C5 and cancer: Similarly to IL-17A secretion that links antibacterial immunity to the anti-cancer immune response in mice and human,98 101 release of the complement component 5-a (C5a) in the TME is another potent attractant for neutrophils and macrophages in mice and on purified human neutrophils in vitro.104 105 Although the impact of C5a receptor (C5aR) signaling on TAN plasticity and function remains unclear in cancer, the anti-C5aR antagonist antibody IPH5401 is currently tested in the combination with durvalumab anti-PD-L1 antibody (NCT03665129).