Objective To explore the potential roles and mechanism of Wnt5a and its receptors in the pathogenesis of bronchiectasis. Methods From October 2017 to April 2018, outpatients with bronchiectasis who needed bronchoscopy were recruited in the Department of Respiratory and Critical Care Medicine of West China Hospital of Sichuan University. The control group was patients with pulmonary nodules less than 10 mm in diameter by health inspection. Patients who used antibiotics and/or glucocorticoids within the past 4 weeks or had other airway diseases were excluded. Serum and bronchial mucosa were collected for detection of Wnt5a by enzyme-linked immunosorbent assay and real-time polymerase chain reaction (PCR), respectively. The receptor of Wnt5a, Ror2, and the downstream pro-inflammatory cytokines, interleukin (IL)-1β and IL-6, were measured in the bronchial mucosa by real-time PCR. Results From October 2017 to April 2018, 32 outpatients with bronchiectasis were found but only 17 patients finished this study, and simultaneously 18 patients with pulmonary nodules were chosen as control. The level of serum Wnt5a in patients with bronchiectasis were significantly higher than that in the control group (P<0.05). Correlation analyses showed that serum Wnt5a level was positively correlated with the level of serum C reactive protein (r=0.806, P<0.05), but had no relation with the level of white blood cell count, blood neutrophil percentage, pulmonary function or bronchiectasis severe index. The mRNA levels of Wnt5a and its receptor Ror2 in bronchial mucosa of patients with bronchiectasis were significantly higher than those in the control group (P<0.001). The mRNA levels of IL-1β and IL-6 in bronchial mucosa of patients with bronchiectasis were higher than those in the control group (P<0.05). Conclusion Wnt5a may play crucial roles in the development of bronchiectasis through Wnt5a/Ror2 signaling pathways to regulate the release of pro-inflammatory cytokines including IL-1β and IL-6.
ObjectiveTo analyze the microbiological characteristics of airway bacteria in adult patients with bronchiectasis and to analyze their correlation with the clinical features. MethodsPatients diagnosed with bronchiectasis in the Department of Respiratory and Critical Care Medicine of West China Hospital of Sichuan University from October 2017 to April 2018 were classified into the bronchiectasis group, while the control group was those who were found to have pulmonary nodules (diameter less than 10 mm) requiring bronchoscopy by physical examination. All subjects in both groups had not used antibiotics or hormones within 4 weeks and had no other respiratory diseases. Bronchoalveolar lavage fluid (BALF) from the lesion site of the branchial expansion group was collected, and BALF from the basal segment of the contralateral inferior bronchial lobe of the pulmonary nodule was collected in the control group. Bacterial culture and 16S rRNA gene sequencing were performed in both groups. ResultsSeventeen cases and six controls were enrolled in this study and the BALF specimens were collected. Eight cases were in stable period and nine cases were in acute period. The case group was divided into the bacteria-positive group and negative group based on bacterial culture of BALF. Shannon index in the bacteria-positive group was significantly lower than the bacteria-negative group and the control group. And Shannon index showed a negative correlation with positive bacterial culture in BALF. When Shannon index ≤4.5 was used to predict positive bacterial culture, the sensitivity and specificity were 83.3% and 90.9% respectively. The average relative abundance of bacteria was higher and the average sample distribution uniformity was lower in patients with acute period, compared with those in patients with stable period. Shannon index was negatively correlated with the acute exacerbation in patients. When Shannon index <5.0 was used to predict acute exacerbation, the sensitivity and specificity were 77.8% and 100.0%, respectively. ConclusionsShannon index in 16S rRNA gene sequencing results has certain predictive value for acute exacerbation stage. 16S rRNA gene sequencing combined with bacterial culture results can help guide clinicians to provide more precise treatment plans.