AUTHOR=Zhan Chen , Xu Rong , Li Bizhou , Liu Jiaxing , Liang Wanqin , Zhang Shengfang , Fang Liman , Zhong Shuxin , de Silva S. Dushinka Shaniya Helen , Sivapalan Dhinesan , Luo Wei , Li Jing , Lai Kefang , Zhong Nanshan , Sehmi Roma , O’Byrne Paul M. , Chen Ruchong 

TITLE=Eosinophil Progenitors in Patients With Non-Asthmatic Eosinophilic Bronchitis, Eosinophilic Asthma, and Normal Controls

JOURNAL=Frontiers in Immunology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2022.737968

DOI=10.3389/fimmu.2022.737968

ISSN=1664-3224

ABSTRACT=Objective: To explore the potential of in situ airway differentiation of eosinophil progenitors (EoPs) and hematopoietic progenitor cells (HPCs) in sputum and peripheral blood from patients with non-asthmatic eosinophilic bronchitis (NAEB), eosinophilic asthma (EA) and healthy controls (HC). 
Methods: Using flow cytometry, we enumerated sputum and blood HPCs and EoPs by in patients with NAEB (n=15), EA (n=15), and HC (n=14) at baseline. Patients with NAEB and EA were then treated for one month with budesonide (200ug, bid), or budesonide and formoterol (200/6ug, bid), respectively. HPCs and EoPs in both compartments were re-evaluated. 
Results: At baseline, NAEB and EA both had significantly greater numbers of sputum but not blood HPCs and EoPs (p<0.05) compared to HC. There were no differences between NAEB and EA. After one-month of inhaled corticosteroid (ICS) treatment, NAEB patients showed a significant improvement in cough symptoms but the attenuation of sputum HPC and EoP levels was not significant.
Conclusions: NAEB patients have increased airway levels of HPCs and EoPs. One-month treatment with ICS did not fully suppress the level of EoPs in NAEB. Controlling in situ airway differentiation of EoPs may control airway eosinophilia and provide long-term resolution of symptoms in NAEB