{"title":"Alternating magnetic fields (AMF) and linezolid reduce Staphylococcus aureus biofilm in a large animal implant model","authors":"","doi":"10.1016/j.jinf.2024.106271","DOIUrl":null,"url":null,"abstract":"<div><h3>Objectives</h3><p>We aimed to evaluate the effectiveness of alternating magnetic fields (AMF) combined with antibiotics in reducing <em>Staphylococcus aureus</em> biofilm on metal implants in a large animal model, compared to antibiotics alone.</p></div><div><h3>Methods</h3><p>Metal plates were inoculated with a clinical MRSA strain and then implanted into thirty-three ewes divided into three groups: positive control, linezolid only, and a combination of linezolid and AMF. Animals had either titanium or cobalt-chrome plates and were sacrificed at 5 or 21 days post-implantation. Blood and tissue samples were collected at various time points post-AMF treatment.</p></div><div><h3>Results</h3><p><em>In vivo</em> efficacy studies demonstrated significant biofilm reduction on titanium and cobalt-chrome implants with AMF-linezolid combination treatment compared to controls. Significant bacterial reductions were also observed in surrounding tissues and bones. Cytokine analysis showed improved inflammatory responses with combination therapy, and histopathology confirmed reduced inflammation, necrosis, and bacterial presence, especially at 5 days post-implantation.</p></div><div><h3>Conclusions</h3><p>This study demonstrates that combining AMF with antibiotics significantly reduces biofilm-associated infections on metal implants in a large animal model. Numerical simulations confirmed targeted heating, and <em>in vivo</em> results showed substantial bacterial load reduction and reduced inflammatory response. These findings support the potential of AMF as a non-invasive treatment for prosthetic joint infections.</p></div>","PeriodicalId":50180,"journal":{"name":"Journal of Infection","volume":null,"pages":null},"PeriodicalIF":14.3000,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0163445324002056/pdfft?md5=7b1b73004289824ab254d6287709619c&pid=1-s2.0-S0163445324002056-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Infection","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0163445324002056","RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"INFECTIOUS DISEASES","Score":null,"Total":0}
Alternating magnetic fields (AMF) and linezolid reduce Staphylococcus aureus biofilm in a large animal implant model
Objectives
We aimed to evaluate the effectiveness of alternating magnetic fields (AMF) combined with antibiotics in reducing Staphylococcus aureus biofilm on metal implants in a large animal model, compared to antibiotics alone.
Methods
Metal plates were inoculated with a clinical MRSA strain and then implanted into thirty-three ewes divided into three groups: positive control, linezolid only, and a combination of linezolid and AMF. Animals had either titanium or cobalt-chrome plates and were sacrificed at 5 or 21 days post-implantation. Blood and tissue samples were collected at various time points post-AMF treatment.
Results
In vivo efficacy studies demonstrated significant biofilm reduction on titanium and cobalt-chrome implants with AMF-linezolid combination treatment compared to controls. Significant bacterial reductions were also observed in surrounding tissues and bones. Cytokine analysis showed improved inflammatory responses with combination therapy, and histopathology confirmed reduced inflammation, necrosis, and bacterial presence, especially at 5 days post-implantation.
Conclusions
This study demonstrates that combining AMF with antibiotics significantly reduces biofilm-associated infections on metal implants in a large animal model. Numerical simulations confirmed targeted heating, and in vivo results showed substantial bacterial load reduction and reduced inflammatory response. These findings support the potential of AMF as a non-invasive treatment for prosthetic joint infections.
期刊介绍:
The Journal of Infection publishes original papers on all aspects of infection - clinical, microbiological and epidemiological. The Journal seeks to bring together knowledge from all specialties involved in infection research and clinical practice, and present the best work in the ever-changing field of infection.
Each issue brings you Editorials that describe current or controversial topics of interest, high quality Reviews to keep you in touch with the latest developments in specific fields of interest, an Epidemiology section reporting studies in the hospital and the general community, and a lively correspondence section.