IL10 and metastatic malignant neoplasm: However, it has been less effective in the treatment of solid tumors due to T cell exhaustion and dysfunction.[31] Recent studies have proved that cytokine IL‐10 can alleviate exhaustion, promote proliferation, and enhance the effector function of T cells, leading to the regression of solid tumors and metastatic cancers.[32, 33] We found that IL‐10 loaded LNPs efficiently improve the efficacy of adoptive transferred OT‐1 CD8+ T cells to solid tumors, inhibiting tumor growth (Scheme 1c).