RT Journal Article SR Electronic T1 18F-FDG Uptake Rate Is a Biomarker of Eosinophilic Inflammation and Airway Response in Asthma JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1713 OP 1720 DO 10.2967/jnumed.110.086355 VO 52 IS 11 A1 Harris, R. Scott A1 Venegas, José G. A1 Wongviriyawong, Chanikarn A1 Winkler, Tilo A1 Kone, Mamary A1 Musch, Guido A1 Vidal Melo, Marcos F. A1 de Prost, Nicolas A1 Hamilos, Daniel L. A1 Afshar, Roshi A1 Cho, Josalyn A1 Luster, Andrew D. A1 Medoff, Benjamin D. YR 2011 UL http://jnm.snmjournals.org/content/52/11/1713.abstract AB In asthma, the relationship among airway inflammation, airway hyperresponsiveness, and lung function is poorly understood. Methods to noninvasively assess these relationships in human subjects are needed. We sought to determine whether 18F-FDG uptake rate (Ki, min−1) could serve as a biomarker of eosinophilic inflammation and local lung function. Methods: We used PET/CT to assess regional pulmonary perfusion (Q˙), specific ventilation per unit volume (sV˙A), fractional gas content (Fgas), airway wall thickness, and regional Ki 10 h after segmental allergen challenge to the right middle lobe in 6 asthmatic subjects with demonstrated atopy. Q˙, sV˙A, and Fgas in the allergen-challenged lobe were compared with the right upper lobe, where diluent was applied as a control. The airway wall thickness aspect ratio (ω) of the allergen-challenged airway was compared with those of similarly sized airways from unaffected areas of the lung. Differences in Ki between allergen and diluent segments were compared with those in cell counts obtained 24 h after the allergen challenge by a bronchoalveolar lavage of the respective segments. Results: We found systematic reductions in regional Q˙, sV˙A, and Fgas and increased ω in all subjects. The ratio of eosinophil count (allergen to diluent) was linearly related (R2 = 0.9917, P < 0.001) to the ratio of Ki. Conclusion: Regional Ki measured with PET is a noninvasive and highly predictive biomarker of eosinophilic airway inflammation and its functional effects. This method may serve to help in the understanding of allergic inflammation and test the therapeutic effectiveness of novel drugs or treatments.