CaCO₃-Encapsulated Au Nanoparticles Modulate Macrophages toward M1-like Phenotype

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Immunology

Background:

• Macrophage plasticity allows polarization into pro-inflammatory (M1) or anti-inflammatory (M2) phenotypes.
• Reprogramming M2 macrophages to M1 is a promising strategy for cancer therapy.
• The immunomodulatory effects of gold nanoparticles (AuNPs) remain incompletely understood.

Purpose of the Study:

• To investigate the immunomodulatory effects of AuNPs and CaCO3-encapsulated AuNPs (Au@CaCO3 NPs) on macrophage polarization.
• To explore the potential of Au@CaCO3 NPs for reprogramming macrophages towards an M1 phenotype for cancer treatment.

Main Methods:

• Synthesis of AuNPs and Au@CaCO3 NPs.
• Co-incubation of synthesized nanoparticles with macrophage cells.
• Assessment of macrophage morphology, M1/M2 biomarker expression, and cytokine secretion.

Main Results:

• AuNPs alone induced an elongated cell morphology and promoted M2 polarization, evidenced by increased M2 biomarkers and cytokines.
• Au@CaCO3 NPs induced a round cellular morphology and promoted M1 polarization, indicated by M1 biomarker secretion and inflammatory cytokines.
• The CaCO3 encapsulation strategy effectively modulated macrophage polarization towards the M1 phenotype.

Conclusions:

• CaCO3 encapsulation of AuNPs provides an effective method for inducing M1 macrophage polarization.
• This strategy offers a novel approach for activating inflammation in macrophages, with potential applications in cancer therapy.
• Further research into nanoparticle-based immunomodulation could advance cancer treatment modalities.