Open AccessThe combination of silver-containing hydroxyapatite coating and vancomycin has a synergistic antibacterial effect on methicillin-resistant Staphylococcus aureus biofilm formation
Author(s) -
Akira Hashimoto,
Hiroshi Miyamoto,
Tomoki Kobatake,
Takema Nakashima,
Takeo Shobuike,
Masaya Ueno,
Takayuki Murakami,
Ichiro Noda,
Motoki Sonohata,
Masaaki Mawatari
Publication year - 2020
Publication title -
bone and joint research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.639
H-Index - 31
ISSN - 2046-3758
DOI - 10.1302/2046-3758.95.bjr-2019-0326.r1
Subject(s) - biofilm , staphylococcus aureus , in vivo , microbiology and biotechnology , vancomycin , colony forming unit , chemistry , methicillin resistant staphylococcus aureus , inoculation , bacteria , medicine , biology , pathology , genetics
Aims Biofilm formation is intrinsic to prosthetic joint infection (PJI). In the current study, we evaluated the effects of silver-containing hydroxyapatite (Ag-HA) coating and vancomycin (VCM) on methicillin-resistant Staphylococcus aureus (MRSA) biofilm formation.Methods Pure titanium discs (Ti discs), Ti discs coated with HA (HA discs), and 3% Ag-HA discs developed using a thermal spraying were inoculated with MRSA suspensions containing a mean in vitro 4.3 (SD 0.8) x 10 6 or 43.0 (SD 8.4) x 10 5 colony-forming units (CFUs). Immediately after MRSA inoculation, sterile phosphate-buffered saline or VCM (20 µg/ml) was added, and the discs were incubated for 24 hours at 37°C. Viable cell counting, 3D confocal laser scanning microscopy with Airyscan, and scanning electron microscopy were then performed. HA discs and Ag HA discs were implanted subcutaneously in vivo in the dorsum of rats, and MRSA suspensions containing a mean in vivo 7.2 (SD 0.4) x 10 6 or 72.0 (SD 4.2) x 10 5 CFUs were inoculated on the discs. VCM was injected subcutaneously daily every 12 hours followed by viable cell counting.Results Biofilms that formed on HA discs were thicker and larger than those on Ti discs, whereas those on Ag-HA discs were thinner and smaller than those on Ti discs. Viable bacterial counts in vivo revealed that Ag-HA combined with VCM was the most effective treatment.Conclusion Ag-HA with VCM has a potential synergistic effect in reducing MRSA biofilm formation and can thus be useful for preventing and treating PJI. Cite this article: Bone Joint Res. 2020;9(5):211–218.