Moreover, ESG markedly downregulated the two immune checkpoints, programmed cell death protein-1 (PD-1, in the spleen) and cytotoxic T lymphocyte antigen-4 (CTLA-4, in the tumor), suggesting that ESG could effectively restore the T cell paradigm by recovering the exhaustion status through the suppression of the co-inhibitory checkpoints [106]. Here, PDCD1 is linked to neoplasm.