Compare the effect of different chemical methods for preparation of acellular nerve scaffold and to provide an effective nerve scaffold for tissue engineering. Methods Fifteen male SD rats of 2 months old, weighing 200-250 g were selected; the bilateral sciatic nerves were harvested and divided into 3 groups according to preparation methods: group A (normal nerve), group B (Sondell method) and group C (optimal method by Triton X-200, SB-10 and SB-16). The morphology was compared by HE, immunohistochemistry and SEM after dispose; the degrees of decellularization, degrees of demyel ination and integrity of the nerve fiber tube were assessed by scoring system. Results HE staining: In group A, thecross section of nerve was roundness, the cell nuclei was dark blue and the myel in sheath was reticular structure. In group B, the axon and cell nuclei disappeared and the structure of endoneurium was destroyed. In group C, the axon and cell nuclei disappeared and the endoneurium become anomal istic round cavum. The immunohistochemistry staining of Laminin: In group A, the myel in sheath was surrounded by basement membrane with dark blue SC nuclei inside. In group B, the myel in sheath and SC nuclei disappeared and the structure of basement membrane destroyed. In group C, the myel in sheath and SC nuclei disappeared and basement membrane become anomal istic round cavum. The immunohistochemistry staining of S-100: In group A, the myel in sheath and SC were brown. In groups B and C, there were no apparent stained myel in sheath. SEM: In group A, the myel in sheath and axon were clear. In group B, the axon and myel in sheath disappeared and basement membrane became anomal istic. In group C, the basement membrane was more regular than that of group B. The degrees of acellularization and demyel ination of groups B and C were superior to that of group A (P lt; 0.05), and the degrees of demyel ination of group C were superior to that of group B (P lt; 0.05). The integrity of nerve fiber tube of group C was superior to that of group B (P lt; 0.05) and similar to that of group A (P gt; 0.05). The total score was the lowest in group C but the qual ity was the best. Conclusion The effect of decellularization of optimal method was similar to that of traditional Sondell method, but the effect of demyel ination and integrity of nerve fiber tube were better than that of traditional Sondell method. And this acellular nerve can be used as a new kind of nerve scaffold material.
Silicon carbide (SiC) film and silicon dioxide (SiO2) film were deposited on the surface of carbon/carbon composite (C/C) by low pressure chemical vapor deposition (LPCVD). The biocompatibility of the three carbon-based composites, e. g. C/C, C/C-SiC, C/C-SiO2 were investigated by cytotoxicity test, cell direct contact and cell adhesion experiments. Cytotoxicity, cell direct contact and cell adhesion showed that the three materials had no toxic effect on mouse fibroblasts (L929 cells). However, the particles dropped off from the three materials had a great impact on evaluation accuracy of the thiazolyl blue (MTT) test. More the particles were lost, more growth inhibition to L929 cells. The evaluation accuracy of MTT method can be kept with the filtered extract of materials. Furthermore, the results of surface particles shedding experiment showed that the amount of surface particles shed from C/C-SiO2 was the most, followed by C/C and C/C-SiC in 72 hours. Particles shedding curves showed there was a peak reached at eighth hour and then declined to the thirty-sixth hour. The filtrate analysis showed that there was no ion exchange between the three materials and simulated body fluid (SBF) solution. The results of this study on biocompatibility of carbon-based composites have certain guiding significance for their future application in clinical filed.