In vitro and in vivo osteogenic activity of the novel vancomycin-loaded bone-like hydroxyapatite/poly(amino acid) scaffold

Abstract

Background

Antibiotic-loaded carriers were developed because of their ability to fill cavities and deliver antibiotics locally following implantation. However, the most commonly used antibiotic carrier, polymethyl methacrylate, has many shortcomings, such as heat production, non-bioresorbable and lack of bone regeneration or conduction. Bone-like hydroxyapatite/poly(amino acid) scaffolds have been shown to have controllable biodegradability, nontoxicity, some osteogenic and osteoconductive properties, which has great potential as a carrier for local delivery of antibiotics. Vancomycin-loaded bone-like hydroxyapatite/poly(amino acid) was successfully fabricated by a homogeneous method using a diffusion control system. In this study, bone regeneration using this scaffold was observed both in vitro and in vivo.

Methods

In vitro tests, MG₆₃ cells were incubated with the vancomycin-loaded scaffold to observe its effects on the activation of osteoblasts. In vivo tests, the scaffolds were implanted into rabbit models of chronic osteomyelitis, including regular and methicillin-resistant Staphylococcus aureus. The effects were evaluated by gross observation, X-ray and histological observation.

Results

After incubating with the scaffold, MG₆₃ cells exhibited good proliferative activity, and increased calcium and alkaline phosphatase synthesis compared with blank control group. In vivo tests, the experimental group showed increased bone growth in infectious bone defects compared with the control groups, regardless of the type of Staphylococcus aureus.

Conclusion

Vancomycin-loaded bone-like hydroxyapatite/poly(amino acid) scaffold has good potential for the repair of infectious bone defects because of its ability to deliver antibiotics and promote bone regeneration.