Dual antibiotic PLGA microspheres for the treatment of traumatic osteomyelitis

Area of Science:

• Biomaterials Science
• Infectious Diseases
• Drug Delivery Systems

Background:

• Traumatic osteomyelitis (TO) presents significant treatment challenges, primarily due to bacterial biofilm formation and inadequate antibiotic penetration to the infection site.
• Current treatment strategies often struggle to achieve effective bacterial eradication, leading to chronic infections and prolonged patient suffering.

Purpose of the Study:

• To develop and evaluate poly(lactic-co-glycolic acid) (PLGA) microspheres co-loaded with moxifloxacin and rifampicin (M/R-P) for the localized treatment of traumatic osteomyelitis.
• To assess the safety, cytocompatibility, and in vivo antibacterial efficacy of the M/R-P microspheres against Staphylococcus aureus (MRSA) in a traumatic osteomyelitis model.

Main Methods:

• PLGA microspheres were formulated to co-load moxifloxacin and rifampicin.
• In vitro assessments included cytotoxicity assays (CCK-8, live/dead staining, SEM) and evaluation of osteogenic potential (ALP activity).
• In vivo efficacy was determined by quantifying bacterial burden (CFU/g) and assessing infection resolution via histopathology in a relevant animal model.

Main Results:

• In vitro studies confirmed that the M/R-P microspheres exhibited no cytotoxicity and did not inhibit osteogenic potential.
• In vivo, M/R-P microspheres significantly reduced MRSA bacterial burden compared to debridement-only controls (8 ± 3 × 10³ CFU/g vs. 3143 ± 727 × 10³ CFU/g; p < 0.0001).
• Histopathological analysis indicated near-complete resolution of infection in the M/R-P microsphere treatment group.

Conclusions:

• The developed M/R-P microspheres demonstrate excellent safety profiles, favorable cytocompatibility, and remarkable antibacterial efficacy for traumatic osteomyelitis.
• PLGA microspheres serve as a feasible and effective drug delivery carrier for localized antibiotic therapy in chronic osteomyelitis.
• This innovative approach offers a novel strategic direction for overcoming the clinical challenges associated with traumatic osteomyelitis treatment.