Inducing bacterial calcification for systematic treatment and immunomodulation against methicillin-resistant...

Area of Science:

• Immunology
• Microbiology
• Biotechnology

Background:

• Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant global health threat due to widespread antibiotic resistance.
• Developing novel therapeutic strategies against MRSA is crucial for combating refractory bacterial infections.

Purpose of the Study:

• To develop and evaluate an antibody-polysialic acid (PSA) conjugate for targeting and eradicating MRSA.
• To investigate the mechanism of MRSA elimination induced by the conjugate, including bacterial calcification and immune modulation.

Main Methods:

• Conjugation of antigen-binding fragments of monoclonal antibodies against S. aureus wall-teichoic acid with PSA.
• In vitro and in vivo studies in mice to assess the efficacy and safety of the antibody-PSA conjugate.
• Analysis of bacterial calcification, immune cell activation (macrophages, monocytes), and expression of inflammatory markers (calprotectin, S100A8/S100A9).

Main Results:

• The antibody-PSA conjugate effectively targeted MRSA and induced bacterial calcification, hindering essential metabolic pathways.
• Bacterial calcification led to increased expression of calprotectin and S100A8/S100A9 in macrophages and monocytes.
• Systemic administration of the conjugate demonstrated high efficacy and safety in treating chronic MRSA lung infections and osteomyelitis in mice.

Conclusions:

• The antibody-PSA conjugate represents a promising therapeutic strategy for treating MRSA infections by combining direct bacterial targeting with immunomodulation.
• This approach offers a potential solution for drug-resistant bacterial infections and related chronic conditions.