Rat models of postintracerebral hemorrhage pneumonia induced by nasal inoculation with Klebsiella pneumoniae or intratracheal inoculation with LPS

作者：Ruihua Wang, Changlian Gan, Rui Mao, Yang Chen, Ru Yan, Geng Li, Tianqin Xiong, Jianwen Guo · 发表于：Frontiers in Immunology · 年份：2025 · DOI：10.3389/fimmu.2024.1477902 · 被引用次数：12 · 研究领域：Intracerebral and Subarachnoid Hemorrhage Research、Immune cells in cancer、Immune Response and Inflammation

Background A stable and reproducible experimental bacterial pneumonia model postintracerebral hemorrhage (ICH) is necessary to help investigating the pathogenesis and novel treatments of Stroke-associated pneumonia (SAP). Aim To establish a Gram-negative bacterial pneumonia-complicating ICH rat model and an acute lung injury (ALI)-complicating ICH rat model. Methods We established two standardized models of post-ICH pneumonia by nasal inoculation with Klebsiella pneumoniae ( Kp ) or intratracheal inoculation with lipopolysaccharide (LPS). Survival and neurological scores were monitored. Magnetic resonance imaging was performed to evaluate hematoma volume. Abdominal aortic blood was collected for leukocyte counting, serum was isolated to determine concentrations of S100β and proinflammatory cytokines using ELISAs. Histopathological changes of brain, lung and gut were assessed using hematoxylin−eosin staining. Lung was isolated for immunofluorescence staining for myeloperoxidase (MPO). Bronchoalveolar lavage fluid was collected for leukocyte counting, and supernatant was prepared to measure MPO activity. Ileum was isolated for immunofluorescence staining for tight junction proteins ZO-1 and γδ TCRs/IL-17A and for Alcian blue–nuclear fast red staining of acidic mucins. Feces were collected, 16S rRNA sequencing, untargeted metabolomics and Spearman’s correlation analyses were performed to explore changes of gut microbiota, metabolites and their interactions. Results In Kp -induce...