Basophil Microparticles in Blood and Nasal Lavage of Chronic Rhinosinusitis and Aspirin Exacerbated Respiratory Disease; New Biomarkers for Basophil Activation
Sunday, March 5, 2017: 2:45 PM
Rooms B312-B313 (Georgia World Congress Center, Building B)
Toru Takahashi, MD, PhD, , , , , , , , , , , , , , , ,
Rationale: Although basophil activation testing has been widely used to measure allergic activity, there are limited biomarkers available to evaluate the degree of basophil activation in clinical samples. Microparticles (MPs) are shed membrane vesicles released from activated cells that have potential as biomarkers for tracking activated inflammatory cells.

Methods: Blood and nasal lavage fluid (NLF) was collected from subjects with chronic rhinosinusitis with nasal polyps (CRSwNP) and aspirin exacerbated respiratory disease (AERD) or normal controls. Heparin-anticoagulated blood was centrifuged to obtain platelet-free plasma. Basophil MPs (BasoMPs:CD203c(+)c-kit(-)MPs) in plasma (plasma-BasoMPs) and in NLF (NLF-BasoMPs) were detected by flow cytometry. Basophil activation was evaluated by analyzing the mean fluorescence intensity of CD203c (CD203cMFI) on BasoMPs.

Results: Blood samples were collected from 9 control, 10 CRSwNP, and 9 AERD subjects. NLF was collected from 22 control, 22 CRSwNP with aspirin tolerant asthma (CRSwNP+ATA) and 29 AERD subjects. When compared with control, plasma-BasoMPs were not increased in CRSwNP (p=0.93) or AERD (p=0.23). CD203c MFI on plasma-BasoMPs was not increased in these two groups (CRSwNP:p=0.74, AERD:p=0.35). NLF-BasoMPs were increased compared to controls but only in AERD (2.5-fold, p<0.03), not in CRSwNP+ATA (p=0.59). CD203cMFI on NLF-BasoMPs was increased in CRSwNP+ATA (p<0.04) and AERD (p<0.0001) compared to controls.

Conclusions Based on plasma-BasoMP levels, the degree of basophil activation in the circulation of CRSwNP and AERD was the same as in control. Based on NLF-BasoMP levels, basophils were more highly activated in nasal tissues of AERD compared to CRSwNP+ATA or controls. Basophil MPs are potential biomarkers for basophil activation in vivo in patients.