Involvement of Nanotechnology in Cancer Immunotherapy

The Liquid metals (LM) are a novel family of materials possessing distinct physicochemical characteristics, including pure gallium (Ga) and alloys based on Ga. Using functional LM nanoparticles to convert light energy into heat energy and destroy malignant cells is one of the most well-known uses of LMs in photothermal therapy. Because of its excellent specificity, repeatability, and few side effects, LM-based phototherapy is superior to conventional cancer therapy.

In a recent groundbreaking discovery, scientists from the Japan Advanced Institute of Science and Technology (JAIST) synthesized multifunctional Ga-based nanoparticles that combine immunotherapy and phototherapy for cancer treatment.

The eutectic gallium-indium (EGaIn) LM alloy and the immunological modulator imiquimod (IMIQ) are both included in the synthesized new LM nanoparticle (PEG-IMIQ-LM), which is encased in the biocompatible surfactant DSPE-PEG2000-NH2.

For cancer theranostics, the researchers have created a versatile LM immunological nanostimulator. To address this, researchers have combined the fluorescent LM nanoparticle with one of the most promising immune checkpoint inhibitors, anti-programmed death ligand-1 antibody (Anti-PD-L1). Anti-PD-L1‒PEG–ICG–IMIQ–LM, the modified particle, was effectively disseminated and exhibited notable fluorescence. The tumor surface temperature rose linearly with increasing time after irradiation, indicating the nanoparticle's anticancer action.

By adding Anti-PD-L1 to the nanoparticle, the LM particle was able to bind to the cancer cells' PD-L1, designating them for phagocytosis by DC and macrophages. Anti-PD-L1–PEG–IMIQ–LM particles generated by lasers demonstrated the greatest and most thorough elimination of malignancy, as well as the quickest mending and recuperation.

Furthermore, animals treated with laser-induced Anti-PD-L1–PEG–IMIQ–LM particles showed longer longevity and sustained antitumor efficacy when the tumor returned.