TRAIL-functionalized gold nanoparticles selectively trigger apoptosis in polarized macrophages

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Cancer Biology

Background:

• Tumor-associated macrophages (TAMs), similar to M2 macrophages, promote tumor progression and are linked to poor prognosis in non-small cell lung cancer (NSCLC).
• Targeting TAMs is a promising strategy for cancer therapy.
• Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in cancer cells but not normal cells.

Purpose of the Study:

• To investigate nanogold-TRAIL complexes as a potential therapeutic agent against M2 macrophages.
• To evaluate the efficacy and selectivity of nanogold-TRAIL complexes in targeting M2 macrophages.

Main Methods:

• Conjugation of TRAIL protein to nanogold cores of varying sizes (3, 13, 30 nm) to create multivalent nanogold-TRAIL complexes.
• Assessment of nanogold-TRAIL complex cytotoxicity on M2-polarized macrophages, M1 macrophages, and normal cells.
• Evaluation of the effect of nanoparticle size and surface properties on TRAIL efficacy.

Main Results:

• Nanogold-TRAIL complexes significantly increased TRAIL's cytotoxicity against M2 macrophages (30-fold increase in IC50) by altering O-glycosylation levels.
• The enhanced cytotoxicity was dependent on the size and surface characteristics of the nanoparticles.
• Nanogold-TRAIL complexes demonstrated selectivity, remaining non-toxic to M1 macrophages and normal cells.

Conclusions:

• Nanogold-TRAIL complexes represent a novel and effective strategy for enhancing TRAIL-based cancer therapy.
• This approach offers a promising method for targeting immunosuppressive M2 macrophages in NSCLC.
• The multivalent nature of the nanogold-TRAIL complexes is key to their enhanced therapeutic efficacy.