fig4

Figure 4. Schematic illustration of how the engineered dendritic cell-derived exosome EmDEX@GA modulates the lymph node immune microenvironment. (A) Dendritic cells (DCs) were genetically engineered to overexpress CCR7 and PD-1. The engineered Exos secreted by these cells were then collected and loaded with the STING agonist Gauron to construct EmDEX@GA; (B) Through surface CCR7, EmDEX@GA accumulates in tumor-draining lymph nodes (TDLNs) and, via local PD-1/PD-L1 blockade and STING pathway activation, modulates the lymph node immune microenvironment, thereby enhancing antitumor immune responses and suppressing tumor metastasis. Adapted from Wang et al.^[127], used under the CC BY 4.0 license. CCR7: C-C chemokine receptor type 7; PD-1: programmed cell death protein 1; Exos: exosomes; STING: stimulator of interferon genes; PD-L1: programmed death-ligand 1; cGAMP: cyclic GMP-AMP; GMP: guanosine monophosphate; AMP: adenosine monophosphate; CCL: C-C motif chemokine ligand; LN: lymph node; TBK1: TANK-binding kinase 1; IRF3: interferon regulatory factor 3; IFNs: interferons; LNM: lymph node metastasis; DM: distant metastasis.