Neutrophils activated by membrane attack complexes increase the permeability of melanoma blood vessels.

ABSTRACT: The microenvironment of malignant melanomas defines the properties of tumor blood vessels and regulates infiltration and vascular dissemination of immune and cancer cells, respectively. Previous research in other cancer entities suggested the complement system as an essential part of the tumor microenvironment. Here, we confirm activation of the complement system in samples of melanoma patients and murine melanomas. We identified the tumor endothelium as the starting point of the complement cascade. Generation of complement-derived C5a promoted the recruitment of neutrophils. Upon contact with the vascular endothelium, neutrophils were further activated by complement membrane attack complexes (MACs). MAC-activated neutrophils release neutrophil extracellular traps (NETs). Close to the bloo

SUBMITTER: Liu X 

PROVIDER: S-EPMC9388087 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature