Fig. 8

Novel HLA-A2.1-restricted ECM1-derived CTL epitope LA induces a significant DC-CTL and DC-NK antitumour effect. ① Identified novel HLA-A2.1 restricted ECM1-derived CTL epitope LA; ② LA was internalized into DCs mainly through phagocytosis; ③ LA facilitated DC maturation; ④ LA was presented on the surface of DCs via the vacuolar pathway; ⑤ LA passing the phagosome-to-cytosol pathway of DCs was degraded without exerting DC-CTL activation; ⑥ The LA/HLA-A2.1 complex was recognized by the TCR of CD8⁺ T cells. The phosphorylation level of ZAP70 was upregulated, inducing activation of CTL; ⑦ CTL could specifically kill tumour cells (DC-CTL interaction); ⑧ LA-activated TLR4 signal, then activated the p38 MAPK pathway to increase the expression of MICA/B on DCs; ⑨ Upregulated MICA/B expression activated NK cells via MICA/B-NKG2D signal; ⑩ LA enhanced NK antitumour effects (DC-NK crosstalk)