Penicillin-streptomycin influences macrophage mechanical properties and microenvironment mechano-sensation

Area of Science:

• Cell Biology
• Immunology
• Biophysics

Background:

• Penicillin-streptomycin (pen-strep) is a common antibiotic cocktail in cell culture.
• Its effects on macrophage mechanical properties and immune function are not well understood.

Purpose of the Study:

• To investigate the impact of pen-strep on macrophage mechanics, extracellular matrix (ECM) sensing, and immune function.
• To assess the implications of these changes for mechanobiology research and clinical applications.

Main Methods:

• Macrophage stiffness and adhesion measurements.
• Cell spreading assays on various substrates.
• Gene expression analysis (YAP-1, TAZ, β1 integrin).
• Assessment of reactive oxygen species (ROS) and phagocytic capacity.

Main Results:

• Pen-strep treatment increased macrophage stiffness over time.
• Altered cell spreading on different ECM components, indicating context-dependent mechanosensing.
• Upregulation of YAP-1/TAZ and downregulation of β1 integrin, suggesting mechanotransduction pathway reprogramming.
• Increased intracellular ROS, suppressed M1 polarization, induced heterogeneous M2 responses, and impaired phagocytosis.

Conclusions:

• Pen-strep significantly modulates macrophage stiffness, ECM sensing, polarization, and phagocytic function.
• These findings raise concerns regarding the routine use of pen-strep in mechanobiology research and clinical settings.
• Further investigation is needed to understand the long-term consequences of pen-strep exposure on immune cells.