A non-bactericidal cathelicidin provides prophylactic efficacy against bacterial infection by driving phagocyte influx

• DOI: 10.7554/elife.72849
• Publication Date: 2022-02-23T09:00:42Z
• Authors: Yang Yang; Jing Wu; Qiao Li; Jing Wang; Lixian Mu; Li Hui; Min Li; Wei Xu; Hailong Yang; Lin Wei
• Keywords: Cathelicidin; Phagocyte

The roles of bactericidal cathelicidins against bacterial infection have been extensively studied. However, the antibacterial property and mechanism action non-bactericidal are rarely known. Herein, a novel naturally occurring cathelicidin ( Popu CATH) from tree frog Polypedates puerensis ) did not show any direct anti-bacterial activity in vitro. Intriguingly, intraperitoneal injection CATH before inoculation significantly reduced load frogs mice, inflammatory response induced by mice. pretreatment also increased survival rates septic mice lethal dose or cecal ligation puncture (CLP). Intraperitoneal drove leukocyte influx both In rapidly neutrophil, monocyte/macrophage mouse abdominal cavity peripheral blood with negligible impact on T B lymphocytes, neutrophils, monocytes/macrophages, but were required for preventive efficacy CATH. directly act as chemoattractant phagocytes, obviously phagocyte migration when it was cultured macrophages. elicited chemokine/cytokine production macrophages through activating p38/ERK mitogen-activated protein kinases (MAPKs) NF-κB p65. markedly enhanced neutrophil phagocytosis via promoting release extracellular traps (NETs). Additionally, showed low side effects vitro vivo. Collectively, acts host-based immune defense regulator that provides prophylactic without antimicrobial effects. Our findings reveal which possesses unique action, highlight potential to prevent infection.