Research of the anti-infective and osteogenic effects of the infection-prevention tissue engineered bones on femoral large bone defects in goats / 中华骨科杂志

ABSTRACT

Objective To establish the anti-infective tissue engineered bones (TEBs) and evaluate the anti-infective and osteogenic effects of the infection-prevention TEBs on femoral large bone defects in goats.Methods Based on the controlledrelease antibiotic system fibrin gel-coated vancomycin alginate beads (FG-Vanco-AB),the infection-prevention TEBs were established and evaluated.They were transplanted into the critical-size defects in the right femurs of goats.TEBs without the controlled-release antibiotic system were used as controls and transplanted into the left femoral defects.The breakpoint sensitivity of vancomycin (5 mg/mL) for S.aureus was used as a standard concentration.Postoperatively,the vancomycin concentrations in the lesion site,in the adjacent site and in the circulation,as well as the anti-infective effects of the infection-prevention TEBs were evaluated by High-performance liquid chromatography (HPLC).Bone hcaling was assessed by histology,CT and ECT.The results were used to evaluate the osteogenic effect of the infection-prevention TEBs.Results Results from ESM,CLSM and in vivo tracing showed that the in vitro and in vivo survival conditions of seeded cells were analogous to those of TEBs.The effective concentration (over the bactericidal concentration) of vancomycin in bilateral defects and in blood lasted for 28 days,2 days and 7 days,respectively.The concentration of vancomycin in the femur decreased gradually from the grafted site to both ends.At 28 and 56 days postoperatively,the ECT results showed no significant difference between the right and left femurs.CT and histology demonstrated that at 14,28 and 112 days after surgery,bone defects in the bilateral femurs were repaired synchronously,and were completely covered by new bone tissue after 112 days.Conclusion The anti-infective TEBs were successfully established.FG-Vanco -AB in the transplanted sites provided the local bone tissues with anti-infective capability whilst not interfered the process of bone reconstnction and wound healing.