Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the ...Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimization of the macroscopic holes silk^(+) tNGC a展开更多
With the development of biomaterials,more attention is paid to the adhesion characteristics between cells and materials.It is necessary to study the adhesive force with a suitable method.Silk fibroin(SF)is widely inve...With the development of biomaterials,more attention is paid to the adhesion characteristics between cells and materials.It is necessary to study the adhesive force with a suitable method.Silk fibroin(SF)is widely investigated in biomedical application due to its novel biocompatibility and mechanical properties.In this article,the micropipette aspiration method and measurement pattern of uniform cells in round shape(UCR)was used to study the initial adhesive force of three types of cells on pure silk fibroin films(SFFs).We also compared the adhesive forces of modified SFFs with that of pure SFFs.The results of adhesive force in the initial adhesive stage were in concordance with the results of MTT assay andmicroscope observation,which were confirmed by the above three cell lines and four kinds of SFFs.The results indicated UCR was an efficient and quantitative measurement pattern in initial adhesion stage.This article also provides a useful method in identifying initial cell-materials interactions.展开更多
基金supported by the Lorenz B?hler Fonds,#2/19 (obtained by the Neuroregeneration Group,Ludwig Boltzmann Institute for Traumatology)the City of Vienna project ImmunTissue,MA23#30-11 (obtained by the Department Life Science Engineering,University of Applied Sciences Technikum Wien)。
文摘Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimization of the macroscopic holes silk^(+) tNGC a
基金This work was supported by the National Natural Science Foundation of China(NSFC,no.51502192,11502158,31501212 and 51503140)Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(STIP,no.2016142)+4 种基金National Basic Research Program of China(973 project,2005CB623906)Natural Science Foundation for Young Scientists of Shanxi Province(no.2014021039-6 and 201601D021127)the Qualified Personnel Foundation of Taiyuan University of Technology(QPFT,no.tyut-rc201270a)the Youth Foundation of Taiyuan University of Technology(no.1205-04020102,2013Z020 and 2014TD066)the Technical Services Project of Taiyuan University of Technology(no.143230043-J).
文摘With the development of biomaterials,more attention is paid to the adhesion characteristics between cells and materials.It is necessary to study the adhesive force with a suitable method.Silk fibroin(SF)is widely investigated in biomedical application due to its novel biocompatibility and mechanical properties.In this article,the micropipette aspiration method and measurement pattern of uniform cells in round shape(UCR)was used to study the initial adhesive force of three types of cells on pure silk fibroin films(SFFs).We also compared the adhesive forces of modified SFFs with that of pure SFFs.The results of adhesive force in the initial adhesive stage were in concordance with the results of MTT assay andmicroscope observation,which were confirmed by the above three cell lines and four kinds of SFFs.The results indicated UCR was an efficient and quantitative measurement pattern in initial adhesion stage.This article also provides a useful method in identifying initial cell-materials interactions.