Light-Independent M1 Macrophage Polarization by Photosensitizer-Loaded Protein Corona on Gold Nanorods

Abstract

Aim: To establish a light-independent functionality of gold nanorods (AuNRs) with a human serum (HS) protein corona loaded with photosensitizer Chlorin e6 (AuNR-HS-Ce6) in M1 polarization of macrophages. Methods: RT-qPCR and ELISA were used to determine gene and protein expression, respectively. Uptake of AuNR-HS-Ce6 was determined via flow cytometry, inductively coupled plasma mass spectrometry and fluorescence microscopy. Cell viability was determined using PrestoBlue^® cell viability assay. Results: An increase in M1 gene and protein expression was observed in AuNR-HS-Ce6-treated macrophages. Delivery of high Ce6 payload via AuNR-HS-Ce6 was the primary contributor toward M1 polarization. Finally, DLD-1 cells treated with conditioned media from AuNR-HS-Ce6-treated macrophages showed significantly reduced proliferation. Conclusion: Our study suggests an immunomodulatory potential of Ce6 in inducing light-independent M1 polarization outside of its role as a photosensitizer.

Keywords::

• Chlorin e6
• gold nanorods
• immunotherapy
• macrophages
• M1 polarization
• multimodal therapy
• protein corona

Supplementary data

To view the supplementary data that accompany this paper please visit the journal website at: www.tandfonline.com/doi/suppl/10.2217/nnm-2020-0249

Author contributions

The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript.

Financial & competing interests disclosure

The funding used to support the research of the manuscript was from the Ministry of Education (MOE) AcRF Tier 1 Grant (WBS R-397-000-295-114). JUJ Cheah would like to acknowledge the scholarship support from NUS Graduate School of Integrative Sciences and Engineering. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Additional information

Funding

The funding used to support the research of the manuscript was from the Ministry of Education (MOE) AcRF Tier 1 Grant (WBS R-397-000-295-114). JUJ Cheah would like to acknowledge the scholarship support from NUS Graduate School of Integrative Sciences and Engineering. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.