Clinical and immunological characteristics of Aspergillus fumigatus-sensitized asthma and allergic bronchopulmonary aspergillosis

Abstract

BackgroundAspergillus fumigatus (A.f) is a common airborne allergen that contributes to allergic asthma. In some patients, A.f can colonize in the airway and lead to allergic bronchopulmonary aspergillosis (ABPA). However, our understanding of the pathogenesis of A.f-sensitized asthma and ABPA remains inadequate.ObjectiveWe aimed to investigate the clinical and immunological characteristics of A.f-sensitized asthma and ABPA.MethodsA total of 64 ABPA and 57 A.f-sensitized asthma patients were enrolled in the study, and 33 non-A.f-sensitized asthma patients served as the control group. The clinical and immunological parameters included lung function, fractional exhaled nitric oxide (FeNO), induced sputum and blood cell analysis, specific IgE/IgG/IgA of A.f and its components, cytokines (IL-33, IL-25, and TSLP) and CD4+T cell subsets.ResultsThe eosinophils in blood, induced sputum, and FeNO were significantly higher in ABPA patients compared to that in A.f-sensitized patients. The combination of FeNO and eosinophils (EO) parameters presented good diagnostic efficiency in differentiating A.f (+) asthma from ABPA, with a sensitivity of 80% and a specificity of 100%. Specific IgE, IgG, and IgA against A.f also increased in ABPA patients. However, serum IL-25, IL-33, and TSLP showed no significant differences between the two groups. Cell analysis showed an increase in IFN-γ+Th1 cells in the ABPA patients. FlowSOM analysis further confirmed that the frequency of CD3+CD4+PD-1+CD127+IFN-γ+T cells was higher in ABPA patients.ConclusionOur findings suggest the distinct humoral and cell immunological responses in A.f-sensitized asthma and ABPA patients. ABPA patients have more severe eosinophilic inflammation and enhanced Th1 responses compared with A.f-sensitized asthma patients.

Impact of Aspergillus fumigatus allergen sensitivity on allergic rhinitis and asthma: a single center retrospective study

“…The current study included both patients diagnosed with allergic asthma and allergic rhinitis, providing an opportunity to observe the effects of A.f sensitivity on both groups. We found similar results to previous studies regarding the impact of A.f sensitivity on allergic asthma [3,9,11,12,16]. However, our study yielded different results regarding the effects on allergic rhinitis.…”

“…Several studies have clearly established a link between A.f sensitization and exacerbations of allergic asthma, which subsequently result in increased morbidity and mortality rates [1,[9][10][11][12]. Additionally, a recent study showed that having A.f sensitivity causes a poor asthma control [3]. Consistent with previous studies, our patient population demonstrated that A.f-sensitized individuals had poorer asthma control, higher asthma severity, and were using higher treatment steps.…”

“…It is a chronic inflammation triggered by repeated exposure to A.f which is colonized in the airway for a long time. Clinical manifestations of ABPA include chronic asthma or bronchiectasis and recurrent pulmonary shadows or mucus blockage in lung images [3][4][5][6].…”

“…A study revealed that the estimated prevalence of ABPA in adults with asthma was 2.5% and could rise up to 45% in patients with A.f-sensitized asthma [3,7,8].…”

Th2-skewed peripheral T-helper cells drive B-cells in allergic bronchopulmonary aspergillosis

“…In a recent study by C hen et al . [ 24 ] in which the exacerbation status of ABPA was not specified and the markers of cell subsets were different, ABPA patients had increased IFN-γ + Th1 cells and similar percentages of IL-4 + Th2 cells and Treg cells when compared with asthma patients. However, in our study, ABPA patients had decreased Th1/Th17 cells, increased IL-5 + Th2 cells and similar Treg cells when compared with healthy controls.…”