CD8⁺T cells with distinct cytokine‐producing features and low cytotoxic activity in eosinophilic and non‐eosinophilic chronic rhinosinusitis with nasal polyps

Abstract

CD8(+) T cells have low cytotoxic activity; nevertheless, they are a significant and previously underappreciated source of inflammatory cytokine production in polyps. Different Tc cell subset domination may contribute to distinctly biased granulocyte inflammation in eosinophilic and non-eosinophilic polyps.

Sinonasal T-Cell Expression of Cytotoxic Mediators Granzyme B and Perforin is Reduced in Patients with Chronic Rhinosinusitis

“…In agreement with previous studies, we did not observe any difference in these mediators systemically. 8,9,23 Our results, however, did differ from studies that evaluated peripheral levels in patients with asthma and chronic obstructive pulmonary disease. [29][30][31][32][33] This further supported the notion that there may be changes in the T cell profile specific to the localized region of the sinonasal mucosa in CRS that results in a loss of cytotoxicity.…”

“…5,[8][9][10]23 Analysis of our data supported these previous findings in that we observed a significant increase in sinonasal CD8…”

“…With regard to comparisons between controls and patients with CRSwNP, similar to Ma et al, 8 we did not find any difference in peripheral blood GrB levels between the groups. However, unlike that study, we did find reductions in sinonasal CD8…”

“…For example, a number of studies found that CD8 ϩ T cells accumulate in the sinonasal tissues of patients with CRS. 5,[8][9][10] Other studies that investigated NK cells found that, in patients with CRS and other allergic airway diseases, NK cells have an impaired ability to produce cytokines and to degranulate, which indicates a dysregulation in effector functions. [11][12][13] In addition, a previous study that analyzed a CRS murine model found that the depletion of NK cells further aggravated eosinophilic inflammation.…”

Functional role of kynurenine and aryl hydrocarbon receptor axis in chronic rhinosinusitis with nasal polyps

“…1,5–7 Various inflammatory cells are implicated in the development of eosinophilic inflammation in CRSwNP, such as dendritic cells, 8,9 basophils, 10 innate type 2 lymphoid cells, 11,12 and lymphocytes. 13,14 Recently, we and others have reported an accumulation of mast cells, particularly activated mast cells in CRSwNP, which correlates with eosinophilia in polyps. 15,16 Furthermore, locally secreted IgE can bind to mast cells in polyps and lead to mast cell activation on allergen exposure.…”