Fabrication of drug-loaded tissue engineering scaffold and its curative effect for chronic osteomyelitis in rabbits
10.3760/cma.j.issn.1001-8050.2015.03.006
- VernacularTitle:载药组织工程支架的构建及其治疗兔慢性骨髓炎的疗效
- Author:
Bingyan XIANG
;
Yuan GUO
- Publication Type:Journal Article
- Keywords:
Tissue engineering;
Hydroxyapatites;
Chitosan;
Stents;
Osteomyelitis
- From:
Chinese Journal of Trauma
2015;31(3):212-216
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the anti-infection and bone repair effects of composite scaffolds encapsulated with vancomycin and bone morphogenetic protein-2 (BMP-2).Methods Chitosan (CS) solution and nano-hydroxyapatite (n-HAP) mixed in a ratio of 1∶1 were made into solid materials by freeze drrying technology,and immerged into BMP-2/polylactic acid (PLA) and vancomycin/PLA microsphere solution to fabricate drug-loaded scaffolds.Efficiency of drug release was measured.After the induction of chronic infectious tibial bone defect,60 New Zealand white rabbits were assigned to isolate debridement group (Group Ⅰ),n-HAP/CS scaffold group (Group Ⅱ),n-HAP/CS + vancomycin/PLA group (Group Ⅲ) and n-HAP/CS + vancomycin/PLA + BMP-2/PLA group (Group Ⅳ) according to the random number table,with 15 rabbits per group.After 8 weeks of treatment,X-ray filming,Norden score,HE staining and narrow culture were performed to evaluate the anti-infection ability and bone repair ability in each group.Results Pore size of the n-HAP/CS scaffold constructed in this study ranged from 80 to 270 μm (mean,146.53 μm).Biomechanical test showed the elastic modulus of the scaffold material was (27.50 ± 1.58)MPa and the compressive strength was (0.75 ± 0.04)MPa.BMP-2/PLA and vancomycin/PLA microspheres into ball shape uniformly distributed on the scaffold pores.Drug-loaded scaffold showed relatively stable release of vancomycin and BMP-2 in a period of 18 days.With the extended time amount of the drug release gradually reduced.On the X-ray films 8 weeks after the treatment,sinus formation was visible in groups Ⅲ and Ⅳ,and emergence of periosteal reaction with focal low density shadow was demonstrated in groups Ⅰ and Ⅱ.Norden scores of groups Ⅰ,Ⅱ,Ⅲ and Ⅳ were (2.64 ±0.33) points,(2.63 ±0.36) points,(1.14 ±0.29) points and (0.89 ±0.42) points respectively,indicating group Ⅳ ranked the lowest compared with other three groups (P<0.05) and group Ⅲ showed significant difference in comparison with groups Ⅰ and Ⅱ (P <0.05).HE staining showed massive infiltration of inflammatory cells and destroyed bone trabeculas in groups Ⅰ and Ⅱ,trabecular bone arranged neatly in groups Ⅲ and Ⅳ,and thicker trabecular bone in group Ⅳ than in group Ⅲ.Marrow culture showed obvious pale yellow colony formation in groups Ⅰ and Ⅱ,but no colony formation in groups Ⅲ and Ⅳ.Conclusions Vancomycin/BMP-2-loaded tissue engineering scaffolds are constructed successfully.Drug-loaded n-HAP/CS composite scaffold is identified as an ideal implant material for treatment of chronic osteomyelitis in rabbits