CD4 and neoplasm: 4T1 tumor-bearing mice were treated with H-MnO2-PEG/C&D + anti-PD-L1 + light irradiation as described before, and then received i.p. injection of anti-CD4, anti-CD8, or mouse IgG (as the control) at a dose of 200 μg per mouse on day 0 and 5.