Introduction: Monocyte-derived dendritic cells (moDCs) are antigen-presenting cells capable of directing immune responses toward T-helper 1 (Th1) or T-helper 2 (Th2) phenotypes. The systemic profile of moDCs and their association with Th1/Th2 skewing in chronic rhinosinusitis (CRS) is unclear. The purpose of this study is to characterize circulating moDCs in controls, CRS without nasal polyps (CRSsNP), and CRS with nasal polyps (CRSwNP) and correlate moDCs with Th1/Th2 skewing, mucosal inflammation on computed tomography (CT), and quality of life (QoL).
Study design: Cross-sectional study.
Setting: Tertiary care hospital.
Subjects: Blood was drawn from control (n = 12), CRSsNP (n = 18), and CRSwNP (n = 15) patients during endoscopic sinus surgery.
Methods: Peripheral blood moDCs were analyzed with flow cytometry for expression of HLA-DR, CD209, and CD14. Th1 and Th2 cells were identified by CXCR3 and CCR8 expression, respectively. Lund-Mackay CT scores were assigned by blinded graders. Sino-Nasal Outcome Test 22 (SNOT-22) surveys were completed by patients before surgery.
Results: CRSsNP and CRSwNP displayed elevations in systemic moDCs compared with controls. In CRSwNP, systemic Th2 skewing was observed and circulating CD4+ Th2 cells correlated with percent moDCs. MoDCs strongly correlated with higher Lund-Mackay CT scores in CRSsNP but not in CRSwNP. No relationship between moDCs and SNOT-22 scores was observed for either subset of CRS.
Conclusion: These data support that CRSwNP and CRSsNP display alterations in systemic immune profiles. CRSwNP is characterized by significant elevations in circulating moDCs, which is associated with systemic Th2-biased inflammation. Circulating moDCs are associated with mucosal inflammation on CT imaging in CRSsNP. No association between moDCs and QoL is evident in either CRS subset.
Keywords: Th2 inflammation; chronic rhinosinusitis; dendritic cells; nasal polyposis; t-helper cells.