Radioimmunotherapy combating biofilm-associated infection .

BACKGROUND

Addressing prosthetic joint infections poses a significant challenge within orthopedic surgery, marked by elevated morbidity and mortality rates. The presence of biofilms and infections attributed to () further complicates the scenario.

OBJECTIVE

To investigate the potential of radioimmunotherapy as an innovative intervention to tackle biofilm-associated infections.

METHODS

Our methodology involved employing specific monoclonal antibodies 4497-IgG1, designed for targeting wall teichoic acids found on and its biofilm. These antibodies were linked with radionuclides actinium-225 (Ac) and lutetium-177 (Lu) using DOTA as a chelator. Following this, we evaluated the susceptibility of and its biofilm to radioimmunotherapy , assessing bacterial viability and metabolic activity via colony-forming unit enumeration and xylenol tetrazolium assays.

RESULTS

Both [Ac]4497-IgG1 and [Lu]4497-IgG1 exhibited a noteworthy dose-dependent reduction in in planktonic cultures and biofilms over a 96-h exposure period, compared to non-specific antibody control groups. Specifically, doses of 7.4 kBq and 7.4 MBq of [Ac]4497-IgG1 and [Lu]4497-IgG1 resulted in a four-log reduction in planktonic bacterial counts. Within biofilms, 14.8 kBq of [Ac]4497-IgG1 and 14.8 Mbq [Lu]4497-IgG1 led to reductions of two and four logs, respectively.

CONCLUSION

Our findings underscore the effectiveness of [Ac]4497-IgG1 and [Lu]4497-IgG1 antibodies in exerting dose-dependent bactericidal effects against planktonic S. and biofilms . This suggests that radioimmunotherapy might serve as a promising targeted treatment approach for combating S. and its biofilm.