Funding sources for the study: Stanford University Department of Otolaryngology; University of Colorado Department of Otolaryngology; American Academy of Otolaryngology–Head and Neck Surgery.
Systemic prednisone administration selectively alters granulocyte subsets in nasal polyps from aspirin-exacerbated respiratory disease and chronic rhinosinusitis patients
Article first published online: 19 SEP 2013
© 2013 ARS-AAOA, LLC
International Forum of Allergy & Rhinology
Volume 3, Issue 11, pages 866–876, November 2013
How to Cite
How to Cite this Article: Systemic prednisone administration selectively alters granulocyte subsets in nasal polyps from aspirin-exacerbated respiratory disease and chronic rhinosinusitis patients. Int Forum Allergy Rhinol. 2013;3:866–876., , , et al.
Potential conflict of interest: None provided.
- Issue published online: 15 NOV 2013
- Article first published online: 19 SEP 2013
- Manuscript Accepted: 1 AUG 2013
- Manuscript Revised: 27 JUL 2013
- Manuscript Received: 10 MAR 2013
- Stanford University Department of Otolaryngology
- University of Colorado Department of Otolaryngology
- American Academy of Otolaryngology–Head and Neck Surgery
- flow cytometry;
- chronic rhinosinusitis;
- nasal polyp;
- aspirin-induced asthma;
- regulatory T cell;
Nasal polyps (NPs) are hallmark inflammatory lesions of sinusitis. Despite the spectrum of NP conditions, cellular differences between NPs from patients with chronic rhinosinusitis with NPs (CRSwNP) and aspirin-exacerbated respiratory disease (AERD) are poorly understood. NPs are associated with abundant eosinophils; the contributions of neutrophil and basophil granulocytes are less defined. We therefore sought to assess granulocyte subpopulations, and differential effects following prednisone pretreatment, within NPs of CRSwNP and AERD patients.
NPs, adjacent ethmoid sinus tissue, and peripheral blood mononuclear cells (PBMCs) were obtained from patients undergoing endoscopic sinus surgery. Samples from 5 cohorts: CRSwNP ± prednisone (n = 6 each), AERD ± prednisone (n = 6 each), and controls (n = 9), were analyzed by high-dimensional flow cytometry to gate granulocyte populations. Specimens were also assessed using immunohistochemistry (IHC) staining.
Systemic prednisone administration was associated with a lower frequency of eosinophils (p < 0.0001, n = 6) in NPs in both CRSwNP and AERD patients, whereas a decrease in neutrophils (p = 0.0070, n = 6) in NPs was only observed in CRSwNP patients after prednisone treatment. In contrast, steroids do not alter basophil proportions (p = 0.48, n = 6) within NPs from either group. No significant shift in granulocyte subsets after steroid treatment was identified in the adjacent ethmoid mucosa or PBMCs from the same patients. Immunohistochemistry (IHC) staining supported these findings.
Granulocyte subpopulations are focally affected within NPs by systemic steroid exposure, without notable granulocyte alterations in the surrounding regional tissues. These data provide direct insights into the cellular effects of routine prednisone exposure in CRS patients, and highlight a unique microenvironment present within NP lesions.