Tissue-resident memory T cells exhibit phenotypically and functionally heterogeneous in human physiological and...

Pathogens commonly enter mucosal barrier tissues and tissue-resident memory T cells (T_RM) are essential for preventing mucosal lesions. However, the immunological properties of T_RM cells in nasal mucosa are poorly known. In comparison with control tissues, decreasing CD103⁺ T_RM cells were observed in Chronic rhinosinusitis with nasal polyps (CRSwNPs) and sinonasal inverted papilloma (SNIP), which presented high capability to produce effector cytokines. In CRSwNPs, we found that CD103⁺ T_RM cells with higher cytokine and Granzyme B coexpressed high PD-1, CD103^- T_RM cells expressed higher IL-10. Homogenates isolated from CRSwNPs induced CD103 expression on peripheral T cells which could be inhibited by blocking TGF-β. The frequencies of CD103⁺ T_RM cells in CRSwNPs were extremely negatively correlated with neutrophil infiltration. CD103⁺ T_RM cells from Staphylococcus aureus positive CRSwNPs had a stronger response to SEB. Taken together, two phenotypically and functionally distinct subsets of T_RM cells exist in nasal tissues and play critical roles in the progress of CRSwNPs and SNIPs.