Type II Alveolar Epithelial Cells Promote Sepsis-Induced Immunosuppression in Alveolar Macrophages via Exosomal lncRNA Rmrp Release.

ABSTRACT: Secondary pneumonia, a common complication of sepsis-induced immunosuppression (SII), is closely linked to alveolar macrophage (AM) dysfunction primarily due to impaired glycolytic activity. However, the underlying molecular mechanisms remain unclear. In this study, it is found that exosomal RNA component of the mitochondrial RNA processing endoribonuclease (Rmrp), derived from type II alveolar epithelial cells (AEC-IIs), drives glycolytic defects and immune tolerance in AMs following cecal ligation and puncture (CLP) sepsis. Targeted depletion of Rmrp in either AEC-IIs or AMs alleviated SII and secondary pneumonia induced by Pseudomonas aeruginosa infection 48 h post CLP. Mechanistically, Rmrp interacts with and inhibits the ubiquitination and degradation of the RNA-binding protein zinc f

SUBMITTER: Liu C 

PROVIDER: S-EPMC12766999 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature