Biodegradable pH-responsive amorphous calcium carbonate nanoparticles as immunoadjuvants for multimodal imaging and enhanced photoimmunotherapy. Issue 36 (19th August 2020) - Wang, Meng
Abstract : Development of bioresponsive theranostic nanoparticles to enhance cancer diagnostics and control cancer metastasis. Abstract : Development of bioresponsive theranostic nanoparticles to enhance cancer diagnostics and control cancer metastasis is highly desirable. In this study, we developed such a bioresponsive theranostic nanoparticle for synergistic photoimmunotherapy. In particular, these nanoparticles were constructed by embedding indocyanine green (ICG) into Mn 2+ -doped amorphous calcium carbonate (ACC(Mn)) nanoparticles, followed by loading of the Toll-like-receptor-7 agonist imiquimod (IMQ). The IMQ@ACC(Mn)–ICG/PEG nanoparticles respond to the acidic pH of the tumor microenvironment (TME) and co-deliver ICG and IMQ into the tumor. Selective phototherapy was achieved upon activation using a near-infrared laser. In the presence of IMQ and arising from phototherapeutically treated tumor cells, tumor-associated antigens give rise to a strong antitumor immune response. Reversal of the immunosuppressive TME via H + scavenging of the tumor through ACC nanoparticles effectively inhibits tumor metastases. Moreover, the combination of ICG and Mn 2+ also serves as an advanced contrast agent for cancer multimode imaging. Overall, these bioresponsive nanoparticles provide a promising approach for cancer theranostics with promising potential for future clinical translation.