Continued   6. Nature’s New Discovery: Another Unidentified Anti-cancer Approach of PD-1 / PD-L1 Antibodies doi: 10.1038/nature22396.   On May 17, Nature published an online article titled “PD-1 expression by tumor-associated macrophages inhibits phagocytosis and tumor immunity”, revealing the immune checkpoint inhibitors represented by the PD-1 / PD-L1 antibody can fight cancer in a completely different way.   Dr. Irving Weissman, a professor of pathology and developmental biology at Stanford…