Mouse neutrophil maturity analysis in homeostasis, acute-inflammation and cancer

Purpose: Identification of neutrophils at different stages of maturation and their phenotypic and functional differences remain unknown. The goal of this study was to confirm maturation status of Ly6GIntermediate, Ly6GHigh and Ly6G+ neutrophils, the consistency of this means of identication in disease, and identify functional differences. Methods: Ly6G+, Ly6GIntermediate and Ly6GHigh neutrophil populations were isolated by FACS into individual cell populations from PBS controls, acute-LPS inflammation and pancreatic adenocarcinoma (PDAC) bearing mouse tissues (metastatic KPC, non-metastatic KPflC and WT controls). RNA-Sequencing was performed on bulk isolated populations Results: We identified Ly6GIntermediate as bona-fide immature neutrophils and analysis of Ly6G expression level as a consistently accurate marker of identifying neutrophil maturity. Gene expression was influenced by maturation stage, tissue of isolation, developmental niche and pathology. Function associated expression differences were maintained between Ly6GIntermediate and Ly6GHigh neutrophils throughout tissues and pathology. Overall design: Ly6G+, Ly6GIntermediate and Ly6GHigh neutrophil populations from PBS, LPS, and PDAC mouse models (metastatic KPC, non-metastatic KPflC and WT controls) were isolated from the peripheral blood, bone marrow and spleen