Resolving cellular networks driving pathogenic CD4+ tissue-resident memory T cells in non-type 2 chronic rhinosinusitis by integrative single-cell and spatial transcriptomic analysis 3537

Abstract Description Chronic rhinosinusitis (CRS) is an immunologically heterogeneous disease of the nasal cavity and paranasal sinuses, categorized into type 2 (T2) or non-T2 inflammatory endotypes. Although refractory non-T2 CRS is highly prevalent in East Asian countries, its pathophysiology remains poorly understood. Here, we assembled a multi-modal cellular and spatial map of CRS by performing single-cell RNA and T-cell receptor sequencing combined with spatial transcriptomic and proteomic analyses. Distinct epithelial cells, such as submucosal glandular cells, in non-T2 CRS exhibited elevated expression of neutrophil activators and T helper (Th) 17-related molecules. Additionally, IL-1β-producing macrophages were highly enriched in non-T2 CRS compared to T2 CRS and control groups. Notably, clonally expanded CD4+ T cells exhibiting pathogenic Th17 phenotypes with tissue-resident features were increased in non-T2 CRS. Bioinformatic inference from single-cell RNA sequencing data, combined with integrated analysis of Luminex multiplex ELISA data and spatial analysis, suggested close interactions between pathogenic cell subsets, which were confirmed by in vitro stimulation assays. Our study identifies distinct pathogenic cellular networks that induce pathogenic Th17 cells, which may serve as a novel therapeutic target in non-T2 CRS. Funding Sources RS-2024-00439160 HI23C1464 Topic Categories Immune Mechanisms of Human Disease (HUM)