title: Nisin F-loaded brushite bone cement prevented the growth of Staphylococcus aureus in vivo.
abstract: OBJECTIVE
  To determine if nisin F-loaded self-setting brushite cement could control the growth of Staphylococcus aureus in vivo.
  
  
  RESULTS
  Brushite cement was prepared by mixing equimolar concentrations of β-tricalcium phosphate and monocalcium phosphate monohydrate. Nisin F was added at 5·0, 2·5 and 1·0% (w/w) and the cement moulded into cylinders. In vitro antibacterial activity was determined using a delayed agar diffusion assay. Release of nisin F from the cement was determined using BCA protein assays. Based on scanning electron microscopy and X-ray diffraction analysis, nisin F did not cause significant changes in cement structure or chemistry. Cement containing 5·0% (w/w) nisin F yielded the most promising in vitro results. Nisin F-loaded cement was implanted into a subcutaneous pocket on the back of mice and then infected with S. aureus Xen 36. Infection was monitored for 7 days, using an in vivo imaging system. Nisin F prevented S. aureus infection for 7 days and no viable cells were isolated from the implants.
  
  
  CONCLUSIONS
  Nisin F-loaded brushite cement successfully prevented in vivo growth of S. aureus.
  
  
  CONCLUSIONS
  Nisin F incorporated into bone cement may be used to control S. aureus infection in vivo.
authors.affiliation: Department of Microbiology, University of Stellenbosch, Stellenbosch, South Africa.
authors.forename: A D
authors.initials: AD
authors.lastname: van Staden
authors.forename: A M
authors.initials: AM
authors.lastname: Brand
authors.forename: L M T
authors.initials: LM
authors.lastname: Dicks
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001843:Bone Cements / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D051379:Mice; D008855:Microscopy, Electron, Scanning; D009561:Nisin / Q000031:analogs & derivatives* / Q000494:pharmacology; D013203:Staphylococcal Infections / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development*; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; D001843:Bone Cements; D002130:Calcium Phosphates; C568830:nisin F, Lactococcus lactis; D009561:Nisin; C494366:calcium phosphate, dibasic, dihydrate