Photodynamic-therapy Activates Immune Response by disrupting Immunity Homeostasis of Tumor Cells, which Generates Vaccine for Cancer Therapy

Received: 2015.06.01; Accepted: 2015.10.21; Published: 2016.01.01 Photodynamic therapy (PDT), a regulatory approved cancer treatment, is reported to be capable of causing immunogenic apoptosis. The current data reveal PDT can cause the dysregulation of “eat me ” and “don’t eat me ” signal by generating reactive oxygen species (ROS)-mediated en-doplasmic reticulum (ER) stress. This dysregulation probably contribute to the increased uptake of PDT-killed Lewis lung carcinoma (LLC) cells by homologous dendritic cells (DCs), accompanied by phenotypic maturation (CD80high, CD86high, and CD40high) and functional stimulation (NOhigh, IL-10absent) of dendritic cells as well as subsequent T-cell responses. Morevover, C57BL/6 mice vaccinated with dendritic cells (DCs) pulsed with PDT-treated LLCs (PDT-DCs) or PDT-treated LLCs alone (PDT-LLCs) exhibited potent immunity against LLC tumors. In the current study, the PDT-induced immune response was characterized as a process related with the dysregulation of “eat me ” signal and “don’t eat me ” signal, revealing the possibility for developing PDT into an antitumor vaccination strategy for personalized cancer immunotherapy