Analysis of differentiation and functional heterogeneity of neutrophil subsets in the lungs of mice infected with Klebsiella pneumoniae
KONG Yiming
LING Mengyao
ZHANG Jingyuan
YU Zihui
XU Ziying
CUI Jinghua
YUAN Jing
Abstract：Objective To elucidate the differentiation and functional heterogeneity of neutrophil subsets in the lung tissue of mice infected with Klebsiella pneumoniae(Kpn).Methods C57BL/6J mice were selected.An acute pulmonary infection mouse model was established by using the clinical isolated Klebsiella pneumoniae through a pulmonary nebulization delivery device.Twenty-eight mice were randomly divided into the control group and the Kpn infusion group.The pulmonary neutrophils of the mice were detected and analyzed by flow cytometry and single-cell transcriptome sequencing technology.Results Kpn infection induced significant lung damage and led to release of inflammatory cytokines,while recruiting a large number of neutrophils to the lungs.Based on scRNA-seq results,we identified two distinct subsets of lung tissue-recruited neutrophils(G0 and G1)by marker genes.Integrative analysis of differential gene expression and functional gene scoring revealed that G0 exhibited a granule regulation-associated signature,whereas G1 exhibited a phagocytosis-related signature.Both G0 and G1 were determined as mature through the expression of genes including Spi1,Cebpd,and Runx1.Furthermore,CXCR2 as a surface marker associated with neutrophil maturation,was not highly expressed on neutrophils in the lungs during mouse pulmonary infection,which differed from its role in the bone marrow and peripheral blood.Conclusion During pulmonary infection caused by Kpn,neutrophils in lung tissues exhibit significant heterogeneity.The expression of myeloid development-related transcription factors and granule-associated genes present a more accurate maturation status of neutrophils in the lung tissues.This finding is crucial for elucidating the mechanisms underlying neutrophil-mediated immune responses.
Keywords：pulmonary infectionacutemouseKlebsiella pneumoniaeneutrophil heterogeneityflow cytometrysingle-cell transcriptome sequencing technology
Publication Date：2026-01-28
Online Publishing Date：2026-03-16(First online date of this platform, not the publication date of the document)
Pages：7( 14-20 )