Intracellular Staphylococcus aureus Control by Virulent Bacteriophages within MAC-T Bovine Mammary Epithelial Cells

Area of Science:

• Microbiology
• Cell Biology
• Bacteriophage Therapy

Background:

• Bacteriophages (phages) are viruses that infect bacteria and are known for their ability to kill extracellular bacteria.
• Intracellular bacteria pose a significant challenge for conventional antimicrobial treatments, including phage therapy.
• Understanding phage-host interactions within host cells is crucial for developing novel therapeutic strategies.

Purpose of the Study:

• To investigate the ability of bacteriophages to penetrate host cells and eliminate intracellular bacteria.
• To determine the efficacy and kinetics of phage clearance of intracellular Staphylococcus aureus within bovine mammary epithelial cells.
• To assess the potential of phage therapy in targeting intracellular bacterial infections.

Main Methods:

• Bovine mammary epithelial cells were infected with Staphylococcus aureus.
• Cells were subsequently incubated with specific bacteriophages (e.g., vB_SauM_JS25).
• Time-dependent analysis of phage penetration and intracellular bacterial clearance was performed using microscopy and viable cell counts.

Main Results:

• Bacteriophages demonstrated the ability to penetrate bovine mammary epithelial cells.
• Phages effectively cleared intracellular Staphylococcus aureus in a time-dependent manner.
• One phage, vB_SauM_JS25, reached the cell nucleus within 3 hours, with an observed endocytotic efficiency of 12%.

Conclusions:

• Bacteriophages can effectively target and eliminate intracellular bacteria within host cells.
• The intracellular activity of phages suggests their potential as a therapeutic agent against persistent and recurrent bacterial infections.
• Phage therapy may offer a novel approach to overcome treatment failures caused by intracellular bacterial pathogens.