Different types of T-effector cells orchestrate mucosal inflammation in chronic sinus disease.

Background: Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by the accumulation of inflammatory cells; however, an eosinophil predominance is seen in white (Belgian), but not Asian (south Chinese), patients with polyps.
Objective: We sought to investigate the association of inflammatory cell predominance with regulatory T-cell and T-effector cell patterns.
Methods: Nasal mucosal tissue was obtained from 26 consecutive Belgian patients with CRSwNP and 21 Belgian control subjects and 29 south Chinese patients with CRSwNP and 29 south Chinese control subjects, who all underwent phenotyping, including nasal endoscopy and computed tomographic scanning. Tissues were investigated for granulocytes and their products and T-effector/regulatory T cells and related cytokines.
Results: Both CRSwNP groups were comparable in terms of symptoms, computed tomographic scan results, and nasal endoscopy results, but asthma comorbidity was significantly higher in white patients. Tissue from white patients with CRSwNP was characterized by eosinophilic inflammation (eosinophil cationic protein/myeloperoxidase ratio > 2), whereas samples from Asian patients were biased toward neutrophilic inflammation (eosinophil cationic protein/myeloperoxidase ratio = 0.25). Both CRSwNP groups demonstrated significant upregulation of the T-cell activation marker soluble IL-2 receptor alpha and significant downregulation of Foxp3 expression and TGF-beta1 protein content versus their respective control groups. However, whereas white patients displayed a significant increase in T(H)2 cytokine and related marker levels versus control subjects and versus Asian patients, the latter showed a T(H)1/T(H)17 cell pattern versus control tissue.
Conclusion: Nasal polyps (CRSwNP) from white and Asian patients are both characterized by T-cell activation and impaired regulatory T-cell function; however, T-effector cells in the samples from white patients were T(H)2-biased, whereas samples from their Asian counterparts demonstrated a T(H)1/T(H)17 polarization.