that 3D scaffolds cross-linked at 30%of the standard conditions in literature offered an optimal combination of mechanical stiffness and cellular response for both cell types,although endothelial cells were more sensitive to the degree of cross-linking than hOBs.Architectural features have a time-dependent impact on the cell migration profile,with alignment being the most influential parameter overall.展开更多
基金Scientific and Technological Research Projects of Educational Committee of Liaoning Province of China(No.2008S243)
文摘AIM: To study the optical property and biocompatibility of a tissue engineering cornea. METHODS: The cross-linker of N- (3-Dimethylaminoropyl)-N'ethylcarbodiimide hydrochloride (EDC)/ N-Hydroxysuccinimide (NHS) was mixed with Type I collagen at 10% (weight/volume). The final solution was molded to the shape of a corneal contact lens. The collagen concentrations of 10%, 12.5%, 15%, 17.5% and 20% artificial corneas were tested by UV/vis-spectroscopy for their transparency compared with normal rat cornea. 10-0 sutures were knotted on the edges of substitute to measure the corneal buttons's mechanical properties. Normal rat corneal tissue primary culture on the collagen scaffold was observed in 4 weeks. Histopathologic examinations were performed after 4 weeks of in vitro culturing. RESULTS: The collagen scaffold appearance was similar to that of soft contact lens. With the increase of collagen concentration, the transparency of artificial corneal buttons was diminished, but the toughness of the scaffold was enhanced. The scaffold transparency in the 10% concentration collagen group resembled normal rat cornea. To knot and embed the scaffold under the microscope, 20% concentration collagen group was more effective during implantation than lower concentrations of collagen group. In the first 3 weeks, corneal cell proliferation was highly active. The shapes of cells that grew on the substitute had no significant difference when compared with the cells before they were moved to the scaffold. However, on the fortieth day, most cells detached from the scaffold and died. Histopathologic examination of the primary culture scaffold revealed well grown corneal cells tightly attached to the scaffold in the former culturing. CONCLUSION: Collagen scaffold can be molded to the shape of soft contact corneal lens with NHS/EDC. The biological stability and biocompatibility of collagen from animal species may be used as material in preparing to engineer artificial corneal scaffold.
基金supported by the Engineering and Physical Sciences Research Council(EPSRC)and Geistlich Pharma AG.R.E.C.and S.M.B.acknowledge funding from an EPSRC Professorial Fellowship(EP/N019938/1)which also supported the research undertaken by D.V.B.D.V.B.would like to thank the Cambridge Royce facilities grant EP/P024947/1 and Sir Henry Royce Institute-recurrent grant EP/R00661X/1.
文摘Collagen-based biomaterials are used widely as tissue engineering scaffolds because of their excellent bioactivity and their similarity to the natural ECM.The regeneration of healthy bone tissue requires simultaneous support for both osteoblasts and,where angiogenesis is intended,endothelial cells.Hence it is important to tailor carefully the biochemical and structural characteristics of the scaffold to suit the needs of each cell type.This work describes for the first time a systematic study to gain insight into the cell type-specific response of primary human osteoblast(hOBs)and human dermal microvascular endothelial cells(HDMECs)to insoluble collagen-based biomaterials.The behaviour was evaluated on both 2D films and 3D scaffolds,produced using freeze-drying.The collagen was cross-linked at various EDC/NHS concentrations and mono-cultured with hOBs and HDMECs to assess the effect of architectural features and scaffold stabilization on cell behaviour.It was observed that 3D scaffolds cross-linked at 30%of the standard conditions in literature offered an optimal combination of mechanical stiffness and cellular response for both cell types,although endothelial cells were more sensitive to the degree of cross-linking than hOBs.Architectural features have a time-dependent impact on the cell migration profile,with alignment being the most influential parameter overall.