Intravital molecular imaging reveals that ROS-caspase-3-GSDME-induced cell punching enhances humoral immunotherapy targeting intracellular tumor antigens
Bolei Dai, Ren Zhang, Shuhong Qi, Lei Liu, Xian Zhang, Deqiang Deng, Jie Zhang, Yilun Xu, Fanxuan Liu, Zheng Liu, Qingming Luo, Zhihong Zhang
Abstract
Tumor antigens (TAs)-induced humoral immune responses or TAs-specific antibodies have great application prospects for tumor therapy. However, more than half of TAs are intracellular antigens (intra-Ags) that are hardly recognized by antibodies. It is worthy to develop immunotherapeutic strategies for targeting intra-Ags. Methods: We used the far-red fluorescent protein tfRFP as an intracellular antigen to immunize mice and generated a liver metastasis model by injecting tfRFP-expressing B16 melanoma cells (tfRFP-B16) via the spleen. Intravital molecular imaging and atomic force microscopy were performed to visualize the formation of tfRFP antigen-antibody complexes (also known as immune complexes) and punched holes in cell membranes.