Figure 3.

Schematic depiction of the self-assembly of PyroR and its mechanism of photodynamic treatment (PDT) causing immunogenic cell death (ICD) and macrophage polarisation. Pyro and R848 could interact noncovalently between themselves to form PyroR. PyroR could inhibit initial tumour growth by PDT after passively accumulating at the tumour site and polarise macrophages from M2 to M1 phenotype to secrete cytokines. Further, the PDT aids immunotherapy by triggering immunological cascades, such as ICD activation, CRT and HMGB1 release, DC maturation, and lymph node migration. ICD cascades and M1 macrophage polarisation activate T cells to curb metastatic tumours [23]. Reproduced with permissions from Xiayun Chen et al., Chemical Engineering Journal, Elsevier, 2022.